Kud lesson plan

ESSENTIALS OF PHYSICAL ANTHROPOLOGY

Bn W. W. NORTON & COMPANY NEW YORK • LONDON

ESSENTIALS OF PHYSICAL ANTHROPOLOGY D I S C O V E R I N G O U R O R I G I N S

CLARK SPENCER LARSEN T H E O H I O S T A T E U N I V E R S I T Y

T H I R D E D I T I O N

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Library of Congress Cataloging- in- Publication Data

Larsen, Clark Spencer. Essentials of physical anthropology : discovering our origins / Clark Spencer Larsen, The Ohio State University.—Third edition. pages cm Includes index. ISBN 978-0-393-93866-1 (pbk.) 1. Physical anthropology. I. Title. GN50.4.L367 2015 599.9—dc23 2015023645

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TO CHRIS AND SPENCER, WITH MY DEEPEST THANKS FOR THEIR HELP, ENCOURAGEMENT, AND

(UNWAVERING) PATIENCE

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CLARK SPENCER LARSEN heads the Department of Anthropology at The Ohio State University, Columbus. A native of Nebraska, he received his B.A. from Kansas State University and M.A. and Ph.D. from the Uni- versity of Michigan. Clark’s research is in bioarchaeology, skeletal biol- ogy, and paleoanthropology. He has worked in North America, Europe, and Asia. He has taught at the University of Massachusetts, Northern Illi- nois University, Purdue University, and the University of North Carolina. Since 2001, he has been a member of the faculty at Ohio State, where he is Distinguished Professor of Social and Behavioral Sciences. He teaches introductory physical anthropology, osteology, bioarchaeology, and paleoanthropology. Clark has served as president of the American Association of Physical Anthropologists and as editor- in- chief of the American Journal of Physical Anthropology. In addition to Our Origins, he has authored or edited 30 books and monographs, including Bioar- chaeology: Interpreting Behavior from the Human Skeleton, Skeletons in Our Closet, Advances in Dental Anthropology, and A Companion to Biological Anthropology.

ABOUT THE AUTHOR

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To the Instructor xx To the Student xxviii

CHAPTER 1 What Is Physical Anthropology? 2

PART I The Present: Foundation for the Past 19

CHAPTER 2 Evolution: Constructing a Fundamental Scientific Theory 20

CHAPTER 3 Genetics: Reproducing Life and Producing Variation 42

CHAPTER 4 Genes and Their Evolution: Population Genetics 70

CHAPTER 5 Biology in the Present: Living People 100

CHAPTER 6 Biology in the Present: The Other Living Primates 132

CHAPTER 7 Primate Sociality, Social Behavior, and Culture 164

PART II The Past: Evidence for the Present 183

CHAPTER 8 Fossils and Their Place in Time and Nature 184

CHAPTER 9 Primate Origins and Evolution: The First 50 Million Years 216

CHAPTER 10 Early Hominin Origins and Evolution: The Roots of Humanity 244

CHAPTER 11 The Origins and Evolution of Early Homo 282

CHAPTER 12 The Origins, Evolution, and Dispersal of Modern People 306

CHAPTER 13 Our Last 10,000 Years: Agriculture, Population, Biology 350

BASIC TABLE OF CONTENTS

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TABLE OF CONTENTS

Two-Page Spreads xix

To the Instructor xx

Tools for Teaching and Learning xxiii

Who Helped xxv

To the Student xxviii

CHAPTER 1 WHAT IS PHYSICAL ANTHROPOLOGY? 2

Big Questions 3 What Is Anthropology? 5 What Is Physical Anthropology? 7

What Do Physical Anthropologists Do? 7 What Makes Humans So Different from Other Animals?: The Six Steps to

Humanness 8 How We Know What We Know: The Scientific Method 14 Answering the Big Questions 16 Key Terms 17 Evolution Review 17 Additional Readings 17

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x Table of Contentsx Table of Contents

PART I THE PRESENT: FOUNDATION FOR THE PAST 19

CHAPTER 2 EVOLUTION: CONSTRUCTING A FUNDAMENTAL SCIENTIFIC THEORY 20

Big Questions 21 The Theory of Evolution: The Context for Darwin 23

Geology: Reconstructing Earth’s Dynamic History 24 Paleontology: Reconstructing the History of Life on Earth 25 Taxonomy and Systematics: Classifying Living Organisms and Identifying Their

