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CONTRIBUTORS
Shiyi Cao Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
Xiang Cao Department of Materials Science & Engineering, Jinan University, Guangzhou, People’s Republic of China
Hongfei Cheng School of Environmental Science and Engineering, Chang’an University, Xi’an; School of Geoscience and Surveying Engineering, China University of Mining & Technology, Beijing, China
Y. Darrat Louisiana Tech University, Ruston, LA, United States
Hongbing Deng Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
Junjie Ding Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences; School of Materials Science and Engineering, Lanzhou Jiaotong University, Lanzhou, People’s Republic of China
Wenkai Dong Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, People’s Republic of China
Jie Dong Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, PR China
A. Glotov Gubkin Russian State University of Oil and Gas, Moscow, Russia
P. Gushchin Gubkin Russian State University of Oil and Gas, Moscow, Russia
Gaofeng Han School of Materials Science and Engineering, Tianjin Chengjian University, Tianjin, PR China
Jing Huang Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
E. Ivanov Gubkin Russian State University of Oil and Gas, Moscow, Russia
Pascale Launois Laboratoire de Physique des Solides, UMR CNRS 8502, Université Paris Sud, Université Paris Saclay, Orsay, France
Dan Li Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
Jinsheng Liang Institute of Power Source and Ecomaterials Science, Hebei University of Technology; Key Laboratory of Special Functional Materials for Ecological Environment and Information (Hebei University of Technology), Ministry of Education, Tianjin, PR China
Qinfu Liu School of Geoscience and Surveying Engineering, China University of Mining & Technology, Beijing, China
Rong Liu Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
Mingxian Liu Department of Materials Science & Engineering, Jinan University, Guangzhou, People’s Republic of China
Hongzhong Liu Department of Materials Science & Engineering, Jinan University, Guangzhou, People’s Republic of China
Yushen Lu Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, People’s Republic of China
Y. Lvov Gubkin Russian State University of Oil and Gas, Moscow, Russia; Louisiana Tech University, Ruston, LA, United States
Bin Mu Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, People’s Republic of China
A. Novikov Gubkin Russian State University of Oil and Gas, Moscow, Russia
Erwan Paineau Laboratoire de Physique des Solides, UMR CNRS 8502, Université Paris Sud, Université Paris Saclay, Orsay, France
A. Semenov Gubkin Russian State University of Oil and Gas, Moscow, Russia
Iqra Shahzadi Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
A. Stavitskaya Gubkin Russian State University of Oil and Gas, Moscow, Russia
Huiyu Su Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
Guangyan Tian Institute of Power Source and Ecomaterials Science, Hebei University of Technology; Key Laboratory of Special Functional Materials for Ecological Environment and Information (Hebei University of Technology), Ministry of Education, Tianjin, PR China
Dongshen Tong Research Group for Advanced Materials & Sustainable Catalysis (AMSC), College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, People’s Republic of China
V. Vinokurov Gubkin Russian State University of Oil and Gas, Moscow, Russia
Wenbo Wang Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, People’s Republic of China
Aiqin Wang Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-Material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, People’s Republic of China
Fei Wang Institute of Power Source and Ecomaterials Science, Hebei University of Technology; Key Laboratory of Special Functional Materials for Ecological Environment and Information (Hebei University of Technology), Ministry of Education, Tianjin, PR China
Chi Wang Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
Yang Wu Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
Xiaohan Yang Department of Materials Science & Engineering, Jinan University, Guangzhou, People’s Republic of China
Yang Yi Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resource and Environmental Science, Wuhan University, Wuhan, China
Weihua Yu Research Group for Advanced Materials & Sustainable Catalysis (AMSC), College of Chemical Engineering, Zhejiang University of Technology, Hangzhou; Zhijiang College, Zhejiang University of Technology, Shaoxing, People’s Republic of China
Junping Zhang Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, PR China
Yi Zhou School of Geoscience and Surveying Engineering, China University of Mining & Technology, Beijing, China
Chunhui Zhou Research Group for Advanced Materials & Sustainable Catalysis (AMSC), College of Chemical Engineering, Zhejiang University of Technology, Hangzhou; Qing Yang Institute for Industrial Minerals, Chi Zhou, People’s Republic of China; Key Laboratory of Clay Minerals of Ministry of Land and Resources of the People’s Republic of China, Engineering Research Center of Non-metallic Minerals of Zhejiang Province, Zhejiang Institute of Geology and Mineral Resource, Hangzhou, China
Changren Zhou Department of Materials Science & Engineering, Jinan University, Guangzhou, People’s Republic of China
ABOUT THE EDITORS
Aiqin Wang is the Director of Key Laboratory of Clay Mineral Applied Research of Gansu Province and the R&D Center of Eco-materials and EcoChemistry at the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, China. His research focuses on nanoclay-derived functional materials and environment-friendly materials. Currently, he has presided over 40 national and provincial research projects, has published more than 400 papers, and has had 60 patents issued.
Wenbo Wang is a Professor at the Key Laboratory of Clay Mineral Applied Research of Gansu Province and R&D Center of Eco-material and EcoChemistry at the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, China. His research includes dissociation and dispersion of clay minerals as nanoscale for applications in nanocomposites. Currently, he has presided over 10 research projects, has had 30 patents issued, and has published 3 books and more than 130 papers.
PREFACE
Clay minerals are naturally available silicate nanomaterials with diverse morphologies, functions, and wide applications in various fields. The rod-like, fibrous, tubular, and sheet-like clay minerals with nanoscale size and special surface properties are readily available in nature and are used for adsorption and as colloids, carriers, and reinforcing materials. In recent years, there has been significant progress in the theoretical and applied research on clay minerals, but the fields of application of the main products are still limited to some traditional fields. So, extending the application of clay minerals in functional materials through continuous innovations in technology is very important to realize high value utilization of clay mineral resources.
