Neanderthals And Humans Didn’t Mate As Early As Thought: DNA From 45,000-Year-Old Bone Provides New Evidence
Our Neanderthal and human ancestors might not have gotten along as well as scientists thought they did. DNA analysis on a 45,000-year-old man’s bone found by an ivory carver in Siberia has provided evidence that the two groups did not begin mating until thousands of years after it is commonly believed they did.
The thigh bone from a Ust’-Ishim man is the oldest human bone found outside of Africa and the Middle East — nearly twice as old as a boy’s bone found earlier, also in Siberia.
Modern humans are the only surviving human lineage, but thousands of years ago others shared the earth with them. Humans’ closest relatives, now extinct, were the Neanderthals, who occupied Europe and Asia until about 30,000 years ago. However, The Inquistr reported earlier in October that recent findings may show Neanderthals actually died out 10,000 years earlier than that.
According to Live Science, archaeological finds suggest both Neanderthals and modern humans occupied the same areas as long as 100,000 years ago and had probably been mating during that time. The study also theorized that breeding between the two groups ended between 47,000 and 65,000 years ago, based on recent findings showing that 1.5 to 2.1 percent of the DNA in all people living outside of Africa is Neanderthal in origin.
However, the new DNA evidence points to a much later date that the two groups began interbreeding — and therefore, for a shorter period of time.
National Geographic reports that by analyzing the man’s complete genetic map with DNA obtained from the man’s bone, scientists were able to determine that his Neanderthal and human ancestors had first mated approximately 7,000 to 13,000 years before he lived — or between 50,000 and 60,000 years ago.
The scientists also discovered that the man’s DNA had a similar level of Neanderthal ancestry as present-day Eurasians and Native Americans.
“It’s really exciting that we now have a really high-quality genome sequence of an early modern human that is this old,” said one of the study’s authors, Janet Kelso.
The DNA evidence in the thigh bone has also changed scientists’ views on how modern humans colonized Eurasia. It was previously believed that early humans migrating from Africa and the Middle East first took a more southern route, and then later moved into mainland Asia. However, the fact that they have found evidence of a modern human in Siberia that dates back that far indicates that their migration routes may be have been different than originally thought.
University of Wisconsin paleoanthropologist John Hawks said of the new finding, “I think the paper is pretty convincing on this.”
He pointed out, though, that the 20,000 or so years it indicates Neanderthals and humans interbred “almost certainly is an oversimplification. The contacts could have extended over a longer period.”
[Image via Voice of America]