Biological Relationships 26 Concept Check Pre-Darwinian Theory and Ideas: Groundwork for

Evolution 27 Demography: Influences on Population Size and Competition for Limited

Resources 28 Evolutionary Biology: Explaining the Transformation of Earlier Life-Forms into

Later Life-Forms 28 Concept Check Darwin Borrows from Malthus 30 The Theory of Evolution: Darwin’s Contribution 31 Since Darwin: Mechanisms of Inheritance, the Evolutionary Synthesis, and the

Discovery of DNA 33 Mechanisms of Inheritance 33 The Evolutionary Synthesis, the Study of Populations, and the Causes of

Evolution 36 DNA: Discovery of the Molecular Basis of Evolution 37

Answering the Big Questions 39 Key Terms 39 Evolution Review: Past, Present, and Future of a Fundamental Scientific

Theory 40 Additional Readings 41

CHAPTER 3 GENETICS: REPRODUCING LIFE AND PRODUCING VARIATION 42

Big Questions 43 The Cell: Its Role in Reproducing Life and Producing Variation 44 The DNA Molecule: The Genetic Code 46

DNA: The Blueprint of Life 48 The DNA Molecule: Replicating the Code 48 How Do We Know? Ancient DNA Opens New Windows on the Past 50 Concept Check The Two Steps of DNA Replication 51

Chromosome Types 51 Mitosis: Production of Identical Somatic Cells 52 Meiosis: Production of Gametes (Sex Cells) 54 Producing Proteins: The Other Function of DNA 56

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Concept Check The Two Steps of Protein Synthesis 60 Genes: Structural and Regulatory 61 Polymorphisms: Variations in Specific Genes 61

Genotypes and Phenotypes: Genes and Their Expression 63 The Complexity of Genetics 65 Answering the Big Questions 67 Key Terms 68 Evolution Review: Insights from Genetics 68 Additional Readings 69

CHAPTER 4 GENES AND THEIR EVOLUTION: POPULATION GENETICS 70

Big Questions 71 Demes, Reproductive Isolation, and Species 72 Hardy-Weinberg Law: Testing the Conditions of Genetic Equilibrium 76 Mutation: The Only Source of New Alleles 77 Natural Selection: Advantageous Characteristics, Survival, and

Reproduction 80 Patterns of Natural Selection 81 Natural Selection in Animals: The Case of the Peppered Moth and Industrial

Melanism 82 Natural Selection in Humans: Abnormal Hemoglobins and Resistance to

Malaria 84 The Geography of Sickle-Cell Anemia and the Association with Malaria 86 The Biology of Sickle-Cell Anemia and Malarial Infection 87 The History of Sickle-Cell Anemia and Malaria 87 Other Hemoglobin and Enzyme Abnormalities 89

Genetic Drift: Genetic Change due to Chance 90 Founder Effect: A Special Kind of Genetic Drift 93

Gene Flow: Spread of Genes across Population Boundaries 93 Concept Check What Causes Evolution? 97 Answering the Big Questions 97 Key Terms 98 Evolution Review: The Four Forces of Evolution 99 Additional Readings 99

CHAPTER 5 BIOLOGY IN THE PRESENT: LIVING PEOPLE 100

Big Questions 101 Is Race a Valid, Biologically Meaningful Concept? 102

Brief History of the Race Concept 102 Debunking the Race Concept: Franz Boas Shows that Human Biology Is Not

Static 103

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So-Called Racial Traits Are Not Concordant 103 Human Variation: Geographic Clines, Not Racial Categories 103

Life History: Growth and Development 104 The Growth Cycle: Conception through Adulthood 105 Prenatal Stage: Sensitive to Environmental Stress, Predictive of Adult Health

105 Postnatal Stage: The Maturing Brain, Preparing for Adulthood 106 Adult Stage: Aging and Senescence 109 Evolution of Human Life History: Food, Sex, and Strategies for Survival and

Reproduction 111 Concept Check Life History Stages in Humans: Prenatal, Postnatal, and

