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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.)

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.

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

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.”)

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

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?

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?

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

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?

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

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.

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.

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?

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?

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.

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.

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’

(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

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.

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.

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

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

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.

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.

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

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.

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.

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?

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

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. Copyright © 2017 Cengage Learning. All Rights Reserved.

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.

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.

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.

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.

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

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

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.

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

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.

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

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.

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

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

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.

(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.

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

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.

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:

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.

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.

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

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