The evolution of sexuality in chimpanzees and bonobos

Abstract

The evolution of nonconceptive sexuality in bonobos and chimpanzees is discussed from a functional perspective. Bonobos and chimpanzees have three functions of sexual activity in common (paternity confusion, practice sex, and exchange for favors), but only bonobos use sex purely for communication about social relationships. Bonobo hypersexuality appears closely linked to the evolution of female-female alliances. I suggest that these alliances were made possible by relaxed feeding competition, that they were favored through their effect on reducing sexual coercion, and that they are ultimately responsible for the relaxed social conditions that allowed the evolution of “communication sex.”

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Correspondence to Richard W. Wrangham.

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G. Benagiano and Roger Short kindly invited me to the October 1992 workshop on “The Evolution of the Meaning of Sexual Intercourse in the Human,” which stimulated this paper. Richard Connor, Irven DeVore, Marc Hauser, Sarah Hrdy, Barbara Smuts, and Frans de Waal made valuable comments; Jane Lancaster provided much help; and two anonymous reviewers gave remarkably quick and thorough advice. This article is to appear in modified form inThe Evolution of the Meaning of Human Sexual Intercourse (G. Benagiano, ed.).

Richard Wrangham is a Professor of Anthropology at Harvard University. He received his B.A. in Zoology at Oxford University, England (1970), and his Ph.D. in Zoology (Animal Behavior) from Cambridge University, England (1975). His research interests include socio-ecology, zoopharmacognosy, and the evolution of social relationships. He conducted field research with chimpanzees in Gombe from 1970 to 1973 and has directed a study of chimpanzees in Kibale Forest (Uganda) since 1987. He has also worked with moles, vervet monkeys, and people.

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Wrangham, R.W. The evolution of sexuality in chimpanzees and bonobos. Human Nature 4, 47–79 (1993). https://doi.org/10.1007/BF02734089

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Key words

  • Primate sexuality
  • Bonobos
  • Chimpanzees
  • Communication
  • Social relationships
  • Female Alliances