Scientists recovered the DNA code of a human relative recently discovered in Siberia, and it delivered a surprise: This relative roamed far from the cave that holds its only known remains.
By comparing the DNA to that of modern populations, scientists found evidence that these "Denisovans" from more than 30,000 years ago ranged all across Asia. They apparently interbred with the ancestors of people now living in Melanesia, a group of islands northeast of Australia.
There's no sign that Denisovans mingled with the ancestors of people now living in Eurasia, which made the connection between Siberia and distant Melanesia quite a shock.
It's the second report in recent months of using a new tool, genomes of ancient human relatives, to illuminate the evolutionary history of humankind. In May, some of the same scientists reported using the Neanderthal genome to show that Neanderthals interbred with ancestors of today's non-African populations. That might have happened in the Middle East after the ancestors left Africa but before they entered Eurasia, researchers said.
The existence of a new human relative was first revealed just nine months ago from a sampling of DNA recovered from a finger bone discovered in the Denisova Cave in southern Siberia. Researchers proposed the informal name Denisovans for them in today's issue of the journal Nature, where they report the new results.
There's not enough evidence to determine whether Denisovans are a distinct species, the researchers said.
The genome, recovered from the finger bone, showed Denisovans are more closely related to Neanderthals than to modern humans. That indicates that both they and Neanderthals sprang from a common ancestor on a different branch of the evolutionary family tree than the one leading to modern humans.