Shadows of Forgotten Ancestors

This book addresses the deep past, the most formative steps in our origins. Later, we will gather up the threads laid down here. We have been led to the writings of those who preceded us in this search, to distant epochs and other worlds and across a multitude of disciplines. We tried to keep in mind the physicist Niels Bohr’s aphorism, “Clarity through breadth.” The breadth required can be a little daunting, though. Humans have erected high walls separating the branches of knowledge essential to this quest—the various sciences, politics, religions, ethics. We have searched for low doors in the walls, or sometimes tried to vault over or burrow under. We feel a need to apologize for our limitations. We are well aware of the inadequacies of our knowledge and of our discernment. And yet such a search has no chance of succeeding unless those walls are breached. We hope that where we have failed, others will be inspired (or provoked) to do better.

What we are about to say draws on the findings of many sciences. We urge the reader to bear in mind the imperfection of our current knowledge. Science is never finished. It proceeds by successive approximations, edging closer and closer to a complete and accurate understanding of Nature, but it is never fully there. From the fact that so many major discoveries have been made in the last century—even in the last decade—it is clear that we still have far to go. Science is always subject to debate, correction, refinement, agonizing reappraisals, and revolutionary insights. Nevertheless, there now seems to be enough known to reconstruct some of the key steps that led to us and helped to make us who we are.

On our journey we encountered many who were generous with their time, expertise, wisdom, and encouragement, many who carefully and critically read all or part of the manuscript. As a result, deficiencies were removed, and errors of fact or interpretation corrected. We particularly thank Diane Ackerman; Christopher Chyba, Ames Research Center, NASA; Jonathan Cott; James F. Crow, Department of Genetics, University of Wisconsin, Madison; Richard Dawkins, Department of Zoology, Oxford University; Irven de Vore, Department of Anthropology, Harvard University; Frans B. M. de Waal, Department of Psychology, Emory University, and Yerkes Primate Research Center; James M. Dabbs, Jr., Department of Psychology, Georgia State University; Stephen Emlen, Section of Neurobiology and Behavior, Cornell University; Morris Goodman, Department of Anatomy and Cell Biology, Wayne State University School of Medicine; Stephen Jay Gould, Museum of Comparative Zoology, Harvard University; James L. Gould and Carol Grant Gould, Department of Biology, Princeton University; Lester Grinspoon, Department of Psychiatry, Harvard Medical School; Howard E. Gruber, Department of Developmental Psychology, Columbia University, Jon Lomberg; Nancy Palmer, Shorenstein Barone Center on the Press and Politics, Kennedy School of Government, Harvard University; Lynda Obst; William Provine, Departments of Genetics and of the History of Science, Cornell University; Duane M. Rumbaugh and E. Sue Savage-Rumbaugh, Language Research Center, Georgia State University; Dorion, Jeremy, and Nicholas Sagan; J. William Schopf, Center for the Study of Evolution and the Origin of Life, University of California, Los Angeles; Morty Sills; Steven Soter, Smithsonian Institution; Jeremy Stone, Federation of American Scientists; and Paul West. Many scientists kindly sent us pre-publication copies of their work. C.S. also thanks his early teachers in the life sciences, H. J. Muller, Sewall Wright, and Joshua Lederberg. Of course none of these people are responsible for any remaining errors.

We are deeply grateful to those who ushered this work through its various drafts. For excellence in library research, transcription, file keeping, and much else we owe a special debt of gratitude to A.D.’s assistant, Karenn Gobrecht, and to C.S.’s long-time Administrative Assistant at Cornell, Eleanor York. We also thank Nancy Birn Struckman, Dolores Higareda, Michelle Lane, Loren Mooney, Graham Parks, Deborah Pearlstein, and John P. Wolff. The superb facilities of the Cornell University library system were a critical resource in the writing of this book. We also could not have written it without the help of Maria Farge, Julia Ford Diamond, Lisbeth Collacchi, Mamie Jones, and Leona Cummings.

We are indebted to Scott Meredith and Jack Scovil of the Scott Meredith Literary Agency for unstinting encouragement and support. We are happy that Shadows has come to fruition during Ann Godoff’s tenure as our editor; and also thank Harry Evans, Joni Evans, Nancy Inglis, Jim Lambert, Carol Schneider, and Sam Vaughan at Random House.

Walter Anderson, the editor-in-chief of Parade magazine, has made it possible for us to present our ideas to the broadest possible audience. Working with him and Senior Editor David Currier has been an unalloyed pleasure.