Alan Walker is Professor of Anthropology at Pennsylvania State University. A Royal Society and MacArthur Fellow, he is a member of the National Academy of Sciences and the American Academy of Arts and Sciences. In 1996, he and Pat Shipman won the prestigious Rhône-Poulenc Prize for The Wisdom of the Bones. Pat Shipman is the author of many books, including The Invaders, The Animal Connection, and The Ape in the Tree (with Alan Walker), which won the W. W. Howells Award from the American Anthropological Association. Shipman is a fellow of the American Association for the Advancement of Science and the Royal Geographical Society of London.