International Journal of Primatology

, Volume 19, Issue 6, pp 1013–1027 | Cite as

Seasonality and Socioecology: The Importance of Variation in Fruit Abundance to Bonobo Sociality

  • Frances J. White

Abstract

The assumption that nonseasonal, evergreen, rain forests contain more continuously available food resources than seasonal rain forests is fundamental to comparisons made between the socioecology of the male-bonded Pan troglodytes and the female-based social system of the Pan paniscus. Chimpanzee females may be less social due to the high costs of feeding competition, whereas in the more food-rich central African rain forests such as the Lomako forest, female bonobos can associate and socially bond. The Lomako Forest experiences two wet and two dry seasons a year. Data on fruit abundance and sociality show that despite monthly variation in fruit availability, there was no consistent seasonal variation in fruit abundance or dietary breadth. Bonobo use of nonfig fruits, figs, THV, and leaves did not follow seasonal patterns. Leaves and THV may act as complementary sources of plant protein and their use was inversely correlated. Monthly variation in fruit abundance was associated with a significant decrease in the number of males in a party but not in the number of females. Focal males were frequently solitary during 1 of the 3 months with the smallest party sizes. In contrast, females remained social with each other throughout the year. Therefore, seaonality at Lomako appeared to be less marked than at comparable chimpanzee sites, such that the variation in fruit abundance did not fall below a level that prohibits female sociality.