Taking into account the unique advantages conferred by the “from nature, for nature, and into nature” concept, clay minerals have received a lot of attention from researchers in mineralogy, materials science, chemistry, biomedicine, and other fields. On conducting a search using the keywords “clay or clay mineral or clay minerals or clays” on the core database of Web of Science, we retrieved 140,615 records from 1915 to 2019 (as of December 31, 2018), with the subjects involved including geosciences multidisciplinary (24,058 records), soil science (14,935 records), environmental sciences (14,874 records), chemical physical (14,192 records), materials science multidisciplinary (13,996 records), engineering geological (13,608 records), polymer science (9080 records), engineering civil (8491 records), water resources (7457 records), and mineralogics (7248 records). Studies on clay minerals have not been limited only to the fields of mineralogy and geology, but have been extended to the fields of environment, chemistry, physics, engineering, materials science, polymer science, and other fields. The number of published research papers on clay minerals increased from 15 in 1915 to 600 in 1990, but rapidly increased to 1926 in 1991, which is the watershed after which research on clay minerals began to flourish. By 2018, the number of publications increased steeply to 8167, which proves that research on clay minerals has received unprecedented attention. Of course, this is primary reason for the extension of the fields of application for clay minerals.
The great interest in the research on clay minerals has resulted from the promotion by associations, academic exchanges, and the continuous efforts of researchers at home and abroad. Following the establishment of The Clay Mineral Association, at 1952 (the predecessor of this organization is Clay Minerals Committee of the National
Academy of Sciences—National Research Council) the current authoritative journals Clay Minerals and Clays and Clay Minerals were published and annual conferences were held in different regions of the world every year. By 2018, the annual conference has been held for 55 consecutive sessions. At the same time, the European Clay Association and the Asian Clay Association have also played important roles in the development of regional clay mineralogy, local clay minerals research, and industrial development, which has made clay minerals a topic of increasing interest year after year. The Handbook of Clay Science (edited by Faïza Bergaya, B.K.G. Theng, and Gerhard Lagaly, and contributed to by other scholars, e.g., Haydn H. Murray, Manuel Pozo, E. Galán, Peng Yuan, J.-F. Lambert, Mark P.S. Krekeler, Stephen Guggenheim, Mercedes Suárez, Emilia García-Romero, Blair F. Jones, Kathryn M. Conko, Médard Thiry, and Thomas Pletsch to name a few) and other professional books were published, which systematically guided researchers to carry out research on clay minerals. Accordingly, disciplines focused on clay minerals have also been established in universities and research institutes around the world, which have provided a boost to the study of the origin, physical and chemical properties, and applications of clay minerals. Moreover, the scope of the disciplines overlaps many fields of geology, mineralogy, chemistry, and materials science.
Chinese scholars have also contributed a lot to the development of clay sciences, by publishing a large number of research papers and organizing many international conferences on clay sciences. For example, the editors of this book systematically carried out basic and application research studies on palygorskite. They developed a new technology to disaggregate the palygorskite crystal bundles to obtain one-dimensional (ID) nanomaterials. At the 55th Annual Meeting of The Clay Minerals Society, Prof. Aiqin Wang was invited to organize a session on “Palygorskite: From Fundamental Research to Functional Materials.” In 2014, Prof. Chunhui Zhou from Zhejiang University of Technology held the “Workshop on Green Chemical Technology for Clay Minerals-derived Functional Materials and Catalysts” in Hangzhou, China, and published a special issue titled “Clay Minerals Research in China—A Special Issue as an Extension to The Workshop on Green Chemical Technology for Clay Minerals-derived Functional Materials and Catalysts” in Applied Clay Sciences. In October 2018, Prof. Chunhui Zhou organized The Second World Forum on Industrial Minerals (WFIM-2) in Qingyang County, Anhui, China. In November 2016, Prof. Hongping He from the Guangzhou Institute of Geochemistry organized The 3rd Asian Clay Conference “Small Size—Big Science” and published a special issue. In 2018, Prof. Huaming Yang from Central South University as the Section Chair organized the session “Mineral Materials” during the XXII Meeting of the International Mineralogical
Association (IMA2018). Taking into consideration the efforts of clay scientists from all over the world, the successful development of clay mineral science around the world is no longer a dream.
There is no doubt that clay minerals have attracted great interest in the preparation of diverse functional materials owing to their advantages over artificial nanomaterials. This book is a collection of some of the current fundamental and applied research on clay minerals conducted by clay scientists, which provides a glimpse into some of the current activities in clay research all over the world. Such a collection can hardly be expected to summarize all of the current research by clay scientists, much less reflect their past contributions in the field of clay minerals. Keeping this in mind, this book is organized as follows.
Chapter 1 introduces the structure, type, basic properties and application of clay minerals. Chapters 2–5 present the preliminary background concepts of 1D clay minerals palygorskite, sepiolite, halloysite, and imogolite. Chapter 2 reviews the basic structure, properties, modification, disaggregation of crystal bundles, and the composites of palygorskite for traditional and emerging applications. Chapter 3 summarizes the latest research progress on the structure, properties, and modification of sepiolite and its applications in fields such as adsorption, catalysis, environment, polymer composites, and energy. Chapters 4 and 5 introduce the structure, modification, and applications of two tubular clay minerals halloysite and imogolite, respectively.
