The tip of a girl’s 40000-year-old pinky finger found in a cold Siberian cave paired with faster and cheaper genetic sequencing technology is helping scientists draw a surprisingly complex new picture of human origins.
The new view is fast supplanting the traditional idea that modern humans triumphantly marched out of Africa about 50000 years ago replacing all other types that had gone before.
Instead the genetic analysis shows modern humans encountered and bred with at least two groups of ancient humans in relatively recent times: the Neanderthals who lived in Europe and Asia dying out roughly 30000 years ago and a mysterious group known as the Denisovans who lived in Asia and most likely vanished around the same time.
Their DNA lives on in us even though they are extinct. “In a sense we are a hybrid species” Chris Stringer a paleoanthropologist who is the research leader in human origins at the Natural History Museum in London said in an interview.
The Denisovans (pronounced dun-EE-suh-vinz) were first described a year ago in a groundbreaking paper in the journal Nature made possible by genetic sequencing of the girl’s pinky bone and of an oddly shaped molar from a young adult.
Although little is known about the Denisovans — the only remains so far are the pinky bone and the tooth and there are no artifacts like tools. Dr. Reich and others suggest that they were once scattered widely across Asia from the cold northern cave to the tropical south. The evidence is that modern populations in Oceania including aboriginal Australians carry Denisovan genes.
Read more: Subject: Mongrels
By ALANNA MITCHELL New York Times Op-Ed January 30 2012