Six big events of human evolution

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 Selec