Pan paniscus bonobo seasonality feeding social bonds 

REFERENCES

  1. Badrian, A. J., and Badrian, N. L. (1984). Group composition and social structure of Pan paniscus in the Lomako Forest. In Susman, R. L. (ed.), The Pygmy Chimpanzee; Evolutionary Biology and Behavior, Plenum Press, New York, pp. 325–346.Google Scholar
  2. Badrian, N. L., and Malenky, R. K. (1984). Feeding ecology of Pan paniscus in the Lomako Forest, Zaïre. In Susman, R. L. (ed.), The Pygmy Chimpanzee; Evolutionary Biology and Behavior, Plenum Press, New York, pp. 275–299.Google Scholar
  3. Bygott, D. J. (1979). Agonistic behavior and dominance among wild chimpanzees. In Hamburg, D. A., and McCown, E. (eds.), The Great Apes, Benjamin Cummings, Palo Alto, CA, pp. 405–427.Google Scholar
  4. Chapman, C. A., White, F. J., and Wrangham, R. W. (1994). Party size in chimpanzees and bonobos: a reevaluation of theory based on two similarly forested sites. In Wrangham, R. W., McGrew, W. C., de Waal, F. B. M., and Heltne, P. G. (eds.), Chimpanzee Cultures, Harvard University Press, Cambridge, MA, pp. 41–57.Google Scholar
  5. Doran, D. (1997). Influence of seasonality on activity patterns, feeding behavior, ranging, and grouping patterns in Taï chimpanzees. Int. J. Primatol. 18: 183–206.Google Scholar
  6. Furuichi, T. (1987). Sexual swelling, receptivity, and grouping of wild pygmy chimpanzee females at Wamba, Zaire. Primates 28: 309–318.Google Scholar
  7. Goodall, J. (1968). The behaviour of free-living chimpanzees in the Gombe Stream Reserve. Anim. Behav. Monogr. 1: 161–331.Google Scholar
  8. Goodall, J. (1986). The chimpanzees of Gombe: Patterns of Behavior, Harvard University Press, Cambridge, MA.Google Scholar
  9. Goodall, J., Bandora, A., Bergman, E., Busse, C., Matama, H., Mpongo, E., Pierce, A., and Riss, D. (1979). Intercommunity interactions in the chimpanzee population of Gombe National Park. In Hamburg, D. A., and McCown, E. (eds.), The Great Apes, Benjamin Cummings, Palo Alto, CA, pp. 13–53.Google Scholar
  10. Haiperin, S. D. (1979). Temporary association patterns in free ranging chimpanzees: An assessment of individual grouping preferences. In Hamburg, D. A. and McCown, E. (eds.), The Great Apes, Benjamin Cummings, Palo Alto, CA, pp. 491–499.Google Scholar
  11. Kano, T. (1982). The social group of pygmy chimpanzees Pan paniscus of Wamba. Primates 23: 171–188.Google Scholar
  12. Kitamura, K. (1983). Pygmy chimpanzee association patterns in ranging. Primates 24: 1–12.Google Scholar
  13. Knott, C. D. (1998). Changes in orangutan caloric intake, energy balance, and ketones in response to fluctuating fruit availability. Int. J. Primatol. 19: 1061–1079.Google Scholar
  14. Kuroda, S. (1979). The social group of the pygmy chimpanzee. Primates 20: 161–183.Google Scholar
  15. Malenky, R. K. (1990). Ecological Factors Affecting Food Choice and Social Organization in Pan paniscus, Ph.D. thesis, State University of New York at Stony Brook.Google Scholar
  16. Malenky, R. K., and Wrangham, R. W. (1994). A quantitative comparison of terrestrial herbaceous food consumption by Pan paniscus in the Lomako Forest, Zaire, and Pan troglodytes in the Kibale Forest, Uganda. Am. J. Primatol. 32: 1–12.Google Scholar
  17. Malenky, R. K., Wrangham, R., Chapman, C. A., and Vineberg, E. O. (1993). Measuring chimpanzee food abundance. Tropics 2: 231–244.Google Scholar
  18. Nishida, T. (1979). The social structure of chimpanzees of the Mahale Mountains. In Hamburg, D. A., and McCown, E. R. (eds.), The Great Apes, Benjamin Cummings, Palo Alto, CA, pp. 72–121.Google Scholar
  19. Sokal, R. R. and Rohlf, F. J. (1995). Biometry, Freeman, New York.Google Scholar
  20. Terborgh, J. (1986). Community aspects of frugivory in tropical forests. In Junk, W. (ed.) Frugivores and Seed Dispersal, Kluwer, Dordrecht, The Netherlands, pp. 371–384.Google Scholar
  21. Tutin, C. E. G., McGrew, W. C., and Baldwin, P. J. (1983). Social organization of savanna-dwelling chimpanzees, Pan troglodytes verus, at Mt. Assirik, Senegal. Primates 24: 154–173.Google Scholar
  22. White, F. J. (1988). Party composition and dynamics in Pan paniscus. Int. J. Primatol. 9: 179–193.Google Scholar
  23. White, F. J. (1989). Ecological correlates of pygmy chimpanzee social structure. In Standen, V., and Foley, R. A. (eds.), Comparative Socioecology. The Behavioural Ecology of Humans and Other Mammals., Blackwell Scientific, Oxford, pp. 151–164.Google Scholar
  24. White, F. J. (1992a). Activity budgets, feeding behavior and habitat use of pygmy chimpanzees at Lomako, Zaire. Am. J. Primatol. 26: 215–223.Google Scholar
  25. White, F. J. (1992b). Pygmy chimpanzee social organization: variation with party size and between study sites. Am. J. Primatol. 26: 203–214.Google Scholar
  26. White, F. J. (1996a). Comparative socioecology of Pan paniscus. In McGrew, W. C., Nishida, T., and Marchant, L. (eds.), Great Ape Societies, Cambridge University Press, Cambridge, pp. 29–41.Google Scholar
  27. White, F. J. (1996b). Pan paniscus 1973 to 1996: Twenty-three years of field research. Evolutionary Anthropology 5: 161–167.Google Scholar
  28. White, F. J., and Burgman, M. A. (1990). Social organization of the pygmy chimpanzee (Pan paniscus): Multivariate analysis of intracommunity associations. Am. J. Phys. Anthropol. 83: 193–201.Google Scholar
  29. White, F. J., and Lanjouw, A. (1992). Feeding competition in Lomako bonobos: variation in social cohesion. In Nishida, T., McGrew, W. C., Marler, P., Pickford, M., and de Waal, F. B. M. (eds.) Topics in Primatology. Vol. 1. Human Origins, University of Tokyo Press, Tokyo, pp. 67–79.Google Scholar
  30. White, F. J., and Wrangham, R. W. (1988). Feeding competition and patch size in the chimpanzee species Pan paniscus and Pan troglodytes. Behaviour 105: 148–163.Google Scholar
  31. Wrangham, R. W. (1979a). On the evolution of ape social systems. Soc. Sci. Inform. 18: 335–368.Google Scholar
  32. Wrangham, R. W. (1979b). Sex differences in chimpanzee dispersion. In Hamburg, D. A., and McCown, E. R. (eds.), The Great Apes, Benjamin Cummings, Palo Alto, CA, pp. 481–489.Google Scholar
  33. Wrangham, R. W., Clark, A. P., and Isabirye-Basuta, G. (1992). Female social relationships and social organization of Kibale Forest chimpanzees. In Nishida, T., McGrew, W. C., Marler, P., Pickford, M., and de Waal, F. B. M. (eds.), Proceedings of the Symposia of XIII Congress of the International Primatological Society, Tokyo University Press, Tokyo, Japan, pp. 81–98.Google Scholar
  34. Wrangham, R. W., Chapman, C. A., Clark-Arcadi, A. P., and Isabirye-Basuta, G. (1996). Social ecology of Kanyawara chimpanzees: implications for understanding the costs of great ape groups. In McGrew, W. C., Nishida, T., and Marchant, L. (eds.), Great Ape Societies, Cambridge University Press, Cambridge, pp. 45–57. Table I. Dietary Breadth Calculated from the Number of Nonfig Tree Species Eaten in Each Month by Focal Animals and Averaged per Hour of Focal Sampling (Does Not Include Herbaceous Foods)Google Scholar

Copyright information

© Plenum Publishing Corporation 1998

Authors and Affiliations

  • Frances J. White
    • 1
  1. 1.Biological Anthropology and AnatomyDuke UniversityDurham

Personalised recommendations