TEST BANK for Essentials of Physical Anthropology 10th Edition by Robert Jurmain, Lynn Kilgore, Wend

CHAPTER 1: INTRODUCTION TO PHYSICAL ANTHROPOLOGY Chapter Outline I. Introduction A. Hominins are members of an evolutionary lineage which includes our own species, Homo sapiens, and all extinct bipedal relatives.

1. The 3.7 million year-old footprints at the ancient savanna site of Laetoli, as well as numerous fossil discoveries in Africa, are clear evidence of bipedalism. The footprints in what is now Tanzania in eastern Africa indicate the presence of Australopithecus afarensis.

2. The foot prints at the moon and the Laetoli footprints both represent humankind’s place in nature.

3. Homo sapiens are the result of the same evolutionary forces that produced all other life forms on this planet.

4. Evolution is defined as the change in the genetic structure of a population. a. Evolution can be studied at the microevolutionary or macroevolutionary level. b. It also involves the study of human variation and adaptation.

II. The Human Connection A. Human beings are linked to all other life forms on earth biologically and behaviorally.

1. There is a biological continuum because we are the product of the same evolutionary forces that produced all living things.

2. There is a behavioral continuum between humans and other life forms, especially with the nonhuman primates.

III. Biocultural Evolution A. Biological anthropologists are involved in the study of physiological and biological systems, yet the role of culture must also be considered.

1. Culture is the strategy by which humans adapt to the natural environment.

2. Each culture shapes people’s perceptions of the external environment, or worldview.

3. Culture is learned and not genetically determined, yet the predisposition is profoundly influenced by biological factors. The mutual, interactions between biology and culture is biocultural evolution. a. Biocultural evolution makes humans unique. b. It has resulted in many anatomical, biological, and behavioral changes during the course of human evolution.

IV. What Is Anthropology?

A. In the United States anthropology is divided into four main subfields: a. Cultural (or social) anthropology b. Archaeology c. Linguistic Anthropology d. Physical (or biological) anthropology e. Applied Anthropology refers to practical applications of each of these subfields B. Cultural Anthropology is the study of the patterns of belief and behavior found in modern and historical cultures.

1. Early anthropologists concentrated on producing ethnographies, but later broadened their scope to include anthropologists’ own cultures and the people around them.

2. Ethnographic techniques are now used to study diverse subcultures and their interactions with one another in contemporary metropolitan areas (urban anthropology.)

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C. Linguistic Anthropology is the study of human speech and language and different aspects of culture, such as the role of symbols in society, social identity, and cultural beliefs and ideologies.

1. Linguists examine similarities between contemporary languages to trace historical ties between languages and groups of languages.

2. The spontaneous acquisition and use of language is a uniquely human characteristic. a. Linguistic anthropology also interests physical anthropologists because it provides insights into the processes responsible for the development of language in human evolution.

D. Archaeology is the study of earlier cultures and lifeways by anthropologists who specialize in the scientific recovery, analysis, and interpretation of the material remains of past societies.

1. The primary sources of information are artifacts and other material culture.

2. Archaeologists excavate in order to gain information about human behavior and in broader issues, such as the development of agriculture or the rise of cities.

E. Physical Anthropology is the study of human biology within an evolutionary framework with emphasis on interaction between biology and culture.

1. Physical anthropology and biological anthropology are synonymous. a. The use of the term biological anthropology reflects a shift towards genetics, evolutionary biology, nutrition, adaptation, and growth and development through advances in genetics. b. Origins date back to 19th century “natural historians” who questioned the validity of the Bible (most significantly Charles Darwin).

2. Paleoanthropology is the subfield concerned with the study of anatomical and behavioral human evolution as revealed in the fossil record. a. Paleoanthropologists identify fossil hominin species and their evolutionary relationships and attempt to reconstruct their adaptations and behaviors.

3. Human variation was a major area of interest for early biological anthropologists. a. It was mainly concerned with the most obvious observable physical difference, skin color, body proportions and shape of the head and face. b. Today, human variation offers a perspective on adaptive significance and genetic factors of variation. c. Nutritional anthropologists study relationships between various dietary components, cultural practices, physiology, and aspects of health and disease. d. Molecular anthropologists investigate evolutionary relationships between human populations and nonhuman primates using similarities and differences in DNA. 4. Osteology is the subfield concerned with the study of the skeleton. Knowledge of the structure and function of the skeletal system is crucial for understanding the fossil record, and it forms the foundation for the analysis of archaeologically-derived human skeletal materials. a. Bioarchaeology refers to the study of human skeletal remains from archaeological sites.

5. Paleopathology focuses on the analysis of skeletal samples, noting the incidence of trauma, disease, nutritional deficiency, and any other pathological condition that leaves traces on bones.

6. Forensic anthropology is the application of archaeological and osteological techniques to legal matters. a. Forensic anthropologists help identify and analyze skeletal remains that have legal significance. b. They also aid in the identification of remains after mass disasters; the identification of the September 11 terrorist attack victims is a recent example.

7. Anatomy is an important area of interest; a thorough knowledge of soft tissue anatomy is essential to understanding the biomechanical relationships involved in movement.

8. Primatology is the subfield concerned with the study of nonhuman primate biology and behavior.

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F. Applied Anthropology 1. Applied anthropology is aimed at the practical application of anthropological theories and methods outside of the academic setting, yet it includes both academic and applied methods. a. Forensic anthropologists are a good example of the applied approach.

2. Applied approaches in biological anthropology are numerous.

V. Physical Anthropology and the Scientific Method A. Science is a method for gaining information to explain natural phenomena.

1. A hypothesis is defined as a provisional explanation of phenomena.

2. The hypothesis must be tested through additional quantitative data collection and analysis.

The goal is to falsify the hypothesis through empirical research. a. If the hypothesis cannot be falsified through rigorous testing, then it rises to the level of a theory; a broad statement of scientific relationships substantiated through hypothesis testing. (i) Theories are not absolute truths, since they may be disproved in light of new empirical evidence. (ii) Theories are not facts but tested explanations of facts.

3. Scientific Testing refers to the precise repetition of an experiment or expansion of observed data to provide verification; the procedure by which hypotheses and theories are verified, modified, or discarded. a. Any proposition that is stated as absolute or does not allow the possibility of falsification is not a scientific hypothesis and should never be considered as such.

VI. The Anthropological Perspective A. The anthropological perspective stresses that human beings can only be understood by broadening our perspectives over space and through time.

1. By extending our knowledge to include cultures other than our own, we hope to avoid the ethnocentric bias.

2. In a relativistic view of culture, anthropologists seek information from as many different cultures in as many different ecological circumstances as possible (broadening perspective over space) as we become an increasingly interdependent global community.

Key Terms and Concepts Adaptation, p. 5 Anthropology, p. 4-5 Applied anthropology, p. 11 Artifacts, p. 11 Behavior, p. 6 Bioarchaeology, p. 15 Biocultural evolution, p. 10 Bipedally, p 4-5 Continuum, p. 6 Culture, p. 6 Data, p. 19 DNA (deoxyribonucleic acid), p. 15 Empirical, p. 19 Ethnocentric, p. 21 Ethnographies, p. 11 Evolution, p. 5 Forensic anthropology, p. 16

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Genetic, p. 5 Hominins, p. 3-4 Hypotheses, p. 19 Osteology, p. 15 Paleoanthropology, p. 12 Paleopathology, p. 16 Primates, p. 4-5 Primatology, p. 17 Quadrupedal, p. 21 Quantitatively, p. 19 Relativistic, p. 21 Savanna, p. 3-4 Science, p. 19 Scientific method, p. 19 Scientific testing, p. 20 Species, p. 3-4 Theory, p. 20 Worldview, p. 6 Lecture Suggestions 1. Discuss any previous knowledge students had about anthropology and how this changed after reading the chapter. How does anthropology address the question of what it means to be human?

2. Describe your own research interests and explain how the focus fits into the discipline of anthropology. How does it address broader anthropological questions?

3. Discuss the importance of cultural diversity today. How is culture an adaptive strategy? What examples can students suggest to this question?

4. Ask students to define culture in their own words. Compare students’ definitions to suggest ways that different backgrounds may influence how people regard themselves and their culture.

5. Compare and contrast biological and cultural evolution. What examples do students know of each of these types of change? How are they alike and different? How does each relate to the concept of adaptation?

6. Give various examples of applied anthropology projects and discuss the importance of anthropology in our world today. What current problems do students think could most benefit from an “anthropological perspective”?

7. Expand the discussion of the scientific method. Explore how most people tend to generalize from isolated events and anecdotal information. Point out that this approach differs significantly from that of data collection and hypothesis testing.

8. Explore the differences between objective and subjective data. Suggest that students track the information they receive in one hour, noting whether the information is subjective or objective.

9. Present an interesting current events item to students. Compare, evaluate, and discuss ethnocentric and relativistic viewpoints associated with the story.

10. Present several case studies in physical anthropology and ask students to evaluate what type of approach is being used (e.g., osteological, forensics, primatological, paleopathological, etc.)

Internet Exercises 1. Visit the American Anthropological Association’s web site, http://www.aaanet.org/ to learn more about the discipline of anthropology. What non-academic careers are available for anthropologists?

(For more on Careers in Anthropology, see the link, “Advance Your Career.”)

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2. The official web site for the American Association of Physical Anthropology is http://physanth.org/ What careers are available to physical anthropologists? (At the link http://www.physanth.org/jobpostings you can read current academic postings in Physical Anthropology.)

3. Forensic anthropology is a growing field within physical anthropology. For more on this applied approach, see http://fac.utk.edu/forensic.html. In what areas are forensic anthropologists most commonly employed?

4. For more information on various specialties in anthropology (especially cultural, or social, anthropology), see http://www.discoveranthropology.org.uk/.

Multiple Choice Questions 1. Approximately 3.7 million years ago, two or three hominins left their footprints across the savanna of modern-day Tanzania, clear evidence that: a. apes were present in Tanzania. b. hominins walked bipedally. c. modern-day Tanzania continues to be a savanna environment. d. hominins traveled in small groups. e. Tanzania is 3.7 million years old.

ANS: b REF: Introduction 2. A group of reproductively-isolated organisms that can interbreed and produce fertile offspring is called a(n): a. infrastructure. b. species. c. family. d. hominid. e. populace.

ANS: b REF: Introduction 3. The order Primates includes all of the following except: a. monkeys. b. prosimians. c. humans. d. tarsiers. e. marsupials.

ANS: e REF: Introduction 4. What unique strategy allows humans to adapt to the natural environment? a. Evolution b. Culture c. Biological adaptation d. Walking on two legs e. Genetic change ANS: b

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REF: The Human Connection 5. The term evolution refers to: a. changes in the genetic make-up of a population from one generation to the next. b. the process of biological specialization. c. genetic changes within populations, but not the appearance of new species. d. a response of organisms or populations to the environment. e. patterns of inheritance from parent to offspring.

ANS: a REF: Introduction 6. Human evolution is: a. not subject to the same factors that have produced other species. b. complete and no longer a driving force as it once was. c. subject to the long-term interactions of biology and culture. d. solely the result of biological factors. e. solely the result of cultural factors.

ANS: c REF: Biocultural Evolution 7. Culture, as defined in Chapter 1: a. is important only as it pertains to modern humans. b. is genetically determined and does not alter over time. c. includes only those aspects of human lifestyle that relate to the arts. d. can be defined as the strategy by which humans adapt to the natural environment. e. was not an important factor in human evolution.

ANS: d REF: Biocultural Evolution 8. Which statement is not true of human culture? a. It is learned. b. It includes such things as technology, language, religion, and gender roles. c. It is genetically determined. d. It plays a critical role in human evolution. e. All people are products of human culture.

ANS: c REF: Biocultural Evolution 9. Which of the following is not one of the subfields of anthropology in the United States? a. Cultural b. Physical c. Psychological d. Archaeology e. Linguistics ANS: c REF: What Is Anthropology?

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10. What is meant by the term biocultural evolution? a. Biological changes in a species over time b. Changes in human culture from generation to generation c. The interaction between biology and culture in human evolution d. Biological evolution in all species except humans e. The influence of genetic engineering on culture ANS: c REF: Biocultural Evolution 11. ______ is the practical application of the subfields of anthropology. a. Linguistics b. Archaeology c. Applied anthropology d. Physical anthropology e. Cultural anthropology ANS: c REF: What Is Anthropology?

12. Cultural anthropology: a. was first developed as a discipline in the 17th century. b. includes the recovery and analysis of material culture from earlier civilizations. c. focuses solely on the study of traditional societies. d. has no practical application in modern society. e. is the study of the patterns of belief and behavior found in modern and historical cultures.

ANS: e REF: What Is Anthropology?

13. Ethnographies are: a. detailed descriptive studies of contemporary living peoples. b. studies of only Western European societies. c. studies of nonhuman primates. d. studies done by archaeologists. e. the practical application of anthropological theories.

ANS: a REF: What Is Anthropology?

14. Objects or materials made or modified for use by hominins are called: a. data. b. empiricism. c. ethnographies. d. fossils. e. artifacts.

ANS: e REF: What Is Anthropology?

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15. Archaeologists: a. focus primarily on biological imperatives. b. are interested in human behavior when it pertains to osteology. c. study earlier human groups using artifacts and structures as their evidence. d. never work with physical anthropology. e. only examine complex civilizations that have left architectural ruins.

ANS: c REF: What Is Anthropology?

16. Which subdiscipline of anthropology is concerned with various aspects of human language? a. Primatology b. Linguistic anthropology c. Ethnology d. Applied anthropology e. Anthropometry ANS: b REF: What Is Anthropology?

17. The study of human biology within the framework of human evolution can be said to be the domain of which of the following? a. Cultural anthropology b. Physical or biological anthropology c. Primatology d. Osteology e. Archaeology ANS: b REF: What Is Anthropology?

18. The origins of physical anthropology arose from two areas of interest among 19th-century scientists.

What did these areas concern? a. The origins of modern species and human variation b. The genetic determinants of behavior and osteology c. Nonhuman primates and origins of modern species d. Human variation and osteology e. Human evolution and nonhuman primates ANS: a REF: What Is Anthropology?

19. ____________ is the study of human anatomical and behavioral evolution as evidenced by the fossil record. a. Paleoanthropology b. Osteology c. Primatology d. Anthropometry e. Paleopathology ANS: a

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REF: What Is Anthropology?

20. Fields of inquiry fundamental to studies of adaptation in modern human populations include: a. factors that have produced only visible physical differences. b. factors that have produced only genetic variation. c. traits that typify certain populations that have not evolved as biological adaptations. d. traits that typify certain populations that have evolved as biological adaptation to environment. e. examinations of modern groups but not populations over time.

ANS: d REF: What Is Anthropology?

21. Which of the following includes genetic alterations within populations? a. Macroevolution b. Anatomy c. Osteology d. Paleopathology e. Microevolution ANS: e REF: Introduction 22. Which is not true about paleoanthropology? a. It is the study of human evolution. b. It includes the fossils of ancient reptiles and amphibians. c. Its goal is to identify the various human ancestors. d. It attempts to gain insights into human adaptation and behavior. e. It is a valid way to conduct anthropology.

ANS: b REF: What is Anthropology?

23. Which specialty focuses specifically on the study of skeletal material? a. Paleoanthropology b. Osteology c. Molecular anthropology d. Forensic anthropology e. Paleopathology ANS: b REF: What is Anthropology?

24. Primatology is the study of: a. the beginnings of human evolution. b. human skeletal material. c. skeletal remains at crime scenes. d. diseases in earlier human groups. e. the biology and behavior of nonhuman primates.

ANS: e REF: What Is Anthropology?

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25. Which of the following is not an important reason why primatology has become increasingly important since the late 1950s? a. Behavioral studies have implications for understanding natural forces that have shaped human behavior. b. The behavioral studies of any species provide a wealth of data on adaptation. c. Nonhuman primates are our closest living relatives. d. Many nonhuman primates are threatened or seriously endangered. e. Through primatology we can better address the needs of primitive humans.

ANS: e REF: What Is Anthropology?

26. _______ focuses on the study of skeletal remains from archaeological sites. a. Osteology b. Bioarchaeology c. Paleopathology d. Forensic anthropology e. Primate paleontology ANS: b REF: What Is Anthropology?

27. ________ is the subdiscipline of osteology that is concerned with disease and trauma in earlier populations. a. Forensic anthropology b. Primatology c. Anthropometry d. Paleoanthropology e. Paleopathology ANS: e REF: What Is Anthropology?

28. Forensic anthropologists: a. study disease and trauma in ancient populations. b. apply anthropological techniques to legal matters. c. are primarily concerned with the recovery of material culture remains. d. examine the relationships between medical treatment and culturally determined views of disease. e. study nonhuman primates.

ANS: b REF: What Is Anthropology?

29. Who uses anthropological techniques to assist in crime investigations and to identify skeletal remains in cases of disaster? a. Paleoanthropologists b. Primatologists c. Archaeologists d. Cultural anthropologists

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e. Forensic anthropologists ANS: e REF: What Is Anthropology?

30. What is a hypothesis? a. It is a statement that has been proven to be true. b. It is equivalent to a theory. c. It is a provisional statement regarding certain scientific facts or observations. d. It is proof of a theory and occurs after testing a theory. e. It is a fact from which conclusions can be drawn.

ANS: c REF: Physical Anthropology and the Scientific Method 31. What is the initial step in the scientific method? a. Form a theory b. Form a hypothesis c. Perform an experiment d. Publish a scientific article e. Collect data under precise conditions ANS: b REF: Physical Anthropology and the Scientific Method 32. Which of the following does not apply to theories? a. They are tested explanations of facts. b. They are usually concerned with broader and more universal views. c. They are not absolutes and are open to falsification. d. They are specific statements of scientific relationships that have not been verified. e. They are the result of repeated testing.

ANS: d REF: Physical Anthropology and the Scientific Method 33. The anthropological perspective does not: a. offer a wider appreciation through time and space. b. look at the diversity of the human experience. c. help to avoid ethnocentric pitfalls. d. give a wider appreciation of the human experience. e. narrow our viewpoint of how our species has evolved through time and space.

ANS: e REF: The Anthropological Perspective 34. Which of the following is true of the relativistic view of culture? a. It allows us to understand our own culture from a narrower perspective. b. It allows us to understand other people’s concerns and view our culture from a broader perspective. c. It allows us to judge other species using well-tested human criteria. d. It provides us with data to prove that the human species is better adapted than others.

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e. It allows us to understand which culture is superior to another.

ANS: b REF: The Anthropological Perspective True/False Questions 1. The 3.7 million year-old footprints of two hominins were discovered in a riverbed in Texas.

ANS: False REF: Introduction 2. Physical anthropologists are interested only in the study of biological systems.

ANS: False REF: Introduction 3. All cultures share the same worldview.

ANS: False REF: Biocultural Evolution 4. The anthropological perspective proposes to broaden our viewpoint though time and space.

ANS: True REF: The Anthropological Perspective 5. The focus of anthropology is very narrow and has only two subfields.

ANS: False REF: What Is Anthropology?

6. Forensic anthropology is an applied subfield which benefits from a background in physical anthropology.

ANS: True REF: What Is Anthropology?

7. The human predisposition to assimilate culture and function within it is profoundly influenced by biological factors.

ANS: True REF: Biocultural Evolution 8. Anthropology can be applied to practical issues outside the university setting.

ANS: True REF: What Is Anthropology?

9. Physical or biological anthropologists are only interested in the human fossil record.

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ANS: False REF: What Is Anthropology?

10. Molecular anthropologists have used genetic technologies to investigate the relationships between human populations and between humans and nonhuman primates.

ANS: True REF: What Is Anthropology?

Short Answer Questions 1. What is meant by the term adaptation in a biological sense?

ANS: It is an anatomical, physiological, or behavioral response of organisms or populations to the environment.

REF: Introduction 2. What are the four major subfields of anthropology?

ANS: The subfields are Cultural Anthropology, Linguistics, Archaeology, and Physical (or Biological) Anthropology.

REF: What Is Anthropology?

3. Define the term biocultural evolution.

ANS: It is the mutual, interactive evolution of human biology and culture.

REF: Biocultural Evolution 4. Why are physical anthropologists concerned with studying human variation today?

ANS: Their studies of human variation help us to better understand adaptive significance and to identify factors that have produced physical and genetic variation.

REF: What Is Anthropology?

5. Briefly differentiate between paleoanthropology and paleopathology.

ANS: Paleoanthropology is the study of early hominins and paleopathology is the study of early diseases and injuries in human skeletal remains.

REF: What Is Anthropology?

6. What are the primary steps involved in the scientific method?

ANS: It involves formulating a question, doing background research on what others have done on the subject, determining a hypothesis, developing a research design or methodology, collecting data and doing very precise analysis to test the hypothesis.

REF: Physical Anthropology and the Scientific Method 7. What is a relativistic view of culture and why is it important in anthropology?

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ANS: It is an approach that allows anthropology to view other cultures from a broader perspective, by viewing them as they relate to something else. It is very important because our world is increasingly interdependent.

REF: The Anthropological Perspective Essay Questions 1. Define osteology and then discuss which subfields of physical anthropology require knowledge of osteology.

ANS: Will vary REF: What Is Anthropology?

2. Explain what “the anthropological perspective” means and why it is important.

ANS: Will vary REF: The Anthropological Perspective

3. What is the role of the scientific method in physical anthropology? Discuss the various steps and how they might be applied to a specific case study in physical anthropology.

ANS: Will vary REF: Physical Anthropology and the Scientific Method 4. Explain each of the subfields of anthropology and how they each contribute to our understanding of what it means to be human.

ANS: Will vary REF: What Is Anthropology?

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CHAPTER 2: THE DEVELOPMENT OF EVOLUTIONARY THEORY Chapter Outline I.

Introduction A. Misconceptions about evolution result from the poor quality of education (particularly science education) in the U.S. B. By the end of this course, due to studies in evolution students will learn what we know to be true in science: 1. Earliest human ancestors evolved from a species that lived 6 to 8 million years ago.

2. Humans separated from the last common ancestor with monkeys some 20 million years ago.

C. In the United States, evolution is considered to run counter to religious beliefs and is often denigrated as being “only” a theory.

1. Evolution is, in fact, a scientific theory that has a wealth of support and is the unifying theory of the biological sciences, including physical anthropology.

II. A Brief History of Evolutionary Thought A. Discoveries of evolutionary principles took place in Western Europe through many ideas borrowed from other non-western cultures.

B. Charles Darwin is credited with explaining the basic mechanics of the evolutionary process and formulating the theory of natural selection; Alfred Russel Wallace independently reached the same conclusion.

C. The predominant European worldview throughout the Middle Ages was that all aspects of nature, including all life and their relationships, never changed.

1. Christian teachings that God created all life were taken literally. a. The universe was perceived as being part of the Grand Design, created as recently as 4004 B.C. 2. The belief that the earth was very young, coupled with the notion of fixity of species, was a significant obstacle to the development of evolutionary thought.

D. The Scientific Revolution 1. In Europe, the scientific revolution developed as fundamental ideas of the earth and the biological world were overturned. However, in Arabia and India, scholars developed concepts of planetary motion centuries earlier.

2. Europe made scientific advances due to: a. Discovery of the New World. b. Circumnavigation of the globe. c. Emerging intellectual ideas: i. In 1514, Copernicus argued that the earth was not the center of the universe. ii. In the 1600s, Galileo Galilei restated Copernicus concepts’ and was sentenced to house arrest. iii. The laws of physics, motion, and gravity were developed throughout the 16th and 17th centuries. iv. Invention of scientific instruments, including the microscope.

E. Precursors to the Theory of Evolution 1. The first step to understanding the many forms of organic life was to list them and describe them. a. John Ray (1627-1705), a minister at Cambridge University, was first to recognize that groups of plants and animals could be distinguished from other groups by their ability to produce offspring. i. These groups of reproductively isolated organisms were termed species.

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ii. Ray also coined the term genus, recognizing that similar species could be grouped together. b. Carolus Linnaeus (1707-1778), a Swedish naturalist and believer in the fixity of species, developed the binomial nomenclature system of classification plants in his publication, Systema Naturae (1735). i. Taxonomy added class and order. ii. Humans were classified as genus Homo species sapiens. c. George-Louis Le Clerc de Buffon (1707-1788) stressed the importance of change in the universe and the dynamics between nature and living forms in Natural History (1749). d. Erasmus Darwin (1731-1802), Charles Darwin’s grandfather, was a freethinking physician who wrote about evolutionary ideas in poetic verse. i.

The degree to which he influenced his grandson’s ideas is unclear. e. Jean-Baptiste Lamarck (1744-1829) was the first to propose an explanation of the evolutionary process. i.

He proposed a theory of the inheritance of acquired characteristics, in which an animal’s body parts are altered through use or disuse. (a) These altered characteristics are transmitted to their offspring. (b) Although this is biologically impossible, he is credited with being the first to recognize the importance of the interaction between organisms and their environment in the evolutionary process. ii.

He coined the term biology to refer to the study of living organisms. f. Georges Cuvier (1769-1832) was a French vertebrate paleontologist who was an opponent of Lamarck’s evolutionary ideas. i. Cuvier introduced the concept of extinction to explain the existence of hitherto unknown fossil forms. ii. Cuvier was a proponent of catastrophism, the idea that the earth’s geological features are a result of catastrophic events. (a) These events destroyed old life forms, and the newer forms were the result of creation events. g. Thomas Malthus (1766-1834), an English clergyman and economist, wrote An Essay on the Principles of Population. i.

He noted that population sizes increase exponentially but food supplies remain stable. (a) This concept inspired both Charles Darwin and Alfred Wallace. h. Charles Lyell (1797-1875), author of Principles of Geology (1830-1833), is considered the founder of modern geology. i.

He demonstrated that uniform processes (uniformitarianism) could account for present geological features. (a) His ideas provided the “deep time” necessary for biological evolution to have occurred. i. There were other precursors who are less recognized today. i.

Mary Anning was trained by her father to hunt fossils. (a) Discovered the first Pleiosaurus. (b) Contributed to what we understand of the evolution of marine life.

F. The Discovery of Natural Selection 1. Charles Darwin (1809-1882) proposed the first credible mechanism for evolutionary change, natural selection, in On the Origin of the Species (1859). a. After graduating from Cambridge University, where he studied theology but also cultivated his interests in natural science and geology, he was recommended to join the five-year expedition of the HMS Beagle.

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i.

Darwin began the voyage as a believer in the fixity of species, but his observations of, among other things, fossils of giant ancient versions of living animals and varieties of Galápagos finches eventually convinced him to the contrary. ii.

A concept of evolution was prevalent in European scientific circles at the time. (a) There was a growing Reform Movement in England to undo the inequalities of the class system. (b) Evolutionary ideas were seen as related to these types of reforms and were socially feared by certain groups. b. After his return to England in October 1836, Darwin began to formulate the theory of natural selection based on what he had observed, especially of Galapagos finches. i.

He began experiments in selective breeding with domesticated animals, developing and testing the theory of natural of selection. ii.

He wrote summaries of his ideas by 1844, but felt he needed more evidence before he published.

G. In Darwin’s Shadow 1. Alfred Russel Wallace (1823-1913) developed his own theory of natural selection after collecting bird and insect specimens in Southeast Asia. a. He first published some of his ideas in 1855, and then in 1858, Wallace wrote “On the Tendency of Varieties to Depart Indefinitely from the Original Type.” b. These papers caused Lyell and others to urge Darwin to publish his work. Wallace later sent his papers to Darwin which spurred him to put his ideas in writing On the Origin of Species (1859.)

III. Natural Selection A. Darwin envisioned natural selection as a process in which individuals with favorable variations survive and reproduce at a higher rate than those with unfavorable variations. The basic processes, as he understood them, are as follows: 1. All species are capable of producing offspring at a faster rate than food supplies increase.

2. There is biological variation within all species.

3. In each generation more offspring are produced than survive, and because of limited resources, there is competition among individuals.

4. Individuals who possess favorable traits have an advantage; they have greater fitness because favorable traits increase the likelihood that they will survive to adulthood and reproduce.

5. The environmental context “determines” whether or not a trait is beneficial.

6. Traits are inherited and passed on to the next generation. Because individuals who possess favorable traits contribute more offspring to the next generation, over time those favorable traits become more common in the population. Individuals who produce more offspring at a higher rate have greater reproductive success.

7. Over long periods of geological time, successful variations accumulate in populations, resulting into later generations being distinct; thus new species appear.

8. Geographical isolation may lead to the formation of new species because over time populations in distinct areas face different selective pressures.

B. Natural Selection in Action 1. One of the most frequently cited examples of natural selection is the coloration changes of a species of moth. a. Prior to the 19th century in England, the most common variety of peppered moth was a mottled gray color. During the day, the moths would rest on the lichen-covered tree trunks and their coloration provided camouflage. Due to changes driven by industrialization, coal dust covered the tree trunks, killed the lichen, and the mottled gray moths became more conspicuous and targeted by birds and over time the moths’

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(subjective to selective pressures) numbers dwindled. Darker moths then became more common. i.

Evolutionary shifts in response to the environment are called adaptations. b. Natural selection has been demonstrated on the Galápagos Islands. i.

Measurements of beak thickness that changed through time among the medium ground finch indicate the thicker-beaked individuals had greater reproductive success during droughts. c. Natural selection, through the use of antibiotics by humans, is responsible for the increased number of antibiotic-resistant strains of microorganisms. d. These examples of natural selection in action indicate that certain common principles apply. i.

A trait must be inherited if natural selection is to act on it. ii.

Natural selection cannot occur without variation in inherited characteristics. iii.

Fitness is a relative measure that will change as the environment changes. Fitness is differential reproductive success. iv.

Natural selection can act only on traits that affect reproduction.

C. Natural Selection and Reproductive Success 1. Natural selection acts through not only differential death rates, but also through differential fertility rates. a. This leads to a differential net reproductive success.

IV. Constraints on 19th Century Evolutionary Theory A. Darwin argued that natural selection acts on variation within species, yet could not explain the source of this variation.

D. Darwin also did not know how favorable traits were passed from generation to generation.

1. The laws of heredity were unknown, and most believed that parental traits were blended in the offspring.

2. Gregor Mendel had worked out the modern principles of heredity, but his work was not recognized until the beginning of the 20th century.

3. In 1953, the DNA structure was identified and the field of genetics became supportive evidence for evolutionary theory.

4. In 2003 the human genome was sequenced, followed by the chimpanzee genome in 2005.

V. Opposition to Evolution Today A. Darwin’s formulation of evolution was offensive to some Christians and some Muslims.

B. Today, evolution is considered to be a fact by most biologists.

1. Most belief systems do not emphasize biological continuity between species or offer scientific explanations for natural phenomena 2. Scientific explanations are grounded in data analysis, hypothesis testing and interpretation, while religion is a system of faith-based ideas not amenable to scientific testing and falsification. a. Yet, evolutionary theories are accepted, in part, by the Catholic Church and most mainstream Protestants.

3. Most fundamentalists reject all scientific explanations of evolution.

C. A Brief History of Opposition to Evolution in the United States 1. After WWI conservative Christians in U.S. revived “traditional values” and avoided mention of Darwinism in public schools.

2. “Scopes Monkey Trial,” involved John Scopes who was arrested and tried for teaching evolution

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a. Christian fundamentalists oppose the teaching of evolution in public schools at the prebaccalaureate level, although recent attempts to legislate against the teaching of evolution have been overturned in courts. i.

Creationists have dropped the term “creationism” in attempts to mask their fundamentalist ideologies with less religious-sounding terms such as “intelligent design theory.”

Key Terms and Concepts Binomial nomenclature, p. 29 Biological continuity, p. 43 Catastrophism, p. 31 Christian fundamentalists, p. 44 Fertility, p. 41 Fitness, p. 38-39 Fixity of species, p. 27 Genome, p. 42 Natural selection, p. 26 Reproductive success, p. 38-39 Reproductively isolated, p. 29 Selective pressures, p. 38-39 Taxonomy, p. 29 Uniformitarianism, p. 32

Lecture Suggestions 1. Present the various theories on life-forms (fixity of species, catastrophism, uniformitarianism, and natural selection). Discuss with students which pieces of these theories continue to be used in popular culture despite evidence to the contrary.

2. Very carefully review the differences in science between hypotheses, facts, theories, and laws.

3. Most students have heard of Darwin, but few really understand the full impact of his ideas, not only on scientific thought but also on his personal life. The video Charles Darwin: Evolution’s Voice from A&E’s Biography series is particularly relevant. Be sure to reinforce the fact that Darwin waited over twenty years to publish his ideas after returning from the voyage of the HMS Beagle, mostly because he was aware that his theories ran contrary to widely-accepted Biblical doctrines.

4. The Human Genome Project has allowed many advances in medicine and molecular studies. Use the Project as a case study in class, providing a background on the work and its implications.

Internet Exercises 1. Visit the National Center for Science Education’s website, http://ncse.com/ and read about creationist attempts to teach “creation science” in public schools. Use the “Critiques of Creationism” link and write a paragraph summarizing one of the critiques.

2. One historical figure that vehemently opposed Darwin’s ideas was Louis Agassiz (1807-1873). Go to the University of California, Berkeley’s Museum of Paleontology website for information on Agassiz http://www.ucmp.berkeley.edu/ and write a brief paragraph on his life and ideas.

3. Evolution is both a simple and complex theory, depending on how it is taught. Discuss with students the wide-ranging applications of evolution in medicine today. University of California-Berkeley has an excellent website on “understanding evolution” with teaching suggestions and materials at: http://evolution.berkeley.edu/evolibrary/article/medicine_01.

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4. Visit the PBS Evolution website and select several of the lesson plans, activities, and videos about evolution to enhance understanding and class discussion on evolution (www.pbs.org/evolution).

Multiple Choice Questions 1. In Europe during the Middle Ages, it was most commonly believed that: a. all species had evolved from a common ancestor. b. evolution was the result of natural selection acting upon genetic variation. c. all forms were created by God and did not change over time. d. most species had become extinct over time. e. life was created slowly, over millions of years.

ANS: c REF: A Brief History of Evolutionary Thought 2. The concept of a theory in science is associated with all of the following except: a. it has robust support. b. it has been tested. c. it has not been disproved. d. it is a hunch or intuitive idea. e. it has evidentiary support.

ANS: d REF: A Brief History of Evolutionary Thought 3. What is the belief that species do not change but are the same as when they were first created? a. Fixity of species b. The Great Chain of Being c. Catastrophism d. Uniformitarianism e. Natural selection ANS: a REF: A Brief History of Evolutionary Thought 4. Growing attacks on traditional beliefs occurred simultaneously with growing awareness of biological diversity. _________challenged a notion proposed by Aristotle to account for the movement of the sun and planets. a. Copernicus b. Linnaeus c. Darwin d. Wallace e. Mendel ANS: a REF: A Brief History of Evolutionary Thought 5. Several events combined to alter Western Europeans’ ideas about the earth by the 18th century. These did not include: a. the circumnavigation of the globe. b. the discovery of the New World.

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c. the notion of a sun-centered universe. d. a less than rigid feudal class system. e. the invention of the microscope.

ANS: d REF: A Brief History of Evolutionary Thought 6. Populations which are prevented from mating and producing fertile offspring are: a. reproductively isolated. b. less subject to selective pressures. c. considered part of the same taxonomic species. d. not in biological continuity. e. infertile.

ANS: a REF: A Brief History of Evolutionary Thought 7. _________first recognized that species were groups of organisms that were distinguished from other such groups by their ability to mate with one another and produce fertile offspring. a. John Ray b. Charles Darwin c. Carolus Linnaeus d. Alfred Russel Wallace e. Jean-Baptiste Lamarck ANS: a REF: A Brief History of Evolutionary Thought 8. _________refined the existing system of classifying biological organisms into a binomial system. a. Jean-Baptiste Lamarck b. Georges Cuvier c. Carolus Linnaeus d. George-Louis Leclerc de Buffon e. Erasmus Darwin ANS: c REF: A Brief History of Evolutionary Thought 9. Carolus Linnaeus: a. established a binomial system of classification for plants and animals. b. was a proponent of evolutionary change. c. opposed all notions of fixity of species. d. was a supporter of Charles Darwin. e. developed theories of natural selection.

ANS: a REF: A Brief History of Evolutionary Thought 10. _________ was an 18th century thinker who believed that living forms changed in response to the environment yet still rejected the idea that one species could give rise to another. a. Alfred Russel Wallace

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b. c. d. e.

Georges-Louis Leclerc de Buffon Erasmus Darwin John Ray Georges Cuvier

ANS: b REF: A Brief History of Evolutionary Thought 11. Charles Darwin was not the only one to conceive of natural selection. Who also published an article suggesting current species were descended from other species? a. Jean Baptiste Lamarck b. Erasmus Darwin c. Georges-Louis Leclerc de Buffon d. Alfred Russel Wallace e. John Scopes ANS: d REF: A Brief History of Evolutionary Thought 12. Who was the first to actually attempt to explain the mechanism by which species change? a. Carolus Linnaeus b. Jean-Baptiste Lamarck c. Charles Lyell d. Charles Darwin e. Erasmus Darwin ANS: b REF: A Brief History of Evolutionary Thought 13. During the voyage of the Beagle Darwin noted the variations in Galapagos finches between beak size and: a. diet. b. altitude. c. exercise. d. longevity. e. body size.

ANS: a REF: A Brief History of Evolutionary Thought 14. Who coined the term “biology”? a. Jean-Baptiste Lamarck b. Georges Cuvier c. Thomas Malthus d. Charles Darwin e. Charles Lyell ANS: a REF: A Brief History of Evolutionary Thought

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15. What is the term for the theory stating that characteristics acquired during the lifetime of an individual could be passed on to that individual’s offspring? a. Natural selection b. Catastrophism c. Use-disuse theory d. Uniformitarianism e. Fixity of species ANS: c REF: A Brief History of Evolutionary Thought 16. What is the view that the extinction and the subsequent appearance of more modern forms could be explained by a series of disasters and creations? a. Natural selection b. Catastrophism c. Use-disuse theory d. Uniformitarianism e. Descent with modification ANS: b REF: A Brief History of Evolutionary Thought 17. ________was the opponent of Jean-Baptiste Lamarck and the proposer of the view that the earth’s geological landscape is the result of violent cataclysmic events. a. Charles Lyell b. Alfred Russel Wallace c. Thomas Malthus d. Erasmus Darwin e. Georges Cuvier ANS: e REF: A Brief History of Evolutionary Thought 18. _________wrote the highly praised Principles of Geology in which was emphasized the principle of uniformitarianism. a. Charles Darwin b. Charles Lyell c. Alfred Russel Wallace d. Jean-Baptiste Lamarck e. Thomas Malthus ANS: b REF: A Brief History of Evolutionary Thought 19. Thomas Malthus did not: a. propose that human population today is not related to the availability of resources. b. argue that in nature resource availability remains relatively stable over time. c. influence the development of Darwin’s and Wallace’s theories of natural selection. d. argue that in nature there is a tendency for animal population to increase in number. e. argue for limits to human population growth.

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ANS: a REF: A Brief History of Evolutionary Thought 20. Natural selection merged with the work of __________ in the 20th century to open up our understanding of evolutionary theory. a. Erasmus Darwin b. Alfred Russel Wallace c. Gregor Mendel d. Charles Lyell e. Jean-Baptiste Lamarck ANS: c REF: Constraints on 19th-Century Evolutionary Theory 21. Which concept, proposed by Charles Lyell, had a profound effect on 19th-century scientific thought? a. Recent origins for earth b. The role of catastrophic events in producing geological phenomena c. Natural selection d. The immense age of the earth e. The inheritance of acquired characteristics ANS: d REF: A Brief History of Evolutionary Thought 22. The principle of uniformitarianism: a. stated that the geological processes that operated in the past are still occurring in the present. b. was a problem for the development of evolutionary theories. c. proposed that the earth was only a few thousand years old. d. was the same as the theory of catastrophism. e. was first proposed by Georges Cuvier.

ANS: a REF: A Brief History of Evolutionary Thought 23. Alfred Russel Wallace is best known for: a. the principle of uniformitarianism. b. being the co-discoverer of natural selection. c. finding numerous important fossils during the 19th century. d. finding numerous important fossils during the 18th century. e. identifying changes in the coloration of a species moth.

ANS: b REF: A Brief History of Evolutionary Thought 24. Charles Darwin: a. grew up in modest circumstances. b. began to doubt the fixity of species during a voyage around the world in the 1830s. c. received no formal education. d. spent two years in Africa where he developed the theory of natural selection. e. was a physician who studied natural history as a hobby.

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ANS: b REF: A Brief History of Evolutionary Thought 25. In formulating his theory of natural selection, Darwin did not: a. recognize the importance of biological variation within a population. b. apply his knowledge of domesticated species to undomesticated ones. c. appreciate the fact that population size is limited by availability of food. d. wonder if he had enough supportive data. e. claim that favorable variations would tend to be destroyed, unfavorable ones be preserved.

ANS: e REF: A Brief History of Evolutionary Thought 26. The fact that individuals who possess favorable traits are more likely to survive and reproduce than those who possess less favorable traits is the basis for which theory? a. Uniformitarianism b. Natural selection c. The inheritance of acquired characteristics d. Catastrophism e. The fixity of species ANS: b REF: Natural Selection 27. Which of the following concepts did NOT influence Darwin in developing his theory of evolution? a. Population size increases more rapidly than food supplies. b. There is competition among individuals for resources. c. Species are unchanging types, and individual variation within a species is not important. d. There is biological variation in all members of a species. e. Favorable variations are passed on and accumulate in populations over time.

ANS: c REF: Natural Selection 28. Darwin argues that: a. there is biological variation within all species. b. there are fewer selective pressures on well-adapted species. c. in each generation all offspring survive in the most adapted species. d. fitness is a measure of how healthy and physically adapted an individual is. e. individuals who have more resources are reproductively successful.

ANS: a REF: Natural Selection 29. In the example of the peppered moth and changing camouflage colors, which one is best considered the selective agent? a. Trees b. Peppered moths c. Grey moths d. Birds e. Coal dust

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ANS: d REF: Natural Selection 30. Regarding the example of the peppered moth, which of the following is not true? a. The two color patterns resulted from genetic variation in the species. b. It has recently come under criticism. c. Natural selection acted upon pre-existing variation in the population. d. The dark is more visible on the trees darkened by pollution. e. The most common variety of the peppered moth in England, prior to the 19th century, was a mottled gray color.

ANS: d REF: Natural Selection 31. Which is the best example of natural selection? a. The peppered moth b. The medium ground finch of the Galápagos c. The recent increase in resistant strains of disease-causing microorganisms d. The recent decrease in resistant strains of disease-causing microorganisms e. Mendel’s project with peas and beans ANS: c REF: Natural Selection 32. Fitness, in an evolutionary sense, refers to an individual’s: a. strength. b. reproductive success. c. aggressiveness. d. size. e. age at death.

ANS: b REF: Natural Selection 33. In explaining the origins of variation within species, Darwin: a. used Mendel’s theory of heredity. b. agreed with Lamarck that it was caused by an animal’s inner needs. c. argued it was caused by differential use of an animal’s body parts. d. had no idea of the true causes. e. used research he carried out while at Cambridge.

ANS: d REF: Natural Selection 34. Which is the most common reason that about half of Americans do not believe in evolution? a. Most Americans are religiously fundamentalist and do not believe in science. b. The mechanisms of evolution are complex and do not lend themselves to simple explanations. c. Most people possess extensive familiarity with the principles of genetics and know that evolution could not occur. d. Most have not read or studied science in school.

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e. Most people do not want clear-cut answers.

ANS: b REF: Opposition to Evolution Today

True/False Questions 1. Evolution is a theory that has considerable support from genetic evidence.

ANS: True REF: Introduction 2. The most critical mechanism of evolutionary change is natural selection.

ANS: True REF: A Brief History of Evolutionary Thought 3. We credit Erasmus Darwin with significantly influencing Charles Darwin’s evolutionary thinking.

ANS: False REF: A Brief History of Evolutionary Thought 4. The theory of the inheritance of acquired characteristics has recently displaced natural selection as mainstream science’s most accepted theory of evolutionary change.

ANS: False REF: A Brief History of Evolutionary Thought 5. Charles Lyell, author of Principles of Geology, is considered the founder of modern geology.

ANS: True REF: A Brief History of Evolutionary Thought 6. Charles Darwin recognized the importance of beak variation in finches while visiting the Galápagos Islands.

ANS: False REF: A Brief History of Evolutionary Thought 7. Charles Darwin acknowledged the importance of selective pressure when formulating his theory of natural selection.

ANS: True REF: A Brief History of Evolutionary Thought 8. Natural selection operates on populations, but it is individuals who evolve.

ANS: True REF: Natural Selection 9. There are no well-documented examples of natural selection operating on natural populations.

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ANS: False REF: Natural Selection 10. Creationism is considered a science because it has testable hypotheses.

ANS: False REF: Opposition to Evolution Today

Short Answer Questions 1. Many people argue that evolution is “just a theory.” Define theory and describe how evolution does or does not fit this definition.

ANS: In science a theory is something that has been tested and has robust support. Evolution provides various cases of support from the peppered moth to current disease challenges.

REF: Introduction 2. Outline Lamarck’s theory of inheritance of acquired characteristics. According to this theory, what was the environment’s role in biological change?

ANS: Under Lamarck’s theory an animal’s activity patterns would cause change in their physical make-up; those parts used would expand and those not used would decrease.

REF: A Brief History of Evolutionary Thought 3. Compare and contrast catastrophism and uniformitarianism.

ANS: Both are theories to explain change, but both explain it in different ways. Catastrophism argues that the earth’s geological landscape is the result of violent cataclysmic events. As these events occurred, some forms of life became extinct and later repopulated by migrating species from other areas. Uniformitarianism argues that the earth’s features are the result of long-term processes, leaving the earth as a product of deep geological time.

REF: A Brief History of Evolutionary Thought 4. What is natural selection?

ANS: Natural selection is the key evolutionary mechanism – that all species produce offspring faster than the food supply, that there is biological variation within all species, that in each generation more offspring are born than survive, that more favorable traits lead to more fit individuals, that the environment determines which traits are favorable, that traits are inherited and passed on to yield greater reproductive success overall, that accumulations of changes over time may lead to a new species, and that geographical isolation contributes to the formation of a new species through selective pressure.

REF: Natural Selection 5. Define what Darwin meant by the concept of fitness.

ANS: It is a measure of the relative reproductive success of individuals.

REF: Natural Selection 6. What is meant by biological continuity?

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ANS: It is when expressions of a phenomenon continuously grade into one another so that there are no discrete categories of difference.

REF: Opposition to Evolution Today

Essay Questions 1. Present and discuss the fundamentals of evolutionary change produced by natural selection.

ANS: Will vary REF: Natural Selection 2. What is the “theory of evolution” based on what you have learned in this chapter? Consider the brief history presented about the concept and the emergence of natural selection. How do these all address the issue of “evolution”?

ANS: Will vary REF: A Brief History of Evolutionary Thought 3. Many people in the United States believe in the Biblical creation. What various kinds of factors may account for the fact that many people do not accept evolution as an explanation for the origins and diversity of life?

