Roger Lewin is an Associate of the Peabody Museum at Harvard University. He is the author of half a dozen books on human origin research, three of which he co-authored with world-famous anthropologist Richard Leakey, as well as the author of the prize-winning Bones of Contention.

Robert Foley is the Director of the Leverhulme Centre for Human Evolutionary Studies at the University of Cambridge, and a fellow of King's College. He is the author of numerous articles and books on human evolution, including Another Unique Species (1987) and Humans before Humanity (1995). His research has focused on the links between human evolution and ecological and evolutionary mechanisms.