P1: 000 GGBD138FM GR3673/Dunsworth Human Origins 101 July 12, 2007 16:32 P1: 000 GGBD138FM GR3673/Dunsworth Recent Titles in the Science 101 Series Evolution 101 Janice Moore and Randy Moore Biotechnology 101 Brian Robert Shmaefsky Cosmology 101 Kristine M Larsen Genetics 101 Michael Windelspecht July 12, 2007 16:32 P1: 000 GGBD138FM GR3673/Dunsworth July 12, 2007 Human Origins 101 Holly M Dunsworth Science 101 GREENWOOD PRESS Westport, Connecticut r London 16:32 P1: 000 GGBD138FM GR3673/Dunsworth Library of Congress Cataloging-in-Publication Data Dunsworth, Holly M Human origins 101 / Holly M Dunsworth p cm — (Science 101, ISSN 1931-3950) Includes bibliographical references and index ISBN 978–0–313–33673–7 (alk paper) Human beings—Origin Human evolution I Title GN281.D865 2007 599.93 8—dc22 2007022747 British Library Cataloguing in Publication Data is available Copyright c 2007 by Holly M Dunsworth All rights reserved No portion of this book may be reproduced, by any process or technique, without the express written consent of the publisher Library of Congress Catalog Card Number: 2007022747 ISBN-13: 978–0–313–33673–7 ISSN: 1931-3950 First published in 2007 Greenwood Press, 88 Post Road West, Westport, CT 06881 An imprint of Greenwood Publishing Group, Inc www.greenwood.com Printed in the United States of America The paper used in this book complies with the Permanent Paper Standard issued by the National Information Standards Organization (Z39.48–1984) 10 July 12, 2007 16:32 P1: 000 GGBD138FM GR3673/Dunsworth July 12, 2007 For Mom and Dad, Model Human Beings 16:32 P1: 000 GGBD138FM GR3673/Dunsworth July 12, 2007 16:32 P1: 000 GGBD138FM GR3673/Dunsworth July 12, 2007 Contents Series Foreword Preface Acknowledgments Introduction xi xiii xvii xix A Brief Overview of the Search for Human Origins The Science of Human Origins and Evolution Scientific Method Forefathers Piltdown Dubois and Beyond Current Issues 1 10 13 From Fish to Fishermen Evidence for Evolution Biogeography Fossils and Geology Artificial Selection Homology and Analogy Vestigial Traits Embryology Natural Selection Variation Heredity Differential Fitness Adaptation From Mendel to the Modern Synthesis DNA, Chromosomes, Cells, and Inheritance 17 17 18 19 19 19 21 21 22 23 23 24 24 25 27 16:32 P1: 000 GGBD138FM viii GR3673/Dunsworth July 12, 2007 Contents Forces of Evolution Mutation Gene Flow Genetic Drift Selection Sexual Selection Speciation Clarifying Evolution Taxonomy and Classification Primates Monkeys and Apes 30 30 31 31 31 32 34 37 38 41 44 Prehistoric Evidence What Is a Fossil? Geology and Dating Methods Climate Change and Paleoenvironment The Earliest Primates and Fossil Monkeys Fossil Apes Bushes and Trees The Last Common Ancestor Quadrupedal to Bipedal The Earliest Hominins Sahelanthropus Orrorin Ardipithecus Australopiths Australopithecus anamensis Australopithecus afarensis Australopithecus africanus Australopithecus garhi Paranthropus (Robust Australopiths) The Human Genus Homo erectus Archaic Homo Sapiens Neanderthals Stone Tools Anatomically Modern Humans Homo Floresiensis 47 47 50 54 55 57 61 62 64 65 67 69 69 70 72 73 75 77 78 80 82 86 88 90 93 95 Modern Evidence Molecular Clocks Humans and Chimpanzees: The Narrow Divide 97 97 99 16:32 P1: 000 GGBD138FM GR3673/Dunsworth July 12, 2007 Contents Mitochondrial Eve and Y-Chromosome Adam Human Adaptation Sickle Cell Trait Lactose Tolerance Skin Color Ancient DNA and the Neanderthal Genome 102 105 106 106 107 109 Interpreting the Evidence Big Brains and Intelligence Evolutionary Psychology Bipedalism Reduced Body Hair Body Size, Shape, and Strength Teeth Tool Use Diet Scavenging and Hunting Fire Reproduction Language Human Revolution Altruism and the Human Colony War or Peace? 113 113 117 118 122 124 126 128 131 133 136 137 140 143 146 148 Beyond Human Origins Multiregional and Out of Africa Models Worldwide Dispersal Will We Evolve or Will We Go Extinct? Deep Impact Rewinding and Replaying Evolution 151 151 155 158 160 162 Appendix A: Human and Chimpanzee Skeletal Anatomy Appendix B: Geologic Time Scale Appendix C: Recommended Resources Glossary Selected Bibliography Index 165 167 169 171 179 185 16:32 ix P1: 000 GGBD138FM GR3673/Dunsworth July 12, 2007 16:32 ... Holly M Human origins 101 / Holly M Dunsworth p cm — (Science 101, ISSN 1931-3950) Includes bibliographical references and index ISBN 978–0–313–33673–7 (alk paper) Human beings—Origin Human evolution... your own quest for human origins Chapter begins the book with a brief history of the search for human origins and human evolutionary studies As a consequence of selfconsciousness, humans have probably... emigrated to America on a boat from Ireland It is my hope that readers of Human Origins 101 take away this important tenet of human origins studies: we are modified African apes that, despite seemingly