Chapters 6–9 present the structure, properties, and applications of four types of layered clay minerals with industrial values, namely kaolinite with a T:O = 1:1 layered structure (Chapter 6), smectite with a T:O = 2:1 layered structure (Chapter 7), mixed clay minerals rectorite with a montmorillonite/mica ratio of 1:1 and illite/smectite clay with a variable illite/smectite ratio (Chapter 8), and vermiculite with a T:O = 2:1 layered structure and special thermal expansion properties (Chapter 9). The conversion of these clay minerals into nanomaterials by the use of modern nanotechnology and, correspondingly, the application of these nanomaterials for fabricating advanced functional materials are specifically discussed in these chapters. It is worth noting that although hydroxyapatite is not strictly a clay mineral, it is very similar to clay minerals in many properties and functions, and by compounding it with clay minerals it is possible to improve the performance of clay minerals, which makes the application of clay minerals in the biomedical field possible, so a chapter on hydroxyapatite is covered in this book (Chapter 10).
Chapters 11–13 focus on the important composites based on clay minerals for applications in adsorption, catalysis, hybrid pigments, and biomedicine. Chapter 11 summarizes the latest research achievements in the field of clay minerals/carbon composites. In light of the
unique advantages of halloysite, including their incorporation into polymers after loading some active agents, Chapter 12 introduces many advances in the preparation and characterization of halloysite/ polymer nanocomposites and their application in different fields. Chapter 13 summarizes the research progress on Maya Blue and Maya Blue-like pigments in recent years, where the origin, structure, physicochemical properties, and preparation methods of Maya blue are introduced in detail.
At present, the global focus on clay minerals has developed from geology and mineralogy to functional materials, and the clay mineral industry is also transitioning from traditional industries to emerging industries. We believe that this book will help further promote the indepth study of clay minerals and their functional applications in the field of materials.
We would like to thanks Elsevier and the editors of this book series who invited us to write this book. We also thank the editors from the editorial department for their help in completing this book. The writing of this book was supported by scholars from Louisiana Tech University; Gubkin Russian State University of Oil and Gas; Université Paris Saclay; Wuhan University; Zhejiang University of Technology; Jinan University; China University of Mining & Technology (Beijing); Hebei University of Technology; Chang’an University; Tianjin Chengjian University; University of the Chinese Academy of Sciences; and Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences. We hereby express our heartfelt gratitude to our colleagues and comrades who cared about and participated in the preparation and publication of this book. In addition, during the writing process, we had to frequently refer to the published literature for which we would like to express our sincere gratitude to the authors of the cited references.
Aiqin Wang Wenbo Wang Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, People’s Republic of China
INTRODUCTION
Aiqin Wang, Wenbo Wang
Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-Material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, People’s Republic of China
Clay minerals are a broad class of naturally abundant inorganic nanomaterials with the richer elements on earth such as O, Si, Al, Fe, Ca, Na, K, and Mg as the main composition. The basic structural units of clay minerals are silicon‑oxygen tetrahedrons and metal‑oxygen octahedrons, which are linked by Si O Si or Si O M bonds and com bined together in different ways to form mineral crystals with unique structure and diverse morphologies. With these diverse morpholo gies, e.g., nanorod, nanofiber, nanotube, nanosheet, and nanopore, clay minerals thus have special physicochemical properties, such as large specific surface area, high ion exchange capacity, a great num ber of active surface functional groups. They exhibit excellent colloi dal, adsorption, reinforcing, and carrier functions, as well as nontoxic and eco friendly advantages [1]. Just as the physiological features of organisms are determined by genome, the characteristics of clay min erals are also determined by the composition and combination styles of silicon‑oxygen tetrahedrons and metal‑oxygen octahedrons.
Humans have used clay minerals for thousands of years. In ancient times, various clay mineral derived products such as pottery, drugs, porcelain, mineral pigments, ceramics, and various building mate rials have been widely used. For examples, clay minerals have been found in the world famous Mexican Mayan murals and DunHuang murals in Gansu Province, China. Clay minerals have been used medically to treat diarrhea or wounds. Clay minerals have been used as substrates, bonding additives of bricks and stone, or decoration pigments in various ancient buildings. Clays that are rich in kaolin ite, also known as kaolin or China clay, have been commonly used to make ceramics and chinaware popular in industry and daily life. About 1000 years ago early in the Northern Song Dynasty (AD 960–1127) as the pioneering creator of movable type systems for printing, the Chinese used clay minerals to make movable characters. So, clay minerals played a very important role in the development of human civilization and society. Driven by the significant market demand
1
for clay mineral derived products, research on modern science and the technology of clay minerals has been extensively conducted, and the structure and properties of clay minerals have been thoroughly explained. The basic and applied research on clay minerals also has been extended.
The rapid development of nanoscience and nanotechnology makes it possible to disassociate or strip the clay minerals as nano size units to produce silicate nanomaterials that have been honored as the mate rials of “greening the 21st century material world” [2]. Compared with artificial nanomaterials, natural nanomaterials are enjoying a surge in interest as the “building blocks” of high performance functional mate rials, and they help to improve the quality of product, economize costs, and reduce the environmental burden induced by use of materials. So, the application of clay minerals in functional materials as green addi tives, fillers, or composite components represents the most promising developmental direction for the future. Clay minerals with adsorption capability can be used in the disposal and storage of hazardous chem icals. Clay minerals with catalytic activity can be used to neutralize certain organic hazardous chemicals. Clay minerals with antibacterial activity potentially can be applied in biomedical fields. The study of clay minerals from the perspective of chemistry and material sciences is gradually being used widely and recognized by researchers. This will open up new avenues for the high value added application of clay minerals, and the use of nanotechnology will reduce the size of clay minerals to nanoscale, which offers endless possibilities to design and develop versatile functional materials.
