Ah, bonobos, the crown jewel of God's creation! Let's not get me started on bonobos. Let's instead read this delightful article by Mr. Frans de Waal, a famed zoologist and bonobo enthusiast par excellence!
I have to quote myself now:
"Bonobos are the close cousins of both humans and chimpanzees, who surprisingly show very different behaviour patterns from both us and the chimps. In short, bonobos seem to have taken to heart the hippy byword 'Make love, not war'. Male bonobos tolerate both females and infants well, and although the discussion is still raging on, it seems that indeed females lead the bonobo societies through forming close, mutually co-operative alliances between non-related, adult females. Males inherit heir mother's rank and stay with their mother's group, whereas females migrate from their birth group upon maturity (this is a feature shared with the chimps, however, with totally different social consequences). In any case, bonobos are not as hierarchical animals as chimps, and use sex and grooming to relieve tension between members of the group instead of violence and dominance.
See
http://songweaver.com/info/bonobos.html for
Bonobo Sex and Society
The behavior of a close relative challenges assumptions about male supremacy in human evolution
by
Frans B. M. de Waal
(Originally published in the March 1995 issue of SCIENTIFIC AMERICAN, pp. 82-88)
A more scientific article, where de Waal shows that bonobos engage in sex for other than reproductive purposes, appear to use sex as way to relieve intra-group tension, and speculates that non-reproductive use of sex might have evolved to enable more peaceful and co-operative male-female relationships (in less-scientific terms, female bonobos distract males with sex and help themselves during intercourse to the food the male has gathered) can be found in
de Waal, Frans B. M. (1995): Sex as an Alternative to Aggression in the Bonobo. In Sexual Nature, Sexual Culture (Paul R. Abramson & Steven D. Pinkerton, eds.), pp. 37-56. Chicago/London: University of Chicago Press."
End bonobo ramble. Hope the link works.