Did Neanderthals Mate With Modern Humans?

When modern humans (Homo sapiens) migrated out of Africa around 140,000 to 100,000 years ago, it is likely that they ran into their more primitive cousins the Neanderthals (Homo neanderthalensis), who were already living in Europe. Both species probably evolved separately from the same ancestor, Homo erectus.

Did the two groups mate when they met? All we really know is that the Neanderthals disappeared about 28,000 years ago. Some scientists hypothesize that they were attacked or simply out-competed by modern humans; others claim that the two groups interbred, causing Neanderthal features to be absorbed into a larger population of modern humans.

Now there is new evidence that perhaps they did interbreed. Using modern DNA analysis techniques, scientists have determined that the Neanderthals have more genetic variations in common with present-day humans in Europe and Asia than with modern humans in Africa. These data suggest that interbreeding may have occurred if/when the two species met in Europe, before modern humans migrated out of Europe to Asia.