1.1 Types and Classifications of Clay Minerals
Clay minerals, a group of phyllosilicates composed of tetrahedral (T) and octahedral (O) sheets at a certain ratio, are one dimensional (1D) or two dimensional (2D) silicates with sizes <2 μm. According to the AIPEA Nomenclature Committee [3], tetrahedral sheet is com posed of continuous two dimensional corner sharing tetrahedra [TO4]4 involving three basal oxygens and the apical oxygen. The tetrahedral sheet has a composition of [T4O10]4 where T = Si4+, Al3+ , Fe3+. The apical oxygens form a corner of the octahedral coordination unit around larger octahedral cations. The octahedral sheet consists of two planes of closely packed O2 , OH anions of octahedra with the central cations Mg2+ or Al3+. The smallest structural unit con tains three octahedral sites. The trioctahedral structures of phyllosil icates have all three sites occupied with cations (e.g., hydroxide sheet Mg OH 6 12 12 () ). The dioctahedral phyllosilicates have two octahedral
sites occupied with cations (e.g., hydroxide sheet, Al OH 4 12 12 () ), and one site is vacant. The clay minerals with relatively richer reserves in nature and industrial values mainly include kaolinite (the ideal chem ical composition: Al4Si4O10(OH)8), pyrophyllite (Al4Si8O20(OH)4), montmorillonite (Na0.50–1.20[(Al3.50–2.80Mg0.50–1.20)(Si)8O20(OH)4]), illite (K0.50–1.50[(Al4.00)(Si7.50–6.50Al0.50–1.50)O20(OH)4]), sepiolite (Mg4(Si6O15) (OH)2·6H2O), halloysite (Al4Si4O10(OH)8·4H2O), and palygorskite ((Mg, Al)2Si4O10(OH)·4H2O). In the geological formation process, nat ural clay minerals will undergo isomorphic substitution. The cations in the octahedral sheets (i.e., Mg2+, Al3+, Fe3+) and the Si4+ in the tet rahedral sheets are usually replaced by other metal ions, resulting in a significant difference between the practical chemical composition and theoretical value. In addition, the isomorphic substitution caused the generation of structure charges and surface charges. As for 2:1 layer clay minerals (i.e., smectite, vermiculite), the total (negative) layer charge of smectite is between 0.2 and 0.6 p.f.u., and the negative layer charge of vermiculite results from the substitution of Si4+ by trivalent cations in tetrahedral positions. As for the layer chain clay minerals (i.e., sepiolite, palygorskite) composed of one discontinuous octahe dral sheet and two continuous tetrahedral sheets, some trivalent cat ions, e.g., Al3+ and Fe3+ ions, may replace the Mg2+ ions in octahedral sites. The crystallographic defects could be found in the octahedral sheets of natural palygorskite or sepiolite, leading to the generation of structural negative charge and surface negative charge [4].
Different from other clay minerals, the layer charge of kaolinite is commonly close to zero, and the surface charge is variable, which consists of permanent structure charge and surface charge [5]. A small amount of negative structural charge is related to the uncertain iso morphous substitution in the crystal structure. And surface charge is related to the physicochemical process in different medium because of the breakage of Si O and Al OH on edge surfaces, and Al2OH on octahedral gibbsite (Al(OH)3) sheet, leading to the special charge het erogeneity [6]. The surface charges of clay minerals are dependent on the pH of external conditions. The protonation of aluminol groups at the main edge site of clay minerals occurs when they are in aqueous medium with a pH below the point of zero charge (pHpzc). Conversely, deprotonation of silanol and aluminol groups occurs when the pH of aqueous medium is greater than the pHpzc. As the pH increases, the surface charge undergoes a process from positive to zero, and then to negative. When the surface charge is zero, the corresponding pH val ues are listed in Table 1.1.
Grim (1962) first proposed the classification of clay minerals, which became the basis for outlining the nomenclature and the dif ferences between different clay minerals [21, 22]. Grim’s classification
Another random document with no related content on Scribd:
C1 Five toes, nose prolonged into a snout Proboscid’eans
C2
C3
B3 Digits with nails or hoofs
C4
C5
C6
Toes odd number, less than five E’quines Ungulates
Toes even number, upper front teeth lacking, chew the cud Ru’minants
Toes even number, upper front teeth present, not cudchewers Swine
All limbs having hands Quad’rumans
Two limbs having hands Bi’mans
Exercise in Classification. Copy the following list, and by reference to figures write the name of its order after each mammal:
Ape (Figs. 405, 406)
Rabbit (Fig. 345)
Dog (Figs. 356, 408)
Hog (Figs. 357, 393)
Bat (Figs. 347, 370)
Cat (Figs. 337, 348)
Armadillo (Figs. 349, 365)
Cow (Figs. 344, 386)
Walrus (Fig. 340)
Monkey (Figs. 352, 401)
Horse (Figs. 355, 395)
Ant-eater (Figs. 354, 364)
Antelope (Fig. 391)
Mole (Figs. 367, 368)
Beaver (Figs. 372, 373)
Duckbill (Fig. 359)
Tapir (Fig. 384)
Dolphin (Figs. 379, 397)
Use chart of skulls and Figs. 381, 382, 395–400 in working out this exercise. Man’s dental formula is (M ⁵⁄₅, C ¹⁄₁, I ²⁄₂)2 = 32.
In like manner fill out formulas below:
Cow (M C I )2 = 32
Rabbit (M C I )2 = 28
Walrus (M C I )2 = 34
Bat (M C I )2 = 34
Cat (M C I )2 = 30
Armadillo (M C I )2 = 28
Horse (M C I )2 = 40
Whale (M C I )2 = 0
Am. Monkey (M C I )2 = 36
Sloth (M C I )2 = 18
Ant-eater (M C I )2 = 0
Dog (M C I )2 = 42
Hog (M C I )2 = 44
Sheep (M C I )2 = 32
F . 344. Skull and front of lower jaw of C .
