Linda F. Marchant is Professor of Biological Anthropology in the Department of Anthropology at Miami University, Ohio, USA

Preface G. Hohmann, C. Boesche and L. F. Marchant; Main introduction C. Boesche; Part I. Behavioural Flexibility: Introduction T. Matsuzawa; 1. Multivariate and phylogenetic approaches to understanding chimpanzee and bonobo behavioural diversity D. M. Doran, W. L. Jungers, Y. Sugiyama, J. G. Fleagle and C. P. Heesy; 2. Chimpanzees in the dry habitats of Mont Assirik, Senegal and Semliki Wildlife Reserve, Uganda K. D. Hunt and W. C. McGrew; 3. Behavioural adaptations to water scarcity in Tongo chimpanzees A. Lanjouw; 4. Bonobos of the Lukuru Wildlife Research Project J. Myers-Thompson; 5. Grooming-hand-clasp in Mahale M Group chimpanzees: implications for culture in social behaviours M. Nakamura; Part II. Social Relations: Introduction V. Reynolds; 6. Factors influencing fission-fusion grouping in chimpanzees in the Tai National Park, Cote d'Ivoire D. P. Anderson, E. V. Nordheim and C. Boesch; 7. Ecological and social correlates of chimpanzee party size and composition J. C. Mitani, D. P. Watts and J. S. Lwanga; 8. Agonistic relations among Kanyawara chimpanzees M. N. Muller; 9. Relationships of male chimpanzees in the Budongo Forest, Uganda N. E. Newton-Fisher; 10. Dynamics in social organisation of bonobos (Pan paniscus) G. Hohmann and B. Fruth; Part III. Female Strategies: The Females That Did Evolve: Introduction M. F. Small; 11. Why female bonobos have a lower copulation rate during estrus than chimpanzees T. Furuichi and C. Hashimoto; 12. Social relationships between cycling females and adult males in Mahale chimpanzees A. Matsumoto-Oda; 13. Seasonal aspects of reproduction and sexual behaviour in two chimpanzee populations: a comparison of Gombe (Tanzania) and Budongo (Uganda) J. Wallis; 14. Costs and benefits of grouping for female chimpanzees at Gombe J. M. Williams, H.-Y. Liu and A. E. Pusey; 15. The cost of sexual attraction: is there a trade-off in female Pan between sex appeal and received coercion? R. Wrangham; Part IV. Hunting and Food Sharing: Introduction L. F. Marchant; 16. Variations in chimpanzee-red colobus interactions C. Boesch, S. Uehara and H. Ihobe; 17. How bonobos handle hunts and harvests: why share food? B. Fruth and G. Hohmann; 18. Hunting and meat sharing by chimpanzees at Ngogo, Kibale National Park, Uganda D. P. Watts and J. C. Mitani; Part V. Genetic Diversity: 19. The evolutionary genetics and molecular ecology of chimpanzees and bonobos B. J. Bradley and L. Vigilant; References; Index.