Before it was thought that Neanderthals and the ancestors to modern humans interbred in an event around 65,000 years ago. However, a new study suggests that there was earlier contact between the two groups around 100,000 years ago due to the discovery of modern human DNA in Neanderthals. This discovery also suggest that these early modern humans left Africa before the migration event known as the “out of Africa” event around 47-65 thousand years ago.
People today of European, Eurasian and Asian ancestry have traces of Neanderthal DNA in their genome. This information implies that the children of Neanderthal-human parents lived amongst human populations outside of Africa where they then bred with other humans. On the other hand, present day Africans do not have these traces of Neanderthal DNA, which implies that the sexual contact between the two groups occurred outside of Africa.
These conclusions are drawn from comparing the complete genome of hundreds of present day humans and either the partial or complete genome of four archaic humans. One of these Neanderthals, dubbed the “Altai Neanderthal” due to its discovery in a cave in southwest Siberia, contained modern human genes. These gene sequences are linked to a group of modern human ancestors from Africa that separated from other humans sometime around 200,000 years ago.
This gene flow from a population closely related to modern humans into the Altai Neanderthal raise further questions about human migration out of Africa earlier than previously known. Why did these early humans move out of Africa and could there possibly be even earlier migration events than the one recently discovered? Did these groups co-exist in populations peacefully outside of Africa and if so, what led to the extinction of Neanderthals and other archaic human lineages? Great speculation exists around these ideas, but I’m glad we won because I would not want to look like a Neanderthal.
Cold Spring Harbor Laboratory. "Neanderthals mated with modern humans much earlier than previously thought, study finds: First genetic evidence of modern human DNA in a Neanderthal individual." ScienceDaily. ScienceDaily, 17 February 2016.
-Allen Currier (1)