The lowest order of mammals contains only two species, the duckbill and the porcupine ant-eater, both living in the Australian region. Do you judge that the duckbill of Tasmania (Fig. 359) lives chiefly in water or on land? Why? Is it probably active or slow in movement? It dabbles in mud and slime for worms and mussels, etc. How is it fitted for doing this? Which feet are markedly webbed? How far does the web extend? The web can be folded back when not in use. It lays two eggs in a nest of grass at the end of a burrow. Trace resemblances and differences between this animal and birds.
The porcupine ant-eater has numerous quill-like spines (Fig. 360) interspersed with its hairs. (Use?) Describe its claws. It has a long prehensile tongue. It rolls into a ball when attacked. Compare its
346. W (see Fig. 341).
jaws with a bird’s bill. It lays one egg, which is carried in a fold of the skin until hatched. Since it is pouched it could be cl assed with the pouched mammals (next order), but it is egglaying. Suppose the two animals in this order did not nourish their young with milk after hatching, would they most resemble mammals, birds, or reptiles?
Write the name of this order. —— (See Table, p. 193.) Why do you place them in this order (——)? (See p. 193.) The name of the order comes from two Greek words meaning “one opening,” because the ducts from the
F . 350. H (front of jaw).
F . 345.—R . A, B, incisors; C, molars
F .
F . 347. B .
F . 348. C .
F . 349. A .
F . 352. A M .
F . 354. A - (Fig. 364).
F . 355. H . bladder and egg glands unite with the large intestine and form a cloaca. What other classes of vertebrates are similar in this?
F . 351. G W .
F . 353. S (Fig. 363).
F . 356. D . Upper (A) and lower (B) jaw.
F . 357. H .
F . 358. S .
F . 359. D (Ornithorhynchus paradoxus).
F . 360. S A - (Echidna aculeata). View of under surface to show pouch. (After Haacke.)
F . 361. O (Didelphys Virginianus).
Pouched Mammals.—These animals, like the last, are numerous in the Australian region, but are also found in South America, thus indicating that a bridge of land once connected the two regions. The opossum is the only species which has penetrated to North America (Fig. 361). Are its jaws slender or short? What kinship is thus suggested? As shown by its grinning, its lips are not well developed. Does this mean a low or a well-developed mammal? Where does it have a thumb? (Fig. 361.) Does the thumb have a nail? Is the tail hairy or bare? Why? Do you think it prefers the ground or the trees? State two reasons for your answer. It hides in a cave or bank or hollow tree all day, and seeks food at night. Can it run fast on the ground? It feigns death when captured, and watches for a chance for stealthy escape.
The kangaroo (Fig. 362), like the opossum, gives birth to imperfectly developed young. (Kinship with what classes is thus indicated?) After birth, the young (about three fourths of an inch long) are carried in a ventral pouch and suckled for seven or eight months. They begin to reach down and nibble grass before leaving the pouch. Compare fore legs with hind legs, front half of body with
F . 362. G K .
hind half. Describe tail. What is it used for when kangaroo is at rest? In jumping, would it be useful for propelling and also for balancing the body? Describe hind and fore feet. Order ——. Why? ________. See key, page 193.
Imperfectly Toothed Mammals.
—These animals live chiefly in South America (sloth, armadillo, giant ant-eater) and Africa (pangolin). The sloth (Fig. 363) eats leaves. Its movements are remarkably slow, and a
vegetable growth resembling moss often gives its hair a green colour. (What advantage?) How many toes has it? How are its nails suited to its manner of living? Does it save exertion by hanging from the branches of trees instead of walking upon them?
F . 363. S of South America.
Judging from the figures (363, 364, 365), are the members of this order better suited for attack, active resistance, passive resistance, or concealment when contending with other animals? The ant-eater’s claws (Fig. 364) on the fore feet seem to be a hindrance in walking; for what are they useful? Why are its jaws so slender? What is
probably the use of the enormous bushy tail? The nine-banded armadillo (Fig. 365) lives in Mexico and Texas. It is omnivorous. To escape its enemies, it burrows into the ground with surprising rapidity. If unable to escape when pursued, its hard, stout tail and head are turned under to protect the lower side of the body where there are no scales. The three-banded species (Fig. 366) lives in Argentina. Compare the ears and tail of the two species; give
F . 364. G A - of South America. (See Fig. 354.) Find evidences that the edentates are a degenerate order. Describe another ant-eater (Fig. 360).
F . 365. N - A of Texas and Mexico. (Dasypus novemcinctus.) It is increasing in numbers; it is very useful, as it digs up and destroys insects. (See Fig. 347.)
reasons for differences. Why are the eyes so small? The claws so large? Order______. Why? ______.
F . 366. T - A (Tolypeutes tricinctus).
Insect Eaters.—The soft interior and crusty covering of insects makes it unnecessary for animals that prey upon them to have flattopped teeth for grinding them to powder, or long cusps for tearing them to pieces. The teeth of insect eaters, even the molars (Fig. 368), have many sharp tubercles, or points, for holding insects and piercing the crusty outer skeleton and reducing it to bits. As most insects dig in the ground or fly in the air, we are not surprised to learn that some insect-eating mammals (the bats) fly and others (the moles) burrow. Are the members of this order friends or competitors of man?
