GOTTFRIED HOHMANN is a Research Fellow in the Department of Primatology at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, researching bonobos. He has also co-edited Behavioural Differences in Chimpanzees and Bonobos with Christophe Boesch and Linda Marchant (2002, ISBN 0521803543).
MARTHA M. ROBBINS is a Research Associate in the Primatology Department of the Max Planck Institute for Evolutionary Anthropology. She studies the behavioural ecology and reproductive strategies of gorillas. She has also co-edited a volume Mountain Gorillas (2001 ISBN 0521780047) with Pascal Sicotte and Kelly Stewart.
CHRISTOPHE BOESCH is Director of the Department of Primatology at the Max Plank Institute for Evolutionary Anthropology. He has also co-edited books including Behavioural Differences in Chimpanzees and Bonobos, with Gottfried Hohmann and Linda Marchant (2002, ISBN 0521803543), as well as Monogamy with Ulrich Reichard (2003, ISBN 0521819733).