ANS: Will vary REF: Opposition to Evolution Today

4. Explain why and how Charles Lyell’s principle of uniformitarianism and Thomas Malthus’ argument on population growth and resource availability were important to Charles Darwin and Alfred Russel Wallace as they developed their theories of biological evolution.

ANS: Will vary REF: A Brief History of Evolutionary Thought

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CHAPTER 3: THE BIOLOGICAL BASIS OF LIFE Chapter Outline I.

Introduction A. Genetic discoveries and genetically-based technologies are advancing daily and affect our lives.

B. Genetics is the study of how genes work and how traits are transmitted from one generation to the next.

1. Genetics unifies the various subdisciplines of physical anthropology.

II. Cells A. Cells are the basic units of life in all organisms.

1. Some organisms are single-celled and others, called multicellular organisms, are composed of billions of cells.

2. An adult human body may be composed of as many as a trillion cells, all functioning in complex ways that ultimately promote the survival of the individual.

3. Bacteria and blue-green algae appeared about 3.5 billion years ago.

4. Eukaryotic cells (found in multi-cellular organisms) appeared about 1.7 billion years ago. a. The cells are a three-dimensional structure composed of carbohydrates, lipids, nucleic acids, and proteins. (i) Substructures called organelles, include the nucleus surrounded by the nuclear membrane. (a) Inside are two kinds of molecules, which contain genetic information in the form of DNA (deoxyribonucleic acid) and RNA (ribonucleic acid.) (ii) The cytoplasm surrounds the nucleus and contains various organelles involved in cell and organ function through protein synthesis. Among these organelles are the mitochondria and ribosomes. (a) The mitochondria function in energy production and have their own DNA mitochondrial DNA (mtDNA).

5. There are two cell types. a. Somatic cells are the cellular components of body tissues. b. Gametes are sex cells: either sperm or ova. (i) Two gametes fuse to form a zygote.

III. From DNA to Protein A. DNA is the basis of life and directs all cellular activities.

1. The chemical and physical properties of DNA were discovered in 1953 by Crick and Watson.

2. The DNA molecule is composed of two complementary chains of smaller units called nucleotides. a. A single nucleotide is composed of a deoxyribose sugar, a phosphate group, and one of four nitrogenous bases. (i) The bases are adenine, guanine, thymine, and cytosine (A, G, T, C). (ii) The double helix forms because adenine bonds to thymine and guanine bonds to cytosine. (iii) This complementary base bonding is the key to DNA’s ability to replicate itself.

B. DNA replication is key to growth and healing of injured tissue in organisms and occurs before the cell divides.

1. Initially, enzymes break the bonds between the two DNA strands.

2. The exposed bases attract unattached complementary DNA nucleotides.

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3. The two parental nucleotide chains serve as models for the growing replicated strands. a. Thus, each new DNA molecule consists of one original nucleotide chain joined to one new nucleotide chain.

C. One of the most important activities of DNA is to direct protein synthesis within cells.

1. Proteins are complex, three-dimensional molecules with the ability to bind to other molecules. a. The protein hemoglobin, found in red blood cells, is able to transport oxygen through the body because of its ability to bind to oxygen.

2. Some proteins are structural while others (such as enzymes and hormones) are functional. a. Enzymes regulate chemical reactions. b. Specialized cells produce hormones, which target tissues and have specific effects.

3. Proteins are composed of amino acids. a. There are 20 amino acids; 12 of these are produced within cells. b. A protein’s function is determined by its sequence of amino acids. (i) The sequence of DNA bases taken three at a time (a triplet) ultimately specifies which amino acids are to be used to synthesize a protein.

4. Protein synthesis occurs at the ribosomes. a. The first step is called transcription. This starts in the nucleus as a complementary strand of messenger RNA (mRNA) is produced from the DNA strand. (i) mRNA differs from DNA in that it is single-stranded, contains a different type of sugar, and has uracil (U) instead of thymine. b. The second step, translation, occurs at the ribosomes. (i) Here, the mRNA strand is “read” by the ribosomes three bases (one codon) at a time. (ii) This step requires the carrier molecule, transfer RNA (tRNA). (iii) Each tRNA has the ability to bind to one amino acid. (iv) If a DNA base or sequence of bases is changed through mutation, some proteins may not be made or may be defective.

IV. What Is a Gene?

A. A gene is the sequence of DNA bases responsible for the synthesis of a protein, a portion of a protein, or any functional product (e.g. RNA).

1. New genetic research indicates that we must modify the above definition, since DNA is known to also code for RNA and DNA nucleotides.

2. Sequencing the human genome revealed that humans have about 25,000 genes; yet we produce as many as 90,000 proteins.

B. Gene action is complex, since not all segments of DNA are expressed during protein synthesis.

1. Exons are DNA segments transcribed and expressed in protein synthesis.

2. Introns are noncoding DNA segments transcribed but deleted before transcription.

V. Regulatory Genes A. Regulatory genes produce proteins that influence the activity of other genes. a. Homeobox genes are an evolutionarily ancient group of regulatory genes that directs the development of the overall body plan and the segmentation of body tissues. (i) Homeobox genes have been maintained conservatively much throughout evolutionary history. (ii) One type of homeobox genes are Hox genes, important to the development of the spinal and thoracic regions.

VI. Cell Division A. Cell division produces new cells.

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B. At the beginning of cell division DNA becomes tightly coiled and is visible as a set of discrete structure, or chromosomes.

1. Chromosomes are composed of DNA and protein and each species has a specific number of chromosomes: humans have 46. a. There are two types of chromosomes: (i) Autosomes carry genetic information that governs all physical characteristics except primary sex determination. (ii) Sex chromosomes determine sex determination: (a) Female mammals normally have two X chromosomes, and males normally have one X and one Y chromosome.

2. Mitosis is cell division in somatic cells. a. Human somatic cells contain 46 double-stranded chromosomes in the early stages of mitosis. b. Chromosomes line up along the center of the cell and are pulled apart at the centromere. (i) The result is a genetically identical daughter cell with the full complement of DNA, or 46 chromosomes.

3. Meiosis produces reproductive cells (gametes). a. Meiosis has two divisions: a reduction division and a second cell division. (i) In the first division, pairs of homologous chromosomes line up at the center of the cell. As division proceeds, the double-stranded chromosomes are not pulled apart; rather, the members of pairs migrate to opposite sides of the cell. The result is two cells, each of which contains 23 double-stranded chromosomes. This is also called recombination or crossing over. (ii) In the second division, the 23 double-stranded chromosomes align at the center of the cell and then are pulled apart. This reduction is similar to mitosis. (i) The result is four daughter cells, each with 23 single-stranded chromosomes. b. The Evolutionary Significance of Meiosis (i) Meiosis (and sexual reproduction) increases genetic variation in populations. (ii) Recombination between partner chromosomes increases the genetic uniqueness of individuals that are not clones of one another. c. Problems with Meiosis (i) Failure of homologous chromosomes or chromosome strands to separate during meiosis is termed nondisjunction. (a) Nondisjunction leads to trisomy. (b) Trisomy 21 (Down syndrome) occurs when there are three copies of chromosome 21 present in the individual. (c) This occurs in about 1/1,000 live births. (ii) Nondisjunction may also occur in sex chromosomes, causing sterility, some mental impairment, and other problems.

VII. New Frontiers A. The discovery of DNA’s structure and function has revolutionized biology.

1. The polymerase chain reaction (PCR) technique was developed in 1986 and is used to analyze from small segments of DNA. a. With PCR, very small samples of DNA can be examined for the patterns of repeated DNA sequences unique to each individual. This process is called DNA fingerprinting and is in forensic science and medicine.

2. Recombinant DNA technology is used to transport genes from one species into another. a. Dolly, the sheep, was cloned in 1997. She was euthanized in February 2003 at the age of six years due to health problems she developed.

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3. The single most important advance in genetics has been the progress made by the Human Genome Project (HGP). a. The HGP begun in 1990, with attempts to sequence the entire human genome. In 2003 the project was successfully completed. b. As of now, the genomes of hundreds of species have been sequenced including mice, chimpanzees, and rhesus macaques. c. In May, 2010 the Neandertal genome was sequenced d. Scientists have created a functional, synthetic bacterial genome.

Key Terms and Concepts Amino acids, p. 54 Autosomes, p. 61 Chromosomes, p. 59 Clones, p. 65 Codons, p. 55 Complementary, p. 53 Cytoplasm, p. 50-51 DNA (deoxyribonucleic acid), p. 50 Enzymes, p. 53 Exons, p. 57 Gametes, p. 51 Gene, p. 57 Genome, p. 57 Hemoglobin, p. 54 Homeobox genes, p. 58 Hormones, p. 54 Human Genome Project, p. 68 Introns, p. 57 Meiosis, p. 62 Messenger RNA (mRNA), p. 54 Mitochondria, p. 50-51 Mitochondrial DNA (mtDNA), p. 50-51 Mitosis, p. 62 Molecules, p. 50 Mutation, p. 55 Noncoding DNA, p. 57 Nucleotides, p. 52 Nucleus, p. 50 Polymerase chain reaction (PCR), p. 66 Protein synthesis, p. 50-51 Proteins, p. 50 Recombination, p. 65 Regulatory genes, p. 58 Replicate, p. 53 Ribosomes, p. 50-51 RNA (ribonucleic acid), p. 50-51 Sex chromosomes, p. 61 Copyright © 2017 Cengage Learning. All Rights Reserved.

Somatic cells, p. 51 Transfer RNA (tRNA), p. 55 Zygote, p. 51 Lecture Suggestions 1. Discuss the importance of genetics and its application to many areas of our lives such as health, reproduction, and food production. Consider the ways that health services (and insurance) are changing to accommodate advances in genetics. Discuss with students the ethics of genetics information.

2. Elaborate on cell function and the specialization of cells. Point out that although all cells carry the same DNA, much of the DNA is “switched off” during fetal development. What new frontiers might this afford us in the future?

3. Elaborate on the universal nature of the genetic code to emphasize the concept of biological continuity. Reinforce the fact that chimpanzees and humans share about 98 percent of their DNA. 4. Provide examples of other autosomal trisomies, such as trisomy 13 (Patau syndrome), and trisomy 18 (Edwards syndrome). Present these as case studies in the class.

Internet Exercises 1. Watson and Crick’s original 1953 article, A Structure for Deoxyribose Nucleic Acid, can be found at http://www.nature.com/nature/dna50/watsoncrick.pdf. Read the article and list the most important points that are made by the authors.

2. An interesting website on the human genome and cells is located at: https://unlockinglifescode.org/learn/the-animated-genome. There are short animated introductory clips explaining DNA and also cell structure that may be useful in class, especially with beginning level students.

3. For a review of many of the concepts presented in the chapter, see the video clip “From Cell to DNA” at http://sciencenetlinks.com/tools/from-cell-to-dna/.

4. Read, A Draft Sequence of the Neandertal Genome, Richard Green et al., 2010, http://www.sciencemag.org/content/328/5979/710.full.

Multiple Choice Questions 1. Cells: a. are the basic units of life. b. usually do not have DNA. c. only have a nucleus and no cytoplasm. d. are only inherited from one parent. e. originated on earth approximately 5 million years ago.

ANS: a REF: Cells 2. Basic units of the DNA molecule composed of a sugar, phosphate, and one of four DNA bases is called a(n): a. protein. b. enzyme. c. intron. d. chromosome. e. nucleotide.

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ANS: e REF: From DNA to Protein 3. Somatic cells are not: a. one type of eukaryotic cell. b. also known as gametes. c. the cellular components of tissue. d. basically all the cells in the body except those involved in reproduction. e. those that make up tissues e.g., muscles and the brain.

ANS: b REF: Cells 4. Ribosomes are: a. the sex chromosomes. b. the gametes. c. found only in prokaryotes. d. only present when the cell divides. e. important to protein synthesis.

ANS: e REF: Cells 5. The two basic types of cells are somatic cells and: a. zygotes. b. gametes. c. autosomes. d. polar bodies. e. organelles.

ANS: b REF: Cells 6. Gametes: a. are basic units of the DNA molecule composed of sugar. b. are also called zygotes. c. transmit genetic information from parent to offspring. d. can make copies of all other types of cells. e. are important structural components of the body.

ANS: c REF: Cells 7. A zygote: a. is formed by the union of two somatic cells. b. has only half the full complement of the necessary genetic material. c. is part of a nucleotide. d. undergoes meiosis. e. has the potential to develop into a new individual.

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ANS: e REF: Cells 8. The structure within the cytoplasm that converts energy is called: a. prokaryotes. b. eukaryotes. c. mitochondria. d. messenger RNA (mRNA). e. transfer RNA (tRNA).

ANS: c REF: Cells 9. All of the following is true of genetics except it: a. is required in only a few of the specialty areas of biological anthropology. b. unifies the various subdisciplines of biological anthropology. c. is the study of how genes work. d. is an approach that explains how traits are inherited across generations. e. is not a specialty for most physical anthropologists.

ANS: a REF: Introduction 10. Which of the following nitrogenous bases in not found in DNA? a. Uracil b. Guanine c. Thymine d. Adenine e. Cytosine ANS: a REF: From DNA to Protein 11. The DNA base adenine always pairs with which other DNA base? a. Guanine b. Thymine c. Cytosine d. Uracil e. Mitochondria ANS: b REF: From DNA to Protein 12. Enzymes are: a. specialized proteins. b. reproductive cells. c. a semifluid substance in the nucleus of the cell. d. always produced outside the body. e. in the formation of a double helix.

ANS: a

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REF: From DNA to Protein 13. Which component of red blood cells is responsible for oxygen transport? a. Valine b. Hemoglobin c. Proline d. The cell membrane e. The ribosomes ANS: b REF: From DNA to Protein 14. Which of the following statements concerning RNA is false? a. It contains the base uracil instead of thymine. b. It is single-stranded. c. It contains the same sugar as found in DNA. d. It is able to pass through the nuclear membrane. e. It is involved in the synthesis of proteins.

ANS: c REF: From DNA to Protein 15. Which of the following statements is false? a. Proteins are composed of amino acids. b. The first step in protein synthesis is translation. c. The number and sequence of amino acids determines protein function. d. Proteins are manufactured by the ribosomes. e. The sequence of amino acids in a protein is ultimately determined by the sequence of DNA bases.

ANS: b REF: From DNA to Protein 16. In protein synthesis, the process called transcription is which of the following? a. Manufacture of tRNA b. Assembly of polypeptide chains c. Formation of a mRNA molecule d. Production of amino acids e. Manufacture of ribosomal RNA ANS: c REF: From DNA to Protein 17. What do we call the complete sequence of DNA bases that specifies the order of amino acids in an entire protein or portion of protein, or any functional product? a. Helix b. Codon c. Polypeptide d. Amino acid e. Gene

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ANS: e REF: What Is a Gene?

18. What is the name for DNA segments transcribed into mRNA and coded for specific amino acids? a. Exons b. Codons c. Mutons d. Alleles e. Proteins ANS: a REF: What Is a Gene?

19. The two strands of a chromosome are joined at a constricted area called the: a. autosome. b. ribosome. c. centromere. d. nucleotide. e. cytoplasm.

ANS: c REF: Cell Division 20. Chromosomes are: a. made up of DNA and proteins. b. visible during all stages of cell division. c. composed only of mRNA. d. indiscrete structures. e. occur singularly.

ANS: a REF: Cell Division 21. Homeobox genes are associated with all of the following except: a. they interact with other types of genes to determine characteristics. b. they are a type of regulatory gene. c. there are several different kinds of homeobox genes. d. they are highly conserved and maintained over evolutionary history. e. they vary greatly from species to species.

ANS: e REF: Regulatory Genes 22. Autosomes: a. happen only in cases where a genetic deficiency occurs. b. carry genetic information that determine the individual’s sex. c. are found within gametes only. d. carry genetic information influencing all physical characteristics except primary sex determination. e. do not carry genetic information.

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ANS: d REF: Cell Division 23. How many chromosomes occur in a normal human somatic cell? a. 44 b. 48 c. 46 d. 53 e. 23 ANS: c REF: Cell Division 24. How many chromosome pairs occur in a normal human somatic cell? a. 24 b. 23 c. 26 d. 25 e. 46 ANS: b REF: Cell Division 25. What are the X and Y chromosomes called? a. Autosomes b. Gametes c. Centromeres d. Sex chromosomes e. Karyotypes ANS: d REF: Cell Division 26. The Y chromosome: a. is found in both sexes; males have two, and females have one. b. influences numerous characteristics in addition to sex determination. c. can be inherited from either parent. d. carries a gene that causes a fetus to develop as male. e. causes a fetus to develop as female if two are present.

ANS: d REF: Cell Division 27. Which of the following statements is true of mitosis? a. The process requires only one cell division to be complete. b. There are two cell divisions before the process is complete. c. It results in gamete formation. d. Crossing-over occurs during mitosis between homologous chromosomes. e. Homologous chromosomes come together as pairs during mitosis.

ANS: a

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REF: Cell Division 28. After mitosis, daughter cells contain the same amount of DNA as in the original cell. What is this due to? a. Protein synthesis b. Recombination c. Pairing of homologous chromosomes d. Meiosis e. DNA replication ANS: e REF: Cell Division 29. Meiosis: a. is the cell division process in somatic cells. b. replaces cells during growth and development. c. permits healing of injured tissue. d. is the cell division in specialized cells in ovaries and testes. e. involves two divisions and results in six daughter cells.

ANS: d REF: Cell Division 30. Which of the following statements is false regarding the process of meiosis? a. Meiosis produces gametes. b. Meiosis produces daughter cells with half the original amount of DNA found in the original cell. c. There are two cell divisions. d. Meiosis produces daughter cells with the same amount of DNA found in the original cell. e. After recombination, each chromosome contains some new genetic combinations.

ANS: d REF: Cell Division 31. Hox genes are primarily associated with determining the characteristics of what part of the body? a. Heart (circulatory system) b. Spine (vertebrae) c. Limbic system d. Endocrine system e. Brain ANS: b REF: Regulatory Genes 32. Which of the following statements is false? a. Nondisjunction occurs when homologous chromosomes fail to separate. b. Nondisjunction occurs when strands of the same chromosome fail to separate. c. Nondisjunction can result in a daughter cell with an extra chromosome. d. Nondisjunction can result in a daughter cell completely lacking a chromosome. e. Nondisjunction occurs only in mitosis.

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ANS: e REF: Cell Division 33. Which of the following is incorrect? Trisomy 21: a. is only one of several examples of an abnormal number of autosomes. b. is caused by nondisjunction. c. is caused by having three copies of chromosome 21. d. occurs in 1 out of 10,000 births. e. is associated with paralysis of limbs.

ANS: e REF: Cell Division 34. Scientists use _______ to produce many copies of small DNA fragments, such as those obtained at crime scenes or from fossils. a. transcription b. polymerase chain reactions c. nondisjunction d. trisomies e. random assortment of alleles ANS: b REF: New Frontiers 35. What was a major goal of the Human Genome Project? a. Facilitate human cloning b. Map the chromosomes of every human on the planet c. Sequence the entire human genome d. Trace evolutionary relationships among primates e. Prevent overpopulation ANS: c REF: New Frontiers

True/False Questions 1. A eukaryotic cell is composed of carbohydrates, lipids, and proteins but lacks nucleic acids.

ANS: False REF: Cells 2. Mitochondrial DNA has the same molecular structure and function as nuclear DNA found in the nucleus.

ANS: False REF: Cells 3. The discovery of the structure of DNA dates back to the late 1700s.

ANS: False REF: From DNA to Proteins

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4. The structure of DNA can be described as a triple helix.

ANS: False REF: From DNA to Proteins 5. A triplet is a series of three mRNA bases.

ANS: True REF: From DNA to Protein 6. Transfer RNA forms a copy of the DNA molecule during translation.

ANS: False REF: From DNA to Protein 7. The process of translation during protein synthesis occurs at the ribosomes.

ANS: True REF: From DNA to Protein 8. Regulatory genes produce enzymes and other proteins that either switch on or turn off other segments of DNA. ANS: True REF: Regulatory Genes 9. Meiosis occurs only in ovaries.

ANS: False REF: Cell Division 10. The result of nondisjunction is that none of the daughter cells will receive any chromosomes.

ANS: False REF: Cell Division 11. Nondisjunction can occur in the autosomes but never occurs in the sex chromosomes.

ANS: False REF: Cell Division 12. The Human Genome Project was successfully completed in 1952.

ANS: False REF: New Frontiers

Short Answer Questions 1. Describe the structure of the DNA molecule in as much detail as you can.

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ANS: It is a double-stranded molecule held together by a series of four matching bases.

REF: Cells 2. What is a regulatory gene?

ANS: It is genes that influence the activity of other genes. They direct embryonic development and are involved in physiological processes throughout life.

REF: Regulatory Genes 3. What are the two steps in protein synthesis?

ANS: The two steps are transcription and translation (or decoding).

REF: From DNA to Protein 4. Compare and contrast the processes and end products of mitosis and meiosis.

ANS: In mitosis there is a simple division that produces two daughter cells, each of which contains 46 chromosomes. In meiosis there are two divisions that result in four cells, each with only half the original number of chromosomes.

REF: Cell Division 5. What is the evolutionary significance of meiosis?

ANS: It increases genetic variation in populations and prevents cloning.

REF: Cell Division 6. What causes nondisjunction? Give one example of nondisjunction.

ANS: Nondisjunction occurs when chromosomes or strands do not separate during either of the two divisions. One of the daughter cells gets two copies of the affected chromosome and the other gets none. Trisomy 21 is one of the best-studied examples of nondisjunction.

REF: Cell Division 7. What is polymerase chain reaction and why is it important in genetics?

ANS: PCR is a method of producing thousands of copies of a DNA sample. This allows scientists many examples of DNA to analyze and to use for experiments.

REF: New Frontiers 8. Give two examples of how the field of genetics has revolutionized biological science.

ANS: Some examples are development of polymerase chain reaction, the Human Genome Project, and sequencing the Neandertal genome.

REF: New Frontiers

Essay Questions 1. Humans and chimpanzees share about 98 percent of their DNA. What might be the role of regulatory genes in producing the anatomical differences between these two lineages?

ANS: Will vary

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REF: Regulatory Genes 2. Discuss whether it is possible for a human to have the following combinations of sex chromosomes: XYY; XO (only one X and no Y); XXX. ANS: Will vary REF: Cell Division 3. The definition of gene is currently the subject of some debate. What is the central focus of the debate and what is the reason for the conflicting meanings?

ANS: Will vary REF: What Is a Gene?

4. The progress made in genetics by the Human Genome Project is significant. What was the goal of the project and what is the potential for anthropologists, given that the genomes of other species are being studied?

ANS: Will vary Ref: New Frontiers

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CHAPTER 4: HEREDITY AND EVOLUTION Chapter Outline I.

Introduction A. It was not until the 20th century that scientists understood how selective breeding could increase the frequency of desirable characteristics.

B. The genetic principles described by Mendel form the basis of modern genetics.

1. Anne Boleyn, mother of England’s Queen Elizabeth I and wife of Henry VIII had an extra little finger; a historic example of polydactyly.

2. The predominant belief centered on the blending of parental traits in the offspring, starting with the Greek philosophers; even Darwin held this belief.

II. The Genetic Principles Discovered by Mendel A. Historically, there have been examples of the effects of genetics, although the field of genetics did not emerge until the 19th century.

B. Gregor Mendel (1822-1884) developed his theory of heredity while working with garden pea hybrids.

C. Segregation 1. The parental (P) generation was crossed to produce the first filial (F1) generation. a. The F1 generation did not have intermediate traits. b. The F1 generation was then crossed to produce the F2 generation. (i) One expression of the trait, shortness of the stem, for example, disappeared in the F1 generation but reappeared in the F2 generation. (ii) The expression present in the F1 generation occurred more often in the F2 generation (in a 3:1 ratio). c. Mendel concluded that discrete units, occurring in pairs and separating into different sex cells, must control the traits. (i) This is Mendel’s first principle of inheritance, the principle of segregation.

D. Dominance and Recessiveness 1. Mendel used these terms to account for the fact that the expression of one (recessive) trait in the F1 generation was masked by the expression of the other (dominant) trait. These principles of dominance and recessiveness are important concepts in genetics today. a. Variations of genes at a locus are termed alleles. b. Plant height in peas (but not in all plants) is controlled by two alleles at one locus. (i) When two copies of the same allele occur at one locus, the individual is homozygous. (ii) When two different alleles are paired at the same locus, the individual is heterozygous. c. The genotype refers to an organism’s entire genetic makeup. d. The phenotype is the observed physical manifestation of genes.

2. A Punnett square can be used to predict the proportions of F2 phenotypes and genotypes.

E. Independent Assortment 1. Mendel also demonstrated that different characteristics aren’t necessarily inherited together by showing that plant height and seed color are independent of each other. a. Mendel stated this relationship as the principle of independent assortment. (i) According to this principle, the genes that code for different traits (e.g. plant height and seed color) sort out independently of each other during gamete formation.

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(ii) Genes that control plant height and seed color are located on different, non partner chromosomes, and during meiosis, the chromosomes travel to newly forming cells independently of each other in a process known as random assortment.

III. Mendelian Inheritance in Humans A. Mendelian traits are also called discrete traits, controlled by alleles at only one genetic locus (or, in some cases, two or more very closely linked loci).

B. There are over 20,000 human characteristics inherited according to Mendelian principles.

1. Most Mendelian traits do not have visible phenotypic expressions; the majority of the traits are biochemical in nature.

2. Genetic disorders result from harmful alleles inherited in Mendelian fashion.

3. Traits may be inherited either as dominant or recessive alleles. a. Dominant alleles cause a number of genetic disorders. b. Recessive conditions are typically associated with the lack of a substance, usually an enzyme. For a person to have a recessive disorder, he/she must have two copies of the recessive allele that causes it. (i) Individuals who have one copy of the harmful recessive allele are unaffected, but can pass that allele onto offspring. They are termed carriers. c. Blood groups provide one of the best examples of Mendelian traits. (i) Alleles determine a person’s blood type by coding for the production of antigens. d. Codominance exists where two different alleles are present and both are expressed.

C. There are misconceptions regarding dominance and recessiveness: 1. Dominance and recessiveness are not all-or-nothing situations.

2. Several recessive alleles are known to have effects on the phenotype at the biochemical level, although they are not usually detectable through simple observation.

3. Dominant alleles are not “stronger,” “better,” or more common than recessive alleles.

IV. Polygenic Inheritance refers to traits that are influenced by alleles at two or more loci.

A. For example, skin coloration is determined by melanin, a pigment produced by specialized cells called melanocytes.

1. The alleles coding for melanin production have additive effects.

2. The effect of multiple alleles at several loci produces continuous variation in skin tone. a. One single, highly-conserved gene (MC1R) with two alleles makes a greater contribution to melanin production than some other melanin-producing genes. b. There are at least four other pigmentation genes.

B. Much of the variation in human phenotypes used in traditional racial classifications is produced by polygenic, not Mendelian, traits.

1. Most polygenic traits can be measured on a scale, hence are continuous traits.

2. Many Mendelian traits have known loci. However, polygenic traits cannot yet be traced to specific loci.

V. Genetic and Environmental Factors A. For polygenic traits, many aspects of the phenotype are influenced by genetic-environmental interactions.

1. For many characteristics, it is not possible to identify the specific environmental components that influence the phenotype.

B. Mendelian traits are less likely to be influenced by the environment; yet even for polygenic characteristics, Mendelian principles still apply at individual loci.

VI. Mitochondrial Inheritance A. mtDNA is transmitted to the offspring only from the mother.

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1. Because mtDNA is inherited from only one parent, meiosis and recombination do not occur.

2. This means that all the variation in mtDNA among individuals is caused by mutation, which makes mtDNA extremely useful for studying genetic change over time.

B. All the variation in mtDNA among individuals is caused by mutation (mtDNA mutation rates have been used to construct evolutionary relationships between primate species and between living human populations).

VII. Modern Evolutionary Theory A. Modern evolutionary theory has its roots in the principles of natural selection formulated by Darwin and Wallace, plus the rediscovery of Mendelian principles of inheritance. The competing explanations of evolution offered by mutationists and selectionists were synthesized into a single theory in the mid-1930s.

B. The Modern Synthesis is the comprehensive theory of evolution that incorporates two processes: variation and natural selection.

1. The production and redistribution of variation.

2. The process of natural selection acting on this variation.

C. A Current Definition of Evolution is defined as a change in allele frequency from one generation to the next.

1. Allele frequencies are indicators of the genetic makeup of a population, the members of which share a gene pool.

2. Short-term evolutionary changes, such as allele frequency changes from one generation to the next, are termed microevolution.

3. Long-term evolutionary effects that are evident in the fossil record are termed speciation, or macroevolution.

VIII. Factors That Produce and Redistribute Variation A. Mutations are changes in alleles. Point mutation is the substitution of one single DNA base for another, which can cause the allele to change.

1. Mutations must occur in the gametes (sperm or egg) to have evolutionary consequences.

2. Mutation rates tend to be low, and mutations alone tend to have little impact on changes in allele frequencies. a. Evolutionary changes can occur rapidly when mutations are coupled with natural selection. b. Mutations are the only way to produce new genes evolutionarily.

B. Gene Flow is the exchange of genes between populations.

1. Population movements (and the resulting exchange of genes) have been very high during the past 500 years. a. Gene flow between human populations helps to explain why human speciation has been rare during the past 1 million years C. Genetic Drift and Founder Effect are caused by random alterations of allele frequencies in populations, and are both tied to population size.

1. Genetic drift occurs solely because the population is small and an allele may completely disappear because it is not passed on to offspring.

2. Founder effect is a particular kind of drift that may occur when a small founding population colonizes a new area or when a large population is reduced to a much smaller size through war, famine, disease, or other factors. a. The loss of genetic diversity is termed a genetic bottleneck. b. Numerous species are known to have passed though genetic bottlenecks, including the cheetah and the California condor.

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3. Both gene flow and genetic drift can produce evolutionary changes, yet usually these are microevolutionary changes. Natural selection is necessary to produce macroevolutionary changed such as the emergence of a new species.

D. Recombination is when paired chromosomes exchange DNA during meiosis and genes sometimes find themselves in different genetic environments.

1. This does not cause evolution, but it provides genetic combinations upon which natural selection can act.

IX.

Natural Selection Is Directional and Acts on Variation A. Natural selection acts on variation produced by mutation, gene flow, genetic drift, and recombination.

1. Directional changes in allele frequencies are a function of the environmental context.

2. If the environment changes, selection pressures change, and ultimately, allele frequencies also change. Such a shift in allele frequencies is called adaptation.

B. The best example of natural selection in human populations involves the allele for hemoglobin S. 1. The HbS mutation occurs at a low frequency in all human populations.

2. In some populations, especially in western and central Africa, the HbS allele occurs in frequencies approaching 20 percent. a. The geographical correlation between the distribution of malaria and high frequencies of the HbS allele indicates a biological relationship between the two. b. Sickle-cell trait results when an individual inherits only one copy of the Hbs allele. c. Sickle-cell anemia trait results from inheriting two copies of the Hbs allele. d. Sickle-cell anemia has numerous manifestations, but basically, the abnormal hemoglobin S reduces the ability of red blood cells to transport oxygen throughout the body.

X. Review of Genetics and Evolutionary Factors A. The evolutionary process occurs at four different levels.

1. Mutations of the DNA in the gametes (the molecular level).

2. The chromosomes assort during meiosis and are passed on to the offspring (the cellular level).

3. The individual is subject to natural selection (the level of the individual).

4. Populations are composed of individuals, and evolution is said to occur when allele frequencies change (the level of the population). a. Genetic drift and gene flow may act to change allele frequencies in populations.

Key Terms and Concepts Allele frequency, p. 85 Alleles, p. 77 Antigens, p. 79 Codominance, p. 79 Dominant, p. 77 Founder effect, p. 87 Gene flow, p. 86 Gene pool, p. 85 Genetic drift, p. 87 Genotype, p. 77 Heterozygous, p. 77 Homozygous, p. 77 Hybrids, p. 75 Locus, p. 77

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Macroevolution, p. 86 Mendelian traits, p. 79 Microevolution, p. 86 Modern Synthesis, p. 85 Phenotypes, p. 78 Pigment, p. 82 Polygenic, p. 81 Population, p. 85 Principle of independent assortment, p. 78 Principle of segregation, p. 76 Random assortment, p. 78 Recessive, p. 76-77 Selective breeding, p. 74 Sickle-cell anemia, p. 90 Sickle-cell trait, p. 90 Variation, p. 85

Lecture Suggestions 1. Illustrate Mendelian principles in your class by calculating the frequencies for various Mendelian traits, such as hitchhiker’s thumb or earlobe form. Then, demonstrate the nature of continuous traits by calculating stature or forearm length. The data can then be used to illustrate the different statistical approaches to Mendelian versus polygenic traits.

2. Explore genetic bottlenecking by illustrating it with in-depth case studies of those species currently affected, such as the cheetah, and those that have passed through it, such as the California condor, California elephant seals, etc. Trace the process of re-introduction and wildlife management of the species. What challenges do humans face as they attempt to return and restore a species?

3. Have students construct their own family pedigree for a particular Mendelian trait. Again, the ABO blood groups are simple to explore. Even if they do not know their own blood type, they may be able to determine their parents’ and siblings’ types and calculate their own possibilities and/or probabilities using Punnett squares.

4. Explore advances in the field of genetics and genetic testing which permit more accurate diagnosis of individual carrier status. Point out that these advances will eventually eliminate the need for pedigree analysis as more accurate methods of diagnosis become available.

Internet Exercises 1. Go to http://www.appalachianhistory.net/2010/06/blue-fugates-of-kentucky.html and read about the Fugates of Kentucky. What genetic condition is responsible for their remarkable skin color?

2. At the website http://www.nature.com/scitable/topicpage/gregor-mendel-and-the-principles-ofinheritance-593 there are numerous explanations and follow-up activities associated with Mendelian genetics.

3. There is an excellent in-depth article on evolution and evolutionary principles at http://www.talkorigins.org/faqs/faq-intro-to-biology.html.

4. PBS has an engaging website at http://www.pbs.org/wgbh/evolution/library/faq/cat01.html that includes an overview of evolution and also follow-up activities. Students may find these helpful as a review and deeper exploration into the topic.

Multiple Choice Questions 1. Gregor Mendel is known for which of the following? a. He developed theories of evolutionary change, such as natural selection.

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b. c. d. e.

He discovered the structure of the DNA molecule.

He studied polygenic characteristics that are influenced by several genetic loci.

He discovered the fundamental principles of how traits are inherited.

He developed the theory of inheritance of acquired characteristics.

ANS: d REF: Introduction 2. How do the basic principles of inheritance, identified by Mendel in plants, differ from those in humans? a. They are simpler. b. Plants don’t have alleles. c. There are no differences since the basic principles are the same. d. There are no Mendelian traits in humans. e. The number of chromosomes is different; therefore, genetic principles vary.

ANS: c REF: Introduction 3. When Mendel crossed true breeding tall and short parent plants (producing first generation), what was produced? a. All the offspring were tall. b. Half the offspring were tall, the other half were short. c. All the offspring were short. d. The offspring were intermediate in height relative to the two parent plants. e. About 90 percent were tall, but the rest were short.

ANS: a REF: The Genetic Principles Discovered by Mendel 4. In Mendel’s experiments, what was the ratio of tall to short plants in the F2 generation? a. 15 to 1 b. 3 to 1 c. ½ tall, ½ short d. 4 to 1 e. 5 to 1 ANS: b REF: The Genetic Principles Discovered by Mendel 5. Which statement concerning the F1 plants in Mendel’s experiments with height is false? a. They were hybrids. b. Some of them were heterozygous for the traits in question. c. Their parents were all tall. d. All F1s displayed the dominant trait in their phenotype. e. All F1s displayed the recessive trait in their phenotype.

ANS: e REF: The Genetic Principles Discovered by Mendel 6. A person who is homozygous recessive at a locus has which of the following?

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a. b. c. d. e.

Two copies of the recessive allele Two copies of the dominant allele An autosomal trisomy A recessive allele on the X chromosome only A recessive allele on the Y chromosome only

ANS: a REF: The Genetic Principles Discovered by Mendel 7. The position on a chromosome where a given gene occurs is called a(n): a. Mendelian trait. b. phenotype. c. genotype. d. locus. e. allele.

ANS: d REF: The Genetic Principles Discovered by Mendel 8. Mendelian traits are also called: a. discrete traits. b. indiscrete traits. c. continuous traits. d. heterozygous traits. e. homozygous traits.

ANS: a REF: Mendelian Inheritance in Humans 9. What is an individual’s actual genetic make-up called? a. Phenotype b. Homozygosity c. Recessiveness d. Phenotypic ratio e. Genotype ANS: e REF: The Genetic Principles Discovered by Mendel 10. According to the principle of independent assortment there is a __________chance that any tall pea plant will produce either yellow or green peas. a. 0 percent b. 25 percent c. 50 percent d. 75 percent e. 100 percent ANS: c REF: The Genetic Principles Discovered by Mendel 11. What is the term used to refer to the observable, physical expression of genotypes?

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a. b. c. d. e.

Genotype Phenotype Phenotypic ratio Genotypic ratio Independent assortment

ANS: b REF: The Genetic Principles Discovered by Mendel 12. In general, Mendelian traits: a. are governed by more than one genetic locus. b. occur only in some people. c. are always dominant. d. are governed by one genetic locus. e. are always recessive.

ANS: d REF: The Genetic Principles Discovered by Mendel 13. Gregor Mendel: a. won the Nobel Prize for his discoveries. b. was formally trained as a geneticist. c. did not know about chromosomes. d. was a professor at the University of Vienna. e. never published his work.

ANS: c REF: The Genetic Principles Discovered by Mendel 14. The ABO blood type system consists of ______ alleles. a. 6 b. 4 c. 3 d. 2 e. 5 ANS: c REF: Mendelian Inheritance in Humans 15. Which of the following is not a polygenic trait? a. Stature b. Skin color c. Eye color d. ABO blood type e. Hair color ANS: d REF: Polygenic Inheritance 16. What is it called when a person possesses two different alleles at the same locus, and both alleles are expressed in the phenotype?

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a. b. c. d. e.

Recessiveness Codominance Dominance Homozygosity X-linkage

ANS: b REF: Mendelian Inheritance in Humans 17. What is type AB blood an example of? a. Codominance b. Blending c. Recessiveness d. Dominance e. Polygenic inheritance ANS: a REF: Mendelian Inheritance in Humans 18. How many ABO phenotypes (blood types) are there? a. 4 b. 2 c. 3 d. 6 e. 1 ANS: a REF: Mendelian Inheritance in Humans 19. Mendelian traits are described as discrete, or discontinuous, because: a. their phenotypic expressions overlap. b. their phenotypic expressions do not fall into clearly defined categories. c. their genotypic expressions overlap. d. they are controlled by alleles at four different loci. e. they are controlled by alleles at a single locus.

ANS: e REF: Mendelian Inheritance in Humans 20. In a hypothetical situation, B is the allele that causes brachydactyly. If a man who has normal fingers (bb) and a woman with brachydactyly (Bb) have children, what proportion of these children would you expect to have normal fingers? (Hint: Use a Punnett square). a. None b. All c. 1/4 d. 3/4 e. 1/2 ANS: e REF: The Genetic Principles Discovered by Mendel

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21. At a hypothetical locus, a man’s genotype is Aa. What proportion of his gametes would be expected to receive the A allele? a. All b. ½ c. ¾ d. ¼ e. None ANS: b REF: The Genetic Principles Discovered by Mendel 22. Two people (both heterozygotes) are able to taste a chemical substance called PTC. The ability to taste PTC is caused by a dominant allele (T). The inability to taste PTC is caused by a recessive allele (t). What proportion of their children would be expected to have the ability to taste PTC? a. 3/4 b. 1/2 c. All d. 1/4 e. 2/3 ANS: a REF: The Genetic Principles Discovered by Mendel 23. Polygenic traits are also called: a. indiscrete. b. discrete. c. continuous. d. bimodal. e. Mendelian.

ANS: c REF: Polygenic Inheritance 24. Scientists have used mitochondrial inheritance as a means to study all of the following except: a. ancestral relationships in the human lineage. b. development of continuous Mendelian traits. c. evolutionary relationships between species. d. genetic variability among individuals. e. genetic variability within populations.

ANS: b REF: Mitochondrial Inheritance 25. Which of the following is not inherited in a Mendelian fashion? a. Huntington Disease b. Albinism c. Cleft chin d. Tay-Sachs disease e. Skin color ANS: e

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REF: Polygenic Inheritance 26. Which of the following types of traits are governed by more than one genetic locus? a. Polygenic b. Dominant c. Mendelian d. Recessive e. Pleiotropic ANS: a REF: Polygenic Inheritance 27. Which statement concerning polygenic traits is not true? a. They are governed by more than one genetic locus. b. Their expression is often influenced by genetic/environmental interactions. c. The alleles have an additive effect on the phenotype, intensifying the genes. d. They are continuous traits. e. The most frequently discussed are skin, hair, and eye color.

ANS: c REF: Polygenic Inheritance 28. Polygenic traits: a. are discrete. b. have a continuous range of expression. c. are controlled by only one genetic locus. d. include the ABO blood type system and cystic fibrosis. e. are also called Mendelian traits.

ANS: b REF: Polygenic Inheritance 29. What does each mitochondrion contain? a. Nuclear DNA b. 46 chromosomes c. An X but never a Y chromosome d. Several copies of a ring-shaped DNA molecule, or chromosome e. A Y but never an X chromosome ANS: d REF: Mitochondrial Inheritance 30. Evolution can be described as a two-stage process that includes which of the following? a. Mutation and polygenic inheritance only b. Independent assortment and recombination only c. Recombination followed by mutation d. Production of a fixity of species e. Production and redistribution of variation ANS: e REF: Modern Evolutionary Theory

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31. Evolution can be most succinctly defined as: a. the appearance of a new species. b. the change from one species to another in one generation. c. the change in allele frequency from one generation to the next. d. any type of genetic mutation. e. genetic drift.

ANS: c REF: Modern Evolutionary Theory 32. What is the only source of new genetic material in any population? a. Mutation b. Genetic drift c. Founder effect d. Migration e. Natural selection ANS: a REF: Factors that Produce and Redistribute Variation 33. What produces completely new alleles at a locus? a. Natural selection b. Recombination c. Mutation d. Migration e. Genetic drift ANS: c REF: Factors that Produce and Redistribute Variation 34. In order for a mutation to be passed on to offspring, the mutation must: a. occur in a gamete. b. be beneficial. c. occur in a somatic cell. d. result in additional chromosomes. e. have negative evolutionary consequences.

ANS: a REF: Factors that Produce and Redistribute Variation 35. What is gene flow defined as? a. Production of new alleles b. Production of new genetic material c. Chance loss of alleles in a population d. Exchange of genes between populations e. Differential reproductive success of individuals ANS: d REF: Factors that Produce and Redistribute Variation

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36. Genetic drift is: a. the change in allele frequencies produced by random factors. b. the result of large populations. c. the opposite of founder effect. d. not associated with evolutionary change. e. the change in allele frequencies produced by nonrandom factors.

ANS: a REF: Factors that Produce and Redistribute Variation 37. Which of the statements below is false regarding the relationship between malaria and the HbS allele? a. There is no geographic correlation between the distribution of the HbS allele and malaria. b. Heterozygotes have greater resistance to malaria than homozygous individuals. c. The malarial parasite does not reproduce very well in the red blood cells of heterozygotes. d. Malaria is caused by the Plasmodium parasite. e. Most people are homozygous for the HbA allele.

ANS: a REF: Natural Selection Is Directional and Acts on Variation 38. The HbS allele increased in frequency in West African populations due to which of the following? a. Sickle-cell anemia b. Genetic drift c. Migration d. Increased mutation rates e. Natural selection ANS: e REF: Natural Selection Is Directional and Acts on Variation

True/False Questions 1. All human genetic disorders are inherited as recessive traits.

ANS: False REF: The Genetic Principles Discovered by Mendel 2. Recessive genotypic expressions are associated with homozygous alleles..

ANS: True REF: The Genetic Principles Discovered by Mendel 3. Dominance and recessiveness are all-or-nothing situations because the recessive allele has no phenotypic effects in heterozygotes.

ANS: False REF: The Genetic Principles Discovered by Mendel 4. Melanin production is the result of interactions between several different loci.

ANS: True

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REF: Polygenic Inheritance 5. Polygenic traits account for few, if any, of the readily observable phenotypic variation seen in humans.

ANS: False REF: Polygenic Inheritance 6. The genotype sets limits and potentials for development and interacts with the environment to produce the phenotype.

ANS: True REF: Genetic and Environmental Factors 7. Mitochondrial DNA (mtDNA) is extremely useful for studying genetic changes over time.

ANS: True REF: Mitochondrial Inheritance 8. New alleles are always the results of mutations.

ANS: True REF: Factors that Produce and Redistribute Variation 9. Genetic drift is the random factor in evolution.

ANS: True REF: Factors that Produce and Redistribute Variation 10. The relationship between malaria and the HbS allele is an example of natural selection as a factor that can cause directional change in allele frequencies.

ANS: True REF: Natural Selection Is Directional and Acts on Variation 11. A manifestation of sickle-cell anemia is the abnormal hemoglobin S reduces the ability of red blood cells to transport oxygen throughout the body.

ANS: True REF: Natural Selection Is Directional and Acts on Variation 12. In regions where malaria is present, it acts as a selective agent that favors the heterozygous phenotype, because people with sickle-cell trait produce more offspring than those with only normal hemoglobin, who may die of malaria.

ANS: True REF: Natural Selection Is Directional and Acts on Variation

Short Answer Questions 1. What is selective breeding?

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ANS: It is a practice in which animal or plant breeders choose which individuals to mate (plant) so that they can create desirable traits in the offspring.

REF: Introduction 2. Explain Mendel’s principle of independent assortment.

ANS: It is the principle which argues that the distribution of one pair of alleles into gametes does not the influence the distribution of another pair. Genes controlling different traits are assorted separately.

REF: The Genetic Principles Discovered by Mendel 3. What are the typical Mendelian phenotypic and genotypic ratios in the F2 generation for a cross of two heterozygous tall plants, where tall is a dominant trait? Why are these ratios typical?

ANS: Using a Punnett square diagram the genotypes to expect are ¼ homozygous tall, ¼ homozygous short, and ½ heterozygous. The phenotypes (given that tall is dominant) would be ¾ tall and ¼ short.

REF: The Genetic Principles Discovered by Mendel 4. What kind of research is done with mitochondrial DNA? What is particular or specific about mitochondrial DNA? (In other words, how is it different from most other types of inheritance?)

ANS: Mitochondrial DNA provides ways to study genetic change over time both within a species and between species because it is inherited from one parent only (mother) and is only subject to mutation.

REF: Mitochondrial Inheritance 5. What is meant by the “modern synthesis”?

ANS: It is a synthesis of multiple lines of evidence to integrate Mendelian genetics and natural selection within evolutionary theory.