Adult 111 Prolonged Childhood: Fat-Bodied Moms and Their Big-Brained Babies 112 Grandmothering: Part of Human Adaptive Success 112

Adaptation: Meeting the Challenges of Living 113 Climate Adaptation: Living on the Margins 114

Heat Stress and Thermoregulation 114 Body Shape and Adaptation to Heat Stress 114 Cold Stress and Thermoregulation 115 Solar Radiation and Skin Color 116 Solar Radiation and Vitamin D Synthesis 117 Solar Radiation and Folate Protection 118 High Altitude and Access to Oxygen 118

Concept Check Adaptation: Heat, Cold, Solar Radiation, High Altitude 119 Nutritional Adaptation: Energy, Nutrients, and Function 120

Macronutrients and Micronutrients 120 Human Nutrition Today 121 Overnutrition and the Consequences of Dietary Excess 123

Concept Check Nutritional Adaptation 126 Workload Adaptation: Skeletal Homeostasis and Function 126 Excessive Activity and Reproductive Ecology 128

Answering the Big Questions 129 Key Terms 130 Evolution Review: Human Variation Today 130 Additional Readings 131

CHAPTER 6 BIOLOGY IN THE PRESENT: THE OTHER LIVING PRIMATES 132

Big Questions 133 What Is a Primate? 135

Arboreal Adaptation—Primates Live in Trees and Are Good at It 138 Primates Have a Versatile Skeletal Structure 138 Primates Have an Enhanced Sense of Touch 140

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Primates Have an Enhanced Sense of Vision 141 Primates Have a Reduced Reliance on Senses of Smell and Hearing 141

Concept Check What Makes Primates Good at Living in Trees? 142 Dietary Plasticity—Primates Eat a Highly Varied Diet, and Their Teeth Reflect This

Adaptive Versatility 142 Primates Have Retained Primitive Characteristics in Their Teeth 142 Primates Have a Reduced Number of Teeth 142 Primates Have Evolved Different Dental Specializations and Functional

Emphases 143 Concept Check What Gives Primates Their Dietary Flexibility? 143

Parental Investment—Primate Parents Provide Prolonged Care for Fewer but Smarter, More Socially Complex, and Longer-Lived Offspring 146

Concept Check Primate Parenting 148 What Are the Kinds of Primates? 148

The Strepsirhines 153 Concept Check Monkey or Ape? Differences Matter 154

The Haplorhines 155 Concept Check Strepsirhines and Haplorhines Differ in Their Anatomy and

Senses 161 Answering the Big Questions 162 Key Terms 162 Evolution Review: Our Closest Living Relatives 163 Additional Readings 163

CHAPTER 7 PRIMATE SOCIALITY, SOCIAL BEHAVIOR, AND CULTURE 164

Big Questions 165 Primate Societies: Diverse, Complex, Long-Lasting 166

Diversity of Primate Societies 166 Primate Social Behavior: Enhancing Survival and Reproduction 167 Primate Residence Patterns 168 Primate Reproductive Strategies: Males’ Differ from Females’ 169

Concept Check Male and Female Reproductive Strategies 170 The Other Side of Competition: Cooperation in Primates 170

Getting Food: Everybody Needs It, but the Burden Is on Mom 172 Acquiring Resources and Transmitting Knowledge: Got Culture? 173 Vocal Communication Is Fundamental Behavior in Primate Societies 175 Answering the Big Questions 181 Key Terms 181 Evolution Review: Primate Social Organization and Behavior 182 Additional Readings 182

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PART II THE PAST: EVIDENCE FOR THE PRESENT 183

CHAPTER 8 FOSSILS AND THEIR PLACE IN TIME AND NATURE 184

Big Questions 185 Fossils: Memories of the Biological Past 188

What Are Fossils? 188 Taphonomy and Fossilization 188 Types of Fossils 188 Limitations of the Fossil Record: Representation Is Important 191

Just How Old Is the Past? 192 Time in Perspective 192 Geologic Time: Earth History 193 Relative and Numerical Age 195 Relative Methods of Dating: Which Is Older, Younger, the Same Age? 196

