The period when Neanderthals and modern humans co-existed on Earth lasted longer than had previously been thought, new dating of European Neanderthal sites suggests.
International researchers conducting a detailed dating of bones and tools of Neanderthals say their evidence shows the two human species were living in the same areas for as long as 5,000 years before Neanderthals finally died out.
Bones and artifacts from important European archaeological sites from Russia in the east to Spain in the west show the two human groups coincided for a period of time sufficient for both interbreeding and interaction to take place, they say.
As a result, Neanderthals and their culture were absorbed into the population of the more modern humans and thus went extinct, although Neanderthal DNA exists in almost all human populations today, the researchers say.
The idea that Neanderthals were completely and quickly driven into extinction by modern humans and the competition they represented, as had long been believed, is a bit simplistic an explanation, researchers say.
"I think we can set aside the idea of a rapid extinction of Neanderthals caused solely by the arrival of modern humans," says lead researcher Thomas Higham from the University of Oxford. "Instead we can see a more complex process in which there is a much longer overlap between the two populations where there could have been exchanges of ideas and culture."
Some previous efforts to date Neanderthal existence in Europe has put the period of their overlap with modern humans at as little as 500 years, leading some to believe Neanderthals were slaughtered by modern humans or perhaps fell prey to new diseases for which they possessed no resistance.
However, new dating research suggests modern humans arrived in Europe earlier than previously thought, about 45,000 years ago, and Neanderthals existed until between 41,000 and 39,000 years ago, suggesting a coexistence of the two species that lasted at least 5,000 years.
Even so, genetic and archaeological research has shown Neanderthals were already declining in their numbers and suffering from inbreeding when modern humans first arrived.
And there can be little doubt that arrival added competitive pressures as the two groups encountered each other, says Chris Stringer of London's Natural History Museum.
"They were hunting the same animals, collecting the same plants and wanting to live in the best caves," he says.
That Neanderthals eventually succumbed to the pressure is clear, he says.
"But it was not an instantaneous extinction," he is quick to add. "They were not hunted down and killed by modern humans or wiped out by diseases they might have brought with them from Africa. It was a more gradual process."