REF: Modern Evolutionary Theory 6. Explain how two parents who do not express a particular trait in their phenotype can nevertheless produce children who express the trait. Give an example of a specific trait or disease where this could occur.

ANS: The answer is the difference between genotype (carrying the trait) and phenotype (expressing the trait). Parents can be heterozygous, leaving their children a 25 percent chance of expressing a carried trait. Examples include the ABO blood system.

REF: The Genetic Principles Discovered by Mendel 7. Define genetic drift. How are founder effect and genetic drift related?

ANS: Genetic drift is change in allele frequencies produced by random factors in small populations and founder effect is a type of genetic drift in which allele frequencies are altered in small populations take from or remnants of a larger population.

REF: Factors that Produce and Redistribute Variation 8. What is a genetic bottleneck and how is it caused?

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ANS: It refers to the loss of genetic diversity within a species caused by a decline in numbers and constrained breeding.

REF: Factors that Produce and Redistribute Variation 9. What is meant by the statement, “natural selection is the one factor that can cause directional change in allele frequency relative to specific environmental factors”?

ANS: It means that if the environment changes, then selective pressures change and allele frequencies shift in response.

REF: Natural Selection Is Directional and Acts on Variation

Essay Questions 1. Why is mutation an important element in accounting for the variation in mtDNA? What are the factors that redistribute genetic variation?

ANS: Will vary REF: Factors that Produce and Redistribute Variation 2. Using the HbS allele to illustrate, describe why fitness levels are a function of the environment.

ANS: Will vary REF: Natural Selection Is Directional and Acts on Variation 3. Discuss the differences between Mendelian and polygenic modes of inheritance. Provide an example of a Mendelian and a polygenic trait.

ANS: Will vary REF: Polygenic Inheritance 4. Allele frequencies are indicators of the genetic makeup of a population. Use the example of ABO blood types to show how allele frequencies change.

ANS: Will vary REF: Mendelian Inheritance in Humans

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CHAPTER 5: PROCESSES OF MACROEVOLUTION Chapter Outline I.

Introduction A. Macroevolution refers to large-scale evolutionary processes.

1. These processes can be understood in light of geological history, the principles of classification, and hypotheses concerning modes of evolutionary change.

II. How We Connect: Discovering the Human Place in the Organic World A. Biologists deal with the complexity of the living world by grouping or classifying organisms.

1. Classification reduces the apparent complexity and is meant to indicate evolutionary relationships.

B. Multicellular organisms that move about and ingest food are called animals.

1. Within the kingdom Animalia, there are more than 20 major groups called phyla. a. The phylum Chordata includes animals with a nerve chord, gill slits (present during development), and a supporting chord along the back. (i) Most chordates are vertebrates (vertebral column). The vertebrates are composed of five classes, one of which is mammals.

C. Taxonomy is the field that specializes in establishing the rules of classification.

1. Physical similarities are useful in taxonomy, but must be traits that are indicative of evolutionary descent.

2. Basic genetic regulatory mechanisms are highly conserved in animals; they have been maintained relatively unchanged for hundreds of millions of years. a. Homologies are structures shared by species because of descent from a common ancestor. b. Similar structures (called analogies) may arise in different lineages not because of common descent, but because they are the product of similar functional demands. (i) The process that produces analogies is called homoplasy.

III. Constructing Classifications and Interpreting Evolutionary Relationships A. The two major schools of classification are evolutionary systematics and cladistics.

B. Comparing Evolutionary Systematics with Cladistics 1. Evolutionary systematics and cladistics have some features in common. a. Both schools trace evolutionary relationships and construct classifications. b. Both schools recognize that some features (characters) are more informative of evolutionary relationships than others. c. Both schools focus exclusively on homologies.

2. These two schools differ in how characters are chosen, which groups are compared, and how the results are ultimately interpreted and incorporated into evolutionary schemes and classifications. a. Cladistics is concerned with explicitly and rigorously defining kinds of homologies that yield the most useful information. (a) Ancestral traits (those traits shared through common distant ancestry) do not provide enough information to make accurate evolutionary interpretations of relationships between different groups. (b) Cladistics focuses on lineages that share a common ancestor, or clades. (c) Derived (modified) traits are informative when identifying clades because they are modified from the ancestral condition; cladistics concentrates on these traits.

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1. Consider several traits, decide which are ancestral and which are derived, and finally try to recognize the complexity introduced by homoplasy.

2. Any modification in any species is constrained by that species’ evolutionary legacy—that is, what the species starts out with.

D. Using Cladistics to Interpret Organisms 1. In a proposed relationship between dinosaurs and birds feathers is an example of shared derived characteristics.

2. Traditional evolutionary systematics uses a phylogeny, or phylogenetic tree, to illustrate evolutionary relationships, whereas cladistics uses a cladogram. a. Phylogenetic trees differ from cladograms in two primary ways: (i) A phylogenetic tree incorporates the dimension of time. (ii) Phylogenetic trees use hypothesized ancestor-descendant relationships.

3. Ultimately, most physical anthropologists use information from cladistic analyses to produce phylogenetic trees.

IV. Definition of Species A. The most basic and fundamental level of classification is the species.

B. Though there are various definitions of species, the biological species concept is a depiction of species as groups of individuals capable of fertile interbreeding, but reproductively isolated from other such groups.

C. Processes of speciation explain how different species came about.

1. Speciation is the macroevolutionary process that produces new species. a. The biological species concept emphasizes geographic isolation during speciation. (i) The combined effects of genetic drift and natural selection followed by behavioral isolation are central to the speciation process.

D. Interpreting Species and Other Groups in the Fossil Record 1. The goal of assigning genus and species names to fossil remains is to make meaningful biological statements about the amount of variation present. a. In addition to individual variation, we also have to assess other sources of variation such as age changes and differences between individuals due to sexual dimorphism.

E. Recognition of Fossil Species 1. Since the biological species concept cannot be tested in fossil species, we have to refer to the levels of variation present in living animals. a. Intraspecific variation is caused by individual, age, and/or sex differences within the species. b. Interspecific variation is between-species variation.

2. The paleospecies concept is used for fossil species in order to account for variation both through often a long time span. a. Constructing paleospecies is an arbitrary process. b. There are two main approaches: the “splitters” and the “lumpers.” (i) “Splitters” claim that speciation occurred frequently during hominin evolution and often identify numerous fossil hominin species in a sample. (ii) “Lumpers” assume that speciation was less common and see much variation as being intraspecific.

F. Recognition of Fossil Genera 1. The genus is defined as a group of species composed of members more closely related to each other than they are to species from any other genus.

2. Grouping species into genera is also a subjective process, especially when fossils are considered. a. Possible test is check for the results of hybridization between individuals of different species (which cannot be done with animals which are now extinct).

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b. Species that are members of the same genus share the same broad adaptive zone more basic than the narrower ecological niche. c. Classification by genus is not as straightforward (for example, some include Homo troglodytes and Homo sapiens).

V. What Are Fossils and How Do They Form?

A. Fossils are traces of ancient organisms and can be formed in many ways. (Microfossils are small remains of microorganisms).

1. Mineralization is the process in which parts of animals (some plants) become transformed into stone-like structures, e.g. silica or iron seep into tiny spaces within a bone.

2. Traces of life-forms can be trapped in tree resin (amber).

3. Imprints of tracks or leaves can be left in hardened mud.

B. Whether a dead animal or plant will become fossilized depends not only on how it died but also where it died.

1. The chance of an animal or plant becoming fossilized is generally quite low.

C. Taphonomy is the study of how bones and other materials come to be buried in the earth and preserved as fossils.

VI. Vertebrate Evolutionary History: A Brief Summary A. The geological time scale divides the earth’s history into eras, periods, and epochs.

1. The first vertebrates appear in the fossil record in the early Paleozoic (500 mya).

2. Mammal-like reptiles diversified at the close of the Paleozoic (250 mya). a. These forms are probably ancestors of modern mammals.

B. Continental drift, explained by plate tectonics, had profound evolutionary effects during the Paleozoic and the Mesozoic; groups of animals were separated from each other, and mammals and reptiles were redistributed around the globe.

1. During the late Paleozoic Era, the continents came together to form Pangaea.

2. Gondwanaland, consisting of South America, Africa, Antarctica, Australia, and India, began to split off from Pangaea during the early Mesozoic. a. The other continents (North America, Greenland, Europe, and Asia) formed Laurasia.

3. The continents continued to move and began to assume their present positions by the end of the Mesozoic (ca. 65 mya).

C. The dominant form of land vertebrates during the Mesozoic Era was the dinosaur.

D. Mammalian Evolution 1. The earliest mammals also existed during the early Mesozoic Era. 2. The Cenozoic Era is known as the Age of Mammals (all living groups of mammals diverged by 75 mya). a. The diversification of the mammals followed the extinction of the dinosaurs, since new ecological niches became available. b. Mammals were successful because they evolved a complex brain and had flexible behaviors. (i) Mammals are placental, in utero development. (ii) Reptiles have homodont dentition, whereas mammals have heterodont dentition.

This allows them to process a wide variety of foods. (i) The primitive mammalian dental formula is 3.1.4.3. (ii) A disproportionate represented in the fossil record; a vast majority of remains are teeth. (iii) Mammals (and birds) maintain a constant internal body temperature; they are endothermic.

3. The Emergence of Major Mammalian Groups

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a. The three major subgroups of mammals are monotremes, marsupials, and placental mammals. (i) The monotremes are the most primitive mammals because they lay eggs. (ii) In marsupials, the young are born extremely immature and complete their development in the mother’s pouch. (iii) Placental mammals nourish the fetus with a specialized tissue, the placenta. (i) The placenta permits a longer gestation period resulting in a more completely developed central nervous system in the fetus. (ii) Placental mammals have a wider range of learning stimuli after birth during a lactation period referred to as “bond of milk.”

VII. Processes of Macroevolution A. Adaptive Radiation is the rapid expansion and diversification of new life forms into open ecological niches.

1. A species will diverge into as many variations as allowed by: a. Its adaptive potential. b. The adaptive opportunities of the ecosystem. (i) For example, the evolution of the reptilian egg caused the adaptive radiation of the reptiles by opening new adaptive niches on land.

B. Generalized and Specialized Characteristics 1. Another aspect of evolution is the transformation of generalized characteristics into specialized characteristics. a. Traits that are adapted for many functions are considered generalized. b. Generalized and specialized can also refer to the entire organism. (i) Species that are generalized have the greatest rapid adaptive potential.

C. Working Together: Microevolution and Macroevolution 1. Microevolution and macroevolution don’t need to be considered separately, as some evolutionary biologists have suggested. a. They are processes are driven by similar factors; however, macroevolution takes much longer to occur than microevolution. b. Rates of evolutionary change can speed up at certain times and slow down during other periods. c. Must crucially, natural selection is influenced by how fast genetic changes appear and spread within a species.

Key Terms and Concepts Adaptive radiation, p. 115-116 Analogies, p. 101 Ancestral, p. 102 Biological species concept, p. 105 Chordata, p. 98 Clade, p. 102 Cladistics, p. 101 Cladogram, p. 104 Classification, p. 98 Continental drift, p. 112 Derived (modified), p. 102 Ecological niche, p. 108 Endothermic, p. 115 Copyright © 2017 Cengage Learning. All Rights Reserved.

Epochs, p. 113 Evolutionary systematics, p. 101 Fossils, p. 109 Genus, p. 108 Geological time scale, p. 111 Heterodont, p. 114 Homologies, p. 101 Homoplasy, p. 101 Interspecific, p. 107 Intraspecific, p. 107 Mineralization, p. 109 Paleospecies, p. 107 Phylogenetic tree, p. 104 Placental, p. 114 Sexual dimorphism, p. 107 Shared derived, p. 104 Speciation, p. 105 Taphonomy, p. 111 Vertebrates, p. 98

Lecture Suggestions 1. Compare evolutionary systematics with cladistics and develop a list of pros and cons associated with each approach. Discuss how our scientific understanding of evolution has shifted over time.

2. Draw students into a lecture on the adaptive radiation of the mammals (including primates) by presenting current hypotheses concerning the extinction of the dinosaurs at the end of the Cretaceous.

Use up-to-date information on the University of California, Berkeley’s Museum of Paleontology website http://www.ucmp.berkeley.edu/.

3. Consider the various types of fossils that have helped construct what we know of the human lineage.

Show the Laetoli footprints and discuss how they were fossilized (see http://www.pbs.org/wgbh/evolution/library/07/1/l_071_03.html) and then compare these to the fossils of the australopithecine, Lucy (see http://www.bbc.com/earth/story/20141127-lucy-fossil-revealedour-origins).

4. Discuss the importance of geographical isolation and continental drift and then present the geological time scale and emergence of species following the break-up of Gondwanaland and Laurasia. Have students track the diversification of species during these time periods.

Internet Exercises 1. Go online to the University of California, Berkeley’s Museum of Paleontology Hall of Mammals http://www.ucmp.berkeley.edu/mammal/mammal.html to better understand the evolution and classification of mammals.

2. An excellent site on the various processes of fossilization is at http://www.fossilmuseum.net/fossilrecord/fossilization/fossilization.htm.

3. Visit http://evolution.berkeley.edu/evolibrary/article/phylogenetics_01 and try the interactive tutorial that teaches: How to read an evolutionary tree, How to classify organisms based on evolutionary

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trees, How to reconstruct an evolutionary tree, and How evolutionary trees are used.

4. For more on genetic bottlenecking and the current status of the African cheetah, see the website at http://cheetah.org/about-the-cheetah/genetic-diversity/.

Multiple Choice Questions 1. What do we call the ordering of organisms into categories, such as orders or families? a. Evolution b. Classification c. Parallelism d. Analogy e. Generalization ANS: b REF: How We Connect: Discovering the Human Place in the Organic World 2. Ideally, taxonomic classification: a. reflects evolutionary relationships. b. is based on the presence of acquired characteristics. c. is always based solely on between-species behavioral similarities. d. reflects the current geographic distribution of species. e. is only applicable to nonhuman species.

ANS: a REF: How We Connect: Discovering the Human Place in the Organic World 3. Animals with a nerve cord along the back and gill slits during some developmental stage are called: a. insects. b. invertebrates. c. chordates. d. metazoans. e. underdeveloped.

ANS: c REF: How We Connect: Discovering the Human Place in the Organic World 4. Vertebrates include all of the following except: a. birds. b. insects. c. amphibians. d. mammals. e. fishes.

ANS: b REF: How We Connect: Discovering the Human Place in the Organic World 5. Structural similarities shared by species that are acquired by descent from a common ancestor are called: a. analogies. b. homologies. c. acquired.

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d. uncommon. e. uninformative of evolutionary relationships.

ANS: b REF: How We Connect: Discovering the Human Place in the Organic World 6. What do we call structural similarities between species that are based on common function and not on common evolutionary descent? a. Acquired b. Generalized c. Non-adaptive d. Analogies e. Homologies ANS: d REF: How We Connect: Discovering the Human Place in the Organic World 7. What is the evolutionary process that produces analogous structures called? a. Speciation b. Homology c. Homoplasy d. Founder effect e. Evolutionary systematics ANS: c REF: How We Connect: Discovering the Human Place in the Organic World 8. Which two primary schools of classification are discussed in the text? a. Generalized and specialized b. Organic and inorganic c. Evolutionary systematics and cladistics d. Cladistics and non-cladistics e. Ancestral and derived (modified) ANS: c REF: Constructing Classifications and Interpreting Evolutionary Relationships 9. Structural similarities shared by a wide array of distantly-related species that are inherited from a remote ancestor, such as the number of bones in the forelimb, are termed: a. specialized. b. ancestral (primitive). c. adaptive radiations. d. analogies. e. derived (modified).

ANS: b REF: Constructing Classifications and Interpreting Evolutionary Relationships 10. What is the term for traits that reflect specific evolutionary lineages which can be informative of evolutionary relationships? a. Ancestral (primitive)

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b. c. d. e.

Acquired Derived (modified) Convergent characters Analogies

ANS: c REF: Constructing Classifications and Interpreting Evolutionary Relationships 11. When assessing evolutionary relationships, one approach is to focus on derived (modified) characteristics. What is this approach called? a. Taxonomy b. Phylogeny c. Classification d. Cladistics e. Homoplasy ANS: d REF: Constructing Classifications and Interpreting Evolutionary Relationships 12. In grouping organisms together in a cladistic classification, the most important characteristics are those that are: a. ancestral. b. derived (modified). c. primitive. d. analogous. e. classified.

ANS: b REF: Constructing Classifications and Interpreting Evolutionary Relationships 13. An hypothesis regarding ancestor-descendant relationships that includes a time scale is called a: a. cladogram. b. phylogenetic tree. c. phylogram tree. d. hypogram tree. e. cladistic tree.

ANS: b REF: Constructing Classifications and Interpreting Evolutionary Relationships 14. Unlike a cladogram, a phylogenetic tree: a. includes the dimension of time. b. does not suggest ancestral-descendant relationships. c. is one-dimensional. d. are used by physical anthropologists to identify and assess the utility of traits. e. are used by physical anthropologists to make testable hypotheses regarding relationships between groups of organisms.

ANS: a REF: Constructing Classifications and Interpreting Evolutionary Relationships

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15. Speciation can occur as a result of all of the following except: a. geographic isolation. b. natural selection acting on populations. c. ecological separation. d. lack of differences in habitats. e. limited gene exchange.

ANS: d REF: Definition of Species 16. Assigning fossil remains to a particular primate species: a. is an uncomplicated process. b. requires splitting samples into as many species as possible. c. requires making comparisons to well-known living species of primates. d. can be accomplished only if the species is sexually dimorphic. e. requires making comparisons only with modified and derived primates.

ANS: c REF: Definition of Species 17. Morphological variation between individuals within a species: a. may be the product of male/female morphological differences. b. is called interspecific variation. c. indicates phylogenetic parallelism. d. is unimportant when interpreting the fossil record. e. produces large numbers of identical individuals.

ANS: a REF: Definition of Species 18. A genus may be defined as a group of: a. individuals who interbreed but who are reproductively isolated from other such groups. b. closely related species. c. one or more species that do not differ from each other in basic ways. d. members of the same species. e. individuals more closely related to individuals of another species in another genus.

ANS: b REF: Definition of Species 19. Grouping contemporaneous species into genera: a. is never a subjective process. b. can be facilitated by identifying species that interbreed and produce live hybrid offspring. c. is always easy and accurate, although there is an acute lack of fossil evidence. d. is problematic and therefore not a common practice of physical anthropologists. e. requires similarities between species in one genus and species of another genus.

ANS: b REF: Definition of Species 20. Continental drift:

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a. b. c. d. e.

had no real impact on the evolutionary history of vertebrates. never actually occurred. is the movement of the continents on the Earth’s surface. ceased to occur several million years ago and has no effect on species development. occurred only in the Old World.

ANS: c REF: Vertebrate Evolutionary History 21. As discussed in the text, long-term continental drift had significant evolutionary ramifications because: a. groups of animals were no longer isolated from each other by oceans. b. the distribution of mammals and other land vertebrates were unaffected. c. geological activities induced volcanic activities which decimated populations of placental mammals. d. groups of animals were isolated from each other by oceans. e. scientists can map the changes that occurred and see evolution as it happened.

ANS: d REF: Vertebrate Evolutionary History 22. Which of the following is least likely to become a fossil? a. Mammalian teeth b. Marine shell c. Cranial bones d. Spinal vertebrae e. Reptilian internal body organ ANS: e REF: What Are Fossils and How Do They Form?

23. The study of how bones and other material come to be preserved as fossils is called: a. taphonomy. b. cladistics. c. paleoanalysis. d. fossilization. e. forensics.

ANS: a REF: What Are Fossils and How Do They Form?

24. Development of a mammalian brain requires all except: a. Longer period of growth. b. More intense period of growth. c. Slower development in utero and after birth. d. Social system that ensure ample learning. e. The lack of a “bond of milk” between mother and infant.

ANS: e REF: Vertebrate Evolutionary History

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25. The diversification of the mammals occurred mostly during the: a. Pleistocene. b. Mesozoic. c. Quaternary. d. Cenozoic. e. Paleozoic.

ANS: d REF: Vertebrate Evolutionary History 26. Mammals, in contrast to reptiles: a. have larger brains. b. are homodont. c. cannot process a wide variety of foods. d. lack fur. e. are ectothermic.

ANS: a REF: Vertebrate Evolutionary History 27. What does the term endothermic refer to? a. Mammalian tooth shapes b. The loss of heat in animals without fur c. Using metabolic activity to maintain a constant internal body temperature d. Staying warm by laying in the sun e. Energy is generated externally ANS: c REF: Vertebrate Evolutionary History 28. Endothermic animals include mammals and which of the following? a. Fish b. Amphibians c. Birds d. All dinosaurs e. Reptiles ANS: c REF: Vertebrate Evolutionary History 29. What are monotremes? a. Marsupials b. Viviparous reptiles c. Egg-laying fish d. Placental mammals e. Egg-laying mammals ANS: e REF: Vertebrate Evolutionary History 30. What type of ancestor provides the flexible evolutionary basis for rapid diversification?

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a. b. c. d. e.

Those with sexually dimorphic characteristics Those associated with monotremes Those with generalized characteristics Those with specialized characteristics Those with derived and adaptive characteristics

ANS: c REF: Processes of Macroevolution 31. What is the term for the rapid expansion and diversification of groups of organisms into newly available ecological niches? a. Generalization b. Homology c. Parallel evolution d. Adaptive radiation e. Specialization ANS: d REF: Processes of Macroevolution 32. The diversification of reptiles facilitated by the evolution of the reptilian egg is a good example of which of the following? a. Parallel evolution b. Specialization c. Homology d. Adaptive radiation e. Devolution ANS: d REF: Processes of Macroevolution 33. The theory that macroevolution proceeds as the result of gradual microevolutionary change: a. is the only explanation of speciation accepted by biologists today. b. is called the theory of punctuated equilibrium. c. has been refuted. d. has been questioned as the exclusive mode of speciation. e. postulates rapid evolutionary change followed by long periods of stasis.

ANS: d REF: Processes of Macroevolution

True/False Questions 1. The phylum Chordata includes all animals with a nerve cord, gill slits, and supporting cord along the back.

ANS: True REF: How We Connect : Discovering the Human Place in the Organic World 2. Vertebrates are divided into five phyla.

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ANS: False REF: How We Connect : Discovering the Human Place in the Organic World 3. Cladistics is an approach to classification that makes evolutionary interpretations based solely on shared ancestral characters.

ANS: False REF: Constructing Classifications and Interpreting Evolutionary Relationships 4. Cladistic analysis usually does not provide enough data to discern ancestor-descendant relationships.

ANS: True REF: Constructing Classifications and Interpreting Evolutionary Relationships 5. Sexual dimorphism refers to reproductive differences among mammal species.

ANS: False REF: Definition of Species 6. Taphonomy is the study of human artifacts.

ANS: False REF: What Are Fossils and How Do They Form ?

7. The variation that exists among individuals within a species is termed interspecific variation.

ANS: False REF: Definition of Species 8. Adaptive radiation is a process of macroevolution.

ANS: True REF: Processes of Macroevolution 9. During the Paleozoic era, reptiles were the dominant land vertebrates.

ANS: False REF: Vertebrate Evolutionary History 10. The mammals achieved rapid evolutionary success because they possessed several characteristics related to learning and general behavioral flexibility.

ANS: True REF: Vertebrate Evolutionary History 11. The Cenozoic contains seven epochs.

ANS: True REF: Vertebrate Evolutionary History 12. Much of what we know about the history of life comes from studying fossils.

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ANS: True REF: Vertebrate Evolutionary History

Short Answer Questions 1. Define analogous and homologous traits and provide an example of each.

ANS: Homologies are structures that are shared by species on the basis of descent from a common ancestor (Hox genes) and analogies are similarities between organisms based strictly on common function, with no assumed evolutionary descent (wings on butterflies and birds).

REF: How We Connect: Discovering the Human Place in the Organic World 2. Contrast ancestral traits with derived traits.

ANS: Ancestral traits are characters inherited by a group of organisms from a remote ancestor and not diagnostic of groups (lineages) that diverged after the character first appeared. Derived traits refer to those characters that are modified from the ancestral condition and thus diagnostic of particular evolutionary linages.

REF: Constructing Classifications and Interpreting Evolutionary Relationships 3. What is a heterodont?

ANS: It is an ancestral mammalian trait of having different kinds of teeth.

REF: Vertebrate Evolutionary History 4. What are the influences of long-term continental drift on the evolution of terrestrial life forms?

ANS: Continental drift creates possibility of geographical isolation, a factor necessary for the development of new species (speciation).

REF: Vertebrate Evolutionary History 5. Fossils form in various ways. Name two of the most common ways that fossils form.

ANS: The most common are through mineralization or through preservation in tree resin and/or hardened mud.

REF: What Are Fossils and How Do They Form?

6. Define the term “adaptive radiation” and explain why it is important to the principle of evolution.

ANS: It is the relatively rapid expansion and diversification of life-forms into new ecological niches.

New environments are the source of new selective pressures.

REF: Processes of Macroevolution 7. What does it mean to say that evolutionary processes can be both microevolution and macroevolution?

ANS: They are both driven by similar factors; their difference is by scale and over time.

REF: Processes of Macroevolution

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Essay Questions 1. Contrast the two schools of taxonomy: evolutionary systematics and cladistics.

ANS: Will vary REF: Constructing Classifications and Interpreting Evolutionary Relationships 2. Define “species” and the biological species concept. Why is the latter the one preferred by most biologists?

ANS: Will vary REF: Definition of Species 3. When scientists assign fossil remains to genera and species, they must first assess the variation present in the fossil sample to determine its biological significance. What are the sources of morphological variation in fossil samples?

ANS: Will vary REF: What Are Fossils and How Do They Form?

4. Explain the difference between generalized and specialized characteristics. What are examples of each in terms of the adaptive potential?

ANS: Will vary REF: Processes of Macroevolution 5. Give an overview of the modes of evolutionary change, including both microevolution and macroevolution. Why does the textbook argue that the major differences between the two seem to be one of scale?

ANS: Will vary REF: Processes of Macroevolution

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CHAPTER 6: AN OVERVIEW OF THE PRIMATES Chapter Outline I.

Introduction A. One way to understand our species is to compare its anatomy and behavior with our closest living relatives.

B. The comparative approach helps explain how and why physiological and behavioral systems evolved as adaptive responses to various selective pressures.

C. This chapter describes the physical characteristics that define the Order Primates, gives an overview of the major groups of living primates, and introduces methodology used to compare living primates genetically.

1. Evolution is not a goal-directed process; the fact that lemurs evolved before the anthropoids does not mean that lemurs “progressed” to become anthropoids.

2. Each primate group evolved unique morphologies as they adapted to their environments, so no one group should be thought of as the apex of evolution.

II. Primate Characteristics A. Primates share traits with other mammals, including: body hair, a long gestation period and live births, mammary glands, different types of teeth (heterodonty), constant internal body temperature maintained through physiological means (endothermy), increased brain size, and the capacity for learning and behavioral flexibility.

1. Primates are generalized, having retained many primitive (or ancestral) mammalian traits.

B. There are a few traits that reflect a common evolutionary history as highly social, arboreal beings.

C. Limbs and Locomotion 1. A tendency toward erect posture.

2. A generalized limb structure.

3. Prehensile hands (and sometimes feet): a. Retention of five digits on hands and feet. b. An opposable thumb and in most, a divergent and partially opposable big toe. c. Nails instead of claws. d. Tactile pads enriched with sensory nerve fibers at the end of digits.

D. Dentition and Diet 1. Lack of dietary specialization; in general, primates are omnivorous.

2. A generalized dentition. a. The senses and the brain: diurnal primates rely heavily on vision, less on smell. i.

Color vision (in diurnal species); nocturnal primates don’t have color vision. ii.

Depth perception, stereoscopic vision: (a) Eyes positioned toward the front of the face; overlapping visual fields provide binocular vision. (b) Visual information from each eye transmitted to visual centers in both hemispheres of the brain. (c) Visual information organized into three-dimensional images by specialized structures in the brain. iii.

Decreased reliance on the sense of smell, olfaction. iv.

Expansion and increased complexity of the brain, most evident in visual and association areas of neocortex where information from different sensory modalities is combined.

E. Maturation, Learning, and Behavior

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1. A more efficient means of fetal nourishment, longer periods of gestation, reduced numbers of offspring, delayed maturation, and longer life span.

2. A greater dependence on flexible, learned behaviors.

3. The tendency to live in social groups and the permanent association of adult males with the group.

4. The tendency toward diurnal activity patterns.

III. Primate Adaptations A. Evolutionary Factors 1. The primate adaptive niche is in the trees, so traditionally, primate characteristics have been explained as the result of adaptation to arboreal living and adaptive niche in the trees, called the arboreal hypothesis.

2. An alternative is the visual predation hypothesis, which argues that primates adapted to hunting the lowest tiers of the forest canopy and captured prey items; forward-facing eyes, grasping digits and nails, not claws, were adaptations.

3. Another scenario proposes that primates developed in conjunction with the rise of the flowering plants about 140 mya as a response to demand for fine visual and tactile discrimination to feed on small food items.

4. These hypotheses are not mutually exclusive.

B. Geographical Distribution and Habitats 1. Primates are found primarily in tropical or semitropical habitats of the New and Old Worlds. a. Most primates are arboreal, although a few (including some Old World monkeys, chimpanzees, and gorillas) spend much of the day on the ground.

C. Diet and Teeth 1. Primates are generally omnivorous.

2. Almost all primates have four kinds of teeth: incisors, canines, premolars, and molars. a. The dental formula describes the number of each tooth type in each quadrant of the mouth. (i) In primates and other mammal groups, there has been a general trend over time towards the reduction in the number of teeth. (ii) Old World anthropoids (humans, apes, monkeys) have a dental formula of 2.1.2.3. (iii) Most New World monkeys have a dental formula of 2.1.3.3. b. Most primate molars and premolars have low, rounded cusps reflecting an overall lack of dietary specialization.

D. Locomotion 1. Even though most primates are quadrupedal to some degree, many primates employ more than one form of locomotion. b. Vertical clinging and leaping is a form of locomotion common in some lemurs and tarsiers. c. Brachiation (arm swinging) is a form of suspensory locomotion in which the body is alternately supported under either forelimb. (i) Apes and humans are capable of true brachiation. (ii) Some New World monkeys are termed semibrachiators, since they use a combination of leaping along with arm swinging. (iii) In some New World monkeys, suspensory behaviors are enhanced by the use of a prehensile tail. (iv) Habitual brachiators have arms that are longer than their legs, a short lower spine, long curved fingers, and shortened thumbs. d. All apes have arms that are longer than legs, and some practice a form of quadrupedalism called knuckle walking.

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IV. Primate Classification A. Primates are categorized into two suborders: Strepsirhini (lemurs and lorises) and Haplorhini (tarsiers, monkeys, apes and humans).

B. Traditional taxonomies were based on physical similarities between species and lineages.

1. Using physical similarities alone can present problems, since similar morphologies may arise in separate lineages. b. Comparative genomics provides a more accurate picture of evolutionary and biological relationships between species. a. Chimpanzee and human DNA base sequences are about 98.4 to 99.4 percent identical, indicating that humans and chimpanzees are more similar to each other than either is to the gorilla. When the entire genome is considered, the genetic difference between chimpanzees and humans is between 2.7 and 6.4% b. The fact that humans have much more non-protein coding DNA than do the other primates studied may contribute to why we differ from our close relatives.

V. A Survey of the Living Primates A. Lemurs and Lorises exhibit more ancestral mammalian characteristics than any other primate group.

1. Distinguished by greater reliance on olfaction and presence of long snout and moist fleshy pad, or rhinarium; more laterally placed eyes; differences in reproductive physiology; shorter gestation and maturation periods; a “dental comb.”

2. Lemurs are found only on the island of Madagascar and adjacent islands off the east coast of Africa. a. They are highly endangered today; some 91% of the species threatened with extinction. b. Lemurs eat a variety of foods: (i) Larger lemurs are diurnal and eat a variety of foods (leaves, fruit, bark, and shoots). (ii) Smaller lemurs are nocturnal and insectivorous. c. Several species live in large social units, while others live in monogamous family units or are solitary.

3. Lorises are found in the tropical forests and woodlands of India, Sri Lanka, Southeast Asia, and Africa, able to survive by becoming nocturnal. Included in this category are galagos (also known as bush babies). (i) Some are almost entirely insectivorous, while others eat fruit, and leaves. (ii) Many use a climbing form of quadrupedalism and have a slow movement, while other are vertical climbers and leapers. (iii) Lorises and galagos frequently forage alone; females often leave their young to forage (called parking), a behavior not seen in most primate species.

Tarsiers are only found on the islands of Southeast Asia. (i) They are nocturnal and insectivorous, and their social unit consists of a mated pair and their offspring.

B. Tarsiers are found only on certain islands in Southeast Asia, but they inhabit a wide range of habitats.

1. They are nocturnal insectivores who leap from lower branches and shrubs onto prey.

2. The basic social unit is a mated pair and their young offspring.

3. They are highly specialized (derived) animals: a. Their large, immobile eyes dominant their face. b. They can rotate their heads 180 degrees.

C. Anthropoids: Monkeys, Apes, and Humans 1. Although there is much variation among anthropoids, they share certain features that distinguish them from lemurs and lorises: a. Larger average body size.

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b. Larger brain in absolute terms and relative to body weight. c. Reduced reliance on sense of smell; absence of rhinarium. d. Increased reliance on vision, with forward-facing eyes more to the front of the face. e. Greater degree of color vision. f. Back of eye socket protected by a bony plate. g. Different type of blood supply to the brain. h. Fusion of the two sides of the mandible. i. More generalized dentition. (absence of a dental comb). j. Difference in female internal reproductive anatomy. k. Longer gestation and maturation periods. l. Increased parental care. m. More mutual grooming.

2. Approximately 85 percent of all primates are monkeys, divided into 195 species. a. New World Monkeys range into approximately 70 monkey species in a wide range of arboreal environments throughout most forested areas in southern Mexico, Central and South America. (i) They exhibit a wide range of size, diet, and ecological adaptations. (ii) Marmosets and tamarins retain claws and usually give birth to twins in a mated pair (or a female with two adult males); the males are intensively involved in infant care. (iii) Other New World species range in size widely. a. Diet varies, but most eat a combination of fruits and leaves as well as various insects. b. Locomotion is mainly quadrupedalism, but some are also semibrachiators, and some also have prehensile tails (howlers, muriquis, and spider monkeys). b. Old World Monkeys are the most widely distributed of the living non-human primates (except for humans). (i) They are all in a single family of Cercopithecidae, divided into two subfamilies: Cercopithecinae (the cercopithecines), and Colobinae (the colobines). (ii) Most are arboreal, but some spend a great deal of time on the ground and have hardened skin on buttocks called ischial callosities. (iii) The cercopithecines are more generalized than the colobines: a. They are omnivorous and eat almost anything. b. The majority of the species (except for macaques) are found in Africa. (iii) The colobines have narrower food preferences and mainly eat leaves, earning them the name of “leaf-eating monkeys.” a. They are found mainly in Asia (except red colobus and black-and-white colobus). (iv) Many Old World species have specific reproductive characteristics: a. They are sexually dimorphic in body size. b. Females have pronounced cyclical changes of external genitalia associated with estrus. c. Monogamous pairs are uncommon among Old World monkeys; colobines live in small groups; baboons and most macaques live in large social groups.

D. Hominoids: Apes and Humans a. The super family Hominoidea includes the hominoids (apes and humans). (i) Apes are found in Asia and Africa. a. Gibbons and siamangs are the smallest of the apes. (ii) Apes and humans share the following characteristics that distinguish them from monkeys: a. Generally larger body size. b. No tail.

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c. Shorter and more stable back. d. Arms longer than legs (in apes only). e. Anatomical differences in the shoulder joint to facilitate suspensory feeding and locomotion. f. Generally more complex behavior. g. More complex brain and enhanced cognitive abilities. h. increased period of infant dependency and development. (iii) Gibbons and siamangs have distinctive anatomical features: a. Many of their body features reflect an adaptation to brachiation. b. Their basic social unit is an adult male and female, plus their offspring. c. They are highly territorial. (iv) Orangutans (Pongo pygmaeus) are found only on Indonesian islands of Borneo and Sumatra. Due to poaching and habitat loss, they are severely threatened by extinction in the wild. a. They are slow cautious climbers and almost completely arboreal. b. They have pronounced sexual dimorphism in body size. c. They are primarily frugivorous and lead solitary lives. (iv) Gorillas (Gorilla gorilla) are the largest of all the living primates. a. They live in western and eastern equatorial Africa. b. Gorillas, like orangutans, have marked sexual dimorphism in body size. c. Adult males are primarily terrestrial because of their great weight (up to 400 pounds). d. They practice a form of quadrupedalism called knuckle-walking. e. There are various types of gorillas based on geographical adaptations: western lowland gorillas, eastern lowland gorillas, and mountain gorillas. (i) Mountain gorillas leave their natal group and live in groups with one or two adult silverback males, plus several females and their subadult offspring. f. All gorillas are almost exclusively vegetarian. g. Unlike the stereotypes, gorillas are shy and gentle (except when threatened). (v) Chimpanzees are probably the best known of the nonhuman primates.

1. Chimpanzees live in equatorial Africa, but their present distribution is patchy.

2. They have smaller body sizes and less pronounced sexual dimorphism than orangutans and gorillas.

3. They are morphologically similar to gorillas. Both gorillas and chimpanzees are knuckle walkers, although chimpanzees can walk bipedally and brachiate for short distances.

4. They have a more varied diet than gorillas, including fruit, leaves, insects, and small mammals (which they hunt).

5. Chimpanzees live in large fluid communities and have complex social interactions, including some lifelong attachments.

6. They live well into their 40s and occasionally longer. (vi) Bonobos (Pan paniscus) are found only in an area south of the Zaire River.

1. Bonobos and chimpanzees are morphologically similar, but bonobos have a more linear body build. a. They are less stocky and are smaller. b. Their legs are longer relative to their arms. c. Their heads are smaller. d. They have a dark face from birth.

2. Bonobos live in fluid communities, but bonobo society is centered on malefemale bonds (rather than the close male-male bonds observed in chimpanzees).

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3. Unlike all other nonhuman primates, bonobos copulate throughout the female’s estrous cycle. They also have sexual activity among members of the same sex. (vii)Humans are the only living representatives of the habitually bipedal primates (hominins).

1. Humans are generally omnivorous and have generalized digestive systems.

2. Humans are unique among primates in that they possess a very large, neuronal complex brain and intelligence that (along with specialized anatomical structures) predispose them to use spoken language.

3. Humans are completely dependent on culture.

4. Humans possess many adaptations of the pelvis, leg, and foot that enable habitual bipedalism.

VI. Endangered Primates A. Some 70 percent of all nonhuman primate species are in danger of extinction.

B. Three reasons for worldwide depletion are: 1. Habitat destruction.

2. Human hunting.

3. Live capture for export or trade.

C. Underlying all the above reasons is unprecedented human population growth.

D. Many primate species now number only in the hundreds to the thousands of individuals and habitat loss is one of the most pressing problems; hunting pressures also exist in both Africa and South America.

E. The Bushmeat Trade 1. In the 1990s primatologists became aware of the bush meat crisis.

2. The society for conservation biology estimates over 6,000 kg of bush meat is taken monthly to just seven western cities. About 1 percent of the total is international trade.

3. Logging has been a major factor in the development of bush meat trade via construction of logging roads granting people more access to these apes.

4. Hunting non-human primates has been a common practice in South America for many years.

F. In 2007, the Democratic Republic of Congo government and the Bonobo Conservation Initiative created a bonobo reserve in the DRC encompassing some 10 percent of the total land in that country. This was a huge step forward.

Key Terms and Concepts Adaptive niche, p. 126 Anthropoids, p. 122 Arboreal, p. 126 Binocular vision, p. 124 Brachiation, p. 130-131 Cercopithecidae, p. 140 Cercopithecinae, p. 140 Cercopithecines, p. 140 Colobinae, p. 140 Colobines, p. 140 Cusps, p. 130 Dental formula, p. 130 Diurnal, p. 124 Estrus, p. 142 Frugivorous, p. 144 Copyright © 2017 Cengage Learning. All Rights Reserved.

Haplorhini, p. 132 Hemispheres, p. 124 Hominoidea, p. 142 Hominoids, p. 142 Intelligence, p. 149 Ischial callosities, p. 140 Natal group, p. 146 Neocortex, p. 124-125 Nocturnal, p. 124 Olfaction, p. 124-125 Omnivorous, p. 124 Primates, p. 122 Quadrupedal, p. 130-131 Rhinarium, p. 134 Sensory modalities, p. 124-125 Sexual dimorphism, p. 142 Stereoscopic vision, p. 124 Strepsirhini, p. 132 Territorial, p. 144 Lecture Suggestions 1. Obtain a good primate collection and distinguish a monkey from an ape. Have students pay particular attention to locomotor patterns, noting their anatomical correlates; observe the mother/infant interactions and note the similarities between these patterns and interactions of human mothers and infants.

2. Serious threats to the survival of most free-ranging nonhuman primate populations are a critical discussion topic. Certainly within our lifetimes, several primate species will become extinct in the wild. Divide students into a debate format arguing for and against protection of nonhuman primates.

What are the costs and benefits of protection?

3. Discuss the hypothesis that HIV was transmitted to humans through the eating of bonobo bush meat.

Bonobos carry the SIV virus, but do not become ill; therefore, they could be useful in solving the AIDS crisis.

4. Discuss the current state of legislation in the U.S. (H.R.1513/S.810, The Great Ape Protection and Cost Savings Act - GAPCSA) to prevent invasive research on great apes. What moral responsibility, if any, do we have to our closest relatives?

Internet Exercises 1. Go online to The Jane Goodall Institute http://www.janegoodall.org and follow the link to “What We Do” – “Protecting Great Apes.” Click the link to read about efforts to save these animals.

2. Dr. Sue Savage-Rumbaugh has worked extensively with bonobo language. Follow some of this work on the links: http://www.smithsonianmag.com/science-nature/speaking-bonobo-134931541/?no-ist and also at https://www.youtube.com/watch?v=jKauXrp9dl4.

3. There is a growing movement worldwide to protect great apes. Called the GAP Project, it seeks to extend the idea of human rights to our closest relatives. Read more about this at: http://www.projetogap.org.br/en/noticia/universal-declaration-rights-great-apes/.

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Multiple Choice Questions 1. Currently, there are approximately _______ species of non-human primates. a. 230 b. 276 c. 75 d. 186 e. 29 ANS: a REF: Introduction 2. As an Order, primates: a. have highly specialized traits. b. can be easily defined by one or two traits. c. lack traits that define the mammals. d. have generalized traits. e. have very narrow, or specialized, dietary preferences.

ANS: d REF: Primate Characteristics 3. Which one of the traits listed below is not used to define the order Primates? a. A tendency towards erect posture b. An inflexible, specialized limb structure c. Hands and feet with a high degree of prehensility d. Retention of five digits on the hands and feet e. Generalized dentition ANS: b REF: Primate Characteristics 4. Prehensile ability to grasp with five digits is: a. a variable trait in the order. b. characteristic only of monkeys. c. characteristic only of apes and humans. d. the only truly distinctive primate trait. e. hindered by an opposable thumb.

ANS: a REF: Primate Characteristics 5. The primate emphasis on the visual sense is reflected in all of the following except: a. the reduction in the size of structures related to the sense of smell. b. the presence of color vision in most species. c. a more forward-facing position of the eyes relative to most other mammals. d. visual information from each eye transmitted to visual centers in both hemispheres. e. enlarged rhinarium.

ANS: e REF: Primate Characteristics

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6. Regarding aspects of primate maturation, learning, and behavior, primates have all of the following except: a. a more efficient means of fetal nourishment. b. longer periods of gestation. c. reduced numbers of offspring. d. delayed maturation. e. decreased life span.

ANS: e REF: Primate Characteristics 7. Traditionally, primate characteristics have been explained as the result of adaptation to ________ environments. a. terrestrial b. rocky c. arboreal d. desert e. ocean ANS: c REF: Primate Adaptations 8. Adaptive niche refers to: a. an adaptive advantage in a purely terrestrial environment. b. mammalian characteristics which evolved from an arboreal environment. c. an organism’s entire way of life. d. a numerical device that indicates the number of each type of tooth. e. adaptive benefit of surrounding forests and rivers.

ANS: c REF: Primate Adaptations 9. Using all four limbs to support the body during locomotion is called: a. bipedalism. b. quadrupedalism. c. vertical clinging and leaping. d. brachiation. e. semi-brachiation.

ANS: b REF: Primate Adaptations 10. Vertical clinging and leaping is a locomotor pattern frequently practiced by which of the following? a. Apes b. Lemurs and tarsiers c. Terrestrial monkeys d. Old World monkeys e. Gibbons ANS: b

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REF: Primate Adaptations 11. Arms that are longer than the legs, and a short stable lumbar spine are traits associated with: a. brachiation. b. vertical clinging and leaping. c. arboreal quadrupedalism. d. terrestrial quadrupedalism. e. full-time bipedalism.

ANS: a REF: Primate Adaptations 12. _________ is seen in some New World monkeys, but not in any Old World monkeys. a. A grasping hand b. Quadrupedalism c. An arboreal lifestyle d. Color vision e. A prehensile tail ANS: e REF: Primate Adaptations 13. The Order Primates is traditionally divided into two suborders: a. Platyrrhine and Catarrhine. b. Strepsirhini and Haplorhini. c. Pongidae and Hominidae. d. Cercopithecoidea and Hominoidea. e. Pongo and Homo.

ANS: b REF: Primate Classification 14. The suborder Strepsirhini includes: a. lemurs and lorises. b. tarsiers, lemurs and lorises. c. lorises, chimpanzees, and gorillas. d. chimpanzees, gorillas, and humans. e. Strepsirhini is not a suborder of primates.

ANS: a REF: Primate Classification 15. Traditionally, Old World monkeys are separated from apes and humans at the level of the: a. infraorder. b. genus. c. superfamily. d. family. e. suborder.

ANS: c REF: Primate Classification

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16. DNA hybridization of humans and chimpanzees indicate they share about _________ of their DNA base sequences. a. 10 percent b. 95 percent c. 28 percent d. 99 percent e. 100 percent ANS: d REF: Primate Classification 17. The following are characteristics of tarsiers except that they: a. are restricted to the islands of Southeast Asia. b. are mainly diurnal. c. leap from branch to branch to catch insect prey. d. form stable bonds. e. inhabit a wide range of habitats.

ANS: b REF: A Survey of Living Primates 18. Tarsiers, monkeys, apes, and humans are placed together in which suborder? a. Prosimii b. Lorisoidea c. Hominoidea d. Haplorhini e. Strepsirhini ANS: d REF: Primate Classification 19. What are the most non-derived or primitive primates? a. Old World monkeys b. New World monkeys c. Tarsiers d. Lemurs and lorises e. Great apes ANS: d REF: A Survey of Living Primates 20. What are the two major groups of Strepsirhini? a. Lemurs and tarsiers b. Marmosets and howler monkeys c. Lemurs and lorises d. Baboons and macaques e. Tarsiers and lorises ANS: c REF: Primate Classification

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21. Which kind of analysis provides a more accurate picture of evolutionary and biological relationships among the primates? a. Organelle DNA b. Comparative genomics c. Comparative anatomy d. Visual predation theory e. K-selected analysis ANS: b REF: Primate Classification 22. Compared to Strepsirhini, anthropoids generally: a. have smaller body sizes. b. have decreased infant maturation periods. c. have smaller brains. d. depend less on olfaction and more on vision. e. groom less often.