Stratigraphic Correlation 196 Chemical Dating 196 Biostratigraphic (Faunal) Dating 197 Cultural Dating 198

Absolute Methods of Dating: What Is the Numerical Age? 198 The Radiometric Revolution and the Dating Clock 198 The Revolution Continues: Radiopotassium Dating 203 Non-Radiometric Absolute Dating Methods 205

Genetic Dating: The Molecular Clock 207 Concept Check How Old Is It? 208 Reconstruction of Ancient Environments and Landscapes 209

The Driving Force in Shaping Environment: Temperature 210 Chemistry of Animal Remains and Ancient Soils: Windows onto Diets and

Habitats 211 Answering the Big Questions 213 Key Terms 214 Evolution Review: The Fossil Record 214 Additional Readings 215

CHAPTER 9 PRIMATE ORIGINS AND EVOLUTION: THE FIRST 50 MILLION YEARS 216

Big Questions 217 Why Did Primates Emerge? 218 The First True Primate: Visual, Tree-Dwelling, Agile, Smart 220

Primates in the Paleocene? 220 Eocene Euprimates: The First True Primates 220 The Anthropoid Ancestor: Euprimate Contenders 224 The First Anthropoids 225

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Early Anthropoids Evolve and Thrive 227 Concept Check When Were They Primates?: Anatomy through Time 227 Coming to America: Origin of New World Higher Primates 230

How Anthropoids Got to South America 230 Apes Begin in Africa and Dominate the Miocene Primate World 231 Apes Leave Africa: On to New Habitats and New Adaptations 234

Apes in Europe: The Dryopithecids 234 Apes in Asia: The Sivapithecids 235 Dead End in Ape Evolution: The Oreopithecids 235 Climate Shifts and Habitat Changes 238 Miocene Ape Survivors Give Rise to Modern Apes 238

Apes Return to Africa? 238 Concept Check The First Apes: A Remarkable Radiation 239 Monkeys on the Move 239 Answering the Big Questions 241 Key Terms 242 Evolution Review: Primate Social Organization and Behavior:

The Deep Roots of the Order Primates 242 Additional Readings 243

CHAPTER 10 EARLY HOMININ ORIGINS AND EVOLUTION: THE ROOTS OF HUMANITY 244

Big Questions 245 What Is a Hominin? 246

Bipedal Locomotion: Getting Around on Two Feet 248 Nonhoning Chewing: No Slicing, Mainly Grinding 248

Why Did Hominins Emerge? 251 Charles Darwin’s Hunting Hypothesis 251

Concept Check What Makes a Hominin a Hominin? 252 Peter Rodman and Henry McHenry’s Patchy Forest Hypothesis 254 Owen Lovejoy’s Provisioning Hypothesis 254 Sexual Dimorphism and Human Behavior 255 Bipedality Had Its Benefits and Costs: An Evolutionary Trade-Off 255

What Were the First Hominins? 256 The Pre-Australopithecines 256

Sahelanthropus tchadensis (7–6 mya) 257 Orrorin tugenensis (6 mya) 257 Ardipithecus kadabba and Ardipithecus ramidus (5.8–4.4 mya) 258

Concept Check The Pre-Australopithecines 263 The Australopithecines (4–1 mya) 264

Australopithecus anamensis (4 mya) 265 Australopithecus afarensis (3.6–3.0 mya) 266 Australopithecus (Kenyanthropus) platyops (3.5 mya) 269

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Diversification of the Homininae: Emergence of Multiple Evolutionary Lineages from One (3–1 mya) 269

Australopithecus garhi (2.5 mya) 270 The First Tool Makers and Users: Australopithecus or Homo? 270

Evolution and Extinction of the Australopithecines 273 Concept Check The Australopithecines 276 Answering the Big Questions 280 Key Terms 280 Evolution Review: The First Hominins 281 Additional Readings 281

CHAPTER 11 THE ORIGINS AND EVOLUTION OF EARLY HOMO 282

Big Questions 283 Homo habilis: The First Species of the Genus Homo 285

The Path to Humanness: Bigger Brains, Tool Use, and Adaptive Flexibility 285

Homo habilis and Australopithecus: Similar in Body Plan 287 Homo habilis’s Adaptation: Intelligence and Tool Use Become Important 287 Habitat Changes and Increasing Adaptive Flexibility 288

