bonobo

Bonobos are the closest non-human relatives to us, with slightly more identical DNA than the chimpanzees who are second-closest. It is believed that all three descend from a common ancestor and that perhaps humans have inherited the capability for both the chimp's warlike nature and the bonobo's more peaceful tendencies.

It's worth noting that bonobos are matriarchal. The males are physically bigger than the females, but the females have learned to band together to enforce order.

And speaking of hangups, the first studies of the Bonobos couched some of their findings in Latin for fear of causing offense:

Sex, it turned out, is the key to the social life of the bonobo. The first suggestion that the sexual behavior of bonobos is different had come from observations at European zoos. Wrapping their findings in Latin, primatologists Eduard Tratz and Heinz Heck reported in 1954 that the chimpanzees at Hellabrun mated more canum (like dogs) and bonobos more hominum (like people). In those days, face-to- face copulation was considered uniquely human, a cultural innovation that needed to be taught to preliterate people (hence the term "missionary position"). These early studies, written in German, were ignored by the international scientific establishment. The bonobo's humanlike sexuality needed to be rediscovered in the 1970s before it became accepted as characteristic of the species.

Bonobo Sex and Society

One of the hornier species of primates, besides us humans (and with far fewer hangups about same-gender sexual relations). Remarkably peaceful apes.