ANS: d REF: A Survey of Living Primates 23. Monkeys are divided into which two major groups? a. Terrestrial and arboreal forms b. New and Old World species c. Large and small-bodied species d. Quadrupedal and bipedal e. Omnivores and frugivores ANS: b REF: Primate Classification 24. What are the smallest New World anthropoids? a. Marmosets and tamarins b. Howler monkeys and baboons c. Spider monkeys and capuchin monkeys d. Squirrel monkeys and bonobos e. Macaques ANS: a REF: A Survey of Living Primates 25. Where are Old World monkeys found? a. Africa and northern Europe b. Mexico and South America c. Sub Saharan Africa, southern Asia, and northern Japan d. India and southern Asia only e. North America and Mexico ANS: c REF: A Survey of Living Primates

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26. All Old World monkeys belong to which superfamily? a. Ominidae b. Cercopithecidae c. Callitrichidae d. Pongidae e. Monquidae ANS: b REF: A Survey of Living Primates 27. Which of the following does not characterize Cercopithecines? a. Are one subfamily of Old World monkeys b. Are more generalized than colobines c. Include baboons, guenons, and macaques d. Have cheek pouches for storing food e. Found only in Sri Lanka and Madagascar ANS: e REF: A Survey of Living Primates 28. Which of the following are not hominoids? a. Bonobos b. Gorillas c. Orangutans d. Chimpanzees e. Baboons ANS: e REF: A Survey of Living Primates 29. Sexual dimorphism: a. refers to differences between adults and adolescents with regard to sexual behavior. b. is particularly pronounced in all primate species. c. refers to differences between the sexes with regard to features such as body size. d. is more common in arboreal species. e. has not been observed in any monkey species.

ANS: c REF: A Survey of Living Primates 30. In nonhuman primates, the hormonally-initiated period of sexual receptivity is called: a. sexual dimorphism. b. sexual reciprocity. c. adaptive radiation. d. estrus. e. rhinarium.

ANS: d REF: A Survey of Living Primates

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31. Which of the following are not apes? a. Gorillas b. Orangutans c. Bonobos d. Chimpanzees e. Macaques ANS: e REF: A Survey of Living Primates 32. Compared to monkeys, hominoids: a. generally have larger body sizes and lack a tail. b. have a more elongated lower back. c. have arms and legs of equal length. d. exhibit less complex behavior. e. have a shorter period of infant dependency.

ANS: a REF: A Survey of Living Primates 33. Among the apes, the ________ have the smallest average body sizes. a. gibbons and siamangs b. bonobos c. chimpanzees d. macaques e. marmosets ANS: a REF: A Survey of Living Primates 34. Gibbons and siamangs are adapted for: a. quadrupedalism. b. bipedalism. c. brachiation. d. vertical clinging and leaping. e. knuckle-walking.

ANS: c REF: A Survey of Living Primates 35. Orangutans belong to which genus? a. Pan b. Pongo c. Gorilla d. Papio e. Hylobates ANS: b REF: A Survey of Living Primates 36. ________ have very large, highly sexually dimorphic body sizes and live largely solitary lives.

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a. b. c. d. e.

Gorillas Chimpanzees Gibbons Orangutans Humans

ANS: d REF: A Survey of Living Primates 37. Which are the largest of the living primates? a. Orangutans b. Chimpanzees c. Gibbons d. Bonobos e. Gorillas ANS: e REF: A Survey of Living Primates 38. Mountain gorilla social groups are usually composed of: a. one adult silverback male and one adult female, plus their immature offspring. b. solitary individuals, except for females with dependent young. c. one or two adult silverback males, a few adult females and their immature offspring. d. several adults of both sexes and offspring of all ages. e. several adult males plus only one female and her offspring.

ANS: c REF: A Survey of Living Primates 39. Chimpanzees live in groups composed of: a. one adult male, several females, and their young. b. large communities of bonded males and females, plus young of all ages. c. one adult male plus one adult female and their young. d. several adult females, one adult male, and any dependent young. e. multiple other primate species.

ANS: b REF: A Survey of Living Primates 40. Bonobos are: a. the most thoroughly studied primate species. b. in the same genus as the gorilla. c. behaviorally indistinguishable from chimpanzees. d. in the same genus as the chimpanzee. e. almost exclusively arboreal.

ANS: d REF: A Survey of Living Primates 41. What is a major underlying factor for the declining numbers of nonhuman primates? a. The killing of primates for human consumption

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b. c. d. e.

The trapping of live primates for biomedical research Unprecedented human population growth The trapping of live primates for the pet trade The overpopulation of nonhuman primate groups

ANS: c REF: Endangered Primates

True/False Questions 1. The fact that Strepsirhinis evolved before the anthropoids indicates that anthropoids are more evolved.

ANS: False REF: Introduction 2. Primates are found primarily in tropical and semitropical habitats of the Old World and North America.

ANS: False REF: Primate Adaptations 3. The dental formula for an Old World anthropoid is 2.1.2.3.

ANS: True REF: Primate Adaptations 4. Humans and New World monkeys both have a 2.1.2.3 dental formula.

ANS: False REF: Primate Adaptations 5. The “dental comb” is a specialization found in most of the anthropoid species.

ANS: False REF: A Survey of Living Primates 6. In the classification of the primates, the lemurs, lorises, and tarsiers would be placed in the suborder Strepsirhini.

ANS: False REF: Primate Classification 7. Colobine monkeys specialize in eating mature leaves, and are referred to as “leaf-eating monkeys.”

ANS: True REF: A Survey of Living Primates 8. Orangutan adults have a very active locomotion pattern and they frequently brachiate.

ANS: False

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REF: A Survey of Living Primates 9. In major cities throughout Europe and the U.S., illegal bushmeat is readily available.

ANS: True REF: Endangered Primates 10. Bonobo communities, like those of chimpanzees, are centered around male-male bonds.

ANS: False REF: A Survey of Living Primates 11. Humans are the only living representatives of the habitually bipedal primates (hominin tribe).

ANS: True REF: A Survey of Living Primates 12. Miss Waldron’s red colobus has officially been declared extinct.

ANS: True REF: Endangered Primates 13. Virunga National Park is a United Nations World Heritage site.

ANS: True REF: Endangered Primates

Short Answer Questions 1. List five traits used to define the order Primates.

ANS: There are many choices that may include tendency toward erect posture, generalized limb structure, prehensile hands, lack of dietary specialization, generalized dentition, color vision, depth perception, decreased reliance on smell, brain expansion, more efficient and longer fetal period, greater dependence on flexible learned behavior, tendency to live in social groups, tendency toward diurnal activities.

REF: Primate Characteristics 2. What primate traits are likely to be adaptations to arboreal lifestyles?

ANS: These primarily include increased reliance on vision, grasping hands and feet, color vision and depth perception.

REF: Primate Adaptations 3. Define three major forms of primate locomotion. Name at least one species associated with each.

ANS: Forms of primate locomotion include quadrupedalism (almost any monkey or ape species), brachiation (gibbons and siamangs), semi-brachiators (most apes and also New World monkeys with a prehensile tail), vertical clinging and leaping (lemurs and lorises). Bipedalism may also be mentioned as part of the human species.

REF: Primate Adaptations

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4. List seven traits that distinguish the Anthropoids.

ANS: The book lists thirteen traits: larger body size, large brain, reduced reliance on smell, increased reliance on vision, greater degree of color vision, bony plate at the back of the eye, blood supply differently connected to the brain, fusion of the mandible, more generalized dentition, differences in female internal reproductive anatomy, longer gestation and maturation periods, increased parental care, and more mutual grooming.

REF: A Survey of Living Primates 5. What are the two suborders of Primates?

ANS: They are Strepsirhini and Haplorhini.

REF: Primate Classification 6. Gibbons are said to be adapted for brachiation. What anatomical features allow some primates to be efficient brachiators?

ANS: Anatomical modifications at the shoulder joint to allow rotation, arms longer than legs, short, stable lower back, long curved fingers, and shortened limbs.

REF: Primate Adaptations 7. Compare chimpanzee and bonobo anatomy and social behavior.

ANS: They are less stocky and are smaller, their legs are longer relative to their arms, their heads are smaller, they have a dark face from birth, they are less aggressive and excitable than chimpanzees, and they have frequent copulation outside of estrus and have same-sex sexual activity.

REF: A Survey of Living Primates

Essay Questions 1. What are the main tenets of the visual predation and arboreal theories of primate origins? Discuss the strengths and weaknesses of both.

ANS: Will vary REF: Primate Adaptations 2. What are the adaptations specific to the primate order? In other words, what makes primates an order?

ANS: Will vary REF: Primate Characteristics 3. Compare and contrast the social organization of orangutans, gorillas, and common chimpanzees.

ANS: Will vary REF: A Survey of Living Primates 4. Why are nonhuman primate populations endangered? Why is their extinction of grave concern?

ANS: Will vary REF: Endangered Primates

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5. Discuss the form of locomotion called brachiation. Among which primates is it most commonly found? Why are some primates called “semibrachiators”? Where are semibrachiators found?

ANS: Will vary REF: Primate Adaptations

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CHAPTER 7: PRIMATE BEHAVIOR Chapter Outline I.

Introduction A. This chapter is about what we know and hypothesize about the individual and social behavior of nonhuman primates.

B. Behavior is extremely complex in mammals and birds because it is shaped over evolutionary time.

1. Human behavior is part of this continuum.

2. Behavior in all species is shaped by environmental and physiological variables.

II. The Evolution of Behavior A. Free-ranging primates are studied from an ecological and evolutionary perspective, focusing on the relationship between individual and social behaviors, the natural environment, and various physiological traits of the species. This is called behavioral ecology.

1. Central to this perspective is the hypothesis that all of the interconnected biological components of ecological systems (animals, plants, and microorganisms) have evolved together.

2. Behaviors have evolved through the operation of natural selection and are therefore subject to natural selection in the same way physical traits are. a. In insects and other invertebrates behavior is mostly under genetic control. b. In vertebrates there is a substantial portion of behavior that is due to learning; this is especially true of primates, and humans most of all.

3. From the relatively new field of behavioral genetics (study of how genes affect behavior) we know that behavior must be viewed as the product of complex interactions between genetic and environmental factors. a. To understand the function of one behavioral element, it’s necessary to determine how it is influenced by numerous interrelated factors. (i) Both ecological setting and ancestry have affected behavioral evolution. b. Primates are among the most social of animals and social behavior is a major topic of research. c. Social structure is an interrelated factor, for example; it influences individual behavior and the distinctions between social and individual behaviors are blurred.

B. Some Factors That Influence Social Structure 1. Body Size a. Larger animals require fewer calories per unit of weight than smaller animals. b. Body heat is lost at the surface, larger animals can retain heat more efficiently, so they need less energy overall.

2. Basal Metabolic Rate (BMR) a. Metabolism is the rate at which the body uses energy to maintain all bodily functions while in a resting state. (i) Smaller animals have a higher BMR than larger ones. (ii) Some larger primates with lower BMR can do well with less energy-rich foods (e.g. leaves.)

3. Diet a. Nutritional requirements are related to body size and BMR; all have evolved together. b. When primatologists study the relationships between diet and behavior, they consider the benefits in terms of energy (calories) derived from various food items against the costs (energy expended) of obtaining and digesting them.

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4. Distribution of Resources a. Various kinds of foods are distributed in different ways. b. How species feed on resources depends upon distribution and ease of access. c. Matrilines (one female, her daughters, and their offspring) break up into smaller subunits while feeding.

5. Predation a. Responses to predators depend on body size, social structure, and type of predator. b. Where predation pressure is high and body size small, large communities are advantageous. These may be mulitmale or multifemale groups.

6. Dispersal a. Male dispersal is the most common pattern. b. Individuals who disperse find mates outside their natal group. c. Most dispersals are related to reduced competition between males for mates and the decreased likelihood of close inbreeding.

7. Life Histories a. Life history traits are characteristics or developmental stages that typify members of a given species and therefore influence potential reproductive rates. (i) Shorter life histories are advantageous to species that live in marginal or unpredictable habitats because reproduction can occur at a relatively rapid rate. (ii) Longer-lived species are better suited to stable environmental conditions.

8. Activity Patterns a. Most primates are diurnal. b. Nocturnal primates tend to forage for food alone or in groups of two or three.

9. Human Activities a. All nonhuman primate populations are now impacted by human hunting and forest clearing. b. These activities disrupt and isolate groups, reduce numbers, reduce resource availability, and can eventually cause extinction.

III. Why Be Social?

A. The relationships among ecological variables have yet to be fully understood. Nevertheless, some general principles do seem to apply. a. Multimale and multifemale groups are advantageous where predation pressures are high: (i) Large groups of prey species increase the probability of predator detection and avoidance. (ii) Large-bodied males can join forces to attack or chase predators away.

IV. Primate Social Strategies A. Dominance hierarchies serve to impose order within primate groups by establishing parameters of individual behavior.

1. Usually serve to reduce the amount of actual physical violence.

2. Rank or status is measured by access to resources, including reproductive resources. a. One of the primary potential benefits of dominance is the increased reproductive success of the individual. Not all researchers agree on this point.

3. An individual’s rank may change throughout their lifetime.

4. Males are generally dominant to females in mixed sex groups. a. Males and females maintain separate dominance hierarchies.

5. Primates learn their position in the dominance hierarchy. a. They acquire social rank as they play with their age peers.

B. Communication is any act (scents, unintentional or autonomic, and intentional behaviors) that conveys information to another individual.

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1. High-ranking members express dominance to subordinates or defuse potentially tense situations by the use of mounting behaviors.

2. Submission can be indicated by a crouched position or presenting the hindquarters (for baboons) and sometimes by grooming.

3. Touching, petting, hugging, holding hands conveys reassurance.

4. Displays are elaborate combinations of behavior used to communicate. a. For example, gorillas slap their chest and tear vegetation to threaten.

5. All nonhuman animals use various body postures, vocalizations, and facial expressions to transmit information.

6. Communication is vital vital for social living. Gestures communicate and promote intentions and social relations.

C. Aggressive Interactions are balanced with affiliative behaviors which promote group cohesion.

1. Conflicts may arise out of resource competition and competition for mates and food. a. Intragroup aggression occurs in the form of various signals and displays. b. Sometimes, dominant females intimidate, harass, and attack lower-ranking females; actions can cause weight loss and poor nutrition in low-ranking females. c. Male-male competition for mates can result in injury or death.

2. Aggression is often used to protect resources or territories, although not all primates are territorial.

3. The core area within the home range contains the highest concentration of predictable resources and don’t overlay other groups’ territories.

4. Affiliative behaviors serve to minimize violence and defuse dangerous situations.

5. It is not possible to draw direct comparisons between chimpanzee conflict and modern human warfare; however, there are similar patterns in both species.

D. Affiliation and Altruism 1. Common affiliative behaviors include reconciliation, consolation, and simple amicable interactions. a. Most affiliative behaviors involve various forms of physical contact, e.g. touching, handholding, hugging and among chimpanzees, kissing. b. Caregiving and compassion are evidenced, but it is debated whether they are motivated by empathy. c. Grooming is one of the most important affiliative behaviors. (i) Grooming occurs in a variety of contexts: mothers groom infants, males groom sexually-reproductive females, and subordinate animals groom dominant animals. d. Reconciliatory behaviors are important in chimpanzee and bonobo societies as a means to resolve conflict. (i) Bonobos use sex to ensure group cohesion, to restore peace after conflicts, and to relieve intragroup tension.

2. Altruism is behavior that benefits another while involving some risk or sacrifice to the performer. a. It appears to contain elements of what might be considered empathy. b. The most fundamental altruistic behavior, ubiquitous among mammals and birds, is the protection of dependent offspring. (i) Chimpanzees come to the aid of relatives and friends; female langurs join forces to protect infants from infanticidal males; male baboons protect infants and cooperate to chase predators. (ii) Adopting orphans is a form among capuchins, macaques, baboons, gorillas, and chimpanzees. c. Evolutionary explanations are usually based on the premise that individuals are more likely to perform risky or self-sacrificing behaviors that benefit a relative.

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d. “Reciprocal altruism” emphasizes that performers help others to increase the chances that the recipient might return the favor. This is an alternative explanation.

V. Reproduction and Reproductive Behaviors A. Generally, females are sexually receptive to males only when they are in estrus.

1. Permanent male-female bonds are not common among nonhuman primates. a. Savannah baboons form consortships. These are temporary friendships formed between males and females while the female is in estrus. (i) Chimpanzees and bonobos also form consortships. (ii) Bonobo consortships are unusual in that males and females continue to mate even when the female is not in estrus.

B. Female and Male Reproductive Strategies promote reproductive success.

1. Primates are among the species most k-selected. a. They produce relatively few young and invest considerable parental care in their young. b. The mother tends to carry most of the burden of infant care. c. R-selected species produce large numbers of offspring but invest little or no energy in parental care (e.g. fish, insects, mice and rabbits.)

2. Males and females follow different reproductive strategies. a. Females spend most of their life pregnant, lactating, and/or caring for their infant. (i) Given the energetic demands of being a female, her strategy is to maximize the available resources. b. Males have little investment in rearing of offspring and attempt to produce as many offspring as possible.

C. Sexual Selection usually operates on males, either in the guise of male-male competition or female mate choice.

1. Sexual selection is most common in species in which mating is polygynous.

2. Polygamous species have male competition for females; sexual selection produces dimorphism, especially body size and canine teeth size.

D. Is Infanticide a Reproductive Strategy? Males may increase their own reproductive success by killing infants fathered by other males.

1. This behavior is not advantageous for the species, but it serves to maximize an individual’s own reproductive success.

2. Infanticide has been observed or inferred in Hanuman langurs, and other species such as gorillas, chimpanzees and humans. a. Alternative explanations for these behaviors include competition for resources and human-induced overcrowding. b. DNA evidence, however, tends to support the conclusion that males are acting to increase their reproductive success.

E. Mother, Fathers, and Infants Mother-infant is the basic social unit in primates; except in species in which monogamy or polyandry occurs, males usually don’t directly contribute in the rearing of offspring.

1. The mother-infant bonding process, beginning at birth, isn’t fully understood, but there appear to be predisposing innate factors that strongly attract the female to her infant, so long as she has had a sufficiently normal experience with her own mother a. Monkeys and apes raised in captivity without contact with their own mothers no only don’t necessarily know how to care for a newborn infant; they may reject or even injure it. b. The importance of a normal relationship with the mother has been demonstrated by field and laboratory studies.

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VI.

Primate Cultural Behavior A. Most biological anthropologists consider it appropriate to apply the term culture to many nonhuman primate behaviors.

B. Cultural behavior is learned, but whereas humans actively instruct their young, free-ranging primates tend to learn cultural behaviors through observation.

1. When nonhuman primate infants observe and learn about food items, appropriate behaviors, and how to modify and use objects to achieve certain ends, group-specific or species-specific cultural traditions may emerge that come to typify an entire group or species.

2. Cultural behaviors observed in chimpanzees include tool-use (“termite fishing,” leaf sponges, twig toothpicks, and nut-cracking with stone anvils and hammerstones). a. The use of hammerstones and anvils is restricted to West African chimpanzee groups. b. Chimpanzees exhibit more complex forms of tool use than any other nonhuman primate. c. Chimpanzees seem to show regional variation in types of tools and dietary preferences. (i) Regional variation in tool use and food preferences is similar to human cultural variations.

3. Kanzi, a male bonobo learned to produce sharp stone flakes by smashing a stone onto a floor.

This provides evidence of problem solving abilities. a. Modern human technology has its roots in this and other goal-directed behaviors (such as termite fishing and using hammerstones to crack nuts).

C. Examples illustrate goal-directed activities similar to human technology; non-human primates are not becoming human, however.

1. Becoming human as an evolutionary goal is considered an anthropocentric view.

VII. Language A. The use of language has traditionally been considered a distinctly human trait. Typically, nonhuman animal communication has been described as a system of purely involuntary vocalizations and actions that convey information about the emotional state of the animal.

1. However, vervet monkeys are known to use specific vocalizations to refer to snakes, birds of prey, and leopards. Vervet communication is restricted to the present, not events in the past.

2. A tarsier predation study in Indonesia showed that they distinguished vocalizations based on type pf predator observed.

B. Humans use language; sets of arbitrary symbols in their written and spoken communication.

1. Language has always been thought of as a uniquely human capability.

2. Ape language experiments have begun to raise doubts that only humans possess all the attributes necessary for language. a. Experiments suggest that all the great apes have the capacity to use signs and symbols to communicate: (i) In the 1960s experiments teaching ASL (American Sign Language for the Deaf) to Washoe were a success. Washoe, himself, taught some signs to a peer. (ii) Work with chimpanzees addressed issues and questions related to classes of objects and representational value in language. (iii) Work with bonobos (Kanzi) actually revealed that these animals were able to learn language through indirect observation.

3. It remains evident, though, that apes do not acquire and use language in the same way as humans do. Not all signing apes understand the relationship between symbols and the object, person, or action they are meant to represent.

C. Ape language experiments may suggest clues to the evolution of human language.

1. Current evidence suggests that changes in the preexisting neurological structures, not new structures and novel connections, permitted the development of language.

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2. Communication became increasingly important during the course of human evolution, and natural selection favored anatomical and neurological changes that enhanced our ancestors’ ability to use spoken language.

3. Language capabilities appeared with the wise dispersal of modern Homo sapiens 100,00030,000 years ago; conversely some favor an earlier origin, 2 million years ago with the genus Homo.

VIII. The Primate Continuum A. Humans tend to view themselves as being separate from the rest of the animals; although we have some unique attributes, we are, in fact, part of a biological continuum.

1. The behavioral differences that we observe between ourselves and chimpanzees and bonobos are mostly quantitative rather than qualitative.

2. Humans, chimpanzees, and bonobos all have functionally similar neurological processes, the same need for bonding and close physical contact, the same developmental stages and dependences on learning.

Key Terms and Concepts Affiliative behaviors, p. 168 Altruism, p. 172 Anthropocentric, p. 182 Autonomic, p. 167 Behavior, p. 160 Behavioral ecology, p. 160 Biological continuum, p. 186 Communication, p. 167 Core area, p. 169 Displays, p. 168 Dominance hierarchies, p. 166 Ecological, p. 160 Empathy, p. 170 Grooming, p. 167 Intragroup, p. 168 K-selected, p. 173 Language, p. 182 Life history traits, p. 164 Matrilines, p. 163 Metabolism, p. 162 Polyandry, p. 176 Polygynous, p. 174 R-selected, p. 173 Reproductive strategies, p. 173 Sexual selection, p. 174 Social structure, p. 162 Territories, p. 169

Lecture Suggestions 1. It is difficult for students to conceptualize the range of primate behaviors without seeing them.

Unless you have a top-quality zoo nearby, observing primate behavior in a zoo setting (with unnatural group sizes and compositions) is not particularly informative for students. There are a number of

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good videos available that demonstrate primate behavior in the wild, such as Among the Wild Chimpanzees, available through the Jane Goodall Institute (http://www.janegoodall.org).

2. The chapter discusses issues such as empathy, compassion, and altruism. Ask students to consider what these emotional responses might look like in animals. You may also want to view the TED talk by noted primatologist, Dr. Frans de Waal on animals and morals at: https://www.ted.com/talks/frans_de_waal_do_animals_have_morals?language=en 3. Develop a debate format in class to discuss issues such as infanticide, aggressive displays and dominance hierarchy, as well as altruism and compassion. What are the social advantages and disadvantages that might accompany each of these behaviors?

4. Discuss the capability of vervet monkeys too use specific vocalizations to refer to particular categories of predators, such as snakes, birds of prey, and leopards. Use The Animal Communication website http://acp.eugraph.com/monkey/index.html and the interactive website and http://primatology.net/2011/03/16/the-semantics-of-vervet-monkey-alarm-calls-part-ii-theexperiment/

Internet Exercises 1. Go online to The Jane Goodall Institute at: http://www.janegoodall.org/ to find out more about chimpanzee behavior. There are numerous resources available from that site.

2. Visit the interactive Smithsonian National Museum of Natural History website, “What Does it Mean to be Human,” http://humanorigins.si.edu/evidence/behavior/primate.

3. Nonhuman primates and language has been a significant area of research over the last 40 + years.

There are many sites available. For Koko the gorilla, see http://www.koko.org/; for Kanzi the bonobo, see multiple sites, including https://www.youtube.com/watch?v=jKauXrp9dl4 and https://www.youtube.com/watch?v=wRM7vTrIIis.

Multiple Choice Questions 1. Studies of nonhuman primate behavior: a. have no relevance for understanding human behavior. b. may provide valuable insights into human behavioral evolution. c. have never been carried out among wild animals. d. offer familiar examples of individual and social behaviors but are not helpful understanding biological continuity between humans and apes. e. provide direct evidence of a monkey ancestor to humans.

ANS: b REF: Introduction 2. Primate behavior is best viewed as: a. influenced by environmental factors. b. entirely genetic in origin. c. independent of environmental factors. d. entirely learned and without any genetic basis. e. subject to very few factors.

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ANS: a REF: Introduction 3. ___________ is the study of the evolution of behavior, emphasizing the role of ecological factors as agents of natural selection. a. Sociobiology b. Biological-ecology c. Behavioral ecology d. Evolutionary ecology e. Eco-sociobiology ANS: c REF: The Evolution of Behavior 4. The chemical process within cells that break down nutrients and release energy for the body to use is called: a. altruism. b. evolutionary biology. c. life history trait. d. metabolism. e. photosynthesis.

ANS: d REF: The Evolution of Behavior 5. According to proponents of behavioral ecology: a. individuals always act to enhance the survival of their species. b. infanticide is beneficial to the social group. c. individuals consciously behave in ways that ensure their fitness. d. behaviors have evolved through the operation of natural selection. e. individuals choose certain environments based upon the likelihood of carrying out aggressive behavior.

ANS: d REF: The Evolution of Behavior 6. Ecological factors influencing primate social behavior include which of the following? a. The distribution of food and water, predators, and nutritional value of foods b. Levels of testosterone among predators c. Ancestry of primates d. Gene codes for behaviors e. Learning ANS: a REF: The Evolution of Behavior 7. A matriline would consist of: a. one female, her daughters, and their offspring. b. one male with multiple females and their offspring. c. an extended family of three or more generations. d. a mother, her sisters, and their offspring.

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e. a grandmother and her sons and their offspring.

ANS: a REF: The Evolution of Behavior 8. ______ dispersal is the most common pattern in mammals, including primates. a. Female b. Male c. Elder d. Offspring e. Adult ANS: b REF: The Evolution of Behavior 9. Primate groups composed of several adult males and females are advantageous in areas where: a. there are few sleeping sites. b. humans are active. c. primates are crepuscular. d. predation pressure is high. e. predation pressure is low.

ANS: d REF: Why Be Social?

10. In the context of social groups, dominance hierarchies: a. are maintained by females only. b. are maintained by males only. c. are not present in any primate species. d. impose a certain amount of order within the group. e. have not been studied by primatologists.

ANS: d REF: Primate Social Strategies 11. Which of the following statements is not true? a. Adult primate males tend to be dominant over females. b. Dominant individuals appear to have priority access to desired food items. c. High-ranking females probably have higher reproductive success than subordinate females. d. Dominance hierarchies create aggression and do not create order within primate societies. e. In groups containing a number of females associated with one or several adult males, the males are generally dominant to females.

ANS: d REF: Primate Social Strategies 12. Some of the deliberate nonhuman primate behaviors that serve as communication include all of the following except: a. spoken language. b. facial expressions. c. vocalizations.

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d. displays. e. interactions.

ANS: a REF: Primate Social Strategies 13. Mounting as an expression of dominance in baboons is believed to also serve to: a. indicate sexual preference. b. defuse tense situations. c. indicate aggression. d. indicate a threat. e. submission.

ANS: b REF: Primate Social Strategies 14. What is chest slapping by gorillas an example of? a. Reassurance gesture b. Submission c. Display d. Involuntary behavior e. Affiliative behavior ANS: c REF: Primate Social Strategies 15. Amicable behaviors that promote group cohesion are called _______ behaviors. a. cultural b. philopatric c. ritualized d. affiliative e. autonomic ANS: d REF: Primate Social Strategies 16. Grooming accomplishes all except: a. plays an important role in the day-to-day life of nonhuman primates. b. is an affiliative behavior. c. occurs in a variety of contexts. d. reinforces social relationships. e. proves empathy.

ANS: e REF: Primate Social Strategies 17. Across many primate species grooming is used to do all of the following except: a. comb and clean an individual’s fur. b. provide reassurance to another individual. c. indicate submission to another individual. d. reinforce existing social relationships.

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e. create a threatening posture that will lead to aggression.

ANS: e REF: Primate Social Strategies 18. Social relationships are crucial to nonhuman primates for all of the following reasons except: a. individuals support each other against outsiders. b. alliances can be used to enhance the status of members. c. resources can be better protected. d. order can be imposed by allowing individuals to attack each other. e. it creates a social basis for predator avoidance.

ANS: d REF: Primate Social Strategies 19. Altruism is a behavior that: a. benefits another while involving some risk to the performer. b. benefits the performer while involving risk to another individual. c. benefits both the performer and another individual while involving risk to both. d. is not common among primates. e. creates potential risk to dependent offspring.

ANS: a REF: Primate Social Strategies 20. Chimpanzee caregiving behaviors are evidenced in: a. subjecting victims to attack. b. helping younger siblings. c. leaving the ill or dying to go hunting. d. leaving orphans, ensuring that they do not become burdens to the group. e. the complete lack of altruism.

ANS: b REF: Primate Social Strategies 21. In Old World monkeys, the swelling and changes in the color of the skin surrounding the female’s genital area is a(n): a. sign of aggression. b. indication of a diseased state. c. indication of estrus. d. a visual cue of a female’s readiness to become aggressive. e. sign also found in all monkeys.

ANS: c REF: Reproduction and Reproductive Behaviors 22. Permanent male-female bonds are: a. common among nonhuman primates. b. not common among nonhuman primates. c. the basis of monogamous pairing typical of all nonhuman primate species. d. nonexistent in primates.

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e. known only in orangutans.

ANS: b REF: Reproduction and Reproductive Behaviors 23. The term for a mating system in which males, and some cases females, have several mating partners is: a. estrus. b. sexual selection. c. polygynous. d. monogamous. e. r-selected.

ANS: c REF: Reproduction and Reproductive Behaviors 24. In bonobos, males and females: a. commonly form friendships and consortships. b. never interact except when a female is in estrus. c. are not usually sexually active outside of the female’s estrus cycle. d. always interact aggressively. e. always avoid one another.

ANS: a REF: Reproduction and Reproductive Behaviors 25. What does k-selection refer to? a. Species that produce large numbers of offspring and invest little to no parental care b. Species that become extinct after a few generations c. Species that produce relatively few offspring but invest a large amount of parental care d. Only egg-laying species e. All species except primates ANS: c REF: Reproduction and Reproductive Behaviors 26. Species producing relatively large numbers of offspring and investing little parental care are: a. k-selected. b. r-selected. c. p-selected. d. alloparental. e. sympatric.

ANS: b REF: Reproduction and Reproductive Behaviors 27. R-selected species include which of the following? a. Mice b. Chimpanzees c. Gorillas

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d. Wolves e. Dogs ANS: a REF: Reproduction and Reproductive Behaviors 28. Female primates: a. assume most of the responsibility for infant care. b. have the same nutritional requirements as males. c. use the same strategies as males for avoiding predators. d. spend almost one-half of their lives pregnant or lactating. e. are the same size as males.

ANS: a REF: Reproduction and Reproductive Behaviors 29. Infanticide by adult males: a. is rare in primates. b. appears to serve no function. c. is performed as the only means of population control. d. is not resisted by females, including the mother. e. has been reported for a number of primate species.

ANS: e REF: Reproduction and Reproductive Behaviors 30. What is the basic primate social unit? a. The mother and infants b. The father and infants c. The male and female d. Sibling relationships e. The mother and the mother’s mother and sister ANS: a REF: Reproduction and Reproductive Behaviors 31. Monkeys raised without mothers in captivity: a. were able to form lasting affectionate ties. b. displayed completely normal parenting behaviors as adults after a few years. c. displayed normal sexual behavior. d. did not know how to care for infants. e. were socially normal as adults, provided they received adequate nourishment.

ANS: d REF: Reproduction and Reproductive Behaviors 32. Cultural behavior: a. has never been observed in nonhuman primates. b. is learned. c. is purely genetic.

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d. has only been observed in chimpanzees. e. has only been observed in bonobos.

ANS: b REF: Primate Cultural Behavior 33. Potato-washing behavior has been observed in which of the following? a. Japanese macaques b. Albanian macaques c. Japanese gorillas d. Chimpanzees e. Vervets ANS: a REF: Primate Cultural Behavior 34. Cultural behaviors observed in wild chimpanzees include the following except: a. stone-tool production. b. the use of “leaf sponges.” c. “termite fishing.” d. twigs used as toothpicks. e. language.

ANS: e REF: Primate Cultural Behavior 35. The traditional view of nonhuman communication has been that nonhumans, including primates: a. are capable of conveying information about the external environment and their emotional state. b. use symbolic communication commonly. c. use language in the same manner as humans. d. can convey information about events in the past and future. e. communicate information relating to their emotional state only.

ANS: e REF: Language 36. According to the current evidence discussed in the text, which of the following statement is true? a. Humans are the only species capable of conveying information pertaining to specific components of the external environment. b. Nonhuman primates can communicate any information except that which pertains to their emotional state. c. Some nonhuman primates appear to give specific alarm calls that refer to particular categories of predators. d. Free-ranging monkeys and apes use symbolic language in the same manner as humans. e. Some monkeys communicate about past and future events by means of symbolic gestures.

ANS: c REF: Language 37. Vervet monkey vocalizations: a. are involuntary responses to external stimuli.

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b. c. d. e.

are voluntary responses to external stimuli. refer solely to the emotional state of the individual. include information about past and present events. are impossible to record and study.

ANS: b REF: Language 38. Human language can be characterized by all of the following except: a. it uses a set of written and/or spoken symbols. b. it is associated with significant neurological changes. c. it is a system of communication with infinite creativity. d. it involves social and cultural learning and refers to internal and external stimuli. e. it evolved directly from nonhuman primate communication and proves common ancestry.

ANS: e REF: Language 39. Linguistic symbols are said to be ________ because they do not resemble the object or concept they represent. a. autonomic b. deliberate c. arbitrary d. closed e. innate ANS: c REF: Language 40. Which of the following have been taught to use sign language? a. Baboons b. Chimpanzees and bonobos c. Macaques d. Lemurs e. Vervets ANS: b REF: Language 41. Which of the following statements is not correct? a. Humans are part of a biological continuum with other animals. b. Human uniqueness is reinforced by a prevailing lack of knowledge about other species. c. Where humans fit into the biological continuum depends on the criteria used. d. Understanding the primate biological continuum helps us understand our own evolution. e. Our differences with other animals are primarily qualitative and not quantitative.

ANS: e REF: The Primate Continuum

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True/False Questions 1. Scientists who use the behavioral ecology approach believe that primate behaviors have evolved through the operation of natural selection.

ANS: True REF: The Evolution of Behavior 2. Large primate groups are advantageous because they increase the likelihood of early predator detection.

ANS: True REF: Why Be Social?

3. All primate communication is autonomic in nature.

ANS: False REF: Primate Social Strategies 4. It has been proposed that male Hanuman langurs that commit infanticide are actually reducing their own reproductive success.

ANS: False REF: Reproduction and Reproductive Behaviors 5. Male-female bonds, such as consortships, are advantageous to females because they gain protection from predators.

ANS: True REF: Reproduction and Reproductive Behaviors 6. Sexual selection does not seem to be an important factor in the evolution of sexual dimorphism.

ANS: False REF: Reproduction and Reproductive Behaviors 7. Chimpanzees have never been observed to modify twigs for termite fishing before actually arriving at the termite mound.

ANS: False REF: Primate Cultural Behavior 8. Kanzi the bonobo learned to produce sharp flakes by throwing rocks to the ground.

ANS: True REF: Primate Cultural Behavior 9. The modification of natural objects for use as tools has several implications for nonhuman primate intelligence.

ANS: True

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REF: Primate Cultural Behavior 10. Several language experiments with chimpanzees, orangutans, gorillas, and bonobos have shown that all great apes have the capacity to use signs and symbols to communicate. Questions, however, have been raised about this type of research.

ANS: True REF: Language

Short Answer Questions 1. What is behavioral ecology?

ANS: It is the study of the evolution of behavior, emphasizing the role of ecological factors as agents of natural selection.

REF: The Evolution of Behavior 2. List and discuss four factors that affect the social structure of a given species.

ANS: Answers will vary but should include discussion of four of the following: body size, basal metabolic rate, diet, distribution of resources, predation, dispersal, life histories, activity patterns, and/or human activities.

REF: The Evolution of Behavior 3. What are dominance hierarchies and what important functions do they serve?

ANS: They are systems of social organization wherein individuals within a group are ranked relative to one another. They reduce the amount of physical violence within a group, allow greater reproductive access for higher ranks (usually), and enhance learning within the group.

REF: Primate Social Strategies 4. Discuss the traditional evolutionary explanation of infanticide in Hanuman langurs.

ANS: Traditionally, infanticide has been explained as a result of a new male killing young offspring of another male so that the female will come into estrus and allow him to mate and produce his own genetic offspring.

REF: Reproduction and Reproductive Behaviors 5. Contrast autonomic responses/behaviors with intentional behaviors as forms of communication.

ANS: Autonomic responses are those that are involuntary and unintentional (chemical responses) and intentional behaviors are considered and acted upon.

REF: Primate Social Strategies 6. What altruistic behaviors have been observed in nonhuman primates?

ANS: There are many examples but the most common are chimpanzees coming to the aid of relatives and friends, langurs protecting females and offspring under attack by infanticidal males, male baboons protecting young from predators, and adoption of orphans within several different species.

REF: Primate Social Strategies

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7. Why do we say that humans are part of a biological continuum?

ANS: Biological continuum is a concept that refers to the fact that organisms are related through common ancestry and have varying degrees of similar behavior because of that ancestry. Humans are said to be part of this because our behaviors are primarily a different of degree only from other animals.

REF: The Primate Continuum 8. Define the terms k-selection and r-selection. Which one is associated with primates? Why? ANS: K-selected refers to species that have few offspring and high levels of parental investment, while r-selected are the opposite. Primates are k-selected because they spend a great deal of time caring for and raising offspring individually.

REF: Reproduction and Reproductive Behaviors

Essay Questions 1. Why do most biological anthropologists consider it appropriate to discuss cultural behaviors in nonhuman primates? Discuss a few examples of these behaviors.

ANS: Will vary REF: Primate Cultural Behavior 2. Discuss the factors that influence primate social structure. What similarities and differences can be drawn between nonhuman and human primate social structures?

ANS: Will vary REF: The Evolution of Behavior

3. Do you think apes have language? Discuss some of the questions that have been raised and what research has demonstrated.

ANS: Will vary REF: Language 4. What are the advantages of being social for primates?

ANS: Will vary REF: Why Be Social?

5. What are the benefits of studying nonhuman primates in wild environments, as opposed to captive environments? What is the greatest challenge facing physical anthropologists conducting primate research today?

ANS: Will vary REF: The Evolution of Behavior

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CHAPTER 8: PRIMATE AND HOMININ ORIGINS Chapter Outline I.

Introduction A. Definite hominin presence in Africa after 7 mya, emphasizing the biocultural nature of human evolution: 1. Earliest hominins are confined to Africa.

2. Their descendants dispersed out of Africa into other areas of the Old World.

II. Early Primate Evolution A. Primate roots go back to the Paleocene 65-56 mya.

B. Earliest primates evolved from more distant mammalian ancestors.

1. The further back in the fossil record, the more primitive and generalized the fossil primates become and the more controversy surrounding classification.

2. These forms, called the plesiadapiforms, possess distinctly related primate features.

3. Quite complete fossils found recently in Wyoming and Montana.

C. Eocene Primates are from the Eocene epoch (56-33 mya) number more than 200 species and show clearly derived primate features.

1. Fossils have been found in North America and Europe, extending into Asia and Africa.

2. Darwinius masillae, from the Messel site in Germany, dates to 47 mya, but unlikely to provide direct evidence of connection to humans and other anthropoids.

3. Eocene fossils were primates, widely distributed, and mostly extinct by the end of the Eocene; how they were related to living primates is less certain.

4. However, these Eocene primates clearly indicate that earliest anthropoids evolved in Africa.

D. Oliogocene Primates during most of the Oligocene (33-23 mya) anthropoid remains come from the Fayum in Egypt and are classified as Old World anthropoids.

1. The Fayum anthropoids: a. the genera Apidium, represented by jaws, partial dentition and postcranial remains. (i) Apidium was likely a squirrel-sized arboreal quadruped. b. Aegyptopithecus, about the size of a howler monkey. (ii) It had a small brain and a long snout, and it has no hominoid or Old World monkey derived features. (iii) Lived about 35-33 mya and is generalized enough to be close to the ancestry of both Old World monkeys and hominoids.

2. Divergence of hominoids from other Old World anthropoids came after this time.

E. Miocene Fossil Hominoids have closer connections to apes and humans.

1. The Miocene (23-5 mya) is also called “the golden age of hominoids.”

2. Continental drift during the Miocene altered climatic patterns and created new migration routes: a. The initial stage of the Miocene was warmer than the preceding Oligocene. b. The Arabian Plate “docked” with northeast Africa around 16 mya, allowing African animals direct passage into southwest Asia.

3. There were more forms of hominoids during the Miocene (23-5 mya) than there are today.

4. The Miocene hominoids may be grouped geographically into African, European, and Asian: a. African forms (23-14 mya) include the best-known genus Proconsul from Kenya. b. European forms (16-11 mya) include a number of derived forms not well understood. c. Asian forms (15-5 mya) are the largest and most varied group; best-known is Sivapithecus.

5. There are several important generalizations regarding the Miocene hominoids. a. They are most closely related to the ape-human lineage than to Old World monkeys. b. They are mostly large-bodied hominoids.

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c. d.

Most of the Miocene species are not ancestral to any living form.

Sivapithecus from Turkey and Pakistan has derived facial features that are similar to living orangutans. e. Definite hominids from the Miocene have not yet been indisputably confirmed.

III. Understanding the Human Connection to Other Primates and the Ways We Differ: Biocultural Evolution A. A distinctive behavioral feature of humans is our elaboration and dependence on culture.

B. Human culture, defined in terms of contemporary contexts, is much more than toolmaking: 1. Material culture means the tools humans use, but it is a small portion of the cultural complex.

2. Yet material culture is what is available for study when examining the record of earlier hominins.

3. Probably hominins were using other kinds of tools (other than stone tools) and displaying other cultural behaviors prior to appx. 2.6 mya.

C. The fundamental basis for human cultural success relates directly to our cognitive abilities.

D. Because of the complex nature, we can’t expect culture to always contain the same elements across species (as when comparing ourselves to nonhuman primates) or through time (when trying to reconstruct ancient hominin behavior).

E. Mutual dynamic interactions are at the heart of hominin bicultural evolution.

IV. Discovering Human Evolution: The Science of Paleoanthropology A. Paleoanthropology is multidisciplinary and seeks to reconstruct every possible information concerning the dating, anatomy, behavior, and ecology of hominin ancestors 1. Vertebrate paleontologists find geological beds containing faunal remains.

2. Paleontologists can date fossil sites without chronometric analyses.

3. Material clues as artifacts inform us directly about early hominin activities.

B. The earliest definite hominin tools are stone, dating to about 2.6 mya.

1. Digging sticks and waterproof gourds leave no trace in the archaeological record.

2. Bipedal lifestyles were a crucial adaptation that allowed humans to carry sticks, gourds, bones, chunks of stone over great distances.

3. Only rocks altered according to a regular pattern are identifiable as real artifacts.

C. Early stone tools are simple, small sharp flakes removed from a rock nodule and made to a standard size and shape.

1. This earliest tool-making industry is called Oldowan industry; it began to be replaced around 1.4 mya with larger, more complex stone tools.

D. One of the essentials of paleoanthropology is placing sites and fossils into a chronological time sequence: scientists use two methods of dating to date the geological settings in which sites are found: 1. Relative dating – older than, younger than: a. Stratigraphy, stratigraphic dating is based on the law of superposition which states that a lower stratum is older than a higher one. (i) Problems include the fact that earth disturbances may shift the strata or materials, making the chronology difficult or impossible to reconstruct and the elapsed time of any stratum cannot be determined with accuracy. b. Biostratigraphy, based on regular changes in the dentition and anatomical structures that allows cross-correlation. c. Paleomagnetism, based on the shifting nature of the earth’s geoomagnetic pole; by examining magnetically-charged particles encased in rock, geologists can determine the orientation of ancient “compass.”

2. Chronometric dating (absolute dating):

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a. Potassium-40 (40Ar) has been extensively used in dating materials in the 5-1 mya range, especially in East Africa where past volcanic activities makes this dating method possible. (i) 40K has a half-life of 1.25 billion years and decays to 40Ar. When rock is heated by volcanic activity, any accumulated 40Ar is driven off. Once the molten rock cools, any 40 Ar gas produced becomes trapped in the rock. The age of the rock is determined by heating it in the laboratory to measure the amount of accumulated 40Ar gas. b. Carbon-14 is the measurement of radioactive decay of an isotope (14C) into another, more stable form: (i) The 14C method is used only on organic materials and has a useful time-range of 75,000 to less than 1,000 years, since the half-life of 14C is only 5,730 years. (ii) The age estimate is based on the fact that 14C decays into another stable isotope. c. Thermoluminescence (TL) used to date inorganic artifacts that have been heated (i). Stone used in tool manufacture contains trace amounts of radioactive elements such as uranium. When the stone is heated certain particles trapped within are released. When they escape, they emit a dull glow known as thrermoluminescence. By heating stone particles archaeologists can measure its thermoluminescence. d. Uranium series dating relies on radioactive decay of short-lived uranium isotopes. e. Electron spin resonance (ESR) is based on measuring trapped electrons.

V. Understanding Our Direct Evolutionary Connections: What’s a Hominin?

A. The earliest hominid traces, dating to the end of the Miocene, consist primarily of dental and cranial pieces.

B. Hominins have been variously defined as having a large brain, bipedal locomotion, and/or toolmaking behavior, characteristics that define what makes a hominin.

1. It is clear that these characteristics did not evolve simultaneously. The phenomenon of different physiological systems evolving at different rates is called mosaic evolution.