Concept Check Homo habilis: The First Member of Our Lineage 288 Homo erectus: Early Homo Goes Global 289

Homo erectus in Africa (1.8–.3 mya) 290 Homo erectus in Asia (1.8–.3 mya) 293 Homo erectus in Europe (1.2 million–400,000 yBP) 296 Evolution of Homo erectus: Biological Change, Adaptation, and Improved

Nutrition 297 Patterns of Evolution in Homo erectus 302

Concept Check Homo erectus: Beginning Globalization 303 Answering the Big Questions 304 Key Terms 305 Evolution Review: The Origins of Homo 305 Additional Readings 305

CHAPTER 12 THE ORIGINS, EVOLUTION, AND DISPERSAL OF MODERN PEOPLE 306

Big Questions 307 What Is So Modern about Modern Humans? 309 Modern Homo sapiens: Single Origin and Global Dispersal or Regional

Continuity? 309 What Do Homo sapiens Fossils Tell Us about Modern Human Origins? 311

Early Archaic Homo sapiens 311 Archaic Homo sapiens in Africa (350,000–200,000 yBP) 312

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Early Archaic Homo sapiens in Asia (350,000–130,000 yBP) 312 Early Archaic Homo sapiens in Europe (500,000–130,000 yBP) 313 Early Archaic Homo sapiens’ Dietary Adaptations 313

Late Archaic Homo sapiens 314 Late Archaic Homo sapiens in Asia (60,000–40,000 yBP) 315 Late Archaic Homo sapiens in Europe (130,000–30,000 yBP) 316 The Neandertal Body Plan: Aberrant or Adapted? 319 Neandertal Hunting: Inefficient or Successful? 321 Neandertals Buried Their Dead 324 Neandertals Talked 325 Neandertals Used Symbols 327

Early Modern Homo sapiens 327 Concept Check Archaic Homo sapiens 328

Early Modern Homo sapiens in Africa (200,000–6,000 yBP) 329 Early Modern Homo sapiens in Asia (90,000–18,000 yBP) 331 Early Modern Homo sapiens in Europe (35,000–15,000 yBP) 332

Modern Behavioral and Cultural Transitions 334 How Has the Biological Variation in Fossil Homo sapiens Been

Interpreted? 335 Ancient DNA: Interbreeding between Neandertals and Early Modern People? 336

Concept Check Early Modern Homo sapiens 337 Living People’s Genetic Record: Settling the Debate on Modern Human Origins 338

Assimilation Model for Modern Human Variation: Neandertals Are Still with Us 339

Concept Check Models for Explaining Modern Homo sapiens’ Origins 340 Modern Humans’ Other Migrations: Colonization of Australia, the Pacific, and

the Americas 340 Down Under and Beyond: The Australian and Pacific Migrations 342 Arrival in the Western Hemisphere: The First Americans 344

Answering the Big Questions 348 Key Terms 349 Evolution Review: The Origins of Modern People 349 Additional Readings 349

CHAPTER 13 OUR LAST 10,000 YEARS: AGRICULTURE, POPULATION, BIOLOGY 350

Big Questions 351 The Agricultural Revolution: New Foods and New Adaptations 353

Population Pressure 354 Regional Variation 355 Survival and Growth 359

Agriculture: An Adaptive Trade-Off 360 Population Growth 360 Environmental Degradation 361

Concept Check The Good and Bad of Agriculture 362

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How Did Agriculture Affect Human Biology? 362 The Changing Face of Humanity 363

Two Hypotheses 363 Implications for Teeth 365

Concept Check Soft Food and Biological Change 365 Building a New Physique: Agriculture’s Changes to Workload/Activity 366 Health and the Agricultural Revolution 369

Population Crowding and Infectious Disease 369 Concept Check Labor, Lifestyle, and Adaptation in the Skeleton 370

The Consequences of Declining Nutrition: Tooth Decay 371 Nutritional Consequences Due to Missing Nutrients: Reduced Growth and

Abnormal Development 371 Nutritional Consequences of Iron Deficiency 373

Concept Check Health Costs of Agriculture 374 Nutritional Consequences: Heights on the Decline 375

