Wednesday, December 3, 2014

Mystery Humans

Updated genome sequences from two extinct relatives of modern humans suggest that these ‘archaic’ groups bred with humans and with each other more extensively than was previously known.

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 first published Neanderthal and Denisovan genome sequences revolutionized the study of ancient human history, not least because they showed that these groups bred with anatomically modern humans, contributing to the genetic diversity of many people alive today. (...)

The Denisovan genome indicates that the population got around: Reich 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.

by Ewen Callaway, Nature |  Read more:
Image: Ria Novosti/SPL