Phillip V. Tobias is Professor Emeritus at the University of the Witwatersrand, Johannesburg, where he obtained his medical doctorate, PhD and DSc and where he served as Chair of the Department of Anatomy for 32 years. He has carried out researches on mammalian chromosomes, human biology of the peoples of Southern Africa, secular trends, somatotypes, hominin evolution, the history of anatomy and anthropology. He is Director of the Sterkfontein Research Unit and has conducted researches at this famous hominid site since 1966. His published works exceed 1000 items including 40 books and monographs and over 90 chapters in books.

Michael Raath is a vertebrate palaeontologist whose research interests focus on archosaurian and therapsid reptiles, rather than on hominids. But, as with most people, he is also inquisitive about human origins. He is a former director of the Bernard Price Institute for Palaeontological Research at the University of the Witwatersrand, Johannesburg.

Jacopo Moggi-Cecchi is Researcher at the Istituto di Antropologia, University of Florence. He obtained his Doctorate in 1989 and since then he has been intermittently working at the University of the Witwatersrand, Johannesburg to study the collections of South African fossil hominids. His main research interest is the study of the dentition, with special reference to aspects of dental development of juvenile specimens.

Gerald A. Doyle joined the staff of the University of the Witwatersrand, Johannesburg shortly after completing hid PhD at Western Reserve University, Cleveland, Ohio, and is now Professor Emeritus of Comparative Psychology and Honorary Professorial Research Fellow at the same university. A former Director of the Primate Behaviour Research Group, Professor Doyle is author/editor of a number of books on prosimian biology and is the founding editor of the International Journal of Primatology. Currently he is engaged on a book on the behaviour of the early hominids.