Cavemen & modern humans… they got it on.

DNA analysis presented at the Royal Society in London shows, Nature says in the most delicate way possible, that ancient humans were getting it on more than we suspected:

The ancient genomes, one from a Neanderthal and one from a member of an archaic human group called the Denisovans, were presented on 18 November at a meeting on ancient DNA at the Royal Society in London. The results suggest that interbreeding went on between the members of several ancient human-like groups in Europe and Asia more than 30,000 years ago, including an as-yet-unknown human ancestor from Asia.

“What it begins to suggest is that we’re looking at a Lord of the Rings-type world — that there were many hominid populations,” says Mark Thomas, an evolutionary geneticist at University College London who was at the meeting but was not involved in the work.

The Denisovan genome indicates that the population got around: [David] Reich[, an evolutionary geneticist at Harvard Medical School,] said at the meeting that as well as interbreeding with the ancestors of Oceanians, they also bred with Neanderthals and the ancestors of modern humans in China and other parts of East Asia. Most surprisingly, Reich said, the genomes indicate that Denisovans interbred with yet another extinct population of archaic humans that lived in Asia more than 30,000 years ago — one that is neither human nor Neanderthal.