2. The most defining characteristic for the entire course of hominin evolution is bipedal locomotion.

C. Members of the human lineage are referred to as hominins (tribe Hominini).

1. The revised classification refers to very close associations between African great apes, humans, and chimpanzees.

2. Hominid no longer is used to refer specifically to humans and now refers to all great apes and humans together.

3. There is some confusion due to these two terms, so this book uses the term hominin exclusively to cut down on confusion.

VI. Walking the Walk: The Bipedal Adaptation A. Among living primates, only hominins have efficient bipedalism.

1. The evolutionary causes of bipedalism remain obscure, but bipedalism has several advantages over quadrupedalism that include: a. Freeing the hands from locomotion. b. Providing better predator detection. c. Providing an efficient means of covering long distances.

B. The mechanics of bipedalism involve numerous modifications of the basic primate quadrupedal body-plan: 1. The most dramatic modifications are in the pelvis. In quadrupeds, the two ossa coxae are elongated and oriented approximately parallel to the spine. In bipeds, the ossa coxae are shorter and broader and oriented more towards the side.

2. The foot must act as a stable support instead of a grasping limb: a. When we walk we use the foot as a prop to land on the heel and push off from the toes.

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b. There were changes to the lower leg to allow full extension of the knee and to keep the legs together during walking.

3. Hominin bipedalism is both habitual and obligate. a. Habitual bipedalism means that it is the standard and most efficient mode of locomotion. a. Obligate bipedalism refers to the fact that that hominins can only walk bipedally.

4. There are various structural modifications for hominin bipedalism, all of which do not come into place until around 4 mya: a. Increased spinal curvature. b. Pelvis was further modified. c. Elongation of the lower limb. d. Angle of weight support from the hip to the knee shifted. e. Realignment of the big toe. f. Restructuring of foot to be a stable platform and less grasping.

VII. Digging for Connections: Early Hominins From Africa A. All the major structural modifications for bipedalism are present in the early hominin skeletons from central East and South Africa, although the environments in these areas are more heavily forested that the later sites where hominins were found.

B. Pre-Australopiths (6.0+-4.4 mya) 1. Toros-Menalla site, Chad, 7-6 mya, classified as Sahelanthropus tchadensis. a. Position of foramen magnum is intermediate between quadrupedal ape and bipedal hominin and may be “possible hominin.” b. Lack of honing complex, a shearing canine/premolar arrangement, is indicative of a derived characteristic of early hominins, according to some experts and others suggest it could have evolved in hominins and other hominoids due to homplasy.

1. Orrorin, Tugen Hills and Middle Awash area of northeastern Ethiopia: a. Postcranial remains indicate bipedal locomotion. b. Best evidence to establish it as a hominin among all late Miocene fossils.

2. Ardipithecus, Middle Awash and Yohannes Haile-Selassie, 5.8-5.2 mya. a. Postcranial remains indicate a well-adapted biped. b. Aramis site fossils (a site in the Middle Awash region of Ethiopia), 4.4 mya: i.

“Ardi” is the earliest hominin for which we have so many different body parts represented. In addition, some 36 individuals at estimated there. ii.

Brain size estimated between 300-350 cm3 no larger than a chimpanzee’s. iii.

Height is estimated at close to 4 feet, with body weight of around 110 pounds. iv.

Shape of ilium shows competent bipedalism, however there are surprises: (a) Big toe is highly divergent and capable of grasping. (b) There are other primitive features that make is structurally distinct from fine-tuned hominins.

C. Australopiths (4.2-1.2 mya) 1. Australopithecus and Paranthropus make up the group of australopiths.

2. They have an established time range of over 3 million years and have been found in all major geographical areas of Africa.

3. They include two major subgroups: one more anatomically primitive and one more derived.

4. Major features that all australopiths share: a. They are clearly bipedal. b. They have relatively small brains. c. They have large teeth, thick to very thick enamel on molars.

5. Earliest are 4.2-3 mya from East Africa now assigned the separate species of Australopithecus anamensis.

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6. Slightly later and at sites in Hadar, Ethiopia and footprints at Laetoli, Tanzania is the species Australopithecus afarensis: a. They are not bipedal in the way modern humans are (had a strolling motion with a rather short stride). b. Materials represent the largest well-studied collection of early hominins. c. Shares more primitive features with late Miocene apes and with living great apes than do later hominins (such as teeth). d. Cranial remains show a mixed pattern. e. Two interesting finds: i.

Best known find is Lucy, who was an Australopithecus afarensis: the upper limbs are longer than in a modern human. ii.

A child at Dikka site (northeastern Ethiopia) indicates curved fingers and limb proportions are not modern. iii.

Discovery at Woranso-Mille in central Afar region places dates of 3.6 mya and was likely a male; in comparison to Lucy, there is indication of a great deal of sexual dimorphism.

7. What makes A. afarensis a hominin? a. It was an efficient habitual biped (as evidenced by footprints at Laetoli, Tanzania). b. They were also clearly obligate bipeds, which would have hampered their abilities to climb. c. They are clearly an evolutionary bridge.

D. Later More Derived Australopiths (3-1.2 mya) 1. Physical changes make them distinct from their immediate ancestors. There are at least three separate lineages: Paranthropus, a later form of Australopithecus, and early Homo.

2. Paranthropus is the most derived of the australopiths: a. They have the largest teeth of all – huge premolars and molars and they show a great deal of chewing specialization. b. Their faces are flatter and their broad cheekbones flare out. c. They have a sagittal crest which is an adaptation for diet of rough vegetable foods. d. The “Black Skull” was found in northern Kenya, with a cranial capacity of only 410cm3 and demonstrates a mosaic of features derived from other Australopithecus hominids (Paranthropus aethiopicus). e. Paranthropus bosei was found in East Africa around 2 m.y.a. (Olduvai and East Turkana) with a cranial capacity ranging from 510 to 530cm3). f. Paranthropus robustus was found in South Africa. i.

It is very similar to its cousin in East Africa, but not as dentally robust. ii.

There is a great deal of controversy over the taxonomic classification of Paranthropus species. iii.

Some researchers prefer to group all of these derived species with Australopithecus because it is possible that the East African and South African forms evolved through homplasy. iv.

These species seem to have disappeared without leaving descendants. g. In South Africa (as opposed to East Africa) there were later discoveries of Australopithecus. i.

The earliest discovery was in 1924 when Raymond Dart discovered the Taung specimen. ii.

Dart published his findings in1925, calling the specimen Australopithecus africanus and many scientists didn’t accept Dart’s conclusions, in part because most scientists believed at the time that the origins of humans lay in Asia, not Africa. iii.

We now know more about the characteristics of A. africanus from ongoing excavations at places like Sterkfontein, South Africa:

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(a) They were large-toothed but not as much as Paranthropus. (b) Adult cranial capacity of about 440 cm3. (c) Dating suggests between 3 -2 mya.

E. New Connections: A Transitional Australopith?

1. Most researchers have assumed that early Homo first evolved in East Africa because the amount of australopith evidence there.

2. Two partial skulls found in Malapa Cave, South Africa may challenge the view, though. They have been assigned to the species, Australopithecus sediba. a. Dated to a little less than 2 mya using paleomagnetic dating. b. Show a fascinating mosaic of more primitive australopith characteristics with a some derived Homo ones: i.

A small brain. ii.

Curved fingers. iii.

A lower anatomy suggesting an unusual swaying type of bipedalism. iv.

Powerful upper limbs suggesting arboreal capacities. v.

Short fingers like Homo. vi.

A more flexible lower spine. vii.

Possible indications of brain reorganization.

VIII. Closer Connections: Early Homo (2+-1.4 mya) A. Fossil discoveries at Olduvai and East Turkana suggest an early Homo. Some scientists argue that Homo was present as early as 2.3 mya in east Africa (Hadar region), but the better-preserved evidence is from the Plio-Pleistocene: 1. The hominin was found at Olduvai Gorge in Tanzania by Louis Leakey.

2. Dated at 1.8 mya.

3. It had a significantly larger brain with estimate for species at 631 cm3 (an increase of about 20 percent).

4. Cranial shape and tooth proportions are distinct from earlier forms.

5. It was named Homo habilis, “handy man” in order to argue two things: a. These were the earliest known Olduvai toolmakers. b. This was the first species named to be within the genus Homo and so was the source of the Homo line.

B. Now we also have East Turkana remains that are classified with early Homo: 1. It has a cranial capacity 775 cm3; however, the face is still robust.

2. Fragments of tooth crowns indicate large back teeth.

3. These remains indicate that an early species of Homo co-existed for several hundred thousand years on the eastern side of Lake Turkana, even while Homo erectus also lived in East Africa.

C. One line of early Homo likely evolved into H. erectus about 1.8 mya; all other species became extinct after 1.4 mya.

IX.

Interpretations: What Does It All Mean?

A. Assigning the numerous genus and species names to fossil hominids is an attempt to make biological sense out of the tremendous morphological variation present in the samples.

B. When we assign fossil specimens to a particular species, we have to be aware of the biological implications, since we are trying to reconstruct once-living animal communities. There is a logical sequence to follow: 1. Selecting and surveying sites.

2. Excavating sites and recovering fossil hominids.

3. Designating individual finds with specimen numbers for clear reference.

4. Cleaning, preparing studying and describing fossils.

5. Comparing with other fossil material.

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6. Comparing fossil variation with known ranges of variation in closely related groups of living primates and analyzing ancestral and derived characteristics.

7. Assigning taxonomic names to fossil material.

8. Publishing results and interpretations in peer-reviewed sources.

C. Seeing the Big Picture the task is not complete, even though we do understand some general patterns. There are several different African hominid genera and species. Speciation was occurring quite frequently. What is the “big picture”?

1. The complete hominid evolutionary record will never be complete, as speciation is a rare event, but there are general patterns: a. Early hominid species had restricted ranges, thus it is likely they each exploited a small area. This would allow for rapid genetic diversification through genetic drift and natural selection and speciation. b. Most of the species appear to have been tied to arboreal habitats. c. With the exception of early Homo, there are few evolutionary trends regarding increases in body size or encephalization. d. All of the early hominids show an ape-like developmental pattern of accelerated growth and development.

2. What pushed this process into a more human direction? This is a major evolutionary jump.

Key Terms and Concepts Aramis, p. 213 Artifacts, p. 200 Australopiths, p. 215 Biocultural. p. 192 Bipedal locomotion, p. 203 Chronometric, p. 200 Culture, p. 198 Faunal, p. 199 Habitual bipedalism, p. 207 Hominins, p. 192 Honing complex, p. 212 Large-bodied hominoids, p. 197 Mosaic evolution, p. 203 Multidisciplinary, p. 199 Obligate bipedalism, p. 207 Oldowan industry, p. 200 Plio-Pleistocene, p. 224 Postcranial, p. 194 Sagittal crest, p. 221 Sites, p. 199 Stratigraphy, p. 201 Stratum, p. 201 Thermoluminescence (TL), p. 202

Lecture Suggestions 1. Many students have difficulty with the concept of mosaic evolution. It is beneficial to spend extra time talking about the fact that not all hominin characteristics evolved at the same time. This can also lead into a discussion of how one determines when we “became” human. Should we consider australopiths to be human, despite their small cranial capacities? Or should we only consider members of the genus

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Homo to be humans? Besides, what criteria should we use to assign fossils to the genus Homo? The point to be made is that “becoming human” was a process of adding different components at different times (e.g., bipedalism, tool use, brain expansion), so defining when our ancestors crossed the threshold into “humanness” is somewhat arbitrary.

2. Bipedalism is a fundamental concept of what it means to be human. Use a skeleton (or slides) to demonstrate from “head to foot” where we find bipedalism written on the human body. Then go over the terms habitual and obligate bipedalism so that students see why these are used to describe this type of locomotion.

3. In order to show students the great quantity of early hominin materials discovered over the past 30 years, bring in an anthropology text from the early 1970s and contrast the amount information presented about the Plio-Pleistocene hominids in the older text with the amount presented in this text.

4. Present and discuss each type of dating and different methods of each. Explain how scientists decide which method to use and how cross-checking dating may lead to combining various methods.

Internet Exercises 1. The Talk Origins Archive is a Usenet newsgroup devoted to the discussion and debate of biological and physical origins. http://www.talkorigins.org/. Follow the link http://www.talkorigins.org/faqs/kneejoint.html, read the article and then answer the following questions. What claim do creationists make regarding the finding of “Lucy’s” knee joint? What are creationists trying to show with this claim?

What is the source of their confusion regarding this claim?

2. See numerous video features with more about the discovery and evolutionary importance of the skeleton of Ardipithecus http://dsc.discovery.com/videos/ardipithecus/.

3. A nice site for a general review of major concepts and anatomical aspects associated with bipedalism is at http://efossils.org/book/what-bipedalism and PBS has a clip about bipedalism at http://www.pbs.org/wgbh/nova/evolution/what-evidence-suggests.html.

Multiple Choice Questions 1. The fossil evidence indicates that the Eocene primates were: a. mostly extinct by the end of the Eocene. b. not widely distributed. c. evidence of a close connection to humans. d. the earliest bipeds. e. water animals.

ANS: a REF: Early Primate Evolution 2. Where have the fossil remains of the Miocene hominoids not been found? a. Africa b. Europe c. Asia d. North America e. Turkey ANS: d Copyright © 2017 Cengage Learning. All Rights Reserved.

REF: Early Primate Evolution 3. Which genus is found in the Fayum and is probably close to the ancestry of both major groups of living Old World anthropoids? a. Apidium b. Sivapithecus c. Australopithecus d. Paranthropus e. Aegyptopithecus ANS: e REF: Early Primate Evolution 4. Remains of hominins that involve parts other than the skull are called: a. phylogenetic. b. endocranial. c. exocranial. d. post-skeletal. e. postcranial.

ANS: e REF: Early Primate Evolution 5. The Miocene hominoids: a. were distributed over much of the New World. b. were all members of the same species. c. displayed little to no morphological variation. d. were all about the size of a house cat. e. evidenced the “golden age of hominoids.”

ANS: e REF: Early Primate Evolution 6. The terms Sivapithecus, Proconsul, and Dryopithecus when applied to different groups of Miocene hominoids are used to refer to a distinction made at what taxonomic level? a. Species b. Genus c. Subfamily d. Family e. Order ANS: b REF: Early Primate Evolution 7. All of the following statements about culture are correct except: a. it is an optional adaptive strategy for all primates. b. culture integrates an adaptive strategy in humans. c. it involves a toolmaking capacity. d. it is a nonbiological adaptation to the environment. e. aspects of culture have been identified in our closest ape relatives.

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ANS: a REF: Understanding the Human Connection to Other Primates: Biocultural Evolution 8. Hominins have been variably defined scientifically as having which of the following? a. A large brain, toolmaking abilities, adaptations for bipedalism b. Toolmaking abilities, but no particular biological adaptations for bipedalism c. A moderately-sized brain, adaptations for quadrupedalism, and biocultural strategies d. A large brain, toolmaking abilities, adaptations for quadrupedalism e. A small brain, no toolmaking abilities, and no adaptations for bipedalism ANS: a REF: Understanding Our Direct Evolutionary Connections: What’s a Hominin?

9. The earliest hominin traces: a. date to the beginning of the Miocene. b. are primarily full skeletons. c. are primarily dental and cranial pieces. d. date to the early-to-mid Eocene. e. are merely shattered bones impossible to identify.

ANS: c REF: Understanding the Human Connection to Other Primates: Biocultural Evolution 10. The term hominin refers to a distinction made at what taxonomic level? a. Tribe b. Genus c. Species d. Subfamily e. Genera ANS: a REF: Understanding Our Direct Evolutionary Connections: What’s a Hominin ?

11. Adaptive advantages of bipedalism include the following except: a. freeing the hands for making and using tools. b. early predator detection. c. more efficient way of covering long distances. d. further refinements to capabilities used for swimming. e. freeing the hands for carrying objects.

ANS: d REF: Walking the Walk: The Bipedal Adaptation 12. Anatomical changes in hominins indicative of habitual bipedal locomotion include: a. feet with opposable big toes for grasping. b. shortening and broadening of the pelvis. c. increased length of arms relative to legs. d. increased length of the spine. e. more flexible and narrow knee joint.

ANS: b

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REF: Walking the Walk: The Bipedal Adaptation 13. Fossil evidence for early hominin foot structure: a. has come from South and East African sites. b. has come from North African sites. c. is totally lacking. d. indicates they were quadrupedal. e. is highly disputed and therefore insignificant in discussions of human evolution.

ANS: a REF: Walking the Walk: The Bipedal Adaptation 14. What have some researchers concluded from the fossil remains of hominin feet from South Africa? a. They indicate obligate quadrupedalism. b. They indicate many forms of hominins spent considerable time in trees. c. They were adapted for quadrupedalism. d. They indicate the big toe could NOT have aided the foot in grasping. e. Remains from hominin feet have not been found in South Africa.

ANS: b REF: Walking the Walk: The Bipedal Adaptation 15. For humans, culture integrates an entire adaptive strategy involving all of the following except: a. cognitive components. b. political components. c. economic components. d. social components. e. biological components.

ANS: e REF: Understanding the Human Connection to Other Primates: Biocultural Evolution 16. The earliest stone tools are dated to approximately: a. 2.6 million years old. b. 29,000 years old. c. 263,000 years old. d. 17.2 million years old. e. 9.4 million years old.

ANS: a REF : Understanding the Human Connection to Other Primates: Biocultural Evolution 17. Before hominins made stone tools, they probably: a. used sticks or other perishable materials. b. had weapons made of metal. c. made tools from ivory and bone. d. used unbaked pottery (coil technique). e. took tools from other nonhuman primates.

ANS: a REF: Understanding the Human Connection to Other Primates: Biocultural Evolution

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18. The current evidence indicates that hominins possessed all the major structural changes necessary for bipedalism by: a. 4 million years ago. b. 7 million years ago. c. 10 million years ago. d. 6 million years ago. e. 1 million years ago.

ANS: a REF: Walking the Walk: The Bipedal Adaptation 19. What is paleoanthropology? a. It is defined as the study of early humans. b. It is practiced by archaeologists and solely involves the study of artifacts. c. It is concerned with fossilized skeletal remains of all living forms, plant and animal. d. It is defined as the study of fossilized non-primate mammals. e. It is practiced by physical anthropologists and involves the study of early human architecture.

ANS: a REF: Discovering Human Evolution: The Science of Paleoanthropology 20. Which of the following methods are not used to identify hominin fossil sites? a. Aerial photography b. Satellite photography c. Geological surveys d. Water reside analysis e. Vertebrate paleontology ANS: d REF: Discovering Human Evolution: The Science of Paleoanthropology 21. Dating methods indicating that something is older or more recent than something else: a. are called chronometric dating methods. b. are called absolute dating methods. c. include the K/Ar method. d. never require stratigraphic information. e. are called relative dating methods.

ANS: e REF: Discovering Human Evolution: The Science of Paleoanthropology 22. What is the dating method that uses the principle that undisturbed underlying geologic deposits are older than overlying geologic deposits? a. Stratigraphic dating b. Paleomagnetism c. Carbon-14 dating d. K/Ar dating e. Fluorine analysis ANS: a

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REF: Discovering Human Evolution: The Science of Paleoanthropology 23. Thermoluminescence can be used on which of the following? a. Heated materials such as burned flint b. Fossilized plants c. Bone d. Sedimentary layers of dirt e. Petrified wood ANS: a REF: Discovering Human Evolution: The Science of Paleoanthropology 24. Relative dating techniques: a. can provide exact dates of fossil material. b. are always accurate to within 500 years. c. are based on the radioactive decay of unstable isotopes. d. include biostratigraphy. e. rely upon stable isotopes.

ANS: d REF: Discovering Human Evolution: The Science of Paleoanthropology 25. Which of the following is not a chromometric dating method? a. C-14 dating b. K-Ar dating c. Electron spin resonance d. Thermoluminescence e. Stratigraphy ANS: e REF: Discovering Human Evolution: The Science of Paleoanthropology 26. _______ relies on identifying changes in the orientation of the earth’s geomagnetic poles. a. Stratigraphy b. Potassium argon dating c. Fluorine analysis d. Biostratigraphy e. Paleomagnetism ANS: e REF: Discovering Human Evolution: The Science of Paleoanthropology 27. _______ make the best samples for the K/Ar dating method. a. Bones b. Stone tools c. Ostrich shells d. Teeth e. Volcanic rocks ANS: e REF: Discovering Human Evolution: The Science of Paleoanthropology

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28. If an isotope has a half-life of 4 billion years, then in 4 billion years what will happen? a. All of the original amount will have decayed. b. A quarter of the original amount will still remain. c. Half of the original amount will still be present. d. All of the original amount will still be present. e. The original amount will have doubled.

ANS: c REF: Discovering Human Evolution: The Science of Paleoanthropology 29. Potassium-40 (40K): a. decays to the gas, argon-40 (40Ar). b. decays to carbon-14. c. has a full-life of 1.25 billion years. d. is the same as carbon-14. e. is destructive and therefore not used by paleoanthropologists.

ANS: a REF: Discovering Human Evolution: The Science of Paleoanthropology 30. Which of the following would be best suited to the carbon-14 dating technique? a. Materials more than 100,000 years old b. Volcanic rock c. Sedimentary rock d. Metals e. Certain organic materials less than 75,000 years old ANS: e REF: Discovering Human Evolution: The Science of Paleoanthropology 31. The oldest possible hominin found to date has been given which genus name? a. Australopithecus b. Sahelanthropus c. Zinjanthropus d. Ardipithecus e. Orrorin ANS: b REF: Digging for Connections: Early Hominins from Africa 32. Where was Sahelanthropus discovered? a. Egypt b. Ethiopia c. Kenya d. Chad e. South Africa ANS: d REF: Digging for Connections: Early Hominins from Africa

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33. Sahelanthropus has an unusual combination of characteristics, including: a. a small braincase, huge browridges, small vertical face, and lack of shearing canine/premolar arrangement. b. a large braincase and huge browridges, large, wide face, and very pronounced and projecting canines. c. a small braincase and small muscle attachments in the rear of the cranium. d. a small vertical face, small browridges, large, muscular face and extended arms. e. a large vertical face and small browridges, and a large braincase.

ANS: a REF: Digging for Connections: Early Hominins from Africa 34. Recently discovered remains from the Tugen Hills, dated to about 6 million years ago, have been placed in which genus? a. Sahelanthropus b. Australopithecus c. Paranthropus d. Ardipithecus e. Orrorin ANS: e REF: Digging for Connections: Early Hominins from Africa 35. The fossil skeleton known as “Lucy” belongs to which species? a. A. africanus b. A. aethiopicus c. H. habilis d. A. boisei e. A. afarensis ANS: e REF: Digging for Connections: Early Hominins from Africa 36. Australopithecus afarensis specimens from Laetoli and Hadar are: a. the largest well-studied collection of early hominins. b. the oldest hominins discovered to date. c. the smallest least-studied collection of early hominins. d. only found in South Africa. e. forms of H. habilis.

ANS: a REF: Digging for Connections: Early Hominins from Africa 37. The hominin fossils from Laetoli (footprints) and Hadar (Lucy) are classified by most researchers as: a. Australopithecus africanus. b. Homo afarensis. c. Homo habilis. d. Australopithecus robustus. e. Australopithecus afarensis.

ANS: e

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REF: Digging for Connections: Early Hominins from Africa 38. _________ may have been contemporaneous with australopiths but had a significantly larger brain. a. A. afarensis b. Aegyptopithecus c. Homo habilis d. A. africanus e. Ardipithecus ANS: c REF: Closer Connections: Early Homo (2+-1.4 mya) 39. By about 2 mya, which of the following was true? a. All hominins were members of the same genus. b. There were one or more species of the genus Homo present in East Africa. c. Modern humans were living alongside australopiths. d. All hominins still lived only in East Africa. e. There was only one hominid species present in Asia.

ANS: b REF: Closer Connections: Early Homo (2+-1.4 mya) 40. By using the designation Homo habilis, what was Louis Leakey not implying? a. There were at least two hominin lineages present at Olduvai Gorge. b. The Homo lineage was distinct from the australopithecines. c. That Homo habilis was more closely related to modern humans than were the australopiths. d. That Homo habilis was more closely related to australopithecines. e. Members of the group were the early Olduvai toolmakers.

ANS: d REF: Closer Connections: Early Homo (2+-1.4 mya) 41. The earliest australopith fossils come from: a. South Africa. b. Asia. c. East Africa. d. North Africa. e. Europe.

ANS: c REF: Digging for Connections: Early Hominins from Africa 42. The task of interpreting early hominin evolution: a. is still not complete. b. does not require a chronological framework. c. does not require assigning taxonomic names to fossil materials. d. is almost impossible. e. is best left to geologists.

ANS: a REF: Interpretations: What Does It All Mean?

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43. The first Homo habilis fossils were found during the 1960s in: a. Olduvai Gorge. b. Tugen Hills. c. Toros Menalla. d. Sterkfontein. e. South Africa.

ANS: a REF: Closer Connections: Early Homo (2+-1.4 mya) 44. The estimated average cranial capacity for Homo habilis is: a. 442 cm3. b. 631 cm3. c. 520 cm3. d. 350 cm3. e. 775 cm3.

ANS: b REF: Closer Connections: Early Homo (2+-1.4 mya)

True/False Questions 1. Some of the late Eocene primates have been found in Asia.

ANS: True REF: Early Primate Evolution 2. Hominin emergence is characterized by the simultaneous appearance of bipedalism, toolmaking behavior, and a large brain.

ANS: False REF: Understanding Our Direct Evolutionary Connections: What’s a Hominin?

3. Because organic materials such as sticks and bones are usually well preserved in the archaeological record, we have good evidence of the earliest stages of hominin cultural modifications.

ANS: False REF: Understanding the Human Connection to Other Primates: Biocultural Evolution 4. Habitual bipedalism refers to the fact that bipedalism is the only form of hominin terrestrial locomotion.

ANS: False REF: Walking the Walk: The Bipedal Adaptation 5. Carbon-14 dating is a relative dating method used to date rocks and minerals.

ANS: False REF: Discovering Human Evolution: The Science of Paleoanthropology 6. All researchers agree that Sahelanthropus is a definite hominin.

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ANS: False REF: Digging for Connections: Early Hominins from Africa 7. The A. afarensis hand, wrist, and foot bones are indistinguishable from those of modern humans.

ANS: False REF: Digging for Connections: Early Hominins from Africa 8. Remains of early genus Homo have been found in both East and South Africa.

ANS: True REF: Closer Connections: Early Homo (2+-1.4 mya) 9. Taung Baby fossil was the earliest evidence scientists found of Australopithecus anamensis.

ANS: False REF: Digging for Connections: Early Hominins from Africa 10. A clear evolutionary picture is possible for organizing all the early hominins.

ANS: False REF: Interpretations: What Does It All Mean?

11. Except for some early Homo individuals, there is very little in the way of an evolutionary trend in increased body size or of marked greater encephalization.

ANS: True REF: Interpretations: What Does It All Mean?

12. Rates of development can be accurately reconstructed by examining dental growth markers.

ANS: True REF: Interpretations: What Does It All Mean?

Short Answer Questions 1. What general conclusions can be drawn regarding the Miocene hominoids?

ANS: These are mostly large-bodied, highly derived and unlikely to be ancestral to any living forms, and questionable still as far as dating and divergence.

REF: Early Primate Evolution 2. Define the term mosaic evolution. List three different anatomical or behavioral hominid traits that demonstrate the nature of mosaic evolution.

ANS: It is a pattern of evolution in which the rate of evolution in one functional system varies from that in other systems.

REF: Understanding Our Direct Evolutionary Connections: What’s a Hominin?

3. What are the primary benefits of bipedalism?

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ANS: It freed the hands to carry things and make tools, allowed better visual predation, and was an efficient means of covering long distances.

REF: Walking the Walk: The Bipedal Adaptation 4. Discuss the mechanics of walking on two legs in terms of the anatomical characteristics of a biped.

ANS: Some of the primary anatomical characteristics are a shorter and broader pelvis extending to the side, elongation of the legs, changes to the big toe, and a shift of weight from the hip to the knee so that the lower limbs can straighten out and provide stability.

REF: Walking the Walk: The Bipedal Adaptation 5. Contrast obligate bipedalism with habitual bipedalism.

ANS: Obligate bipedalism is when it is the only means of hominin terrestrial locomotion and habitual bipedalism is when it is the most common form of locomotion.

REF: Walking the Walk: The Bipedal Adaptation 6. Distinguish relative from chronometric dating.

ANS: Relative dating is when a date is established as younger or older than another known date.

Chronometric dating is also known as absolute dating and establishes a numerical date (with a margin of error).

REF: Discovering Human Evolution: The Science of Paleoanthropology 7. What traits best distinguish Homo habilis from the australopiths?

ANS: They are best distinguished by larger brain, shorter arms, short fingers, a more flexible spine, reorganization of the brain, and tools.

REF: Closer Connections: Early Homo (2+-1.4 mya)

Essay Questions 1. Explain the differences between relative and chronometric (absolute) dating techniques. Give an example of one relative technique and three chronometric techniques.

ANS: Will vary REF: Discovering Human Evolution: The Science of Paleoanthropology 2. What characteristics define a hominin? Discuss which aspects of your definition can be assessed in the fossil record.

ANS: Will vary REF: Understanding Our Direct Evolutionary Connections 3. Discuss the combinations of anatomical characteristics found in Sahelanthropus, Ororrin, and Ardipithecus. Based on these characteristics, should these genera be considered hominins?

ANS: Will vary REF: Digging for Connections: Early Hominins from Africa

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4. What does it mean to be bipedal? Discuss the importance of bipedalism skeletally and taxonomically.

ANS: Will vary REF: Walking the Walk: The Bipedal Adaptation 5. You are a paleoanthropologist planning an excavation at a new hominin site in East Africa that is dated to about 2 mya. What fossil hominin species might you expect to find? What anatomical traits might you use to assign them to specific existing taxa?

ANS: Will vary REF: Digging for Connections: Early Hominins from Africa

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CHAPTER 9: THE FIRST DISPERSAL OF THE GENUS HOMO: HOMO ERECTUS AND CONTEMPORARIES Chapter Outline I.

Introduction A. All the earliest hominins were restricted to Africa.

B. All the hominins found outside Africa are members of the genus Homo.

1. Starting around two million years ago, a new and significantly different hominin, Homo erectus, dispersed out of Africa.

II. A New Kind of Hominin A. For discoveries in Java, China, Europe and North Africa a variety of taxonomic names were suggested.

1. During the early years of paleoanthropology taxonomic splitting was common.

B. Discoveries from East Africa have established the clear presence of Homo erectus by 1.7 mya.

C. H. ergaster fossils from Africa were placed into a separate species; in this text they are grouped (lumped) together.

D. Homo erectus represents a different kind of hominin.

1. Differences in Homo erectus may represent regional population variation.

III. The Morphology of Homo erectus A. Body Size 1. It is estimated that some H. erectus adults weighed well over 100 lbs. and the average height was around 5 feet 6 inches. a. Sexual dimorphism is present particularly among East African specimens. b. The skeleton of H. erectus is also more robust than that of previous hominins.

B. Brain Size 1. Early Homo had cranial capacities ranging from 500 to 800cm3, whereas H. erectus ranged from 700 to 1,250 cm3.

2. However, when the larger body size of H. erectus is considered, H. erectus seems to have been no more encephalized than the larger-bodied sample of early Homo.

C. Cranial Shape 1. The H. erectus cranium has a distinctively shaped, long and low, heavily built cranium. a. The cranial bones are thick, the supraorbital tori are large, and there is a distinct nuchal torus. b. The maximum cranial breadth is below the ear opening giving the cranium a pentagonal shape (viewed from behind).

IV. The Geographical Range of Homo erectus A. The First Homo erectus: Homo erectus from Africa 1. There is evidence which suggests that H. erectus first evolved in Africa. Two pieces of evidence confirm this hypothesis: a. all earlier hominins prior to H. erectus were found in Africa. b. there are well-dated fossils by 1.8 mya at East Turkana, in Kenya and other sites in East Africa.

2. It seems likely that H. erectus first arose in East Africa and then very quickly migrated to other continents, although dating has not confirmed this.

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a. East Turkana: The earliest fossil found in this region is a nearly complete skull (Fig. 9-3), the skull has a small cranial capacity estimated at 848 cm3, and dated to 1.8 mya is the oldest H. erectus ever found. b. Another new find is the smallest cranium of any H. erectus from anywhere in Africa, cranial capacity of 691 cm3, dated around 1.5 mya, possibly a female and indicative of sexual dimorphism. c. West Turkana, Nariokotome: WT 15000, the most complete H. erectus skeleton ever found, was discovered in 1984. (i) The fossil is dated to about 1.6 mya, with cranial capacity 880 cm3 (as an adult it would have been appx. 909 cm3). (ii) The fossil is complete enough to determine the stature at 5’3” and the skeletal age of 8 years. At maturity, this male H. erectus would have been over 6’ tall. d. Olduvai: 1960 Louis Leakey discovered in Tanzania H. erectus skull dated to 1.4 mya. (i) It has the largest cranial capacity of all African H. erectus specimens (1,067 cm3), as well as the largest browridges of any known hominid. (ii) As is typical of most African H. erectus specimens, the cranial bones are thin. e. Gona: in the Gona area in Ethiopia a recently discovered female H. erectus pelvis was found dating to 1.3 mya. (i) This pelvis indicates H. erectus brains were developed in utero and were signs of large-brained babies. f. Daka: A mostly complete 1 mya cranium of H. erectus was discovered recently in the Middle Awash. Significantly, the cranium resembles Asian H. erectus specimens and lends credence to the argument that African and Asian specimens are not separate species.

B. Who Were the Earliest African Emigrants?

1. Recently discovered evidence at Dmanisi in the Republic of Georgia (dating 1.75 mya) challenges the view of an African origin and a migration to other continents.

2. In East Africa Homo erectus appeared around 1.7 mya, yet similar hominins appear around the same time in Indonesia and the Caucus region. a. The three Dmanisi crania are similar to H. erectus, but in one specimen the browridge is less robust and thinner than normal. It also seems to resemble smaller East African early Homo specimens. b. A fourth skull of an older male without teeth, one who would have needed the assistance of others to survive 3. Stone tools were recovered at Dmanisi similar to the Oldowan industry from Africa, as expected for a site earlier than the Acheulian industry. a. The Dmanisi fossils show an interesting combination of traits, such as smaller stature (4’9” to 5’5”) and smaller brain size.

4. Suggests that the first hominins to leave Africa were quite possibly small-bodied very early forms of H. erectus, carrying a typical African Oldowan stone tool culture.

5. Or, there were two migrations out of Africa at this time.

C. Homo erectus from Indonesia 1. Presently, H. erectus fossils have been found at six sites in Java.

2. Eugene Dubois, a Dutch anatomist, discovered the first H. erectus fossils in Java in 1891. a. He initially looked for the “missing-link” in Sumatra in 1887. b. In 1890, he began exploring the deposits around Solo River, near the town of Trinil, Java. c. A 900-cm3 skullcap was found in 1891, and a femur that Dubois claimed belonged to the same individual was found the next year. Many now believe the femur belongs to a modern human.

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3. The Ngandong remains have been recently dated to between 50,000 – 25,000 ya making them contemporaneous with modern Homo sapiens elsewhere in the Old World. a. Generally accepted that these fossils date to the Early to Middle Pleistocene. b. These individuals would have been contemporaneous with H. sapiens.

D. Homo erectus from China 1. A local practice of using “dragon bones” as part of Chinese medicine led scientists to the source of these bones near Beijing at a very important site called Zhoukoudian. a. By 1982, the mostly fragmentary remains of 14 skullcaps, 100 isolated teeth, and other fossil remains were recovered. i. Interpretations for these remains vary from ritualistic treatment, cannibalism, and even the left-over meals of giant hyena. ii. These remains represent up to forty individuals and date about 780,000 years ago. b. The cultural remains include over 100,000 artifacts recovered from layers representing many thousand years of intermittent occupation. (i) The most common tools are chopping tools, but retouched flakes were fashioned into scrapers, points, burins, and awls. There is some evidence for technological evolution through time. (ii) The evidence from Zhoukoudian indicates H. erectus was a hunter-gatherer (scavenger). (iii) Some unsettled questions include whether the cave was actually used as a shelter where H. erectus used and controlled fire, or another interpretation has been that of a vertical shaft that served as a trap for mammals.

2. Other Chinese sites provide clues to the morphology and earliest appearance of H. erectus in China: a. The partial cranium from the site at Lantian County at perhaps 1.15 mya appears to be the earliest evidence for H. erectus in China. (i) There were cranial remains of 2 adult females and fire-treated pebbles and flakes. b. Two badly distorted crania were discovered in Yunxian County, at Hubei province dating around 800,000 to 580,000 years ago. c. There were also finds at Hexian, but dating remains unclear on these remains. d. From the evidence it appears that H. erectus inhabitants had limited hunting capabilities. e. The crania from Java and China share features which could be explained by H. erectus migration from Java to China, ca. 1 mya.

E. Asian and African Homo erectus: A Comparison 1. Homo erectus remains from East Africa show several differences in the cranial shape (browridge and nuchal torus) when compared to the Javanese and Chinese fossils.

2. Some paleoanthropologists suggest that these differences require a new classification, those from Asia labeled H. erectus and H. ergaster for those from Africa. a. These species could have been separate from over 1-million years, leading to such differences.

3. Current consensus is to continue referring to all of these hominids as H. erectus.

F. Later Homo erectus from Europe 1. Both Dmanisi fossils as well as recent discoveries of Atapuerca (Spain) fossils have extended the antiquity of hominins in Europe from 400,000 ya; the fossil evidence is traditionally accepted as the earliest hominin habitation in Europe.

2. Recent discoveries at Atapuerca (from Sima del Elefante) date to 1.2 mya, the oldest in western Europe. These include a partial jaw with a few teeth, resembling Dmanisi fossils and Oldowan-like tools.

3. Gran Dolina is dated to 850,000-780,000 ya and has been controversially placed into another species called Homo antecessor.

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4. The Ceprano skull appears to be H. erectus, but the material from Atapuerca has been assigned to a different species by Spanish researchers. a. The more abundant fossil material that appears after 400,000 ya is generally referred to as “premodern Homo sapiens.”

V. Technological Trends During the Time of Homo erectus A. During the existence of H. erectus, a new tool industry was developed, the Acheulian.

1. Biface had a flatter shape than rounder earlier Oldowan cores 2. First evidence that raw materials were being transported more consistently and for distances 3. In China, evidence of biface tools dates back to 800,000 years ago; Acheulian in southern Asia to at least 1 mya.

4. Although these hominins might have been hunting, as much as 80 percent of their daily calories came from gathering wild plants, tubers, and fruits.

VI. Seeing the Connections: Interpretations of Homo erectus A. The Dmanisi cranial remains indicate that the first early Europeans retained some early Homolike features and had only basic stone tools.

1. These remains also demonstrate that this population had considerable intraspecific variation, begging the question as to whether Homo ergaster is a valid species.

B. The new Daka material weakens the separate species interpretation of H. ergaster.

C. The separate species designation for the material from the Gran Dolina is tentative.

D. It is possible that there were two waves of expansion of Homo erectus from Africa.

E. It was H. erectus that transformed hominin evolution to human evolution.

Key Terms and Concepts Acheulian, p. 243 Dmanisi, p. 241 Nariokotome, p. 240 Nuchal torus, p. 238 Pleistocene, p. 244 Zhoukoudian, p. 244 Lecture Suggestions 1. Emphasize that H. erectus existed for over 1 million years, making it the most successful hominin species known. Point out the relatively short time that modern H. sapiens has been around compared to H. erectus. What might this mean for our species?

2. Remind students that as H. erectus populations expanded out of Africa, the evolutionary forces that were talked about previously (natural selection, gene flow, founder effect, genetic drift, and mutation) were still at work in these populations. Emphasize that it is not surprising that we see some geographic differences among H. erectus populations because as they became more widespread, they encountered different environments and different evolutionary pressures. It is important to keep stressing these concepts as you continue onto archaic Homo sapiens and theories regarding the origins of modern humans.

3. Explain why the “Nariokotome boy,” especially the types of remains found, is so important to our understanding of H. erectus today.

4. Review again for students the differences in scientific classification between lumpers and splitters.

Ask them to consider the diversity within their own classrooms – would they tend to be lumpers or splitters?

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Internet Exercises 1. Go online to the website on Atapuerca at http://whc.unesco.org/en/list/989. Explore the website and explain why paleoanthropologists consider this to be one of the most important hominin sites outside Africa.

2. See how Stone Age toolmakers made the leap from stone flakes to a sophisticated hand axe. Emory archeologist Dietrich Stout recreates prehistoric stone tool making techniques at http://www.youtube.com/watch?v=vmanlBDFfw0.

3. Visit the Smithsonian Museum of Natural History exhibit on H. erectus http://humanorigins.si.edu/evidence/human-fossils/species/homo-erectus. What kinds of fossil diversity do you see exhibited from the evidence included on this site?

4. Read more about Zhoukoudian at the UNESCO website http://whc.unesco.org/en/list/449. What is the current status of this site? What kind of research is occurring at Zhoukoudian today?

Multiple Choice Questions 1. Thus far, there is agreement that all hominins found outside Africa are members of which genus? a. Australopithecus b. Ardipithecus c. Paranthropus d. Homo e. H. erectus ANS: d REF: Introduction 2. Homo erectus represents a different kind of hominin than the more ancient African predecessors. One of the primary reasons is that: a. H. erectus is a step towards being more ape-like. b. it represents an increased body size and robustness. c. it demonstrates less encephalization. d. it demonstrates less variation among regional populations. e. it has higher levels of sexual dimorphism.

ANS: b REF: The Morphology of Homo erectus 3. Homo erectus discoveries from East Africa of firmly dated fossils have established the clear presence of this species by: a. 2.8 mya. b. 1.7 mya. c. 800,000 ya. d. 3.2 mya. e. There are no H. erectus discoveries from East Africa.

ANS: b REF: A New Kind of Hominin 4. Which of the following statements is false? a. Several definite Homo erectus fossils have been discovered in France. b. Earlier Homo erectus populations had a smaller cranial capacity than later populations. c. Thick cranial and postcranial bones characterize most Homo erectus specimens.

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d. Homo erectus appears to have been less encephalized than Homo sapiens. e. Homo erectus was most likely the first hominid to live outside of Africa.

ANS: a REF: The Geographical Range of Homo erectus 5. What is the range for estimated cranial capacities for Homo erectus? a. 400 to 800 cubic centimeters b. 700 to 1,250 cubic centimeters c. 1,000 to 2,000 cubic centimeters d. 1,250 to 1,600 cubic centimeters e. 300 to 750 cubic centimeters ANS: b REF: The Morphology of Homo erectus 6. Homo erectus differs most distinctly from both early Homo and Homo sapiens in: a. the postcranial skeleton. b. bipedal posture. c. height. d. cranial size. e. weight.

ANS: d REF: The Morphology of Homo erectus 7. In general, the cranium of Homo erectus: a. has a high vertical forehead. b. is composed of delicate, thin bone. c. has no brow ridges. d. is virtually identical to that of modern humans. e. has a pentagonal shape when viewed from behind.

ANS: e REF: The Morphology of Homo erectus 8. The earliest of the East African H. erectus fossils came from: a. Nariokotome. b. Dmanisi. c. East Turkana. d. Hexian County. e. Olduvai Gorge.

ANS: c REF: The Geographical Range of Homo erectus 9. A projection of bones in the back of the cranium where neck muscles attach is called a(n): a. sagittal crest. b. nuchal torus. c. sagittal keel. d. fovea centralis.

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e. rhinencephalon.

ANS: b REF: The Morphology of Homo erectus 10. When compared to large-bodied earlier Homo specimens, Homo erectus’ relative body-to-brain size is: a. about the same. b. much smaller. c. about twice as large. d. about 25 percent as large. e. is unimportant in discussions of hominin development.

ANS: a REF: The Morphology of Homo erectus 11. Homo erectus appeared in East Africa between ___ million years ago. a. 1.7 and 1.5 b. 2.5 and 2.3 c. 6.0 and 4.0 d. 3 and 1.0 e. 2.0 and 1.8 ANS: e REF: The Geographical Range of Homo erectus 12. The most complete H. erectus specimen yet found was from: a. Trinil. b. Nariokotome. c. Peking. d. Dmanisi. e. Zhoukoudian.

ANS: b REF: The Geographical Range of Homo erectus 13. Until recently, H. erectus sites outside of Africa all have shown dates later than the earliest finds of species in Africa. This has led paleoanthropologists to assume that: a. the hominins who migrated to Asia and Europe descended from earlier Asian ancestors. b. the sites outside of Africa are misdated. c. the earliest finds in Africa are misdated. d. the hominins who migrated to Asia and Europe descended from earlier African ancestors. e. there is another, heretofore unknown hominin, who is the missing link.

ANS: d REF: The Geographical Range of Homo erectus 14. The Dmanisi site is most notable for which of the following: a. being in North Africa. b. producing crania remains that are uncharacteristic of H. erectus. c. crania with relatively large cranial capacities.

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d. a complete cranium of an older adult with jawbones that show advanced bone loss. e. crania that are not associated with stone tools.

ANS: d REF: The Geographical Range of Homo erectus 15. The cranial remains from Dmanisi have all of the following characteristics except: a. are easily distinguishable from modern Homo sapiens. b. bear some similarities to early Homo specimens from East Africa. c. bear similarities to australopithecine specimens. d. have very small cranial capacities. e. are different from other hominins outside Africa.

ANS: c REF: The Geographical Range of Homo erectus 16. The first Chinese H. erectus discoveries were the result of the focus on locating: a. skullcaps and femurs the same size as remains from Trinil. b. individuals contemporaneous with H. sapiens. c. “dragon bones” used as medicine and aphrodisiacs. d. fossils unhampered by the complex nature of Javanese geology. e. fossils belonging to the late Pleistocene.

ANS: c REF: The Geographical Range of Homo erectus 17. Thus far, what do the postcranial remains of the Dmanisi hominins indicate? a. They are indistinguishable from Homo sapiens. b. They are significantly more robust than other Homo erectus. c. They are much more similar to modern humans than to Homo erectus. d. The first hominins to leave Africa were possibly a very early form of H. erectus. e. They are not bipeds.

ANS: d REF: The Geographical Range of Homo erectus 18. Hominin sites in the European regions of Spain and Italy evidence fossil material that is contemporaneous with Homo erectus. They include all of the following except: a. Sima del Elefante. b. Ceprano. c. Hexian County. d. Gran Dolina. e. Atapuerca caves.

ANS: c REF: The Geographical Range of Homo erectus 19. While many theorists stayed home and debated the merits of natural selection and the likely course of human evolution, this young Dutch anatomist enlisted in the Dutch East Indian Army, having decided to go find evidence of it. a. Eugene Dubois

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b. c. d. e.

Franz Weidenreich Louis Leakey Raymond Dart Richard Leakey

ANS: a REF: The Geographical Range of Homo erectus 20. By far the largest collection of Homo erectus remains have been found at: a. Sangiran. b. Zhoukoudian. c. Olduvai. d. Trinil. e. Lantian.

