I have long thought that when comes to sex humans were much more like bonobos than our other close evolutionary relative, regular chimps. Paleo-anthropological evidence for ancestral behaviors is largely in the realm of the highly speculative, but a news story about Bradford University archaeologist Timothy Taylor's research on prehistoric sexual practices is interesting (if not dispositive). To wit:
He may have come down from the trees, but prehistoric man did not stop swinging. New research into Stone Age humans has argued that, far from having intercourse simply to reproduce, they had sex for fun.
Practices ranging from bondage to group sex, transvestism and the use of sex toys were widespread in primitive societies as a way of building up cultural ties.
Transvestism? In bear skins?
News story here.