Did Early Humans Start Walking for Sex?
Buried among the slew of papers about the new find is one about the creature’s sex life. It makes fascinating reading, especially if you like learning why human females don’t know when they are ovulating, and men lack the clacker-sized testicles and bristly penises sported by chimpanzees. (See pictures of Ardipithecus ramidus.) One of the defining attributes of Lucy and all other hominids—members of our evolutionary lineage, including ourselves—is that they walk upright on two legs. While Ardi also walked on two legs on the ground, the species also clambered about on four legs in the trees. Ardi thus offers a fascinating glimpse of an ape caught in the act of becoming human. (Interactive: Ardi’s key features.) The problem is it is doing it in the wrong place at the wrong time—at least according to conventional wisdom, which says our kind first stood up on two legs when they moved out of the forest and onto open savanna grasslands. At the time Ardi lived, her environment was a woodland,
