1. Laboratoire de Biologie évolutive, Ecologie et Gestion des Ecosystèmes, Département de Biologie animale, Université Cheikh Anta Diop de Dakar, Senegal
2. Department of World Languages and Cultures, Iowa State University, Ames, Iowa, U.S.A.
3. Instituto Jane Goodall de España, Barcelona, Spain
4. Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
5. Department of Anthropology, Iowa State University, Ames, IA 50011, U.S.A.