ANS: b REF: The Geographical Range of Homo erectus 21. Evidence from Zhoukoudian suggests that Homo erectus: a. lived there continuously for over 250,00 years. b. were settled agriculturalists. c. was a scavenger. d. built wooden structures. e. kept domesticated animals.

ANS: c REF: The Geographical Range of Homo erectus 22. At Zhoukoudian, there is now thought to be evidence that Homo erectus: a. killed deer and horses. b. knew how to hunt.. c. used fire inside the cave. d. lived in the cave. e. were victims of hungry giant hyenas.

ANS: e REF: The Geographical Range of Homo erectus 23. The Homo erectus fossils from the Lantian sites in China are dated to______ years old. a. 300,000–200,000 b. 1.65 million–1.54 million c. 500,000 d. 2.3 million–1.8 million e. 800,000–450,000 ANS: b REF: The Geographical Range of Homo erectus 24. Which of the following sites is in China? a. Hexian County b. Atapuerca

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c. Nariokotome d. Gran Dolina e. Olduvai Gorge ANS: a REF: The Geographical Range of Homo erectus 25. The earliest Homo erectus remains from Africa are dated to _____ years ago. a. 2.5 to 3.5 million b. 500,000 to 200,000 c. 800,000 d. 5.5 million e. 1.7 to1 million ANS: e REF: The Geographical Range of Homo erectus 26. The Nariokotome Homo erectus specimen: a. was discovered at Olduvai Gorge. b. is estimated to have been about 65 years old at death. c. is a young female. d. would potentially have reached an adult height of around 6 feet. e. was destroyed in dating analysis.

ANS: d REF: The Geographical Range of Homo erectus 27. The most complete Homo erectus skeleton found to date is the Nariokotome specimen, which includes: a. facial bones and pelvis. b. facial bones, pelvis, and most of the limb bones. c. facial bones, pelvis, most of the limb bones, and ribs. d. facial bones, pelvis, most of the limb bones, ribs, and vertebrae. e. complete skull, pelvis, most of the limb bones, ribs, and vertebrae.

ANS: d REF: The Geographical Range of Homo erectus 28. The term Homo ergaster: a. was suggested to be used to refer to African Homo erectus specimens. b. was suggested to be used to refer to Asian Homo erectus specimens. c. is fully accepted by all paleoanthropologists. d. was initially proposed by Eugene Dubois. e. refers to later H. erectus specimens.

ANS: a REF: A New Kind of Hominin 29. Bifacially flaked tools characterize the _______ stone tool industry. a. Oldowan b. Acheulian

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c. Shewlian d. Osteodontokeratic e. Northern Asian ANS: b REF: Technological Trends during the Time of Homo erectus 30. Evidence for animal butchering is: a. lacking in Homo erectus sites. b. found only in African Homo erectus sites. c. found only in Asian Homo erectus sites. d. widespread in Homo erectus sites. e. found only at Dmanisi.

ANS: d REF: Technological Trends during the Time of Homo erectus 31. The Homo erectus site in Europe that has given paleoanthropologists a unique look at the first possible Homo erectus travelers from East Africa to Southeast Asia is: a. Zhoukoudian. b. Lantian. c. Ceprano. d. Nariokotome. e. Dmanisi.

ANS: e REF: The Geographical Range of Homo erectus

True/False Questions 1. All analyses have shown that Homo erectus hominins represent a different kind of hominin from more ancient African predecessors.

ANS: True REF: A New Kind of Hominin 2. A nuchal torus refers to the projection of bone on the top of the cranium which is very common among Homo erectus.

ANS: False REF: The Morphology of Homo erectus 3. The mean cranial capacity for Homo erectus is 900 cm3.

ANS: True REF: The Morphology of Homo erectus 4. Kamaya Kimeu discovered the most complete Homo erectus at Zhoukoudian.

ANS: False REF: The Geographical Range of Homo erectus

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5. Given the newest dates for the Ngandong Homo erectus material on Java, it is possible that Homo erectus could have existed contemporaneously with Homo sapiens.

ANS: True REF: The Geographical Range of Homo erectus 6. New evidence from Zhoukoudian cave has substantiated the long held notion that Homo erectus used and controlled fire.

ANS: False REF: The Geographical Range of Homo erectus 7. An analysis of the WT 15000 specimen suggests it would only have been about 4 feet tall at maturity.

ANS: False REF: The Geographical Range of Homo erectus 8. The Acheulian biface or “hand axe” is a basic tool of the Acheulian tradition.

ANS: True REF: Technological Trends during the Time of Homo erectus 9. All archaeologists agree that Homo erectus appears to have been an efficient big game hunter who rarely gathered wild plant foods.

ANS: False REF: Technology Trends during the Time of Homo erectus 10. The Dmanisi cranial remains show that the very early European specimens had large brains.

ANS: False REF: The Geographical Range of Homo erectus 11. H. erectus was the first species with a cranial capacity approaching H. sapiens.

ANS: True REF: The Morphology of Homo erectus 12. It now appears likely that cultural traditions relating to stone tool technology were largely equivalent over the full geographical range of H. erectus and its contemporaries.

ANS: True REF: Technological Trends during the Time of Homo erectus

Short Answer Questions 1. List the differences between the cranium and brain size of Homo erectus and modern Homo sapiens.

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ANS: Brain size is larger although so is body size, so the changes are relative. Regarding the cranium, it is thicker and has a projecting nuchal torus, low and receding braincase with little forehead development. It has a more pentagonal shape when viewed from behind.

REF: The Morphology of Homo erectus 2. List the morphological characteristics of Homo erectus discoveries at Dmanisi.

ANS: They have a long, low braincase, wide base, and sagittal keel, but also a thin and less robust browridge, a projecting lower face, and a relatively large upper canine. They also have relatively small cranial capacities.

REF: The Geographical Range of Homo erectus 3. Describe the evidence that suggests the Zhoukoudian was not a hominin habitation site.

ANS: The remains found there are potentially consistent with that of carnivore sites in general. Given the fact that the control of fire at the cave is being questioned, some researchers have cast doubt on whether Zhoukoudian is a hominin habitation site at all.

REF: The Geographical Range of Homo erectus 4. Although Zhoukoudian is the most famous Homo erectus site in China, there are other sites. Name two of these sites and give their dates and significance to paleoanthropological research.

ANS: Three additional Chinese sites are Lantian County (1.65-1.54 million ya), Hexian County (dating unclear), and Yunxian County (800,000-580,000 ya). Significance of these sites is that some are older than Zhoukoudian and they also are potentially different from non-Chinese Homo erectus sites in that the Yunxian appears to have been a population with limited hunting capabilities.

REF: The Geographical Range of Homo erectus 5. Why do some researchers consider the Gran Dolina and Atapuerca hominins to be a different species from Homo erectus? What other species name is also used for these fossils?

ANS: At this point the evidence from these sites is so fragmentary that Spanish scientists have called them Homo antecessor until we know further about them.

REF: The Geographical Range of Homo erectus 6. Describe the attributes and uses of the biface as part of the Acheulian tool kit.

ANS: It includes a core worked on all sides. It is a flatter shape that was used to cut, scrape, pound, and dig. They were primarily used for butchering meat.

REF: Technological Trends during the Time of Homo erectus 7. Explain why the answer to the question “Where did H. erectus first appear?” is not simple.

ANS: There is taxonomic disagreement over how to classify the Asian and African forms. Some scientists separate out the African forms into H. ergaster because of regional diversity.

REF: A New Kind of Hominin

Essay Questions 1. Discuss the differences between Homo erectus remains from East Africa and the Javanese and Chinese fossils.

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ANS: Will vary REF: The Geographical Range of Homo erectus 2. What have scientists been able to ascertain about the Homo erectus lifestyle at Zhoukoudian? What is the nature of the evidence? Include any disagreements within the scientific community.

ANS: Will vary REF: The Geographical Range of Homo erectus 3. Discuss the fossil finds at Dmanisi in terms of their morphology and the information they provide about the dispersal of hominids out of Africa.

ANS: Will vary REF: The Geographical Range of Homo erectus 4. Increased meat consumption is suggested to have led to increased brain and body size in H. erectus and, ultimately, geographic expansion. What implications, if any, does this suggest for modern humans?

ANS: Will vary REF: Technological Trends during the Time of Homo erectus 5. There is some variation among the different geographical groups of highly successful hominins, but anthropologists debate on how to classify them. Why? What are some of the causes of disagreement?

ANS: Will vary REF: The Geographical Range of Homo erectus

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CHAPTER 10: PREMODERN HUMANS Chapter Outline I.

Introduction A. The farther back in time, the less hominins look like modern Homo sapiens.

B. The hominins that appeared after H. erectus were not quite fully modern people, so they are referred to as “premodern humans.”

II. When, Where, and What A. Most “premodern humans” lived during the Middle Pleistocene period, between 780,000 to 125,000 years ago.

B. Some later premodern humans lived well into the Late Pleistocene (125,000-10,000 ya) C. The Pleistocene was a time that saw numerous glaciations and interglacials.

1. There were at least fifteen major and fifty minor glacial advances in Europe.

2. The hominins in Europe, Arica and northern Asia were affected by these climatic oscillations.

3. As ice sheets expanded, the more northern areas of Europe and Asia became uninhabitable.

4. As the climate warmed, migration routes such as the one from Central into Western Europe would have reopened.

D. Dispersal of Middle Pleistocene Hominins 1. Middle Pleistocene hominins were dispersed throughout the Old World, and Europe became more permanently and densely populated.

2. The range of premodern humans did not vastly extend the geographical range of H. erectus, but largely replaced them E. Middle Pleistocene Hominins: Terminology 1. With the exception of Asia, where H. erectus and premodern hominins may have coexisted, premodern humans appear after H. erectus.

2. The major morphological changes relative to Homo erectus are an increase in brain size, a more rounded braincase (maximum breadth is higher up on the sides), a more vertical nose, and a reduction in the angulation of the back of the skull (occipital).

3. There has been disagreement on the taxonomy of these hominins. a. Homo heidelbergensis is used for premodern Middle Pleistocene fossils from Africa and Europe (and some Asian), 850,000 to 200,000 ya. They may or may not represent a fully separate species in the biological sense. b. Archaic Homo sapiens is a terminology that obscures the differences. c. These premodern humans were probably ancestral to modern humans, Neandertal and Denisovans.

III. Premodern Humans of the Middle Pleistocene A. Africa 1. The two most important specimens come from Bodo and Kabwe (Broken Hill). a. The Bodo specimen shows distinctive pattern of cut marks suggesting cannibalism or ritual purposes.

2. Specimens from Africa show a mixture of retained ancestral with more derived (modern) characteristics. They are certainly related to each other. a. The most important of the African finds comes from sites of Florisbad and Elandsfontein (in South Africa).

B. Europe 1. The earliest occurrence of H. heidelbergensis may be the remains from the Gran Dolina at ca.

850,000 ya. However, their taxonomic status is disputed.

2. Other later premodern humans retain many H. erectus traits.

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a. These include Steinheim, Petralona, Swanscombe, Arago, and Atapuerca.

3. Fossils that date to the latter half of the Middle Pleistocene, such as those from Atapuerca (the Sima de los Huesos), show some Neandertal-like traits; as many as 28 individuals, dating to 500,000-400,000 years ago. a. The remains from the Sima de los Huesos have arched browridges and a projecting midface similar to that of Neandertals. b. Sima de los Huesos site contains more than 80 percent of all Middle Pleistocene remains in the world.

C. Asia 1. Specimens from China indicate a great degree of genetic continuity from earlier Chinese H. erectus populations, such as a sagittal ridge and flattened nasal bone. a. Some Chinese researchers hold the controversial view that modern Chinese evolved from a separate Chinese H. erectus lineage.

2. The most complete late Middle or early Upper Pleistocene skull from China is the Dali specimen. The cranial capacity of the Jinniushan partial skeleton (dated to about 200,000 ya.) is fairly large, at about 1,120 cm3, and the cranial walls are thin. It combines both earlier and later morphological traits in premodern humans.

D. A Review of Middle Pleistocene Evolution 1. Middle Pleistocene human fossils from Africa and Europe resemble each other more than either resembles the pre-human fossils from Asia. Thus, the African and European materials are generally referred to as Homo heidelbergensis.

2. Chinese paleoanthropologists argue that contemporary fossils from Asia, such as Jinniushan, should be considered early members of Homo sapiens.

3. The African premodern humans are argued to have evolved into modern humans, the European premoderns into Neandertals, whereas the Chinese premodern humans may have gone extinct.

IV. Middle Pleistocene Culture A. The Acheulian technology of Homo erectus carried over into the Middle Pleistocene.

B. During the later Middle Pleistocene, premodern humans in Africa and Europe invented the Levallois technique, which may reflect their increased cognitive abilities relative to H. erectus.

1. Technique required several complex and coordinated steps.

C. Premodern humans increased their use of cave sites; there is some evidence for the controlled use of fire; and there is also evidence for temporary shelters being built.

D. Numerous resources such as fruits, vegetables, and bird eggs were utilized for food, as was fish.

1. Premodern humans were probably not the accomplished hunters as was once previously thought, given new archaeological reconstructions at Terra Amata. a. Wooden spears, dating around 400,000 ya, were found at the site of Schöningen. It is argued that these are throwing spears that were used for hunting large animals.

V. Neandertals: Premodern Humans of the Late Pleistocene A. Neandertal remains are as old as 130,000 ya, but we usually think of Neandertals as living during the last glaciation (starting 75,000 ya).

1. Specimens from Western Europe are often called classic Neandertals.

2. Neandertals had large brains (1,520 cm3 average) that may be partially explained by their large body size and need for metabolic efficiency in colder climates. a. The Neandertal cranium is large, long, and low with an occipital bun. The forehead is more vertical than in H. erectus, the brow ridges are arched rather than straight, and the face projects distinctly forward.

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b. The postcranial skeleton is robust, and the muscle markings are indicative of powerful musculature. Neandertals have short limbs, a feature that has been interpreted as the product of cold adaptation.

B. Western Europe 1. One of the most important Neandertal discoveries comes from La Chapelle-aux-Saints, a cave in France; individual buried in a shallow grave in a flexed position. a. French anatomist M. Boule incorrectly reconstructed the Neandertal as bent-kneed, misjudging the posture because the adult male skeleton had arthritis of the spine. b. La Chapelle is often depicted as the typical Neandertal when in fact he is extremely robust, even for a Neandertal.

2. The more recent remains of 12 individuals from El Sidrón in northern Spain, dated to 49,000 ya, show evidence of cannibalism. a. Hypothesized to belong to the same social group, a band of hunter-gatherers. b. Males were closely related genetically; females were not.

3. St. Césaire, southwestern France, dated to 35,000 ya recovered with Upper Paleolithic tool industry.

C. Central Europe is a region with a number of important Neandertal sites.

1. Krapina, Croatia, is a site dating to the last Interglacial (130,000–110,000 ya) with the earliest intentional burials and perhaps the earliest appearance of “classic” Neandertal features.

2. Vindija cave, near Krapina, has 35 Neandertal specimens dating from 42,000 to 32,000 ya. (i) Some believe the morphology of these fossils indicates in situ evolution from Neandertals to early modern humans in central Europe. (ii) These are the most recent Neandertal remains yet recovered.

3. Chatelperronian tool industry is associated with these groups—it may represent a borrowing of traits from local modern human populations.

D. Western Asia is another region with a number of important Neandertal sites.

1. Israel sites include Tabun (dating to 120,000 to 110,000 ya) and Kebara (dating to about 60,000 ya).

2. The site of Shanidar, Iraq, has the remains of nine individuals, four of whom were intentionally buried. a. The Shanidar 1 specimen is the skeleton of a 30-45 year-old male who has a healed fracture on the left side of the head, a withered right arm and shoulder (bones of the lower arm and hand are missing), and (among other pathologies) a healed fracture of the right foot. His survival of these injuries has been cited as evidence for compassion among Neandertals.

3. Central Asia a. A 1930s discovery of a Neandertal child and tools of Mousterian industry at Teshik-Tash site (in Uzbekistan) proposed Neandertal dispersion into central Asia. b. Though this was not fully accepted, fragmentary remains from southern Siberia also show a distinctively Neandertal genetic pattern.

4. Fragmentary hominin remains from Denisova Cave dated to 50,000-30,000 ya indicate mtDNA do not match that of either modern H. sapiens or a Neandertal; the entire genome was sequenced, confirming that the Denisovans are genetically connected to some living human populations: a. Suggests that this new hominin line diverged from the modern H. sapiens /Neandertal line about 1 million ya. b. This data confirm that the Denisovans were a third line co-existing with Neandertal and modern H. sapiens.

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VII. Culture of Neandertals A. Neandertals are primarily associated with a Middle Paleolithic stone tool industry called the Mousterian; however, this industry was not unique to Neandertals.

B. Technology Neandertals developed specialized tools for skinning and preparing meat.

1. Neandertals rarely used bone tools.

2. Neandertals were advanced in exploiting new food resources, as well as fashioning personal adornments.

C. Subsistence included hunting, and their sites contain abundant remains of animal bones.

1. Neandertals may not have been as efficient at hunting as later Upper Paleolithic humans. a. They lacked long-distance weaponry, and an analysis of Neandertal skeletal fractures is consistent with up-close hunting methods. b. Paleonathropologists Thomas Berger and Erik Trinkaus compared the pattern of trauma in Neandertals to modern day rodeo performers to illustrate their closeproximity to their prey. c. Expanded their range of available foods to include marine resources D. Speech and Symbolic Behavior most likely included articulate speech, but whether they had the same language capacities as modern H. sapiens is the subject of debate and current scientific inquiry.

1. Upper Paleolithic humans are hypothesized to have possessed some sort of behavioral advantage over Neandertals; whether this was superior language capability, technological superiority, or increased subsistence efficiency is not clear.

2. Most of the reservation about advanced cognitive abilities among Neandertals has been based on archaeological evidence.

E. Burials left behind by Neandertals were intentional. This cultural practice is evident in sites located in Europe and western Asia (Kebara), but contemporary hominids in Africa did not treat their dead in the same way.

1. After 35,000 ya in Europe, burial practices associated with modern H. sapiens become more complex.

2. Most of the assertions of symbolic treatment of the dead are questionable, and only 16 of 20 best-documented Neandertal burials have definite associations of stone tools and/or animal bones with the dead.

VIII.

Molecular Connections: The Genetic Evidence A. Neandertal DNA the mtDNA from Neandertal specimens has been extracted and partially sequenced from twelve different Neandertals fossils between 50,000-32,000 ya.

1. These results indicate Neandertal mtDNA is more different from contemporary Homo sapiens populations than modern populations are from each other.

2. More of the genetic pattern has been determined; the entire nuclear genome of European Neandertals has been sequenced.

3. Neandertal and modern human lineages are remarkable similar, 99.84% identical.

4. Many people today have Neandertal genes.

5. Intermixing occurred sometime between 80,000 and 50,000 ya.

VI. Seeing Close Human Connections: Understanding Premodern Hominids A. There is considerable variation among Middle Pleistocene hominins.

B. Middle Pleistocene hominins reveal general trends.

1. They were transitional between H. erectus and modern H. sapiens.

2. How significant the regional variability displayed is remains debatable.

3. An extreme lumping approach recognizes one species for all premodern humans.

4. Splitters have identified at least two species distinct from H. sapiens, H. heidelbergensis and H. neanderthalensis.

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5. Species names are assigned to highlight distinct positions in hominin evolution, making them more easily identifiable to researchers and cladistics hypotheses more explicit.

Key Terms and Concepts Chatelperronian, p. 270 Flexed, p. 267 Glaciations, p. 254 Interglacials, p. 254 Late Pleistocene, p. 254 Middle Pleistocene, p. 254 Mousterian, p. 272 Upper Paleolithic, p. 268 Lecture Suggestions 1. Our current interpretation of Late Pleistocene fossil and archaeological evidence is the result of the long history of research on the subject of early humans. Compare the view of Neandertals today with what was known from their initial discovery. Refer to Neandertals: Changing the Image of Mankind,

by Trinkaus and Shipman, as an excellent source on the history of research on Neandertals.

2. The degree to which Neandertals were capable of fully articulate speech is a fascinating subject.

Some anthropologists believe that Neandertals were capable of complex speech like modern humans. Others believe that the debate over Neandertals and speech will never end because the soft tissue of the vocal tract cannot fossilize. Identify the site of Kebara, a cave at Mt. Carmel (p. 270), and the discovery of the only Pleistocene hominid hyoid bone belonging to a Neandertal. Use the knowledge that it is virtually indistinguishable from a modern human hyoid bone to raise the question of whether Neandertals had articulate speaking skills. Then refer students to the website http://sjohn30.tripod.com/id1.html for further exploration on the subject.

3. Remind students of how anthropologists have used the fossil record to construct tree-shaped diagrams that show different branches of hominins, which includes humans and human ancestors, split off from one another (refer to Chapter 5). The diagrams tend to proceed in a straight line, from the tree-trunk base of a common ancestor through progressively smaller branches until the species of interest is reached. The Neanderthal data suggests a less systematic process, with emerging species merging back into the lines from which they diverged. View the May 5, 2010 interview with Jim Mullikin, PhD., acting director NIH Intramural Sequence Center detailing the process to sequence the Neandertal genome http://www.genome.gov/27539119.

4. Research on premodern humans can be more confusing than information related to earlier species.

Create discussions in the classroom related to these issues: why does more recent information often create more questions than answers? Why is our understanding of modern humans complicated by the recent ancestry? The advances that DNA brings opens up our perspective widely – what kinds of questions should this cause us to take back into the earlier paleoanthropological record?

Internet Exercises 1. Visit Palomar Community College’s website, a great source of information, maps, and charts about Neandertals (http://anthro.palomar.edu/homo2/mod_homo_2.htm).

2. Visit National Geographic website http://ngm.nationalgeographic.com/2008/10/neanderthals/hall-text to learn about “The Last of the Neanderthals” an article published October 2008 about DNA research on Neanderthal remains. This website offers a short video clip about the article, a copy of the article, photo gallery, and an interactive quiz.

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3. Visit the Smithsonian National Museum of Natural History at: http://humanorigins.si.edu/evidence/human-fossils/species/homo-heidelbergensis http://humanorigins.si.edu/evidence/human-fossils/species/homo-neanderthalensis and critically consider some of the questions listed under “Unknowns.”

4. Go to the website https://genographic.nationalgeographic.com/denisovan/ and answer the question, “Why Am I a Denisovan?” Students can create similar scenarios for Neandertal and earlier human species.

Multiple Choice Questions 1. The Middle Pleistocene is dated at what time period? a. 125,000, 780,000 b. 500,000, 125,000 c. 10,000, 7,000 d. 780,000, 125,000 e. 180,000, 100,000 ANS: d REF: When, Where, and What 2. The ______ epoch has been called the “Ice Age.” a. Pleistocene b. Paleocene c. Pliocene d. Miocene e. Eocene ANS: a REF: When, Where, and What 3. During glacial periods, the climate in Africa became: a. colder. b. warmer. c. more arid. d. more humid. e. subzero.

ANS: c REF: When, Where, and What 4. During glacial peaks, much of western Europe would have been: a. cut off from the rest of Eurasia. b. covered with desert. c. covered with rain forests. d. unaffected. e. completely flooded.

ANS: a REF: When, Where, and What 5. What can be said about the dispersal of Middle Pleistocene hominins?

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a. b. c. d. e.

Many discoveries come from North America.

For the first time, Europe became more permanently and densely occupied.

Presence in Asia is noticeably lacking.

Unlike their H. erectus predecessors, they were widely distributed in the Old World.

Africa was no longer an area of hominin occupation.

ANS: b REF: When, Where, and What 6. Compared to Homo erectus, the crania of the earliest premodern Homo sapiens exhibit a: a. lower forehead. b. more angled occipital region. c. smaller average cranial capacity. d. more rounded braincase. e. less vertical nose.

ANS: d REF: When, Where, and What 7. Africa’s earliest sites of premodern human fossils range from as old as _________ years ago. a. 200,000 b. 400,000 c. 100,000 d. 600,000 e. 35,000 ANS: d REF: Premodern Humans of the Middle Pleistocene 8. Dating to about 850,000 years ago, human fossils from Gran Dolina are placed within Homo: a. erectus. b. habilis. c. neanderthalensis. d. antecessor. e. heidelbergensis.

ANS: e REF: Premodern Humans of the Middle Pleistocene 9. Kabwe, Bodo, Florisbad, Elandsfontein and Laetoli are sites that evidence premodern Homo sapiens and are located in: a. Europe. b. Africa. c. Central Asia. d. China. e. Iraq.

ANS: b REF: Premodern Humans of the Middle Pleistocene

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10. Examples of premodern Homo sapiens crania that show possible evidence of cannibalism in the form of cut marks is best represented at: a. Broken Hill. b. Tabun. c. Bodo. d. La Chapelle. e. Swanscombe.

ANS: c REF: Premodern Humans of the Middle Pleistocene 11. Dated to approximately 500,000-400,000 years ago, the site of _______ has yielded a sample of 4,000 fossil fragments representing about 28 premodern Homo sapiens individuals, more than 80% of all Middle Pleistocene hominin remains in the world. a. Ehringsdorf b. Sima de los Huesos c. Steinheim d. Swanscombe e. Petralona ANS: b REF: Premodern Humans of the Middle Pleistocene 12. Chinese paleoanthropologists argue that Asian premodern human fossils evidence both earlier and later characteristics. The more ancestral traits include: a. very large cranial capacities. b. a sagittal ridge. c. less flattened nasal bones. d. thin walls of the braincase. e. features that unquestionably substantiate that anatomically-modern migrants from Africa displaced local populations.

ANS: b REF: Premodern Humans of the Middle Pleistocene 13. The tool technology of premodern Homo sapiens in the Middle Pleistocene: a. carried over from the Acheulian tools of Homo erectus with little change until near the end of the period. b. continued to be mainly the Oldowan tradition. c. incorporated the sophisticated use of bone and early forms of pottery. d. discontinued the use of stone flakes. e. was the Levallois technique in Southwest Asia only.

ANS: a REF: Middle Pleistocene Culture 14. Remains evidencing Middle Pleistocene culture indicate that premodern Homo sapiens: a. did not build temporary structures. b. did not exploit different food sources. c. had not learned to exploit marine resources. d. presumably hunted large animals, perhaps horses.

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e. lived in caves but not open air sites.

ANS: d REF: Middle Pleistocene Culture 15. Some assumptions about the hunting capabilities of premodern humans have been challenged by an interesting archaeological find at Schöningen. What did they find? a. A bow and arrow b. Wood spears c. 4000 nodules from which spear points were struck d. Use of fire e. Large flakes struck using the Levallois technique ANS: b REF: Middle Pleistocene Culture 16. Intentional Neandertal burial sites have been located at all of the following except: a. Laetoli. b. La Chapelle-aux-Saints. c. Sima de los Huesos. d. Tabun. e. Shanidar Cave.

ANS: a REF: Culture of Neandertals 17. Neandertal fossil remains have been found to reach as far back as _____ years ago. a. 100,000 b. 500,000 c. 65,000 d. 10,000 e. 130,000 ANS: e REF: Neandertals: Premodern Humans of the Late Pleistocene 18. The majority of Neandertal fossils been found in _____________where they have been most studied. a. South America b. Asia c. India d. Africa e. Europe ANS: e REF: Neandertals: Premodern Humans of the Late Pleistocene 19. Neandertal brain size: a. was smaller, on average, than that of modern humans. b. was larger, on average, than that of modern humans. c. was smaller, on average, than that of Homo erectus. d. averaged about 2,500 cm3.

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e. averaged about 1,100 cm3.

ANS: b REF: Neandertals: Premodern Humans of the Late Pleistocene 20. Neandertal crania are characterized by which of the following? a. Small, flat faces b. The absence of brow ridges c. A rounded, smooth occipital area like that seen in modern humans d. A vertical forehead like that seen in modern humans e. A projecting midface ANS: e REF: Neandertals: Premodern Humans of the Late Pleistocene 21. Some Neandertal physical characteristics may have arisen as adaptations to a ______ environment. a. humid b. hot c. cold d. tropical e. high altitude ANS: c REF: Neandertals: Premodern Humans of the Late Pleistocene 22. Neandertal skeletal remains indicate that they extended their range to the east, far into Central Asia, but as yet no remains have been found in: a. Israel. b. Southern Siberia. c. Iraq. d. Uzbekistan. e. China.

ANS: e REF: Neandertals: Premodern Humans of the Late Pleistocene 23. The La Chapelle-aux-Saints skeleton is not a typical Neandertal: a. and therefore not considered to be a Neandertal. b. because it represents what is most likely a deliberate burial. c. because is that of an older male. d. because, as a specimen, it is a nearly complete skeleton. e. because the individual is unusually robust.

ANS: e REF: Neandertals: Premodern Humans of the Late Pleistocene 24. Upper Paleolithic stone tools were found at the French Neandertal site of St. Césaire, dated to _______ years ago. a. 75,000 b. 50,000 c. 100,000

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d. 35,000 e. 65,000 ANS: d REF: Neandertals: Premodern Humans of the Late Pleistocene 25. There is some evidence to suggest that Neandertals accomplished all of the following except: a. experienced injuries while hunting. b. had language capabilities equivalent to modern humans. c. buried their dead. d. were capable of symbolic behavior. e. adapted to a cold environment.

ANS: b REF: Culture of Neandertals 26. The Neandertal site in Croatia that has produced hominin remains showing the full suite of classic Neandertal morphology is: a. La Chapelle-aux-Saints. b. Krapina. c. Shanidar Cave. d. Arago Cave. e. Broken Hill.

ANS: b REF: Culture of Neandertals 27. Shanidar Cave is extraordinary in that one buried individual: a. is the only example of Neandertal remains found in Israel. b. had severe cranial trauma and loss of the use of the right limb and yet lived beyond these trauma, presumably cared for by others. c. is without the right lower arm and hand, demonstrating the results of poor preservation within the fossil record. d. is known because of grave goods to be an ancient member of an extinct social group in Iraq. e. lived to approximately 80 years of age.

ANS: b REF: Culture of Neandertals 28. What is the term for the stone tool technology most often associated with the Neandertals that extended across Europe and North Africa, into the former Soviet Union, Israel, Iran, central Asia and possibly China? a. Mousterian b. Middle Paleolithic c. Early Paleolithic d. Denisovian e. Oldowan ANS: a REF: Culture of Neandertals

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29. Which is not true about the Teshik-Tash remains? a. They show evidence of hybridization. b. The remains are a child not considered at first to be clearly a Neandertal. c. They include tools of the Mousterian industry. d. They have recently been evaluated using DNA analysis. e. They demonstrate dispersion to central Asia.

ANS: a REF: Neandertals: Premodern Humans of the Late Pleistocene 30. The Mousterian stone tool tradition: a. was developed by Homo erectus. b. is associated with Neandertals only. c. is found in Asia only. d. is found in Western Europe only. e. is associated with both Neandertals and modern humans.

ANS: e REF: Culture of Neandertals 31. Since abundant remains of animal bones are found at their sites paleoanthropologists have described Neandertals as: a. successful hunters and efficient mastodon hunters. b. successful small game hunters, but not necessarily successful large game hunters. c. never gathering shellfish. d. less prone to head and neck injuries. e. possessing long-distance weaponry.

ANS: b REF: Culture of Neandertals 32. Mousterian culture evidences all of the following except: a. more complex burials, with the body’s position deliberately modified. b. use of pigment, perhaps as body decoration, and jewelry. c. natural pigments deliberately applied to shells and animal bones. d. clear distinctions between Neandertals and early modern humans. e. an expanded range of foods to include marine resources.

ANS: d REF: Culture of Neandertals 33. Supposed grave goods found in Neandertal burials: a. have been cited as the sole evidence for Neandertal symbolic behavior. b. include bone and stone tools, along with animal bones. c. are found less consistently and in less concentrations than earlier hominin sites. d. suggest the presence of language. e. are not significant as evidence of intentional behavior.

ANS: b REF: Culture of Neandertals

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34. The genetic evidence from Neandertal remains that is used in studying most Neandertal fossils is in the form of: a. ribosomal information. b. nuclear DNA. c. mtDNA. d. all of these. e. none of these.

ANS: c REF: Molecular Connections: The Genetic Evidence 35. One interpretation of the genetic evidence is that the intermixing of the Neandertal and the modern human lineages: a. never occurred. b. occurred between 2 million and 1 million years ago. c. occurred between 80,000 and 50,000 years ago. d. occurred between 690,000 and 550,000 years ago. e. will be impossible to determine.

ANS: c REF: Molecular Connections: The Genetic Evidence 36. The Middle Pleistocene humans are morphologically: a. diverse and broadly dispersed throughout time and space. b. diverse but not broadly dispersed throughout time and space. c. similar and broadly dispersed throughout time and space. d. similar and not broadly dispersed throughout time and space. e. similar and broadly dispersed through time, but not space.

ANS: a REF: Seeing Close Human Connections: Understanding Premodern Humans 37. The sum of the genetic, fossil, and archaeological evidence suggests that Neandertals: a. are closely related to modern humans. b. are a fully separate biological species. c. were probably incapable of fertilely interbreeding with modern humans. d. represent several points in the dynamic process of speciation. e. were not successful hominins.

ANS: a REF: Seeing Close Human Connections: Understanding Premodern Humans

True/False Questions 1. The main effect of fluctuating climates in Africa during the Pleistocene was to change rainfall patterns.

ANS: True REF: When, Where, and What 2. Homo heidelbergensis refers to finds from China dating to between 850,000 and 200,000 years ago.

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ANS: False REF: When, Where, and What 3. Human remains at Sima de los Huesos exhibit very late Neandertal characteristics and are sometimes classified as modern H. sapiens.

ANS: False REF: Premodern Humans of the Middle Pleistocene 4. Chinese archaeologists point out that Chinese premodern H. sapiens specimens show no indications of genetic continuity with modern H. sapiens from China.

ANS: False REF: Premodern Humans of the Middle Pleistocene 5. The premodern human fossils from Africa and Europe are more similar to each other than they are to the hominins from Asia.

ANS: True REF: Premodern Humans of the Middle Pleistocene 6. Premodern Homo sapiens continued to live in caves and open-air sites, but may also have increased their use of caves.

ANS: True REF: Middle Pleistocene Culture 7. Different stone tool industries coexisted in some areas for long periods during the Middle Pleistocene.

ANS: False REF: Middle Pleistocene Culture 8. The evolutionary roots of Neandertals are shrouded in mystery because there are no fossils from western Europe.

ANS: False REF: Neandertals: Premodern Humans of the Late Pleistocene 9. Genetic evidence suggests that Neandertal DNA is remarkably similar to modern humans.

ANS: True REF: Molecular Connections: The Genetic Evidence 10. Chatelperronian was an Upper Paleolithic industry associated with Neandertals.

ANS: True REF: Neandertals: Premodern Humans of the Late Pleistocene 11. Neandertals are a fully separate biological species from modern humans and therefore theoretically incapable of fertilely interbreeding with modern people.

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ANS: False REF: Molecular Connections: The Genetic Evidence 12. Recent genetic evidence confirms that some interbreeding took place between Neandertals and H. sapiens sometime between 80,000 and 50,000.

ANS: True REF: Molecular Connections: The Genetic Evidence

Short Answer Questions 1. Describe the major climatic shifts that occurred during the Pleistocene.

ANS: There were various glaciations making northern areas of Europe and Asia covered in ice and sea levels rose; in Africa the climate became more arid.

REF: When, Where, and What 2. Contrast the morphology of the earliest European premodern Homo sapiens with that of later European premodern Homo sapiens such as Neandertals.

ANS: Earliest premoderns exhibit several H. erectus characteristics: face is large, brows are projected, forehead is low, and in some cases the cranial vault is thick. These signatures decrease in later European premoderns and the brain size increases.

REF: When, Where, and What 3. List and discuss four characteristics of Middle Pleistocene culture.

ANS: Answers include Acheulian technology carried over until the later period when the Levallois technique emerged (flake development), housing in open-air and caves, but also including some temporary dwellings; exploitation of a wide variety of food sources, including marine resources; some possible control of fire, although this is debated; and hunting that involved spears in some cases.

REF: Middle Pleistocene Culture 4. Describe the subsistence strategies of Middle Pleistocene humans.

ANS: They had a varied diet including fruits, vegetables, seeds, nuts, birds’ eggs, and marine life (an innovation in human biocultural evolution). There is some debate about hunting capabilities, but a wooden spear has been found at Schöningen site in Germany to show some evidence of hunting, as well as remains of a cache of horse remains.

REF: Middle Pleistocene Culture 5. Describe the cranial and postcranial anatomy of Neandertal skeletons.

ANS: Brain size was larger than that of H. sapiens today, but the cranium was large, long, low, and bulging at the sides; the occipital bun was bun-shaped and the forehead rose more vertically than in modern humans. Browridges were arched.

REF: Neandertals: Premodern Humans of the Late Pleistocene

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6. Describe the injuries and pathologies evident in the Shanidar I skeleton. What, if anything, does this tell us about Neandertal lifestyle and/or cultural behavior?

ANS: It is a male from 30-45 years old with a crushing blow to left side of face, probably causing blindness, a massive blow to the right side making the right arm withered and useless—this appendage is missing, likely because it atrophied and dropped off or was amputated. That he survived for years afterward indicates that someone was taking care of him. It speaks to the social development of this group.

REF: Neandertals: Premodern Humans of the Late Pleistocene 7. What genetic evidence will help determine when fully human language first emerged? Discuss the importance of this.

ANS: This includes the FOXP2 gene. Mutations on this gene directly affect language ability, so location of this in Neandertal DNA will advance our understanding of language in this group.

REF: Culture of Neandertals 8. Why is it difficult to get a clear evolutionary picture of Middle Pleistocene hominins?

ANS: There were various regional populations and a great deal of diversity within this group. Also, they were transitional between two better-known groups, H. erectus and modern H. sapiens.

REF: Seeing Close Human Connections: Understanding Premodern Humans

Essay Questions 1. Describe what is known about Middle Pleistocene culture. Include information about technology, settlement, and subsistence.

ANS: Will vary REF: Middle Pleistocene Culture 2. Some paleoanthropologists classify Neandertals as Homo sapiens neanderthalensis. Others disagree.

What evidence is used to support these biological and phylogenetic arguments?

ANS: Will vary REF: Seeing Close Human Connections: Understanding Premodern Humans 3. Describe Mousterian technology, subsistence, settlements, and symbolic behavior of Neandertals.

ANS: Will vary REF: Culture of Neandertals 4. What are the molecular connections among premodern humans? What relationships can we presume existed among these various populations given this evidence?

ANS: Will vary REF: Molecular Connections: The Genetic Evidence 5. Discuss the capability to conduct mtDNA analyses of fossil skeletal remains. What contributions to the understanding of what it means to be human might this capability have in the future?

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ANS: Will vary REF: Molecular Connections: The Genetic Evidence

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CHAPTER 11: THE ORIGIN AND DISPERSAL OF MODERN HUMANS Chapter Outline I.

Introduction A. Our species numbers over 7 billion individuals with no other living hominins but us.

B. Modern Homo sapiens evolved in Africa around 200,000 ya and then dispersed throughout the Old World.

C. Within 150,000 ya, their descendants expanded as far as Australia (and later into the Americas).

1. These individuals raise several questions: a. Who were they? b. Why were they successful? c. What was the fate of other hominins?

D. The first modern humans, evolving by 195,000 ya, are probably descendants of some of the previously-discussed premodern humans: 1. When did modern humans first appear?

2. Where did the transition first take place? In one region or in several?

3. What was the pace of evolutionary change? How quickly did the transition occur?

4. How did the dispersal of modern humans to other areas of the Old World take place?

II. Approaches to Understanding Modern Human Origins A. The Regional Continuity Model: Multiregional Evolution 1. Most closely associated with Milford Wolpoff and associates.

2. Suggests that certain local populations in Europe, Asia and Africa continued their indigenous evolutionary development from premodern Middle Pleistocene forms to anatomically-modern humans.

3. Answers the question, How did so many different local populations happen to evolve with such similar morphology? a. By denying that the earliest modern H. sapiens populations originated exclusively in Africa. b. By asserting that significant levels of gene flow (migration) between various geographically-dispersed premodern populations were extremely likely throughout the Pleistocene.

4. Through gene flow and natural selection local populations would not have evolved independently from one another; this would have prevented speciation between the regional lineages and maintained human beings as a single, although polytypic, species throughout the Pleistocene.

5. Most recent data suggests that the multiregional models no longer tell us much useful information about the origins of modern humans, nor about dispersal of modern H. sapiens.

B. Replacement Models 1. Emphasize that modern humans first evolved in Africa and later dispersed to other parts of the world, where they replaced hominins already living in the other regions.

2. Complete Replacement a. Developed by Christopher Stringer and Peter Andrews, this model proposes that anatomically-modern populations arose in Africa about 200,000 ya, dispersed from Africa, and replaced premodern populations in Asia and Europe. b. This model assumes that the origin of modern humans was a speciation event, so technically there could be no modern human interbreeding with local non-African populations because they were a different species. Of late, Stringer suggests that even though there may have been potential for interbreeding, apparently very little took place.

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c. New molecular data supports an African origin for modern humans and some mode of replacement elsewhere. d. With the completion of the Neandertal nuclear genome we can conclude that some interbreeding took place, arguing against complete replacement and supporting some form of partial replacement.

3. Partial Replacement Models a. Partial replacement models postulate that modern humans expanded out of Africa, but interbreeding among modern humans and regional premodern populations was modest, 14%. b. Contemporary Africans have no trace of Neandertal genes, suggesting interbreeding occurred after modern humans left Africa, ca. 80,000-50,000 ya. c. An assimilation model proposes that more interbreeding took place, at least in some regions. d. In order to fully explore this model we need more whole-genome DNA from ancient remains, particularly from early modern human skeletons.

III. The Earliest Discoveries of Modern Humans A. Africa 1. Earliest fossil comes from Omo Kibish, southernmost Ethiopia with radiometric dates of 195,000 ya.

2. Fully anatomically-modern forms dating from 120,000 to 80,000 ya come from Klasies River Mouth and Border Cave in South Africa.

3. Fossils from Herto, Ethiopia, were announced in 2003 (although discovered in 1997). a. Though not identical to modern people, the cranial remains are near modern and have been securely dated to 160 to 154,000 ya. b. The dates on this fossil are some of the least controversial for such an old specimen. c. Because they share near-modern characteristics, Tim White and his team have placed these fossils under the subspecies name Homo sapiens idaltu. d. These fossils strongly support an African origin for modern humans.

B. The Near East 1. The sites of Skhūl (130,000-100,000 ya) and Qafzeh Caves (120,000-92,000 ya) in Israel have yielded the combined remains of about 30 individuals of modern morphology (although some specimens retain premodern features). a. If the dates for the Neandertal site of Tabun are 120,000 ya, then Neandertals may slightly predate modern humans in this region, but there is still considerable chronological overlap between these two different forms. b. This has been used to suggest that the region is a likely place where Neandertals and modern humans interbred.

C. Asia 1. Of the seven localities in China that have modern human remains, the most important come from Upper Cave at Zhoukoudian. a. The Upper Cave remains are dated to 27,000 ya, and the fossils remains of modern humans at Tianyuan cave date to 40,000 ya. b. Other finds include a partial skull from Niah cave in Borneo, Indonesia dating back more than 35,000 ya (most likely 45,000-40,000 ya). c. A third early Asian find was discovered in 2008 and includes a human femur dated at 45,000 from the Asian site of Ust’-Ishim. This individual shows admixture with Neandertal at about 2.3 percent. This is the earliest evidence of interbreeding with Neandertal and modern populations. However, this does not show a strong affinity to any modern human populations.

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D. Australia 1. Modern humans already inhabited Sahul, the area including New Guinea and Australia by at least 50,000 ya, and bamboo rafts are suggested to have been used to cross the ocean between islands.

2. The earliest occupations, judging by the archaeological evidence, date to about 55,000 ya: a. The earliest skeletal evidence is from Lake Mungo in southeastern Australia.

Radiocarbon dates and the archaeological context indicate an age of 30,000 to 25,000 ya. a. Kow Swamp remains suggest people lived there between 14,000 and 9,000 ya and were different from the more gracile earlier forms from Lake Mungo. b. New genetic evidence indicates that all native Australians are descendants of a single migration dating back to about 50,000 years ago.

E. Central Europe 1. The earliest anatomically modern Homo sapiens date to 40,000 - 35,000 ya to the Oase Cave in Romania. a. From this site these individuals show Neandertal admixture comprising 6 to 9 percent of the genome. He is estimated to be only four to six generations removed from a Neandertal ancestor.

2. Modern human specimens from Mladeč in the Czech Republic date to about 31,000 ya and exemplify central European early modern humans.

3. A third example is Dolní Vĕstonice dated at 26,000 ya.

F. Western Europe 1. Historically, fossils from this area of the Old World have received the greatest amount of attention when considering theories of modern human origins.

2. The best-known sample of western European H. sapiens is from the site of Cro-Magnon. a. These fossils (the remains of eight individuals associated with an Aurignacian tool assemblage) were discovered in 1868 and date to 28,000 ya.

3. A recently discovered child’s skeleton from the Abrigo do Lagar Velho site in Portugal, dated to 24,500 ya, is argued by Duarte, Trinkaus, and colleagues to display a suite of traits indicative of past admixture of Neandertals and modern humans. This supports the partial replacement model.

IV. Something New And Different: The “Little People” 1. By 25,000 years ago, modern humans had dispersed throughout the Old World. a. There may have been a late surviving population of H. erectus-like humans in Liang Bua Cave, on the island of Flores, east of Java. b. “The Little Lady of Flores,” simply “Flo,” along with approximately 13 others nicknamed as “hobbits.” (i) The more complete female adult skeleton is barely three feet tall with a cranial capacity of only 417cm3; living just 13,000 ya. (ii) Where did they come from? Java is 400 miles away, over open waters of an ocean. (iii) Tools were dated to at least 1 mya, meaning they lived there a long time. (iv) Their unique morphology earned them a new species designation: Homo floresiensis. (v) They may have evolved from ancestors that left Africa before H. erectus. c. How did they get to be so different? (i) Isolation causes rapid divergence; natural selection favored reduced body size as an adaptation to reduced resources. (ii) In their cranial shape, thickness of the cranial bone, and dentition, they most resemble Homo erectus. (iii) Unlikely that the one individual found was afflicted with a severe growth defect. (iv) Insular dwarfing has occurred among other species. DNA sequencing of this population has not yet been done because of poor preservation.

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V. Technology and Art in the Upper Paleolithic A. In Europe, the Upper Paleolithic began about 40,000 ya, and this cultural period is divided into five different industries: Chatelperronian, Aurignacian, Gravettian, Solutrean, and Magdalenian.

B. Starting about 30,000 ya, there was a warming trend that produced tundra and steppe throughout much of Eurasia, creating a “hunter’s paradise” of plentiful large game.

C. The Upper Paleolithic people became very successful, and this period saw the highest human population densities up to that time in Europe and perhaps Africa.