Why does the mole have very small eyes? Small ears? Compare the shape of the body of a mole and a rat. What difference? Why? Compare the front and the hind legs of a mole. Why are the hind legs so small and weak? Bearing in mind that the body must be arranged for digging and using narrow tunnels, study the skeleton (Fig. 368) in respect to the following: Bones of arm (length and shape), fingers, claws, shoulder bones, breastbone (why with ridge like a bird?), vertebræ (why are the first two so large?), skull (shape). There are no eye sockets, but there is a snout gristle; for the long, sensitive snout must serve in place of the small and almost useless eyes hidden deep in the fur. Is the fur sleek or rough? Why? Close or thin? It serves to keep the mole clean. The muscles of neck, breast, and shoulders are very strong. Why? The mole eats earthworms as well as insects. It injures plants by breaking and drying out their roots. Experiments
F . 367. T M .
F . 368. S M . (Shoulder blade is turned upward.)
show that the Western mole will eat moist grain, though it prefers insects. If a mole is caught, repeat the experiment, making a careful record of the food placed within its reach.
F . 369. S B .
As with the mole, the skeletal adaptations of the bat are most remarkable in the hand. How many fingers? (Fig. 369.) How many nails on the hand? Use of nail when at rest? When creeping? (Fig. 369.) Instead of feathers, the flying organs are made of a pair of extended folds of the skin supported by elongated bones, which form a framework like the ribs of an umbrella or a fan. How many digits are prolonged? Does the fold of the skin extend to the hind legs? The tail? Are the finger bones or the palm bones more prolonged to form the wing skeleton?
F . 370. V (Phyllostoma spectrum) of South America. × ⅙.
The skin of the wing is rich in blood vessels and nerves, and serves, by its sensitiveness to the slightest current of air, to guide the bat in the thickest darkness. Would you judge that the bat has sharp sight? Acute hearing?
The moles do not hibernate; the bats do. Give the reason for the difference. If bats are aroused out of a trance-like condition in winter, they may die of starvation. Why? The mother bat carries the young about with her, since, unlike birds, she has no nest. How are the young nourished? Order ________. Why? ________. (Key, p. 193.)
F . 371. P G (Geomys bursarius) × ¼, a large, burrowing field rat, with cheek pouches for carrying grain.
F . 372. Hind foot a, fore foot b, tail c, of B .
The Gnawing Mammals.
—These animals form the most numerous order of mammals. They lack canine teeth. Inference? The incisors are four in number in all species except the rabbits, which have six (see Fig. 345). They are readily recognized by their large incisors. These teeth grow throughout life, and if they are not constantly worn away by gnawing upon hard food, they become inconveniently long, and may prevent closing of the mouth and cause starvation. The hard enamel is all on the front surface, the dentine in the rear being softer; hence the incisors sharpen themselves by use to a chisel-like edge. The molars are set close together and have their upper surfaces level with each other. The ridges on them run crosswise so as to form a continuous
F . 373. B .
filelike surface for reducing the food still finer after it has been gnawed off (Fig. 345). The lower jaw fits into grooves in place of sockets. This allows the jaw to work back and forth instead of sidewise. The rabbits and some squirrels have a hare lip; i.e. the upper lip is split. What advantage is this in eating? In England the species that burrow are called rabbits; those that do not are called hares.
F . 374. P L R .
Name six enemies of rabbits. Why does a rabbit usually sit motionless unless approached very close? Do you usually see one before it dashes off? A rabbit has from three to five litters of from three to six young each year. Squirrels have fewer and smaller litters. Why must the rabbit multiply more rapidly than the squirrel in order to survive? English rabbits have increased in Australia until they are a plague. Sheep raising is interfered with by the loss of grass. The Australians now ship them to England in cold storage for food. Rabbits and most rodents lead a watchful, timid, and alert life. An exception is the porcupine, which, because of the defence of its barbed quills, is dull and sluggish.
The common rodents are:—
squirrels
rabbits
rats
mice
beavers
muskrats
porcupines
guinea pig
pouched gopher
prairie dog
prairie squirrel
chipmunk
ground hog
field mouse
Which of the above rodents are commercially important? Which are injurious to an important degree? Which have long tails? Why? Short tails? Why? Long ears? Why? Short ears? Why? Which are aquatic? Which dig or burrow? Which are largely nocturnal in habits? Which are arboreal? Which are protected by coloration? Which escape by running? By seeking holes?
Economic Importance.—Rabbits and squirrels destroy the eggs and young of birds. Are rabbits useful? Do they destroy useful food? The use of beaver and muskrat skins as furs will probably soon lead to their extinction. Millions of rabbits’ skins are used annually, the hair being made into felt hats. There are also millions of squirrel skins used in the fur trade. The hairs of the tail are made into fine paint brushes. The skins of common rats are used for the thumbs of kid gloves. Order ________. Why? ________.
Elephants.—Elephants, strange to say, have several noteworthy resemblances to rodents. Like them, elephants have no canine teeth; their molar teeth are few, and marked by transverse ridges and the incisors present are prominently developed (Figs. 376, 377). Instead of four incisors, however, they have only two, the enormous tusks, for there are no incisors in the lower jaw. Elephants and rodents both
F . 375. F S (Pteromys volucella). × ¼.
subsist upon plant food. Both have peaceful dispositions, but one order has found safety and ability to survive by attaining enormous size and strength; the other (e.g. rats, squirrels) has found safety in small size. Explain.
F . 376. H A E .
Suppose you were to observe an elephant for the first time, without knowing any of its habits. How would you know that it does not eat meat? That it does eat plant food? That it can defend itself? Why would you make the mistake of thinking that it is very clumsy and stupid? Why is its skin naked? Thick? Why must its legs be so straight? Why must it have either a very long neck or a substitute for one? (Fig. 376.) Are the eyes large or small? The ears? The brain cavity? What anatomical feature correlates with the long proboscis? Is the proboscis a new organ not found in other animals, or is it a specialization of one or more old ones? Reasons? What senses are especially active in the proboscis? How is it used in drinking? In grasping? What evidence that it is a development of the nose? The upper lip?