If It Is So Bad for You, Why Farm? 375 The Past Is Our Future 375 Our Ongoing Evolution 376 Answering the Big Questions 378 Key Terms 379 Evolution Review: Setting the Stage for the Present and Future 379 Additional Readings 380

Appendix: The Skeleton A1

Glossary A11

Glossary of Place Names A19

Bibliography A21

Permissions Acknowledgments A47

Index A51

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T WO- PAGE SPRE ADS

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ENHANCED TOUCH

Primates have an enhanced sense of touch. This sensitivity is due in part to the presence of dermal ridges (fingerprints and toe prints) on the inside surfaces of the hands and feet. The potto, a prosimian, has primitive dermal ridges, whereas the human, a higher primate, has more derived ridges, which provide better gripping ability.

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M ai

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GENERALIZED SKELETAL STRUCTURE

Primates have a generalized skeletal structure. The bones that make up the shoulders, upper limbs, lower limbs, and other major joints such as the hands and feet are separate, giving primates a great deal of flexibility when moving in trees. In this monkey skeleton, note the grasping hands and feet, the long tail, and the equal length of the front and hind limbs relative to each other.

REDUCED SMELL

Primates have a reduced sense of smell. The smaller and less projecting snouts of most primates indicate their decreased reliance on smell.

DIETARY VERSATILITY

Primates have dietary plasticity. Part of the record of primate dietary adaptation is found in the teeth. The red colobus monkey dentition shown here is typical of a catarrhine dentition with a 2/1/2/3 dental formula. Note the differences in morphology of the four different tooth types: incisors (I1, I2), canines (C), premolars (P3, P4), and molars (M1, M2, M3).

ENHANCED VISION

Primates have an enhanced sense of vision. Evolution has given primates better vision, including increased depth perception and seeing in color. The eyes’ convergence provides significant overlap in the visual fields and thus greater sense of depth.

Human Potto

Overlapping visual fields

Taï Forest

MonkeyDog

Reduced snout length

I1 I2I2

CC

P3P3 P4P4 M1

M2

M3

M1

M2

M3

I1I1 I2I2 CC

P3P3

P4P4

M1

M2

M3

M1

M2

M3

Black-and-white colobus

Campbell’s

Chimpanzee

Demidoff’s galago

Diana monkey

Human

Lesser spot-nosed

Olive colobus

Potto

Putty-nosed

Red colobus

Sooty mangabey

Thomas’s galago

Eagle

F I G U R E

6.2 Primate Adaptation in Microcosm: The Taï Forest, Ivory Coast, West Africa

Apes Leave Africa: On to New Habitats and New Adaptations | 237236 | CHAPTER 9 Primate Origins and Evolution: The First 50 Million Years

Primate evolution began with primitive primates in the Eocene, setting the stage for the origin of all hominoids. Euprimates of the Eocene had the basic characteristics of living primates, such as convergent eye orbits and grasping digits. In the last 20 million years, primates diversified in appearance and behavior. These changes included the shift, for some, from life in the trees to life on the ground, and eventually the beginning of bipedality in the late miocene. (Based on Fleagle, J. G. Primate Adaptation and Evolution, 2nd ed. 1999. Academic Press.)

Scenes from the late Eocene in the Paris Basin. Top: The diurnal Adapis is feeding on leaves. Bottom: Several taxa of omomyids (Pseudoloris, Necrolemur, Microchoerus). Note the large eyes, a nocturnal adaptation, typical of both ancient and modern prosimians who are active at night.

Scene from the early Miocene of Rusinga Island, Kenya. Apes first appeared during this period, and these are the first apes (two species of Proconsul, Dendropithecus, Limnopithecus). These and other taxa form the ancestry of all later apes and hominins. Note the range of habitats occupied by these primates within the forest, including some in the middle and lower canopies and some on the forest floor. These primates show a combination of monkeylike and apelike features, in the skeleton and skull, respectively.

Scenes from the early Oligocene of the Fayum, Egypt. These anthropoid ancestors include Aegyptopithecus, Propliopithecus, and Apidium. These primates were adept arborealists, using their hands and feet for climbing and feeding.