D. Cultural innovations in Eurasia included elaborate burials with grave goods.

E. The warming trend ended about 20,000 ya as the last, most intense period of glaciation began.

F. The Upper Paleolithic is distinguished by the appearance of new tool types as well as the increased use of materials such as bone, antler, and ivory.

1. The spear thrower, or atlatl, as well as barbed harpoons appear during the Magdalenian.

2. The punch blade technique provided abundant standardized blades that were fashioned into a variety of tools such as burins and borers.

3. Loring Brace suggests that with more effective tools and the use of fire allowing for food processing, anatomically modern H. sapiens wound not have required the large teeth and facial skeletons seen in earlier populations.

G. The Upper Paleolithic of western Europe is also famous for the appearance of various forms of art, including the cave art of France and Spain, sculptures, engravings, and “portable art” (engravings on tools and tool handles).

1. Female figurines known as “Venuses” appear in western, central, and Eastern Europe.

H. The function of the famous cave art of Lascaux of southern France and Altamira in Spain is not fully understood. It could have been religious or magical, a form of visual communication, or simply art for the sake of art.

I. The Grotte Chauvet dates to the Aurignacian period (about 35,000 ya) and includes never-beforeseen images of hundreds of animals. This site is considerably earlier than the Magdalenian sites of Lascaux and Altamira.

J. Southern Africa has rock art that is about as old as that found in Europe (Apollo 11 rock-shelter cave, 28,000-26,000 ya).

1. At Blombos cave, bone tools beads dated to 73,000 ya, decorated with ocher fragment.

2. At Pinnacle Point, ocher and microliths were found dating to 165,000 ya.

3. Sibudu (in South Africa) dates to 70,000 ya and has evidence of hafting and possible evidence of snares and traps to catch small animals.

4. Border cave in South Africa also shows a complex of behaviors including notched bones, wooden digging sticks, and bone awls dated at 44,000 ya.

5. Katanda in the Democratic Republic of the Congo has three sites that have yielded finelycrafted bone tools.

6. The bone tools have not been precisely dated, but based on TL, ESR, and U-S methods, they are believed to be about 80,000 ya.

K. Summary of Upper Paleolithic Culture 1. The Upper Paleolithic is the culmination of 2 million years of cultural evolution, adding deliberate burials, body ornamentation, and technological innovations. a. In Europe and central Africa, cultural innovations included big game hunting and new weapons such as the atlatl, the harpoon, and eventually the bow and arrow. Upper Paleolithic humans had body ornaments, needles, tailored clothing, and more elaborate burials.

2. After 10,000 ya, the climate slowly warmed and the glaciers retreated. Animal and plant species were seriously affected and these changes affected humans. Grinding hard seeds and roots became increasingly important, and eventually the domestication of plants and animals ensued.

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Key Terms and Concepts Aurignacian, p. 298 Burins, p. 303 Cro-Magnon, p. 298 Magdalenian, p. 303

Lecture Suggestions 1. Go through each of the stone tool industries and point out the variety in each of the technologies.

How does the technology reveal knowledge about their day-to-day lives?

2. Discuss the various strengths and weaknesses of the models of human origins. Explore who promotes each model and why. Ask students to identify the strengths of each, based upon the site evidence.

3. Discuss the food resources available to early modern H. sapiens. Visit the website http://www.anthropark.wz.cz/animal.htm for images and information.

4. Compare and contrast the types of populations that developed on the islands of Flores and the continent of Australia. Provide more information on the phenomenon of insular dwarfism (and gigantism). See the site http://www.pbs.org/wgbh/nova/evolution/gigantism-and-dwarfismislands.html.

Internet Exercises 1. Visit the Buendia Rockshelter site in Spain, which is dated to the Magdalenian http://www.homepages.ucl.ac.uk/~tcrnide/situation.htm.

2. Read “Hard core and cutting edge: experimental manufacture and use of Magdalenian composite projectile tips” to understand the projectile’s performance characteristics and in both efficiency and durability. http://hal-paris1.archives-ouvertes.fr/docs/00/59/85/40/PDF/Petillon_et_al_2011HAL.pdf 3. Go online to the French Ministry of Culture’s website on Grotte Chauvet http://www.culture.gouv.fr/culture/arcnat/en/ for a virtual tour of the site.

4. Visit the PBS website at http://www.pbs.org/wgbh/evolution/humans/humankind/o.html. Many interactive pages, activities, and articles discussing the evolution of Homo sapiens and the various sites where discoveries have been made.

5. Palomar Community College offers a very informative website with great maps of the regions of occupation of early modern H. sapiens as well as a chart explaining the main models for human dispersal and evolution. http://anthro.palomar.edu/homo2/mod_homo_4.htm 6. Visit the Smithsonian Natural History Museum exhibit on Homo floresiensis http://humanorigins.si.edu/evidence/human-fossils/species/homo-floresiensis.

Multiple Choice Questions 1. According to the most recent evidence, the first modern Homo sapiens evolved in Africa around _______ years ago. a. 200,000 b. 1,500,000 c. 50,000 d. 500,000 e. 5,000,000 ANS: a REF: Introduction 2. According to the Complete Replacement Model, the transition from premodern to modern Homo sapiens:

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a. b. c. d. e.

occurred in several regions of the Old World simultaneously. occurred first in Europe. only occurred once, in Africa. began about 10,000 years ago in Indonesia. began about 100,000 years ago in Asia.

ANS: c REF: Approaches to Understanding Modern Human Origins 3. According to the Complete Replacement Model, anatomically modern Homo sapiens first appeared in Africa and: a. dispersed to Europe where they interbred with local premodern H. sapiens populations. b. migrated to other areas completely displacing all premodern H. sapiens populations without interbreeding with them. c. remained there, without interbreeding, while premodern populations elsewhere evolved more slowly. d. remained there until about around 500,000 years ago. e. remained there by interbreeding with all local regional populations, creating a mosaic of physical features.

ANS: b REF: Approaches to Understanding Modern Human Origins 4. Which of the following has not been proposed as a model to explain the origin of modern Homo sapiens? a. An origin in Africa followed by migration to other areas where indigenous premodern populations were replaced. b. An origin in Africa followed by migration to other areas where both interbreeding and replacement occurred. c. Several origins in different areas where modern forms evolved from local populations. d. Separate origins in Africa and Australia with migrations from both these areas to displace all other populations. e. A strong influence of modern humans evolving first in Africa that left an imprint on populations throughout the world that is detectable today.

ANS: d REF: Approaches to Understanding Modern Human Origins 5. Researchers have recently sequenced the genetic identities of nine ancient fully modern H. sapiens from sites in Italy, France, the Czech Republic, and Russia by using genetic material that is transmitted between generations without recombination with male DNA. What is this material? a. The Y chromosome b. mtDNA c. The ABO blood groups d. The Y chromosome and the ABO blood groups e. Only cranial remains ANS: b REF: Approaches to Understanding Modern Human Origins 6. According to Partial Replacement Models, modern humans first appeared in Africa:

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a. b. c. d. e.

and interbred with premodern populations of Eurasia, thus partially displacing them. and remained there until modern humans from Asia displaced them. about 500,000 years ago. but were later displaced by European Neandertals. and migrated to Indonesia before arriving to Europe.

ANS: a REF: Approaches to Understanding Modern Human Origins 7. Two different Replacement Models have been proposed. They differ from each other with respect to which of the following? a. The anatomy of modern humans b. The timing of the origin of modern humans c. Whether a speciation event caused the demise of Neandertals d. The origin and dispersal of the first modern human populations e. The use of DNA sequences in analyses ANS: d REF: Approaches to Understanding Modern Human Origins 8. What does the Regional Continuity Model of modern Homo sapiens origins not propose? a. Modern humans did not appear solely in Africa. b. Premodern populations in Europe, Asia, and Africa all evolved into modern Homo sapiens. c. There was gene flow between premodern populations from different regions of the Old World. d. Local populations would have evolved totally independently from one another. e. Local populations would not have evolved totally independently from one another.

ANS: d REF: Approaches to Understanding Modern Human Origins 9. According to the Regional Continuity Model, ________ prevented local populations of premodern Homo sapiens from becoming separate species. a. founder’s effect b. gene flow c. displacement by African Homo sapiens d. mitochondrial DNA e. genetic drift ANS: b REF: Approaches to Understanding Modern Human Origins 10. Earliest modern human occupation dates to 50,000 in: a. Australia. b. South America. c. North America. d. Africa. e. Europe.

ANS: a REF: The Earliest Discoveries of Modern Humans

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11. Anatomically modern Homo sapiens fossils from Africa have been dated to about _____ years ago. a. 100,000-70,000 b. 200,000-100,000 c. 195,000-80,000 d. 35,000 e. 65,000 ANS: b REF: The Earliest Discoveries of Modern Humans 12. The Herto remains are: a. from South Africa. b. from the Middle Awash area of Ethiopia. c. considered to be modern Neandertal. d. considered to be Ardipithecus. e. the earliest European evidence of modern humans.

ANS: b REF: The Earliest Discoveries of Modern Humans 13. Current evidence indicates that the earliest anatomically modern Homo sapiens fossils are from which geographical location? a. Asia b. Europe c. North America d. Australia e. Africa ANS: e REF: The Earliest Discoveries of Modern Humans 14. Thus far, the earliest specimens of modern Homo sapiens are from which site? a. Omo Kibish b. Klasies River Mouth c. Qafzeh d. Cro-Magnon e. Kow Swamp ANS: a REF: The Earliest Discoveries of Modern Humans 15. The analysis of the Herto remains are significant for all of the following reasons except: a. it is most similar to Australopithecus. b. it has a cranial capacity near that of contemporary H. sapiens. c. it has well-controlled radiometric dates. d. it is specifically similar to modern H. sapiens. e. it indicates that modern humans first originated in Africa.

ANS: a REF: The Earliest Discoveries of Modern Humans

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16. Early modern Homo sapiens remains from the Near East include: a. Kow Swamp. b. Skhūl. c. Herto. d. Omo Kibish. e. Zhoukoudian.

ANS: b REF: The Earliest Discoveries of Modern Humans 17. The Skhūl site is dated to approximately ________ years ago. a. 250,000-200,000 b. 75,000-43,000 c. 200,000-100,000 d. 130,000-100,000 e. 40,000 ANS: d REF: The Earliest Discoveries of Modern Humans 18. Of the sites listed below, which is the most important for determining the morphology of the earliest Homo sapiens in Western Europe? a. Cro-Magnon b. Tabun c. Katanda d. Mladeč e. Herto ANS: a REF: The Earliest Discoveries of Modern Humans 19. Which of the following sites in Western Europe may offer evidence for genetic continuity between Neandertals and modern humans? a. Abrigo do Lagar Velho b. Tabun and Qafzeh c. Qafzeh and Skhūl d. Border Cave and Vindija e. Cro Magnon ANS: a REF: The Earliest Discoveries of Modern Humans 20. _______ is a site in southern France dated to 28,000 years ago. Fossil material from this site became the archetype for Upper Paleolithic Europeans. a. Skhūl b. La Chapelle-aux-Saints c. Cro-Magnon d. Qafzeh e. Zhoukoudian ANS: c

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REF: The Earliest Discoveries of Modern Humans 21. The question of whether modern humans and Neandertals interbred at some point: a. cannot be answered because there is no fossilized soft tissue available. b. was never an issue among paleoanthropologists. c. is far from settled and remains an unresolved debate based on dating errors. d. was called into question with the discoveries at Zhoukoudian. e. is established based on genetic evidence.

ANS: e REF: The Earliest Discoveries of Modern Humans 22. The Abrigo do Lagar Velho specimen is an important discovery that aids in the understanding of possible interbreeding between Neandertals and anatomically modern H. sapiens because the remains are: a. from Spain. b. dated to about 50,500 years ago. c. a highly mixed set of anatomical features. d. located along a significant migration route from Africa to Europe. e. an incomplete skeleton of an adult female.

ANS: c REF: The Earliest Discoveries of Modern Humans 23. Archaeological sites in Australia have been dated to __________ years ago. a. 25,000 b. 30,000 c. 75,000 d. 55,000 e. 100,000 ANS: d REF: The Earliest Discoveries of Modern Humans 24. A newly published controversial date for the Lake Mungo remains indicates they may be as old as ________ years. a. 30,000 b. 400,000 c. 10,000 d. 600,000 e. 150,000, or the earliest specimens from Africa ANS: a REF: The Earliest Discoveries of Modern Humans 25. The Kow Swamp remains: a. are more robust than the Lake Mungo remains. b. are dated earlier than Lake Mungo remains. c. are from Central Europe. d. were dated from museum collections and therefore dates may be invalid.

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e. suggest that native Australians are later migrants from elsewhere, not descendants of a single migration dating back to about 50,000 ya.

ANS: a REF: The Earliest Discoveries of Modern Humans 26. The skeletal remains of Homo floresiensis are notable for each of the following characteristics or assumptions except: a. the short stature. b. the small cranial capacity. c. they were living 13,000 years ago. d. their predecessors were likely H. erectus populations. e. they came to Flores on rafts, the remains of which were recovered from the island of Flores.

ANS: e REF: Something New and Different: The “Little People” 27. The Upper Paleolithic: a. began at the onset of the Pleistocene. b. is a cultural period attributed primarily to Neandertals. c. is characterized by the invention of iron tools. d. began about 150,000 years ago. e. is divided into five different industries, based on stone tool technologies.

ANS: e REF: Technology and Art in the Upper Paleolithic 28. The Upper Paleolithic culture period is divided into categories based on stone tool technologies.

These include all of the following except: a. Solutrean. b. Magdalenian. c. Aurignacian. d. Chatelperronian. e. Grottevian.

ANS: e REF: Technology and Art in the Upper Paleolithic 29. The Upper Paleolithic culture period began in Western Europe about ________ years ago. a. 40,000 b. 10,000 c. 5,000 d. 70,000 e. 100,000 ANS: a REF: Technology and Art in the Upper Paleolithic 30. During the last glaciation in Eurasia: a. human habitation was impossible. b. the entire area was permanently covered with ice-sheets.

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c. a warming trend at about 30,000 ya partially melted the glacial ice. d. hunting was impossible because there were no animals in the region. e. Neandertals became extinct.

ANS: c REF: Technology and Art in the Upper Paleolithic 31. What is the benefit of an atlatl? a. It is a unique type of projectile point. b. It is used for starting fires. c. It is used to increase the force and distance of a spear throw. d. It can be used as a drill. e. It is used for fishing.

ANS: c REF: Technology and Art in the Upper Paleolithic 32. Types of Upper Paleolithic art include all of the following except: a. engravings. b. cave paintings. c. sculptured figurines. d. fired ceramics. e. rock art.

ANS: d REF: Technology and Art in the Upper Paleolithic 33. Lascaux and Altamira: a. are well known Neandertal sites. b. are 20,000 year-old campsites. c. contain evidence of butchered mammoths. d. are famous for their numerous cave bear skulls. e. are famous for their elaborate cave paintings.

ANS: e REF: Technology and Art in the Upper Paleolithic 34. The cave paintings in the Grotte Chauvet: a. are relatively crude and primitive. b. mostly depict landscapes. c. mostly depict female humans. d. date to about 10,000 ya. e. date to 35,000 ya.

ANS: e REF: Technology and Art in the Upper Paleolithic 35. Early rock art from Africa may be as old as ________ years. a. 10,000 b. 68,000 c. 100,000

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d. 28,000 e. 40,000 ANS: d REF: Technology and Art in the Upper Paleolithic

True/False Questions 1. The transition between premodern and anatomically modern forms of humans may have occurred as early as 500,000 years ago in Africa.

ANS: False REF: Introduction 2. The first modern Homo sapiens evolved from Western Europe.

ANS: False REF: Approaches to Understanding Modern Human Origins 3. The Partial Replacement Models have been bolstered by the sequencing of Neandertal genome.

ANS: True REF: Approaches to Understanding Modern Human Origins 4. Recent analyses have shown that the mtDNA from fossil modern human skeletons is somewhat limited because mtDNA is a fairly small segment of DNA, and is transmitted between generations as a single unit.

ANS: True REF: Approaches to Understanding Modern Human Origins 5. As a group, the specimens from Skhūl all have modern human features and none show any hints of premodern features.

ANS: False REF: Approaches to Understanding Modern Human Origins 6. It is hypothesized that some population of inhabitants from Indonesia was the first group to colonize Australia.

ANS: True REF: The Earliest Discoveries of Modern Human 7. Abrigo do Lagar Velho is an important Upper Paleolithic site located in the Near East.

ANS: False REF: The Earliest Discoveries of Modern Human 8. There is evidence of chronological overlap in occupation of the Near East by Neandertals and modern humans.

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ANS: True REF: The Earliest Discoveries of Modern Human 9. Genetic evidence indicates that all native Australians are descendants of a single migration 50,000 ya.

ANS: True REF: The Earliest Discoveries of Modern Human 10. The morphology of the child’s skeleton from Abrigo do Lagar Velho in Portugal has been cited as support for the regional continuity model for understanding modern human origins.

ANS: False REF: The Earliest Discoveries of Modern Human 11. The Upper Paleolithic was a period during which there were rapid shifts in climatic conditions.

ANS: True REF: Technology and Art in the Upper Paleolithic 12. The bow and arrow seems to have first appeared during the Magdalenian.

ANS: True REF: Technology and Art in the Upper Paleolithic 13. Bone tools, beads, and decorated ocher fragments were found at Blombos Cave as old as 73,000 years old.

ANS: True REF: Technology and Art in the Upper Paleolithic 14. By 165,000 ya individuals were using fire at Pinnacle Point, as evidenced by microliths that show evidence that the stone had been carefully heated.

ANS: True REF: Technology and Art in the Upper Paleolithic

Short Answer Questions 1. Summarize the main points of the various Models of Human Origin.

ANS: There are two primary models: the Regional Continuity Model: Multiregional Evolution argues that local populations continued simultaneous development over time to form anatomically modern humans. The Replacement Models are two different types: the complete replacement argues that about 200,000 years ago modern human emerged in Africa and migrated out to replace all other human populations extant. The partial replacement model argues that modern humans emerged in Africa and migrated outward to interbreed with Neandertal between 80,000 and 50,000 ya.

REF: Approaches to Understanding Modern Human Origins 2. Define the problematic nature of the genetic evidence regarding the origins of modern Homo sapiens.

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ANS: There is evidence of interbreeding, but it is not consistent in percentage. Also, we still have relatively limited genetic evidence across geographical regions.

REF: Approaches to Understanding Modern Human Origins 3. Summarize the importance of the discovery of the child’s skeleton from the Abrigo do Lagar Velho relative to the debate on modern human origins.

ANS: This skeleton provides the best evidence of interbreeding between Neandertals and modern H. sapiens. It provides excellent support for the partial replacement model.

REF: The Earliest Discoveries of Modern Human 4. Present the evidence relative to the human occupation of Australia.

ANS: There is some controversy, but genetic evidence points to a single migration dating back to 50,000 ya.

REF: The Earliest Discoveries of Modern Human 5. What does the discovery of Homo floresiensis tell us about the adaptive potential of humans?

ANS: This may be a case of insular dwarfism caused by adaptation to reduced resources.

REF: Something New and Different: The “Little People” 6. Why are the Upper Paleolithic cave paintings significant to the understanding of the Upper Paleolithic?

ANS: They tell us about the innovative capabilities of our species and they demonstrate symbolism, technology, and art as aesthetic. They are cultural products.

REF: Technology and Art in the Upper Paleolithic 7. Describe the remains found in African sites that indicate accomplishments in Upper Paleolithic art and technology.

ANS: These include various things such as rock art (Apollo 11), bone tools, beads and ocher fragments (Blombos), microliths and shellfish exploitation (Pinnacle Point), hafted tools, snares and traps (Sibudu), notched bones, wooden digging sticks bone awls and points (Border Cave), and bonework (Katanda).

REF: Technology and Art in the Upper Paleolithic 8. Why do most paleoanthropologists agree that several fossil forms, dating back to 100,000 ya, should be included in as fully modern humans?

ANS: The primary argument is because they were like us skeletally, genetically, and behaviorally.

REF: Introduction

Essay Questions 1. Discuss the two main hypotheses that have been used to explain the origin and dispersal of modern humans.

ANS: Will vary REF: Approaches to Understanding Modern Human Origins

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2. Discuss the evidence that suggests modest interbreeding took place between Neandertals and modern humans.

ANS: Will vary REF: The Earliest Discoveries of Modern Humans 3. What were the environmental and climatic conditions from 40,000 ya to 10,000 ya in Eurasia? How did these factors influence the technological and cultural innovations of Upper Paleolithic humans?

ANS: Will vary REF: Technology and Art in the Upper Paleolithic 4. Discuss the Upper Paleolithic cultural period, including innovations in technology, art and burials.

ANS: Will vary REF: Technology and Art in the Upper Paleolithic

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CHAPTER 12: HUMAN VARIATION AND ADAPTATION Chapter Outline I.

Introduction A. Notions about human diversity still influence political and social perceptions.

1. Techniques have been developed to allow scientists to directly examine the DNA molecules; this research reveals differences among people at the level of single nucleotides.

II. Historical Views of Human Variation A. Because differences in skin color were apparent when different human groups came into contact, skin color became one of the most common traits used in racial classification. As early as 1350 BC Egyptians had classified humans based on skin color.

B. Johann Friedrich Blumenbach (1752-1840) classified humans into five races.

1. He used skin color (white, yellow, brown, red and black) as well as other traits, but emphasized that humans do not fall neatly into these categories.

C. To many Europeans, non-Christian populations from other parts of the world were seen as “uncivilized” and they applied the concept of biological determinism where there is an association between physical characteristics and intelligence, morals, values, abilities, and social and economic status.

D. After 1850, biological determinism, the belief in a biologically inherited association between physical characteristics and behavioral attributes, became a dominant theme in the European and American schools of racial classification.

1. Notable figures in Europe and the United States subscribed to biological determinism, including Thomas Jefferson, Georges Cuvier, Benjamin Franklin, Charles Lyell, Abraham Lincoln, Charles Darwin, and Oliver Wendell Holmes.

2. Charles Darwin’s cousin, Francis Galton, wrote and lectured on eugenics, the theme of race improvement through selective breeding. The eugenics movement became very popular in America throughout the 1930s, and the eugenics movement in Germany formed the basis of Nazi ideas of racial purity.

III. The Concept of Race A. Humans are all members of the same polytypic species, Homo sapiens.

B. Within local populations, there is a great deal of genotypic and phenotypic variation between individuals.

1. Geographically-localized peoples possessing particular combinations of skin color, face form, and nose form, etc. have been lumped together in categories called races. a. Race has been used synonymously with species. b. The term “race” is not well defined. Since the 1960s, race has referred to culturally- as well as biologically-defined groups of people. (i) References to national origin in the guise of ethnicity have become increasingly popular lately, and this term is incorrectly equated with the more emotionally charged term of race. (a) In biological usage, race refers to geographically-patterned phenotypic variation within a species. The modern emphasis uses the tools of population genetics to discover the adaptive significance of human phenotypic and genotypic variation.

C. Broadly-defined racial categories have little biological reality because the genetic variation within groups is vastly greater than the genetic variation between groups.

1. Biologists more typically refer to populations, or subspecies.

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2. Concepts of race are no longer valid, because the amount of genetic variation accounted for by differences between groups is exceeded by the variation that exists within groups.

3. Forensic anthropologists concentrate on phenotypic variables because they are called on by law enforcement agencies to identify sex, age, stature, and ancestry (racial background) from skeletal remains. a. They are able to establish broad population affinities with about 80 percent accuracy.

4. Other physical anthropologists argue that race is a meaningless cultural construct that has no basis in biology.

D. It is clear that traditional racial traits have a continuous range of phenotypic variation and it is impossible to construct discrete phenotypic or genotypic boundaries around populations. Humans are not inherently typological in nature.

1. It is the job of the anthropologist to inform the general public of accurate information regarding the causes of human variation.

2. Characteristics that have traditionally been used to define race are polygenic.

IV. Contemporary Interpretations of Human Variation A. Since the physical characteristics used to define race are polygenic, it is not possible to measure genetic influences.

B. Genomic studies enable scientist to sequence DNA, identify entire genes, and make comparisons between individuals and populations.

C. Human Polymorphisms 1. Contemporary studies of human variation focus on polymorphisms, characteristics that have different phenotypic expressions (the genetic locus governing the trait has two or more alleles). a. Populations often differ with respect to their allele frequencies for polymorphic traits and this requires evolutionary explanations.

2. The ABO system is of anthropological interest because its three alleles vary among human populations and their frequencies follow a clinal distribution. a. The A or B alleles rarely reach frequencies of 50 percent in human populations. b. South American Indian populations have frequencies of O that approach 100 percent. (i) High frequencies of O are also found in northern Australians. (ii) These unusually high frequencies may be the product of genetic drift.

3. Analyzing single traits can lead to confusions regarding population relationships, so studies of several traits simultaneously have become more commonplace.

D. Polymorphisms at the DNA Level 1. There are variations in DNA in the human genome; copy number variants are segments that vary from person to person, allowing for DNA fingerprinting of each person.

2. The most recent and comprehensive population data regarding worldwide patterns of variation come from analyses of extremely large portions of DNA, called “whole genome” analysis.

3. New studies have revealed the influence and frequency of non-protein-coding portions of DNA – these are referred to as single nucleotide polymorphisms.

4. The results of new studies confirm earlier findings and provide new insights: a. Confirm higher degree of genetic variation in African populations as compared to any other geographic group. b. Confirm genetic relationships between populations worldwide and the nature of human migrations out of Africa. c. Suggest patterning of human variation at the global level that may help identify genetic risk factors influencing how susceptible different populations are to various diseases.

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V. Human Biocultural Evolution A. Because humans live in a cultural environment, human evolution is only understandable within this context.

B. For example, before humans developed agriculture, they rarely lived near mosquito breeding areas.

C. With the advent of slash-and-burn agriculture some 2,000 ya, prime mosquito breeding areas were created near human living areas.

1. Following WWII, DDT spraying was initiated to control mosquito populations. Both mosquito populations and the frequency of the HbS allele declined initially, but natural selection eventually resulted in DDT-resistant strains of mosquitoes. This caused a rise in the frequency of malaria.

D. Lactose intolerance (the reduced production of the enzyme lactase) is an example of human biocultural evolution as a selective advantage for some human populations.

1. Most adult humans are lactose intolerant. However, European groups who share partial descent from Middle Eastern populations and some African groups, have high rates of lactose tolerance due to lactase persistence. b. These groups have a recent history of pastoralism. It is likely that their cultural dependence on milk products has increased the frequency of lactose tolerant individuals through natural selection.

VI. Population Genetics A. Used to interpret microevolutionary patterns.

B. A population is a group of interbreeding individuals who share a common gene pool.

C. Mate choice is conditioned by geographical, ecological, and social factors.

1. Breeding isolates are populations who tend to mate with individuals in their immediate vicinity.

2. Most humans today aren’t so clearly defined as members of particular populations as they would be if they belonged to breeding isolates.

D. To determine whether evolution is taking place at a given locus, population geneticists measure allele frequencies for specific traits and compare these with a set predicted by a mathematical formula: 1. The Hardy-Weinberg equilibrium is a hypothetical state that describes a population that is not evolving. Changes in allele frequencies result.

VII. The Adaptive Significance of Human Variation A. Adaptation includes environment and culture: 1. Examples in humans are physiological responses to stress, by maintaining homeostasis.

2. Physiological responses to environmental change are influenced by genetics.

B. Acclimatization is a physiological response to a change in environmental conditions.

1. Examples of acclimatization include tanning in response to exposure to ultraviolet radiation and increased hemoglobin production on exposure to hypoxia.

2. Developmental acclimatization results from exposure to a changing environment during growth.

C. Solar Radiation and Skin Color 1. The relationship between solar radiation, vitamin D, and skin color is an example of adaptation and natural selection. a. Skin color in native populations follows a particular geographic pattern: the darkest skin is found in populations living in the tropics, and lighter skin tones are found in more northern latitudes. b. Skin color is primarily influenced by the pigment melanin, which is produced in the epidermis by melanocytes. Although all humans possess about the same number of

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melanocytes, human populations differ with respect to the amount and size of the melanin granules produced by the melanocytes. (i) Because melanin absorbs ultraviolet (UV) radiation, it provides protection against the damaging effects of ultraviolet radiation such as skin cancer.

2. Darker Skin: Natural selection has favored dark skin near the equator because of the high levels of UV radiation there: a. An additional benefit of darkly-pigmented skin is that it prevents degradation of folate, an important B vitamin, by UV radiation. b. An alternate hypothesis focuses on the role of folate (a B vitamin) in preventing neural tube defects during embryonic development, such as spina bifida. UV radiation depletes folate levels in light-skinned individuals; therefore, darker skin would be adaptive in higher UV environments.

3. Lighter skin: Natural selection may have acted rapidly against darker skin as humans moved to northern latitudes: a. Heavily-pigmented skin would have been adaptive to early hominins living in Africa, but as hominins migrated out of Africa the environmental factors changed. Hominins living in northern Eurasia encountered lower levels of UV radiation, and the selective pressure for heavily-pigmented skin was relaxed. b. The need for vitamin D production in the skin (through the interaction of UV radiation and a cholesterol-like compound in skin cells) to protect individuals from the deleterious effects of rickets was probably the most significant selective force for depigmentation.

D. The Thermal Environment Homo sapiens populations face ranges from very hot (above 120°F) to very cold (below -60°F): 1. Responses to heat are more effective than our physiological responses to cold, reflecting our tropical ancestry. a. All human populations are effective at dissipating heat through evaporative cooling, since all humans have about 1.6 million sweat glands, resulting in the ability to sweat up to 3 liters of water per hour while engaged in heavy work in high heat. b. Vasodilation, the widening of the capillaries near the surface of the skin to permit increased blood flow, is another mechanism for radiating body heat.

2. Human populations vary in body size and proportions in general accordance with Bergmann’s and Allen’s rules, both of which describe the relationship between mass-tosurface ratios and heat retention and loss. a. Bergmann’s rule concerns the relationship of body mass or volume to surface area. b. Allen’s rule concerns the shape of the body, especially appendages. c. The optimal body shape in hot climates is linear with long arms and legs, whereas the most suitable body type for cold climates is stocky with shorter limbs.

3. Responses to cold include heat retention and heat production. a. Increased metabolic rate, shivering, and vasoconstriction to shunt blood to the body core are all short-term responses to cold. (i) Populations exposed to chronic cold maintain higher metabolic rates than populations living in warmer climates. (ii) Long-term responses to cold include prolonged vasoconstriction when there is no threat of frostbite, and intermittent vasoconstriction and vasodilation when frostbite is a threat.

E. High Altitude populations (25 million people live at altitudes of 10,000 feet or more) are subjected to multiple stressors, including hypoxia, more intense solar radiation, cold, low humidity, wind, and a reduced nutritional base.

1. Responses to hypoxia include increased respiration rate, heart rate, and production of red blood cells.

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2. High altitude natives exhibit developmental acclimatization in the form of slowed growth and maturation, a larger chest size, a larger heart, and more efficient oxygen diffusion to the tissues of the body. Does not affect reproduction. a. There is some evidence that Tibetans and Quechuans have genetically adapted to high altitudes.

VIII. Infectious Diseases have exerted selective pressure on human populations, influencing the frequency of alleles involved in the functioning of the immune system.

A. Cultural factors have played an important role in the spread of diseases, because up until 10,00012,000 ya, all humans lived in small nomadic hunting and gathering groups. They rarely stayed in one location for long, and had minimal contact with refuse heaps that house vectors. As humans came to live in large settled communities, their living conditions increasingly favored the transmission of diseases.

1. For a disease to become endemic in a population, there must be enough people to sustain it.

2. Exposure to domestic animals provided an opportune environment for the spread of several zoonotic diseases, e.g. tuberculosis and influenza.

3. AIDS with its possible relationship to the allele that blocks an important receptor site on T4 and other immune cells, and smallpox with its relationship to higher rates of infection in blood type A and AB individuals, are all examples of the selective role of infectious diseases in human populations.

4. The best known epidemic in history was the Black Death (bubonic plague) in the midfourteenth century.

B. The Continuing Impact of Infectious Disease as a selective force in contemporary human populations cannot be denied.

1. The past few years has seen the reemergence of many bacterial diseases, such as influenza, pneumonia, tuberculosis, and cholera. These diseases are resistant to antibiotics because indiscriminant use of antibiotics has selected for antibiotic-resistant strains of bacterial diseases.

2. HIV is the best example of a disease-causing organism in evolution and adaptation.

3. Influenza is a zoonotic, contagious respiratory disease that has probably killed more humans than any other infectious disease. Health officials are on the watch for an influenza pandemic.

4. Tuberculosis is currently listed as the world’s leading killer of adults by the WHO (World Health Organization).

C. Fundamental to all factors of infectious disease is human population size, which contributes to environmental disturbance and further global warming.

Key Terms and Concepts Acclimatization, p. 322 Biological determinism, p. 312 Breeding isolates, p. 321 Endemic, p. 332 Eugenics, p. 313 Evaporative cooling, p. 327 Gene pool, p. 321 Hardy-Weinberg equilibrium, p. 321 Homeostasis, p. 322 Hypoxia, p. 330 Lactase persistence, p. 319 Neural tube, p. 325

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Pandemic, p. 335 Polymorphisms, p. 317 Polytypic, p. 313 Population genetics, p. 321 Slash-and-burn agriculture, p. 318 Spina bifida, p. 325 Stress, p. 322 Vasoconstriction, p. 329 Vasodilation, p. 328 Vectors, p. 332 Zoonotic, p. 332

Lecture Suggestions 1. Expand on the historical views and attitudes regarding human phenotypic variation. Trace the rise of the eugenics in America and Europe.

2. Emphasize the importance of understanding how humans and pathogens exert selective pressures on each other, creating a dynamic relationship between disease organisms and their hosts. Visit the website http://ehp.niehs.nih.gov/1104650/ to see new research on the effect of antibiotic pollution on bacteria “of health.”

3. Discuss information about human diversity available to scholars like Charles Darwin and how this information differs from what we know today. View Nina Jablonski as she discusses the value of using NASA satellite imagery to understanding that differing skin colors are simply our bodies' adaptation to varied climates and levels of UV exposure. http://www.ted.com/talks/lang/en/nina_jablonski_breaks_the_illusion_of_skin_color.html 4. Distinguish how culture affects human evolution (sickle-cell anemia); how humans have been evolving and continue to evolve, not just in spite of culture, but because of culture (lactose tolerance); and how culture has actually increased the rate of human evolution (invention and spread of agriculture, or increasing population density and urbanization.)

Internet Exercises 1. Go online to the American Association of Physical Anthropology website http://www.physanth.org and choose the “Position statements” link http://physanth.org/association/positionstatements/biological-aspects-of-race. Briefly outline the main points of the position on the biological aspects of race.

2. Go online and search for “clinal variation.” How many examples of the clinal distribution of genotypes and/or phenotypes can you find? The Palomar site has some models to consider at http://anthro.palomar.edu/vary/vary_2.htm.

3. Visit the American Anthropology website for interesting articles, videos, and other resources to use during the classroom in order to explore the complexity of race, as a biological fallacy, but social reality. www.understandingrace.org.

4. One very interesting challenge in human variation is race-based medicine. See the TED talk on this at: https://www.ted.com/talks/dorothy_roberts_the_problem_with_race_based_medicine.

Multiple Choice Questions 1. Categorizing people on the basis of skin color: a. is mostly a twentieth century phenomenon. b. has been practiced only by Western Europeans. c. is a valid approach to racial taxonomy. d. has a long history and has been practiced by many peoples.

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e. began with Christopher Columbus.

ANS: d REF: Historical Views of Human Variation 2. As early as 1350 BC, ancient Egyptians classified humans based on: a. intelligence. b. height. c. eye color. d. cranial shape. e. skin color.

ANS: e REF: Historical Views of Human Variation 3. What is the false belief that there is a relationship between physical traits and certain behavioral traits such as intelligence and morality? a. Eugenics b. Monogenism c. Polygenism d. Biological determinism e. Homeostasis ANS: d REF: Historical Views of Human Variation 4. What is the term for the philosophy of “race improvement” through the forced sterilization of some groups and the encouraged reproduction of others? a. Eugenics b. Genetics c. Monogenism d. Polygenism e. Polytypic ANS: a REF: Historical Views of Human Variation 5. Who was responsible for popularizing eugenics among 19th century Europeans? a. Charles Darwin b. Francis Galton c. Georges Cuvier d. Charles Lyell e. Thomas Jefferson ANS: b REF: Historical Views of Human Variation 6. The eugenics movement: a. formed the basis for notions of racial equality in Nazi Germany. b. was popular throughout the 1970s. c. is a now discredited view of racial purity.

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d. was begun by Charles Darwin. e. is supported by biological data.

ANS: c REF: Historical Views of Human Variation 7. A polytypic species: a. is one that has no phenotypic variability. b. has never been observed in nature. c. is one composed of local populations that differ from one another with regard to the expression of no more than three traits. d. is one composed of local populations that differ from one another with regard to the expression of one or more traits. e. is composed of widely dispersed populations.

ANS: d REF: The Concept of Race 8. The application of evolutionary principles to the study of human variation: a. reinforced traditional views of races as fixed biological entities that do not change. b. allowed scientists to ignore the adaptive significance of most traits. c. helped replace earlier views based solely on observed phenotypes. d. allowed scientists to divide the human species precisely into well-defined races. e. has been of little value for understanding human variation.

ANS: c REF: The Concept of Race 9. In its most common biological usage, the term race: a. has precise definitions agreed upon all anthropologists. b. refers to the geographically-patterned phenotypic variation within a species. c. refers only to skin color. d. refers only to IQ. e. refers to a person’s nationality.

ANS: b REF: The Concept of Race 10. The evolutionary development of the species H. sapiens: a. is determined solely by genetic factors. b. is determined solely by environmental factors. c. can be accurately measured by IQ tests. d. is solely a Mendelian trait. e. is the result of both genetic and environmental factors.

ANS: e REF: Human Biocultural Evolution 11. The ABO system is interesting from an anthropological perspective because it: a. illustrates that allele frequencies do not vary among populations. b. illustrates that some allele frequencies do vary among populations.

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c. demonstrates that natural selection does not alter allele frequencies. d. has never been convincingly demonstrated for any allele. e. is no longer present in human populations.

ANS: b REF: Contemporary Interpretations of Human Variation 12. The frequency of the O allele is almost 100 percent in indigenous: a. Northern Europeans. b. Chinese. c. Eurasians. d. Africans. e. South Americans.

ANS: e REF: Contemporary Interpretations of Human Variation 13. What is significant about areas in the DNA that contain repeated segments? a. They are always used in biological determinism. b. They are the basis for DNA fingerprinting. c. They are the same from person to person. d. They cannot be mapped. e. They disprove the belief that there are variations of the human genome.

ANS: b REF: Contemporary Interpretations of Human Variation 14. Lactose intolerance can be characterized by all of the following except: a. results from the lack of lactase. b. has a genetic basis. c. is a good example of biocultural evolution. d. can be influenced by the environment. e. does not involve a person’s ability to digest milk.

ANS: e REF: Human Biocultural Evolution 15. The total complement of genes shared by the reproductive members of a population is called a(n): a. nuclear matrix. b. species isolate. c. breeding population. d. gene pool. e. gene line.

ANS: d REF: Population Genetics 16. Population geneticists use the Hardy-Weinberg equilibrium equation to determine: a. whether evolution is occurring at all loci throughout the genome simultaneously. b. whether allele frequencies in a population are changing. c. the mode of inheritance of Mendelian traits.

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d. whether a particular trait is polygenic. e. if human populations are operating on evolutionary forces.

ANS: b REF: Population Genetics 17. Biological systems are balanced systems maintained by the interaction of physiological mechanisms that compensate for both external and internal changes. Such a balanced system is called: a. hypoxia. b. homeostasis. c. heterostasis. d. acclimatization. e. polystasis.

ANS: b REF: The Adaptive Significance of Human Variation 18. Acclimatization refers to which of the following? a. Long-term adaptations of species to certain environmental conditions b. An individual’s short-term physiological responses to the environment c. The appearance of a new species d. Slow genetic changes in populations e. Changes in climate ANS: b REF: The Adaptive Significance of Human Variation 19. Adaptations are: a. seen only in nonhuman animals. b. the same as acclimatization responses. c. always temporary. d. long-term evolutionary changes. e. short-term evolutionary changes.

ANS: d REF: The Adaptive Significance of Human Variation 20. Which of the following contributes most to skin color? a. Hemoglobin b. Melanin c. Carotene d. Vitamin D e. Short-term acclimatization ANS: b REF: The Adaptive Significance of Human Variation 21. Which of the following protects from ultraviolet radiation? a. Carotene b. Hemoglobin

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c. Vitamin D d. Melanin e. Melanocytes ANS: d REF: The Adaptive Significance of Human Variation 22. Melanocytes: a. are cells that produce carotene. b. are found in the dermis. c. only occur in dark-skinned individuals. d. produce melanin. e. cause cancer.

ANS: d REF: The Adaptive Significance of Human Variation 23. Dark skin is found in populations near the equator. Why? a. It protects from frostbite. b. It increases the chance of heat evaporation. c. It helps prevent rickets. d. It protects from the damaging effects of UV radiation on folate. e. It increases the skin’s exposure to ultraviolet radiation.

ANS: d REF: The Adaptive Significance of Human Variation 24. Ultraviolet radiation can be an important factor in selection for increased melanin production because UV radiation can cause which of the following? a. Rickets b. Albinism c. Skin cancer d. The rebuilding of folate e. Spina bifida ANS: c REF: The Adaptive Significance of Human Variation 25. What causes rickets? a. Overexposure to ultraviolet radiation b. Too much vitamin D c. An insufficient amount of melanin d. Too few melanocytes e. An insufficient amount of vitamin D ANS: e REF: The Adaptive Significance of Human Variation 26. Studies have shown that UV radiation rapidly depletes ______, which plays a crucial role in neural tube development of the embryo. a. melanin

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b. c. d. e.

melanocytes carotene folate vitamin C

ANS: d REF: The Adaptive Significance of Human Variation 27. Sweating: a. is a uniquely mammal response to heat. b. has no detrimental physiological effects. c. is not an effective means of dissipating heat. d. permits cooling through evaporation. e. is an ability that varies from one human population to another.

ANS: d REF: The Adaptive Significance of Human Variation 28. Response mechanisms for regulating body heat include all of the following except: a. increased production of red blood cells. b. vasodilation. c. vasoconstriction. d. evaporative cooling. e. increased blood flow to the skin.

ANS: a REF: The Adaptive Significance of Human Variation 29. Bergmann’s rule: a. states that a linear body with long arms and legs is optimal for cold climates. b. concerns the relationship between climate and shape and size of appendages. c. states that bodies with increased mass or volume to surface area are optimal for cold climates. d. is based upon the principle that as arms increase in length, there is a corresponding increase in surface area. e. is based on the principle that heat is retained at the body surface.

ANS: c REF: The Adaptive Significance of Human Variation 30. Hypoxia: a. is the reduced availability of oxygen. b. occurs at higher altitudes because the atmosphere contains less oxygen than at sea level. c. is a form of racial-based eugenics. d. is a problem for people living at sea level during certain seasonal periods. e. is more common among light-skinned people than dark-skinned people.

ANS: a REF: The Adaptive Significance of Human Variation 31. Developmental acclimatization occurs in those individuals who: a. have recently moved to a high altitude environment.

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b. c. d. e.

have spent their adult life at high altitude. were born in a high altitude environment, but who grew up in a low altitude environment. grow up in high altitude environments. live at high altitude and are lactose intolerant.

ANS: d REF: The Adaptive Significance of Human Variation 32. Agents that carry disease from one carrier to another are called: a. pathogens. b. vectors. c. pandemics. d. endemics. e. antigens.

ANS: b REF: Infectious Disease 33. What is AIDS caused by? a. Mosquito bites b. A bacterium c. A mutation on a cell’s receptor site d. A virus e. Bad meat ANS: d REF: Infectious Disease 34. When a disease is continuously present in a population it is said to be: a. pandemic. b. chronic. c. epidemic. d. lethal. e. endemic.

ANS: e REF: Infectious Disease 35. What is an extensive outbreak of disease affecting large numbers of people over a wide area called? a. Pandemic b. Epidemic c. Vector d. Endemic e. Pathogen ANS: a REF: Infectious Disease 36. The World Health Organization lists ______ as the world’s leading killer of adults. a. car crashes

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b. c. d. e.

smallpox tuberculosis cholera AIDS

ANS: c REF: Infectious Disease

True/False Questions 1. Anders Retzius was the first European scientist to classify humans into races.

ANS: False REF: Historical Views of Human Variation 2. Francis Galton, Darwin’s cousin, originated the eugenics approach to “race improvement.”

ANS: True REF: Historical Views of Human Variation 3. The term race currently has only biological connotations and is without any social significance.

ANS: False REF: The Concept of Race 4. The term ethnicity was originally proposed in order to avoid the emotional baggage associated with the term race.

ANS: True REF: The Concept of Race 5. Forensic anthropologists must deal with the race concept because they are asked by law enforcement agencies to identify an individual’s race from skeletal remains.

ANS: True REF: The Concept of Race 6. The majority of modern anthropologists regard biological determinism as a valid mode of explaining human racial differences.

ANS: False REF: Historical Views of Human Variation 7. The most interesting fact about human skin color is that there appears to be no adaptive significance whatsoever to population-level variations in skin color.

ANS: False REF: The Adaptive Significance of Human Variation 8. Developmental acclimatization occurs in high-altitude natives during growth and development.

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ANS: True REF: The Adaptive Significance of Human Variation 9. Thanks to the modern medicine, many infectious diseases such as tuberculosis and cholera are no longer a threat to human populations.

ANS: False REF: Infectious Disease 10. Infectious diseases have exerted enormous selective pressures on our species.

ANS: True REF: Infectious Disease

Short Answer Questions 1. What is eugenics and what role has it played in human history?

ANS: It is the philosophy of “race improvement” through the forced sterilization of members of some groups and increased reproduction among others. It played a role in the false ideas of race purity expressed ion Nazi Germany.

REF: Historical Views of Human Variation 2. What does it mean when one states that humans are members of the same polytypic species?

ANS: It refers to the fact that humans are divided into populations that differ in the expression of one or more traits.

REF: The Concept of Race 3. What does it mean to say that the ABO blood system is polymorphic?

ANS: It means that at the locus of the trait there are two or more alleles. The ABO blood system has three possible alleles.

REF: Contemporary Interpretations of Human Variation 4. What is the physiological mechanism of lactose intolerance? Why is the ability to digest milk sugars an example of biocultural evolution?

ANS: Lactose intolerance is caused by a discontinued production of lactase in adults. The ability to digest milk sugars is tied directly to coevolution, as those descended from dairying populations have retained their ability to digest milk sugar through lactase persistence.

REF: Human Biocultural Evolution 5. What is population genetics?

ANS: It is the study of the frequency of alleles, genotypes, and phenotypes in populations from a microevolutionary perspective.

REF: Population Genetics 6. Define vasoconstriction and describe its role in the human physiological response to cold.