The tusks are of use in uprooting trees for their foliage and in digging soft roots for food. Can the elephant graze? Why, or why not? There is a finger-like projection on the end of the snout which is useful in delicate manipulations. The feet have pads to prevent jarring; the nails are short and hardly touch the ground. Order ________. Why? ________. Key, page 193.
Whales, Porpoises, Dolphins.—As the absurd mistake is sometimes made of confusing whales with fish, the pupil may compare them in the following respects: eggs, nourishment of young, fins, skin, eyes, size, breathing, temperature, skeleton (Figs. 209, 379, and 397).
F . 377. M T A E .
Porpoises and dolphins, which are smaller species of whales, live near the shore and eat fish. Explain the expression “blow like a porpoise.” They do not exceed five or eight feet in length, while the deep-sea whales are from thirty to seventy-five feet in length, being by far the largest animals in the world. The size of the elephant is limited by the weight that the bones and muscles support and move. The whale’s size is not so limited.
The whale bears one young (rarely twins) at a time. The mother carefully attends the young for a long time. The blubber, or thick layer of fat beneath the skin, serves to retain heat and to keep the body up to the usual temperature of mammals in spite of the cold water. It also serves, along with the immense lungs, to give lightness to the body. Why does a whale need large lungs? The tail of a whale is horizontal instead of vertical, that it may steer upward rapidly from the depths when needing to breathe. The teeth of some whales do not cut the gum, but are reabsorbed and are replaced by horny plates of “whalebone,” which act as strainers. Give evidence from the flippers, lungs, and other organs, that the whale is descended from a land mammal (Fig. 397). Compare the whale with a typical land mammal, as the dog, and enumerate the specializations of the whale for living in water. What change took place in the general form of the body? It is believed that on account of scarcity of food the land
F . 378. H G W (see Fig. 351).
ancestors of the whale, hundreds of thousands of years ago, took to living upon fish, etc., and, gradually becoming swimmers and divers, lost the power of locomotion on land. Order____. Why?____.
Elephants are rapidly becoming extinct because of the value of their ivory tusks. Whales also furnish valuable products, but they will probably exist much longer. Why?
The manatees and dugongs (sea cows) are a closely related order living upon water plants, and hence living close to shore and in the mouths of rivers. Order____. Why? ____.
Hoofed
Mammals.—All the animals in this order walk on the tips of their toes, which have been adapted to this use by the claws having developed into hoofs. The order is subdivided into the oddtoed (such as the horse with one toe and the rhinoceros with three) and the even-toed (as the ox with two toes and the pig with four). All the even-toed forms except the pig and hippopotamus chew the cud and are given the name of ruminants.
Horse and Man Compared.—To which finger and toe on man’s hand and foot does a horse’s foot correspond? (Figs. 381, 383, 399.) Has the horse kneecaps? Is its heel bone large or small? Is the fetlock on toe, instep, or ankle? Does the part of a horse’s hind leg that is most elongated correspond to the thigh, calf, or foot in man? On the fore leg, is the elongated part the upper arm, forearm, or hand? (Figs. 395, 399.) Does the most elongated part of the fore foot
F . 379. D .
F . 380. M , or sea cow; it lives near the shore and eats seaweed. (Florida to Brazil.)
F . 381. Left leg of man, left hind leg of dog and horse; homologous parts lettered alike.
correspond to the finger, the palm, or the wrist? (Fig. 382.) On the hind foot is it toe, instep, or ankle? Is the fore fetlock on the finger, the palm, or the wrist? (Figs. 382, 385, 399.) Is the hock at the toe, the instep, the heel, or the knee?
Specializations of the Mammals.
—The early mammals, of which the present marsupials are believed to be typical, had five toes provided with claws. They were not very rapid in motion nor dangerous in fight, and probably ate both animal and vegetable food.
According to the usual rule, they tended to increase faster than the food supply, and there were continual contests for food. Those whose claws and teeth were sharper drove the others from the food, or preyed upon them. Thus the specialization into the bold flesh eating beasts of prey and the timid vegetable feeders began. Which of the flesh eaters has already been studied at length? The insectivora escaped their enemies and found food by learning to burrow or fly. The rodents accomplished the same result either by acquiring great agility in climbing, or by living in holes, or by running. The proboscidians acquired enormous size and strength. The hoofed animals found safety in flight.
F . 382. S F M .
P, horse; D, dolphin; E, elephant; A, monkey; T, tiger; O, aurochs; F, sloth; M, mole.
Question: Explain how each is adapted to its specialized function.
F . 383. Feet of the ancestors of the horse.
F . 384. T S A (Tapirus americanus). × ¹₂₅.
Questions: How does it resemble an elephant? (Fig. 376.) A horse? (p. 210.)
F . 385. H , descended from a small wild species still found in Western Asia.
Ungulates, as the horse, need no other protection than their great speed, which is due to lengthening the bones of the legs and rising upon the very tip of the largest toe, which, to support the weight, developed an enormous toenail called a hoof. The cattle, not having developed such speed as the horse, usually have horns for defence. If a calf or cow bellows with distress, all the cattle in the neighbourhood rush to the rescue. This unselfish instinct to help others was an aid to the survival of wild cattle living in regions infested with beasts of prey. Which of Æsop’s fables is based upon this instinct? The habit of
rapid grazing and the correlated habit of chewing the cud were also of great value, as it enabled cattle to obtain grass hurriedly and to retire to a safe place to chew it. Rudiments of the upper incisors are present in the jaw of the calf, showing the descent from animals which had a complete set of teeth. The rudiments are absorbed and the upper jaw of the cow lacks incisors entirely, as they would be useless because of the cow’s habit of seizing the grass with her rough tongue and cutting it with the lower incisors as the head is jerked forward. This is a more rapid way of eating than by biting. Which leaves the grass shorter after grazing, a cow or a horse? Why? Grass is very slow of digestion, and the ungulates have an alimentary canal twenty to thirty times the length of the body. Thorough chewing is necessary for such coarse food, and the ungulates which chew the cud (ruminants) are able, by leisurely and thorough chewing, to make the best use of the woody fibre (cellulose) which is the chief substance in their food.
