Friday 9 January, 2009Oh, those cavemen! Kinky sex may be prehistoric

Human and chimpanzee ancestors may have been a LOT closer than we thought. Scientists at the Broad Institute of Harvard and MIT in the US report that some of the earliest members of the two species probably got it on together plenty before they finally split for good. The final breakup didn't come until 6.3-million years ago at most—probably less than 5.4-million years.

The new study builds on earlier genetic research, which had shown that chimps and humans developed from a common ancestor about 7 million years ago. By examining more recent data—approximately 800 times more DNA information than before—the researchers could trace the evolutionary history of the two species in far greater detail.

Turns out that a single ape species started to develop into something like humans and chimps about 10-million years ago. The sister species may have continued to breed with each other, creating hybrid offspring and making the whole process of separation a lot slower and more complicated than scientists had thought.

Apparently, some paleontologists think that knuckle-walking chimp ancestors and stand-up human types couldn't copulate, um, successfully. (Maybe they've been studying fossils a bit too long . . .) Other scientists, though, suggest that such new genetic research is putting some sizzle into the study of human origins.