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ANS: Vasoconstriction is narrowing of the blood vessels to reduce blood flow to the skin. Under extreme cold, this allows the body to restrict heat loss and conserve energy.

REF: The Adaptive Significance of Human Variation 7. What is hypoxia? What does it do to the body?

ANS: It is insufficient levels of oxygen in body tissues; oxygen deficiency. It creates physiological stress on heart, lungs, and brain.

REF: The Adaptive Significance of Human Variation 8. Explain what HIV is and the hypothesis of its origin. Describe why it is seen as the best example of evolution and adaptation in a pathogen.

ANS: It is the best documented study of evolution and adaptation of a pathogen. It is also the most mutable and genetically variable virus known. Scientists believe that HIV is a mutation from a chimpanzee virus known as SIV (simian immunodeficiency virus).

REF: Infectious Disease

Essay Questions 1. Define the term race. How does the modern use of race differ from the 19th century use of race?

ANS: Will vary REF: Historical Views of Human Variation 2. What is the adaptive value of dark skin tones in equatorial regions such as Africa? If all humans are ultimately from Africa, what hypotheses might explain why skin tones lightened as humans came to occupy more northern latitudes?

ANS: Will vary REF: The Adaptive Significance of Human Variation 3. Outline the general principles of Bergmann’s and Allen’s rules. Can we use these rules to explain human phenotypic variation at the level of the population?

ANS: Will vary REF: The Adaptive Significance of Human Variation 4. How did the adoption of a settled lifestyle affect patterns of infectious disease in human populations?

ANS: Will vary REF: Infectious Disease 5. Discuss the factors that are contributing to the reemergence of infectious diseases that used to be close to extinction.

ANS: Will vary REF: Infectious Disease

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CHAPTER 13: LEGACIES OF HUMAN EVOLUTIONARY HISTORY: EFFECTS ON THE LIFE COURSE Chapter Outline I.

Introduction A. Modern human beings are a highly-generalized and behaviorally-flexible species: 1. The human environment has changed more radically in the last few decades than at any point in the course of human evolutionary history.

2. The legacies of human evolution continue to have profound impacts on our biology and behavior.

II. Evolved Biology and Contemporary Lifestyles – Is there a Mismatch?

A. A mismatch or discordance exists that suggests our modern lives are in some ways disconnected from our evolved biology, with occasional harmful consequences.

B. Aspects of our ancestral ways of life would probably result in improved health if adopted (e.g. exercise, dietary changes); returning to those lifestyles is highly unlikely.

III. Biocultural Evolution and the Life Course A. Cultural factors interact with genetically-based biological characteristics to widely varying degrees; the interactions influence how characteristics are expressed in individuals.

B. Some genetically-based characteristics will be exhibited despite the cultural context (e.g. albinism).

C. Other characteristics reflect the interaction of environment and genes (e.g. intelligence, body shape, and growth).

IV. Diet and Nutrition through the Life Course A. Nutrition has an impact on human growth at every stage of the life cycle; few aspects of the human environment have changed as much in the last 10,000 years as diet.

1. There have been changes in growth rates and outcomes.

2. A woman’s diet during pregnancy can have irreversible effects on her fetus and even transgenerational effects on her grandchildren, because a woman’s supply of eggs is developed while she is in utero.

3. Nutritional stress during pregnancy commonly results in low birth-weight babies that are at great risk for developing hypertension, cardiovascular disease, and diabetes later in life.

B. Another aspect of nutrition is the relationship between diet and the gut microbiome: 1. At birth the infant gut is sterile, but it soon develops the beneficial bacteria that will most influence lifelong health.

2. The microbiome of Caesarean-born versus vaginally-born infants varies.

C. The nutrients needed for proper growth and development include proteins, carbohydrates, lipids, vitamins, and minerals.

1. The fact that we require a specific pattern of amino acids, essential amino acids, in our diet reflects our ancestral diet, which was high in animal proteins. a. The preagricultural diet was high in animal protein, complex carbohydrates, and calcium, and low in saturated fats and salt. b. Modern diets tend to have the opposite composition.

2. Problems occur in populations that have only recently adopted milk products and cereal grains into their diets. a. Some people have difficulty digesting dairy products because they lack the enzyme necessary for breaking down the milk sugar lactose.

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b. Others have difficulty digesting gluten found in some cereal grains.

3. Human health has declined in most parts of the world, beginning about 10,000 ya.; referred to as an “epidemiological transition” marked by rise of infectious and nutritional deficiency diseases.

D. Many characteristics evolved because they contributed to adaptation; today the same characteristics are maladaptive.

1. Our evolved capacity to store fat due to high variance in its abundance has become a detriment in modern societies where fatty foods are abundant.

2. Type II diabetes is clearly linked to dietary and lifestyle behaviors that de-emphasize physical activity and emphasize the consumption of fats and refined carbohydrates.

E. Along with the narrowed food base that resulted in the emergence of agriculture, the increase in human population that occurred when people began to settle is to blame for the deficiencies and excesses of nutrients that can cause health problems F. The adoption of Western diets and lifestyles has contributed to declining health in much of the world.

G. In thirty years the focus of the World Health Organization has shifted from undernutrition and infectious diseases to overnutrition and the diseases and disorders associated with obesity.

H. Other Factors Influencing Growth and Development: Genes, Environment, and Hormones 1. Genetics sets the underlying limitations and potentials for growth and development, but environment and life experience have significant effects on phenotype.

2. Twin studies provide information regarding the relative environmental and genetic contributions to variance in phenotypic expression. a. Instructions for turning some genes on and some genes off are known as epigenome. b. In different individuals, the epigenome may turn off some genes or turn on others, resulting in different phenotypes. c. Explains why one identical twin may suffer from a genetically-based cancer while the other is disease free. d. Epigenetics helps reveal that the structural changes to DNA and associated proteins can underlie gene expression.

3. Hormones are substances produced in cells that affect other cells. Most hormones are produced in endocrine glands, and most of these hormones have an effect on growth. a. The growth hormone, secreted by the anterior pituitary, promotes growth and has an effect on just about every cell in the body. i.

The short stature of the African Efe pygmies is an example of the interaction between biological and cultural factors. b. Cortisol also influences growth and development; elevated during stress, the prolonged or severe consequences can have negative effects on health and behavior. c. The disconnection between today’s hormonal profiles and those of our ancestors may result in a higher incidence of reproductive cancers, especially when coupled with highfat diets and low levels of exercise.

V. Life History Theory and the Human Life Course A. Life history theory refers to how natural selection has operated on the life cycle from conception to death: 1. The entire life course represents a series of trade-offs among various life history traits, based on the premise that there is only a certain amount of energy available to an organism for growth, maintenance of life, and reproduction.

2. Humans have more life cycle phases than any other species.

3. Life cycle stages are marked by biological transitions which occur in culturally-defined contexts. a. Menarche is often marked with ritual and celebration.

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b. Menopause is associated with a rise in status of women in non-western societies.

B. Pregnancy, Birth, Infancy, and Childhood 1. The expectations for a pregnant women’s behavior are culturally-regulated and therefore diverse, yet most societies proscribe women from ingesting toxins that would endanger the fetus. a. Food aversions and the nausea that many women experience during pregnancy may be adaptations to protect the fetus.

2. What happens during prenatal development has lifelong consequences.

3. The human newborn is huge at birth compared to the mother’s body, approximately 6 percent of her adult size. a. At birth the infant’s brain is 25 percent of what it will be at adult stage. b. It will reach 50 percent of its adult size by the age of 6 months. c. It is believed that the brain does most of its development after birth because of the metabolic costs of its development and also the need for a stimulating cultural and social environment in which to develop.

4. Infancy is the period during which nursing takes place. a. Nursing typically lasts two years among humans. b. Among foragers, though, and apes nursing typically lasts three to four years. (i) Human milk, and primate milk in general, is low in fats and proteins, which necessitates frequent and prolonged nursing. This also suppresses ovulation and helps maintain a natural birth interval. (ii) Breast milk provides antibodies that contribute to infant survival.

5. Childhood: humans have an unusually long childhood (the time between weaning and puberty): a. This is an important time when brain growth is completed and social learning takes place. b. The major causes of childhood death are infectious diseases exacerbated by poor nutrition.

6. Adolescence is marked by a number of biological events. a. Hormone production results in increases in body size and changes in body shape. Girls develop breasts, and boys’ testes and penises develop further: (i) During adolescence, there is a period when well-nourished teens typically increase in stature at greater rates than at other times in the life cycle. This is called the adolescent growth spurt. b. Menarche (the first menstruation) is a sign of puberty in girls. c. As in all primates, human females reach sexual maturity before males, and the onset of sexual maturity is influenced by the interaction of the environment and genes. (i) Over the past 100 years, there has been a trend towards a decrease in the age of menarche. (ii) Producing offspring as early as possible may have contributed to the reproductive success of females, especially under conditions when life expectancy would have been low.

7. Adulthood is achieved (in the biological sense) when sexual maturation is complete. a. Levels of hormones produced during the menstrual cycle may be higher in women from industrialized societies than those living lives more similar to those of our ancestors. (i) Menopause marks a female’s entry into the postreproductive period. b. Among primates, human females have exceptionally long postreproductive periods: (i) There is a period of 12-15 years beyond the birth of the child that the child is dependent. (ii) The “grandmother hypothesis” proposes that natural selection favors menopause because postmenopausal women can provide high-quality care for their grandchildren.

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(iii) Menopause may be an artificial byproduct of the extension of the human life span.

VI. Aging and Longevity A. The physiological onset of “old age” is not well defined. In the United States, we tend to associate old age with decreased physical activity and increased incidence of disease.

1. In most societies, however, old age does not have these negative connotations.

2. Humans tend to live longer now than they did in the past because they are not dying from infectious disease as frequently. Yet, there are many “diseases of civilization.” (a) In the United States, the leading causes of death include heart disease, cancer, stroke, accidents, and chronic obstructive lung disease (over 70 percent of deaths).

B. Humans have a relatively long lifespan, the maximum 120 years.

C. We think of aging as senescence, the process of physiological decline that occurs toward the end of life course; actually there is a gradual decline.

1. One explanation for why we age is that the genes that enhance reproduction in early years have detrimental effects later in life. Genes with multiple effects are called pleiotropic genes.

2. Others have pointed to the effects of free radicals (molecules that damage cells) on senescence. This is the mitochondrial theory.

3. The “telomere hypothesis” argues that as cells continually divide, their telomeres (the DNA sequence at the end of each chromosome) become progressively shorter, somehow negatively impacting the longevity of the cell.

D. The rate at which we age is also affected by lifestyle factors such as smoking, physical activity, diet, and the quality of medical care.

1. Women universally have higher life expectancies than men.

2. Life expectancy at birth varies from country to country and among socioeconomic classes.

Rates in the U.S. appear to be slowing relative to other industrialized societies (ranked 36th among nations of the world.)

VII. Are We Still Evolving?

A. Yes, but we cannot answer the question of whether we will become a different species in the future; since extinction is the ultimate fate of almost every other species on the Earth, it is likely we will go extinct at some point in the future.

1. Humans are constantly exposed to new environments and new diseases, and children continue to die due to limited medical care and malnutrition; gene frequencies continue to change.

2. Culture has enabled us to transcend many of our biological limitations.

Key Terms and Concepts Adolescent growth spurt, p. 354 Endocrine glands, p. 348 Epigenetics, p. 348 Epigenome, p. 348 Essential amino acids, p. 344 Menarche, p. 350 Menopause, p. 350 Microbiome, p. 344 Pleiotropic genes, p. 357 Senescence, p. 356

Lecture Suggestions 1. Recent research suggests that women who postpone reproduction until their thirties or forties run a significant risk of having children with physical or mental disabilities, or of not being able to have Copyright © 2017 Cengage Learning. All Rights Reserved.

children at all due to the degeneration of the female’s eggs. Discuss how social evolution in industrialized societies has favored women joining the work force and delaying pregnancy, at the same time ensuring that the reproductive capability is preserved.

2. Discuss the “small but healthy” hypothesis and the criticisms of this argument. Include the implications for public health efforts throughout the world.

3. Outline what has changed in the environment of our ancestors, both naturally and culturally. Suggest the consequences of continued changes. One medical/cultural practice that you can discuss is the selective effects of Caesarean versus vaginally-delivered infants. How have medical interventions affected selective forces in evolution?

4. Examine the cross-cultural significance of birth and puberty rites. How do different societies mark these events differently? Why?

Internet Exercises 1. Go online and find out about Otzi, the 5,300 year-old body of a man discovered in the Alps in 1991 (use the search term “Otzi ice man”). See pictures of what he may have looked like http://news.nationalgeographic.com/news/2011/02/pictures/110225-otzi-iceman-new-face-sciencemummy-oetzi/, his discovery http://ngm.nationalgeographic.com/2007/07/iceman/icemanphotography and his diet and lifestyle http://www.pbs.org/wgbh/nova/ancient/iceman-last-meal.html.

2. Explore NOVA, PBS website on the complexity of the recent field of epigenetics, the way in which “Our lifestyles and environment can change the way our genes are expressed, leading even identical twins to become distinct as they age.” http://www.pbs.org/wgbh/nova/sciencenow/3411/02.html 3. Study the chart illustrating the growth of the 65+ age group, 1900 to 2050 http://www.trinity.edu/mkearl/over65.jpg. What does this suggest in terms of changes, if any, to the definition of “old age” in the U.S.?

Multiple Choice Questions 1. With the origin of food production, the pace of cultural change began to speed up. Approximately how many years ago did this dramatic shift occur? a. 1.2 million years ago b. 100,000 ya c. 100 ya d. 5,000 ya e. 10,000 ya ANS: e REF: Evolved Biology and Contemporary Lifestyles – Is There a Mismatch?

2. All of the following are ways that cultural values affect growth and development except: a. in some cultures males receive better nutrition than females. b. in some cultures women restrict their dietary intake to be very slim. c. in some cultures the marriage customs do not allow women and men to live together. d. in some cultures the populations live at extreme altitudes. e. in some cultures there is an increased risk for certain genetic diseases.

ANS: c REF: Biocultural Evolution and the Life Course 3. At birth, the human brain is approximately what percent of its adult size? a. 15 percent b. 25 percent Copyright © 2017 Cengage Learning. All Rights Reserved.

c. 50 percent d. 75 percent e. 100 percent ANS: b REF: Life History Theory and the Human Life Cycle 4. The human brain reaches 50 percent of its adult size by what age? a. 3 years b. 5 years c. 6 months d. 1 month e. 21 years ANS: c REF: Life History Theory and the Human Life Course 5. The human preagricultural diet was: a. high in fats and low in carbohydrates. b. high in fats and animal proteins. c. low in saturated fats and high in animal proteins. d. low in complex carbohydrates and calcium. e. high in salt and low in fiber.

ANS: c REF: Diet and Nutrition through the Life Course 6. What is a present day disorder that is clearly linked to dietary and lifestyle behaviors, such as decreased activity levels and increased consumption of fats and refined carbohydrates? a. HIV b. SIV c. Malaria d. Smallpox e. Diabetes ANS: e REF: Diet and Nutrition through the Life Course 7. There are 22 amino acids. How many of these must be obtained from the food we eat because they are not synthesized in the body in sufficient amounts? a. 22 b. 3 c. 9 d. 10 e. 1 ANS: c REF: Diet and Nutrition through the Life Course 8. One primary way in which genes have an effect on growth and development is through: a. nerves.

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b. c. d. e.

the chromosomes. hormones.

DNA replication. mitosis.

ANS: c REF: Life History Theory and the Human Life Course 9. Environmental factors: a. have no effect on growth and development. b. have not been studied in regards to their effects on growth and development. c. definitely have effects on growth and development. d. always have negative effects on growth. e. call into question any effect of hormone glands.

ANS: c REF: Life History Theory and the Human Life Course 10. Which hormone listed below is among those most important in growth? a. Insulin b. Hemoglobin c. Gluten d. Lactose e. Hormones that only activate in gestation ANS: a REF: Diet and Nutrition through the Life Course 11. Infectious diseases have their greatest effect on growth and development during which life phase? a. Adulthood b. Menopause c. The postreproductive years d. Childhood e. Senescence ANS: d REF: Life History Theory and the Human Life Course 12. Infectious diseases can delay growth, particularly when coupled with: a. poor nutrition. b. too much protein consumption. c. adequate vitamin D. d. humidity. e. technologies introduced by Western culture.

ANS: a REF: Life History Theory and the Human Life Course 13. Life history theory seeks to do all of the following except: a. seeks to answer why humans have long periods of infancy and childhood. b. seeks to have a non- evolutionary perspective.

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c. seeks to understand the impact of natural selection on life cycles. d. allows us to predict the timing of reproduction under favorable conditions. e. suggests that the life course is a series of trade offs.

ANS: c REF: Life History Theory and the Human Life Course 14. The adolescent stage is present in which of the following? a. All mammals b. All primates c. Humans only d. Monkeys, apes, and humans e. All nonhuman primates except orangutans ANS: c REF: Life History Theory and the Human Life Course 15. A long period of female postreproductive time is found in which of the following? a. Chimpanzees b. Gorillas c. All monkeys d. Lemurs e. Humans ANS: e REF: Aging and Longevity 16. What is the term for a female’s first menstruation? a. Menopause b. Menarche c. Andropause d. Andrenarche e. Epigenome ANS: b REF: Life History Theory and the Human Life Course 17. The study of changes in phenotype that are not related to changes in the DNA and that may result from the interaction between the genotype and the environment: a. menarche. b. adaptation. c. homeoplasty. d. epigenetics. e. pleiogenetics.

ANS: d REF: Diet and Nutrition through the Life Course 18. At birth the infant gut is sterile, but it is quickly populated by a host of microorganisms that will influence lifelong health. This is referred to as: a. adolescent growth spurt.

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b. c. d. e.

bacterial microbial environment. pleiotropic effects. epigenic environment. the microbiome.

ANS: e REF: Diet and Nutrition through the Life Course 19. Human milk, like that of other primates, is: a. high in fats. b. high in nutrients. c. low in antibodies. d. low in fats. e. low in supply, hence frequent nursing is required.

ANS: d REF: Life History Theory and the Human Life Course 20. Which of the following is not true about human childhood? a. Humans have unusually long childhoods. b. Childhood is key to learning in humans. c. It is defined as the time between weaning and puberty. d. It is an extremely short stage of human life. e. It is a vulnerable stage of human development.

ANS: d REF: Life History Theory and the Human Life Course 21. Biological events that mark the transition to adolescence include all of the following except: a. increase in body size. b. hormonal changes. c. changes in body shape. d. decrease in stature. e. increased development and enlargement of breasts and penises.

ANS: d REF: Life History Theory and the Human Life Course 22. What is the term for the period following the last menstrual cycle in human women? a. Menarche b. Menopause c. Adrenarche d. Egg-pause e. Cyclopause ANS: b REF: Life History Theory and the Human Life Course 23. In the United States, old age is usually associated with all of the following except: a. physical ailments. b. decreased activity.

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c. rapid rise in female social status. d. negativity. e. unwelcome attitudes.

ANS: c REF: Aging and Longevity 24. What does the “grandmother hypothesis” propose to explain? a. The age of onset of menopause b. The age of puberty for males c. The age of onset of menarche d. The existence of menopause e. The existence of estrogen production ANS: d REF: Life History Theory and the Human Life Course 25. _______ genes have multiple effects at different times in the life span or under different conditions. a. Ontogenetic b. Telomere c. Pleiotropic d. Hidden e. Dominant ANS: c REF: Aging and Longevity 26. One hypothesis that proposes to explain senescence notes that cells that divide throughout the life course have shortened DNA sequences at the end of the chromosomes. This is referred to as the ________ hypothesis. a. hadromere b. carsonomere c. telomere d. intron e. old age ANS: c REF: Aging and Longevity 27. The enzyme telomerase is characterized by all of the following except: a. codes for an enzyme that can lengthen telomeres. b. can make cells function as young again. c. has been called the “immortalizing gene.” d. allows for the cell to cease to divide. e. can contribute to understanding cellular function and cancer.

ANS: d REF: Aging and Longevity 28. Before the AIDS epidemic in Africa, Botswanans had a life expectancy of 65 years. At the height of the epidemic it was about ______ years.

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a. b. c. d. e.

15 40 60 75 85

ANS: b REF: Aging and Longevity 29. The age of onset of menarche is affected by all of the following except: a. genetic patterns. b. nutrition. c. stress. d. disease. e. telomerase.

ANS: e REF: Life History Theory and the Human Life Course 30. The decline in physiological functioning associated with aging is called: a. senescence. b. menarche. c. adolescence. d. dementia. e. pleiotropy.

ANS: a REF: Aging and Longevity

True/False Questions 1. The contemporary diet typical of industrialized societies is basically unchanged from preagricultural diets.

ANS: False REF: Evolved Biology and Contemporary Lifestyles – Is There a Mismatch?

2. Our ability to store fat was adaptive in the past but is maladaptive in industrialized societies.

ANS: True REF: Diet and Nutrition through the Life Course 3. Both nutritional deficiencies and excesses can cause health problems and interfere with childhood growth.

ANS: True REF: Diet and Nutrition through the Life Course 4. The prenatal life cycle phase begins with conception and ends at weaning.

ANS: False

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REF: Life History Theory and the Human Life Course 5. Birth is an event that is celebrated with ritual only in the United States and Europe.

ANS: False REF: Life History Theory and the Human Life Course 6. The language centers of the human brain develop in the first three years of life.

ANS: True REF: Life History Theory and the Human Life Course 7. Humans have unusually short childhoods, reflecting the importance of learning in our species.

ANS: False REF: Life History Theory and the Human Life Course 8. Most anthropologists agree that human populations are not evolving anymore.

ANS: False REF: Are We Still Evolving?

9. Intelligence reflects the interaction of environment and genes.

ANS: True REF: Biocultural Evolution and the Life Course 10. Cultural values affect growth and development.

ANS: True REF: Biocultural Evolution and the Life Course 11. Far more important than genes in the aging process are lifestyle factors.

ANS: True REF: Aging and Longevity

Short Answer Questions 1. Explain the way a woman’s diet during pregnancy can have an impact on her future child and grandchildren.

ANS: It changes the hormonal profile of the mother during her pregnancy and so has a direct effect on the development of the child and the resulting growth and development of that individual through their lives and into the next generation.

REF: Life History Theory and the Human Life Course 2. Define the meaning of adolescent growth spurt.

ANS: This is the period during adolescence when well-nourished teens typically increase in stature at greater rates than at other times in the life cycle.

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REF: Life History Theory and the Human Life Course 3. What are essential amino acids and what do the specific amounts we need of these nutrients suggest for modern societies?

ANS: These are the 9 of the amino acids that must be obtained from our foods because they are not synthesized sufficiently in the body. In modern societies, the foods we consume often do not relate favorably with these needs.

REF: Diet and Nutrition through the Life Course 4. Describe the pattern of human brain growth. What is the importance of delayed brain growth in humans?

ANS: At birth the brain is 25 percent of its adult size and 50 percent by 6 months. Delayed brain growth is possibly caused by high metabolic needs and the inability of the mother’s body to keep up with the demands of a larger brain. In addition, the birth canal is restricted in size.

REF: Life History Theory and the Human Life Course 5. Compare the hypothesized preagricultural diet with the diet consumed by most Americans today.

ANS: The preagricultural diet, unlike our modern one, was lower in saturated fats and high in animal protein.

REF: Diet and Nutrition through the Life Course 6. What are some of the explanations for the recent trend toward a lower age of menarche?

ANS: Because of diet and healthcare, there has been a trend recently toward a lower age of menarche.

It is very sensitive to environmental context.

REF: Life History Theory and the Humans Life Course 7. Define senescence. Discuss one hypothesis that attempts to explain senescence.

ANS: It is a decline in physiological functioning usually associated with aging. The various theories that can be discussed are pleiotropic theory, mitochondrial theory, and telomere hypothesis.

REF: Aging and Longevity 8. What are pleiotropic genes and what do they help us to understand?

ANS: These are genes that have more than one effect at different times in the life cycle. They help us understand the environmental effects that interact with our biology.

REF: Aging and Longevity

Essay Questions 1. List and describe the life cycle stages of humans.

ANS: Will vary REF: Life History Theory and the Human Life Course 2. Discuss the genetic, hormonal, and environmental factors influencing human growth and development.

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ANS: Will vary REF: Life History Theory and the Human Life Course 3. Answer the question, “are we still evolving?” by highlighting socioeconomic and political concerns.

ANS: Will vary REF: Are We Still Evolving?

4. What are the consequences of the tremendous changes in the environment, some of which you have seen in your own lifetime?

ANS: Will vary REF: Diet and Nutrition through the Life Course

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CHAPTER 14: THE HUMAN DISCONNECTION Chapter Outline I.

Introduction A. Humans are the result of biocultural evolution.

1. Modern human biology and behavior have been shaped by the biological and cultural forces that operated on our ancestors.

2. Culture and technology have allowed us to adapt and impacted other species and the planet.

B. Humans are responsible for global climatic change. There is an overwhelming consensus that global warming is occurring.

C. We are living during a critical period of earth’s history, the future of the planet and its biodiversity will be decided by our choices and will be irrevocable.

II.

Human Impact on the Planet and Other Life-Forms A. Currently 7 billion humans live on the planet; of other life-forms, bacteria, as reproducing organisms, number the most.

B. In the past ancestors responded primarily to challenges in the natural world; today, the greatest challenges are the vastly altered environments of our own making.

C. By our actions, which have caused widespread devastation of ecosystems, we have disconnected our species from its long evolutionary history.

D. Increasing population size is perhaps the single most important reason that our impact has been so great.

1. 10,000 years ago the population was 5 million; by 1800, 1 billion.

2. 1 billion added every 13 years.

3. 95% of population growth in developing countries.

4. A small percentage of the world’s population controls and consumes most of the world’s resources; 2011 study estimated that 48% of world’s population exists on less than $2/day.

E. Humans and the Impact of Culture: Technologies remained simple until about 15,000 years ago when humans became more settled. With the domestication of animals and plants, humans began to have a significant effect on the planet as human populations increased due to stable food supplies.

1. The domestication of plants and animals is one of the most significant events in human history with far-reaching consequences. a. Humans began to exploit and increasingly depend on nonrenewable resources. b. Forest clearing was followed by soil erosion, overgrazing, and over cultivation.

2. Destruction of natural resources in the past has had severe consequences for people living today a. Deforestation has led to some of the most devastating floods and erosion in various areas such as China, Bangladesh, and Pakistan.

III.

Global Climate Change A. Much of the energy needed is derived from the burning of fossil fuels, e.g. oil and coal.

B. Increased production of carbon dioxide and other greenhouse gases is a great concern when anticipating climate change in the form of global warming.

1. Climatic fluctuations have occurred in the past, many sudden and with devastating consequences.

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2. Human-produced greenhouse gases could tip the balance toward a catastrophic global climate change.

3. There is more carbon dioxide in the earth’s atmosphere than at any other time in the last 800,000 years.

4. We can expect dramatic changes in weather patterns, along with alterations in precipitation levels.

C. Currently about 70 percent of Americans believe the climate is changing and as many as 40 percent agree that it is due to human activity: 1. Global warming is now as controversial as evolution in the United States.

2. Many school districts do not teach it and some officials (such as in Florida) have been instructed not even to use the terms “global warming” and “climate change.”

3. There is a group of skeptics who insist that climate change is not occurring: a. They call themselves “climate deniers” and “skeptics.” b. Their skepticism is motivated primarily by ideology or financial gain. c. There have been studies to show that over time (since 1753), from hundreds of reporting sites, that global warming is real and humans are almost entirely the cause (Richard Muller study).

D. The problems with climate science are mainly caused by a poor science education in the public: 1. There are thousands of variables involved.

2. There are few definitive answers.

3. There are often contradictions and contradictory results.

E. 2014 was the warmest year on record worldwide. Despite the existence of snow and snowballs during the winter (an act carried out by Senator Inhofe onto the Senate floor), 2014 was a recordbreaking year.

1. 2015 is expected to break the record of 2014.

2. The reason for the severe weather is the shift in the jet stream: a. It has changed its normal course and moved more to the south. b. This shift is believed to have occurred because of the warm temperatures in the Arctic area.

F. There have been changes in the polar ice: 1. 50 mya there was no ice in the Arctic regions and much of the planet was covered in tropical forests. a. Around 1.8 mya in the Pleistocene there was glacial advance and retreat.

2. Today there is more carbon dioxide in the earth’s atmosphere than at any point in human history.

3. In 2007 scientists became alarmed at the sudden unexpected increase in the loss of Arctic sea ice: a. Sea ice reflects back into space some 80 percent of the sunlight that reaches it, while sea water absorbs about 90 percent of the sunlight. b. Scientists have been tracking Arctic sea ice maximum and sea ice minimum from satellites in an attempt to predict the rate at which it is being lost. c. In 2012, it was measured at 49 percent lower than in the 1979-2000 average. d. In 2015 the Arctic reached another milestone with low sea ice levels and many scientists are concerned that the polar regions might have reached a “tipping point,” a point beyond which warming cannot be reversed.

4. There are potential positive impacts, such as quicker travel times for ships, but the consequences are not possible to predict with complete accuracy.

G. There has been increasing drought in areas such as California and flooding on the East Coast (Hurricane Sandy): 1. There have been Category 5 typhoons affecting Asia and other types of severe weather.

2. Flooding and desertification cause additional problems:

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a. Erosion and loss of agricultural lands. b. Altered patterns of infectious disease. c. Increased human hunger. d. Extinction of numerous plants and animals.

H. We can expect increasing acidification of oceans due to absorption and greater amounts of CO2.

1. Levels will reach those not seen in oceans for the past 20 million years.

2. Destruction of tropical coral reefs that contain 25% of all ocean-dwelling species and feed more than 100 million people.

3. Longer effects will be seen worldwide: 20-25% of world’s protein consumption comes from marine sources.

I. World’s governments recognize the crisis and have convened global meetings: 1. 2009 United Nations sponsored International Convention on Climate Change in Copenhagen, Denmark.

2. 2012 United Nations Conference on Sustainable Development in Rio de Janeiro, Brazil.

3. November 2014 United States and China announced a mutual agreement regarding climate to target levels of emissions.

4. Another conference is set for 2015 in Paris.

5. In May 2015, Pope Francis issued a papal encyclical condemning humanity’s destruction and exploitation of the natural environment and loss of biodiversity.

IV.

Impact on Biodiversity A. Humans are the “world’s greatest evolutionary force,” having a profound effect on the evolutionary histories of almost all forms of life.

B. There have been at least fifteen mass extinctions in the past 570 million years caused by natural events.

1. 250 mya climate change was followed by the joining of all the earth’s landmasses.

2. 65 mya tens of thousands of species were eradicated, including most dinosaurs.

3. The third event, beginning in the late Pleistocene or early Holocene, the event is caused by humans, marking the “Anthropocene.”

C. Hunting and clearing land have taken their toll on nonhuman species.

1. Hunting is a major factor.

2. Competition among introduced non-native species has contributed to the problem.

3. Habitat destruction is the most important single cause.

D. Habitat loss is the direct result of growing human population.

1. 2010 United Nations conference on biodiversity was encouraging. a. Reduce ½ or bring to zero the rate of loss of all natural habitats. b. Reduce pollution to levels that are not detrimental to ecosystems and biodiversity. c. Conserve at least 17% of terrestrial areas and 10% of coastal and marine areas in protected zones. d. Prevent extinction of known threatened species. e. Restore at least 15% of degraded ecosystems.

V.

Acceleration of Evolutionary Processes A. Of concerns is also the growth of the evolutionary process of hundreds of bacterial and viruses.

1. Many have changed in one human lifetime, not the millions of years usually associated with evolution.

B. Use of antibiotics has altered the course of evolution of several bacterial diseases; several are resistant to antibiotics.

1. Human technology and lifestyles are responsible for the deadly nature of some of the “new” diseases arising in recent years, e.g. HIV/AIDS, dengue hemorrhagic fever, Lyme disease.

2. Without antibiotics, many bacteria have the ability to increase mortality.

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C. Use of pesticides and insecticides on agricultural crops has posed a similar problem.

1. Even the American bald eagle was severely threatened because of DDT use.

D. Understanding the evolutionary process is paramount to foreseeing the long-term consequences of human actions.

VI.

Looking for Solutions A. What will the world be like in 2050, when the world’s population is estimated to be 10 billion?

1. Industrialized nations must help developing countries adopt fuel-efficient technologies without increasing output of greenhouse gases.

2. Family planning must be adopted to stop population growth.

B. Behavioral change is difficult; easy to ask others to change.

1. The average American consumes 400 times the resources of a person in Bangladesh.

2. The United States alone produces 25 to 30 percent of the world’s carbon dioxide emissions.

3. Wilson’s theory on allocation of resources per person (ecological footprint) compares developing countries’ ecological footprint size of 2.5 acres, with Americans’ at 24 acres. This means that for all people in the world to match the consumption levels of the United States, four planet earths would be necessary.

4. Clearly, much of the responsibility for the world’s problems rests on the shoulders of the industrialized West.

VII.

Is There Any Good News?

A. The rate of population growth is slowing.

1. The best strategies for reducing family size and world population are to educate girls and women.

2. Improvements in environmental conservation and habitat preservation follow.

3. Ecotourism has become a primary industry in locations such as Costa Rica.

B. Wealthy individuals have begun to invest their fortunes to help reduce poverty and poor health.

C. International cooperation is apparent.

Key Terms and Concepts Holocene, p. 372 Jet stream, p. 368 Sea ice maximum, p. 369 Sea ice minimum, p. 369 Lecture Suggestions 1. Use the information about “The Coming Pressures of Immigration” assembled by the RAND Corporation. According to the report, “The sustained low fertility characteristic of developed countries produces rapidly aging populations. By 2025, for example, the median age of the U.S. population will rise from 34 to 43 years. In Germany, it will increase from 39 to 50 years. Onequarter of the German population will be over 65, and the number of new labor-force entrants will decline by one-third. This phenomenon raises crucial questions about how such societies will support increasing numbers of older people with fewer younger workers and where they will find new entrants into the labor force. Opening their doors to immigrants from countries with rapidly expanding populations is one response the developed countries might consider. For the time being, such immigration pressures are being resisted as only a handful of developed countries admit immigrants in any substantial numbers. Several European countries admit a small number of refugees for humanitarian reasons, but restrict entry for other immigrants. Japan, which faces the prospect of

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losing a quarter of its population over the next 25 years, makes little allowance for immigrants.” http://www.rand.org/pubs/research_briefs/RB5044/index1.html 2. Present clear, obtainable goals that individuals in your community can take to address the world’s ecological problems.

3. Go through and discuss the various international conferences mentioned in the chapter and look at their goals and achievements. How have these changed over the last decade? Is there a growing consensus worldwide?

Internet Exercises 1. Go online to the U.S. Environmental Protection Agency website http://www.epa.gov/ for an overview of the national policies to monitor the global warming problem. Then visit the 2011 UN Framework Convention on Climate Change website http://unfccc.int/2860.php for information at the international level.

2. View the video clip “Story of Stuff” http://www.youtube.com/watch?v=9GorqroigqM and then list the effects of consumption on the planet.

3. Read the United Nations Department of Economic and Social Affairs’ Population Division estimates and projections of world, regional and national population size and growth and demographic indicators. In it the long-range projections are made at the national level, that is, for each of the 228 units constituting the world. In addition, the time horizon for the projections is extended to 2300, so as to allow for the eventual stabilization of the population in at least one scenario. A series of essays on the issue of long-range projections have also been incorporated in this report, enriching the debate on this important topic. Experts from outside the United Nations, many of whom took part in the technical working group meetings, authored these essays. http://www.un.org/esa/population/publications/longrange2/WorldPop2300final.pdf 4. Go to the NASA site on climate change and global warming at http://climate.nasa.gov/ and help student assemble portfolios of known challenges, including those they can name locally in their own communities.

Multiple Choice Questions 1. If we use the criteria of cell numbers, then _______ are the dominant life form on the planet. a. bacteria b. viruses c. humans d. cockroaches e. reptiles ANS: a REF: Human Impact on the Planet and Other Life-Forms 2. Culture: a. has not been an important factor in the evolutionary success of humans. b. is a means by which humans adapt beyond biology. c. has been a limiting factor in the evolution of humans. d. does not have profound effects on the choices we make. e. has not impacted the lives of other species on the planet.

ANS: b REF: Human Impact on the Planet and Other Life-Forms

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3. For most of human history: a. technology has been complex. b. technology has been simple. c. the rate of culture change was rapid. d. culture change was not affected by climate change. e. human impact on local environments decreased as people began to live in permanent settlements.

ANS: b REF: Human Impact on the Planet and Other Life-Forms 4. Scientists estimate that around 10,000 years ago ___________people inhabited the earth. a. 10,000 b. 1 million c. 2.5 million d. 5 million e. 1 billion ANS: d REF: Human Impact on the Planet and Other Life-Forms 5. Which of the following epochs is the most recent believed to have begun around 10,000 years ago? a. Holocene b. Pleistocene c. Eocene d. Miocene e. Pliocene ANS: a REF: Impact on Biodiversity 6. The geological record indicates there have been at least _______ mass extinction events in the past 570 million years. a. 5 b. 100 c. 15 d. 150 e. 1,000 ANS: c REF: Impact on Biodiversity 7. Of the mass extinction events occurring in the past 570 million years, _________of them altered all of the earth’s ecosystems. a. one b. two c. three d. none e. four ANS: b

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REF: Impact on Biodiversity 8. Habitat loss is a direct result of: a. burgeoning insect populations. b. flooding due to climate changes. c. increases in human populations. d. increases in animal habitats. e. road building.

ANS: c REF: Impact on Biodiversity 9. “Anthropocene” refers to: a. hunting by humans for reasons other than acquiring food. b. competition between humans and introduced non-native species that results in new bacterial species. c. destruction of human life on earth caused by overpopulation of bacteria. d. a geological era that recognizes sudden and dramatic changes caused by human activities. e. a reflective view of the damage that humans cause river systems and oceans.

ANS: d REF: Impact on Biodiversity 10. In the history of humanity, the most important causes of extinction do not include: a. hunting. b. burgeoning human populations. c. habitat reduction. d. migration. e. clearing land for cultivation.

ANS: d REF: Impact on Biodiversity 11. What is the one single most important reason that human impact on the planet has been so great? a. Increasing population b. The lowered age of menarche and consequent lack of education among women c. Loss of biodiversity d. The decrease in the maximum life span of humans e. Increase in bacterial forms of life ANS: a REF: Impact on Biodiversity 12. Scientists estimate that we add __________ people to the Earth’s population about every 13 years. a. 2 billion b. 200,000 c. 5 million d. 1 billion e. 25 million ANS: d

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REF: Human Impact on the Planet and Other Life-Forms 13. Since the beginning of industrialization, ocean acidity has already increased by: a. 10%. b. 20%. c. 30%. d. 45%. e. 100%.

ANS: c REF: Global Climate Change 14. Pope Francis issues a papal encyclical in 2015 condemning humanity’s: a. rapid rise in population. b. investment in technological change. c. mass migrations. d. dependence on domestication. e. exploitation of the natural environment.

ANS: e REF: Global Climate Change 15. Family planning can slow population growth. One of the best strategies family planning is: a. the shift to more local economies. b. the migration of rural populations to urban centers. c. shifts in employment from manufacturing to agriculture. d. access to family planning. e. education of girls and women.

ANS: e REF: Is There Any Good News?

16. If human population growth rates remain unchecked, it is possible that by the year 2050 human numbers could approach: a. 10 billion. b. 2 billion. c. 500 million. d. 100 billion. e. 25 million.

ANS: a REF: Looking for Solutions 17. With regards to the consensus among the scientific community: a. there is a great deal of doubt that greenhouse gases are building up in the atmosphere. b. there is almost complete agreement that we are seeing the effects of global warming. c. we have yet to see any effects of global warming. d. global warming is not a complex phenomenon. e. most scientists believe it is occurring primarily during summers.

ANS: b

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REF: Global Climate Change 18. The narrow band of strong winds that flows west to east 6 to 8 miles above the earth is called the: a. sirocco. b. tradewinds. c. jet stream. d. Milky Way. e. headwinds.

ANS: c REF: Global Climate Change 19. The 1990 typhoon and floods that killed over 10,000 in Bangladesh is a direct result of: a. the way infrastructure development is set back by population increases. b. deterioration of dams along tributaries of the Indus River. c. problems derived from an increase of people living in low lying permanent settlements and keeping prey species. d. domestication of plants and animals. e. previous destruction of natural resources.

ANS: e REF: Human Impact on the Planet and Other Life-Forms 20. Which of the following statements is false? a. The United States produces 25 to 30 percent of all carbon dioxide emissions. b. The average American consumes 400 times the resources of the average person in Bangladesh. c. The United States has the highest rates of overpopulation. d. For all people on the planet to match the consumption levels of the United States, we would need four more planets. e. The ecological footprint in the U.S. is 24 acres, compared to 2.5 acres in non-industrialized nations.

ANS: c REF: Looking for Solutions 21. Changes in temperatures and rainfall patterns around the world, due to global warming, will not: a. lead to flooding in some regions. b. lead to the desertification of some regions. c. result in the spread of mosquito-borne diseases in some areas. d. change the reproductive rates of the microbes that cause infectious disease. e. be anything less than catastrophic problems in a world of 7 billion.

ANS: e REF: Global Climate Change 22. Clearly, much of the responsibility for the world’s problems rests squarely on the shoulders of the: a. community of research scientists. b. educators of girls and women. c. oceanographers. d. industrialized West. e. nonindustrialized East.

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ANS: d REF: Looking for Solutions 23. Because of global climate change, the jet stream has: a. caused tectonic eruptions. b. reversed its direction of movement. c. stopped and no longer moves. d. changed its normal course. e. intensified and moved northward.

ANS: d REF: Global Climate Change 24. By most standards, Homo sapiens: a. is a successful genera. b. is a successful species. c. constitutes a majority of the living forms on the planet. d. has not altered the face of the planet. e. has managed resources well.

ANS: b REF: Human Impact on the Planet and Other Life-Forms 25. Biologist Stephen Palumbi states that humans are the “world’s greatest evolutionary force.” By this he means: a. we are the strongest on the planet. b. we are the most prolific organism on the planet. c. we are the least destructive on the planet. d. we can destroy ourselves and perhaps all life on earth. e. we do have a profound effect on the evolutionary histories of almost all forms of life.

ANS: e REF: Impact on Biodiversity 26. By tracking sea ice minimum and sea ice maximum, scientists are able to: a. measure the effect of greenhouse gases. b. determine future movements of the jet stream. c. better protect naval fleets during wartime. d. conserve the habitats of polar bears. e. develop effective water policies for Western countries.

ANS: a REF: Global Climate Change 27. Our use of antibiotics has dramatically altered the course of evolution, to the point that: a. antibiotics are no longer significant selective factors causing bacteria to evolve. b. human technology is no longer responsible for the deadly nature of new diseases. c. insecticides are now more prevalent in reducing malaria. d. antibiotics are significant selective factors causing more virulent forms of bacteria. e. at least 15% of degraded ecosystems have been restored.

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ANS: d REF: Acceleration of Evolutionary Processes 28. According to the textbook authors, the problems facing our planet reflect: a. defects in our understanding of the evolutionary process. b. problems inherent in biodiversity. c. worrisome scientific overthinking. d. an adaptive strategy gone awry. e. education policies.

ANS: d REF: Looking for Solutions 29. It appears the world’s population growth has: a. increased due to the decline in mortality rates of children. b. increased due to the use of antibiotics. c. decreased due to increases in income and education. d. increased due to decreases in income and education. e. not been a problem since the advent of agriculture.

ANS: c REF: Is There Any Good News?

30. By ______Costa Rica has been able to preserve much of its forests and wildlife. a. banning hunting b. limiting the rise in childbirth rates c. developing ecotourism d. educating girls and women e. discouraging ecotourism ANS: c REF: Is There Any Good News?

True/False Questions 1. Physical anthropologists do not view culture as a human adaptive strategy.

ANS: False REF: Introduction 2. Some human groups began to abandon their nomadic lifestyles and settled down approximately 15,000 years ago.

ANS: True REF: Human Impact on the Planet and Other Life-Forms 3. The jet stream has been destroyed because of greenhouse gases.

ANS: False REF: Global Climate Change

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4. There have been four million years of evolution in the genus Homo.

ANS: False REF: Introduction 5. In 1990, the people of Bangladesh were unable to cope with the floods since they had no knowledge of irrigation systems.

ANS: False REF: Human Impact on the Planet and Other Life-Forms 6. Many scientists see the production of greenhouse gases by humans as tipping the balance toward a catastrophic global climate change.

ANS: True REF: Global Climate Change 7. It is estimated that about 10 percent of all ocean-dwelling plants and animals on earth live in endangered coastal reefs.

ANS: False REF: Global Climate Change 8. The scientific community is now in almost complete agreement that we are seeing the effects of global warming.

ANS: True REF: Global Climate Change 9. The most immediate risk of acidification of the oceans is to the whales and dolphins off the western coasts of North America.

ANS: False REF: Global Climate Change 10. Using evolution to solve health problems requires medical researchers have training that includes evolutionary theory.

ANS: True REF: Acceleration of Evolutionary Processes

Short Answer Questions 1. Name and discuss two primary ways that humans have impacted the earth and other forms of life.

ANS: Answers will vary widely, but can include things like domestication of plants and animals, use and abuse of antibiotics, carbon emissions, and especially the rise in population.

REF: Human Impact on the Plant and Other Life-Forms 2. What is meant by the term “Anthropocene”?

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ANS: This term is meant to express the “age of humans” and represents a time period in which the environment has been impacted by human behavior.

REF: Impact on Biodiversity 3. What impacts have human-invented antibiotics had on bacteria?

ANS: They have made bacteria increasingly resistant to treatments available.

REF: Acceleration of Evolutionary Processes 4. In what ways have humans contributed to an acceleration of evolutionary processes?

ANS: The primary way is the development of antibiotic-resistant bacteria and viruses; there has also been overuse and misuse of insecticides and pesticides. These forces frequently result in a more virulent strain to be combated.

REF: Acceleration of Evolutionary Processes 5. What factors are implicated in the near extinction of the bald eagle?

ANS: The use of DDT to combat malaria had a negative impact on the bald eagle and other birds.

REF: Acceleration of Evolutionary Processes

Essay Questions 1. Why are scientists concerned about the loss of ecosystems?

ANS: Will vary REF: Global Climate Change 2. Discuss the nature of the dangers posed by human overpopulation of the planet.

ANS: Will vary REF: Human Impact on the Planet and Other Life-Forms 3. Given the impact of humans on the Earth’s ecosystems, speculate on the future of Homo sapiens.

ANS: Will vary REF: Is There Any Good News?

4. How has public perception affected the understanding and acceptance of climate change?

ANS: Will vary REF: Global Climate Change 5. What are the various methods that scientists use to measure the effect of greenhouse gases on the earth today?

ANS: Will vary REF: Global Climate Change 6. Should we care about the loss of biodiversity? Why or why not?

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ANS: Will vary REF: Impact on Biodiversity

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