F . 386. S C . Compare with horse (Fig. 395) as to legs, toes, tail, mane, dewlap, ears, body.
Ruminants have four divisions to the stomach. Their food is first swallowed into the roomy paunch in which, as in the crop of a bird, the bulky food is temporarily stored. It is not digested at all in the paunch, but after being moistened, portions of it pass successively into the honeycomb, which forms it into balls to be belched up and ground by the large molars as the animal lies with eyes half closed under the shade of a tree. It is then swallowed a second time and is acted upon in the third division (or manyplies) and the fourth division (or reed). Next it passes into the intestine. Why is the paunch the largest compartment? In the figure do you recognize the paunch by its size? The honeycomb by its lining? Why is it round? The last two of the four divisions may be known by their direct connection with the intestine.
F . 387. Food traced through stomachs of cow. (Follow arrows.)
F . 388. Section of cow ’ s stomachs. Identify each. (See text.)
F . 389. O . This will probably prove to be the last large mammal to be discovered by civilized man. It was found in the forests of the Kongo in 1900.
The true gastric juice is secreted only in the fourth stomach. Since the cud or unchewed food is belched up in balls from the round “honeycomb,” and since a ball of hair is sometimes found in the stomach of ruminants, some ignorant people make the absurd mistake of calling the ball of hair the cud. This ball accumulates in the paunch because of the friendly custom cows have of combing each other’s hair with their rough tongues, the hair sometimes being swallowed. Explain the saying that if a cow stops chewing the cud she will die.
Questions: It shows affinities (find them) with giraffe, deer, and zebra. It is a ruminant ungulate (explain meaning see text).
).
Does a cow’s lower jaw move sidewise or back and forth? Do the ridges on the molars run sidewise or lengthwise? Is a cow’s horn hollow? Does it have a bony core? (Fig. 344.)
The permanent hollow horns of the cow and the solid deciduous horns of the deer are typical of the two kinds of horns possessed by ruminants. The pronghorned antelope (Fig. 391) of the United States, however, is an intermediate form, as its horns are hollow, but are shed each year. The hollow horns are a modification of
F . 391. P - A (Antelocarpa Americana).
F . 390. A C (Camelus dromedarius
hair. Do solid or hollow horns branch? Which are possessed by both sexes? Which are pointed? Which are better suited for fighting? Why would the deer have less need to fight than the cattle? Deer are polygamous, and the males use their horns mostly for fighting one another. The sharp hoofs of deer are also dangerous weapons. The white-tail deer (probably the same species as the Virginian red deer) is the most widely distributed of the American deer. It keeps to the lowlands, while the black-tailed deer prefers a hilly country. The moose, like the deer, browses on twigs and leaves. The elk, like cattle, eats grass.
The native sheep of America is the big horn, or Rocky Mountain sheep (Fig. 392). The belief is false that they alight upon their horns when jumping down precipices. They post sentinels and are very wary. There is also a native goat, a white species, living high on the Rocky Mountains near the snow. They are rather stupid animals. The
F . 392. R M S (Ovis montana). × ¹⁄₂₄.
bison once roamed in herds of countless thousands, but, with the exception of a few protected in parks, it is now extinct. Its shaggy hide was useful to man in winter, so it has been well-nigh destroyed. For gain man is led to exterminate elephants, seals, rodents, armadillos, whales, birds, deer, mussels, lobsters, forests, etc.
F . 393. P (Dicotyles torquatus) of Texas and Mexico. × ¹₁₂.
Our only native hog is the peccary, found in Texas (Fig. 393). In contrast with the heavy domestic hog, it is slender and active. It is fearless, and its great tusks are dangerous weapons. The swine are the only ungulates that are not strictly vegetable feeders. The habit of fattening in summer was useful to wild hogs, since snow hid most of their food in winter. The habit has been preserved under domestication. Are the small toes of the hog useless? Are the “dew claws” of cattle useless? Will they probably become larger or smaller? Order?
Illustrated Study of Vertebrate Skeletons: Taking man ’ s skeleton as complete, which of these seven skeletons is most incomplete?
Regarding the fish skeleton as the original vertebrate skeleton, how has it been modified for (1) walking, (2) walking on two legs, (3) flying?
Which skeleton is probably a degenerate reversion to original type? (p. 209.)
How is the horse specialized for speed?
F . 394. B .
Which is more specialized, the foot of a man or that of a chimpanzee? Is the foot of a man or that of a chimpanzee better suited for supporting weight? How does its construction fit it for this?
Which has a better hand, a man or a chimpanzee? What is the difference in their arms? Does difference in structure correspond to difference in use?
Which of the seven skeletons bears the most complex breastbone?
Which skeleton bears no neck (or cervical) vertebræ? Which bears only one?
Do all have tail vertebræ, or vertebræ beyond the hip bones? Does each have shoulder blades?
Compare (1) fore limbs, (2) hind limbs, (3) jaws of the seven skeletons. Which has relatively the shortest jaws? Why? What seems to be the typical number of ribs? limbs? digits?
Does flipper of a dolphin have same bones as arm of a man?
How many thumbs has a chimpanzee?
Are all the classes of vertebrates represented in this chart? (p. 125.)
