Michael Tomasello is Co-Director of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Joan B. Silk has conducted extensive research on the social lives of monkeys and apes, including extended fieldwork on chimpanzees at Gombe Stream Reserve in Tanzania and on baboons in Kenya and Botswana. She is also interested in the application of evolutionary thinking to human behavior. She has published numerous articles in scientific journals and edited volumes. She is currently a professor in the School of Evolution and Social Change at Arizona State University.