Humans Did Not Wipe Out the Neanderthals, New Research Suggests
Neanderthals
went extinct in Europe about 40,000 years ago, giving them millennia to
coexist with modern humans culturally and sexually, new findings
suggest. This research also suggests that modern humans did not cause
Neanderthals to rapidly go extinct, as some researchers have previously…
Humans Did Not Wipe Out the Neanderthals, New Research Suggests
By Charles Q. Choi, Live Science Contributor
13 hours ago
A site in Abric Romani, Spain, where Neanderthal remains were found.
Neanderthals are the closest extinct relatives of modern humans, and lived in Europe and Asia. Recent findings suggest that Neanderthals were closely related enough to interbreed with ancestors of modern humans — about 1.5 to 2.1 percent of the DNA of anyone outside Africa is Neanderthal in origin.
It has long been uncertain when Neanderthals went extinct, and there
has been much debate over whether interactions with modern humans might
have driven their disappearance. Neanderthals entered Europe before
modern humans did, and prior studies had suggested the last of the
Neanderthals held out there on the Iberian Peninsula until about 35,000
years ago, potentially sharing the region with modern humans for
millennia. However, more recent findings suggested that some Neanderthal fossils from Europe might be thousands of years older
than previously thought, raising the possibility that Neanderthals went
extinct before modern humans arrived in Europe starting about 42,000
years ago. [The 10 Biggest Mysteries of the First Humans]
To help solve the mystery of when Neanderthals went extinct, scientists
analyzed bone, charcoal and shell materials from 40 archaeological
sites from Russia to Spain. They employed advanced techniques for more
precise dating of these specimens that involved ultra-filtering
molecules from bone samples for examination and removing organic
contaminants that could make specimens seem younger than they actually
are.
The new findings suggest that Neanderthals disappeared from Europe between about 41,000 and 39,000 years ago."I think that, for the first time, we have a reliable extinction date for Neanderthals," said study author Tom Higham, a radiocarbon scientist at the University of Oxford in England. "This has eluded us for decades."
The Neanderthal extinction occurred across sites ranging from the Black Sea to the Atlantic Coast of Europe. The timing and geography suggest Neanderthals may have overlapped with modern humans for 2,600 to 5,400 years, opening the door for genetic and cultural exchanges between the two groups for millennia.
These findings
suggest that modern humans did not rapidly replace Neanderthals in
Europe — say, via violent means. Rather, the Neanderthal extinction
"might have been more complex and drawn out than previously thought,"
Higham told Live Science.
There is some genetic evidence that
Neanderthals in Western Europe may have experienced declining genetic
diversity about the time when the first modern humans began arriving on
the continent, Higham said. "This might mean that they were fading out
at this time, although, of course, our evidence suggests that there was a
long period of overlap during which this occurred," he said.
Neanderthals may not even have truly disappeared, but instead have been
assimilated into modern human populations. "We know, of course, that we
have a genetic legacy from Neanderthals of about 1 to 2 percent, so
there was interbreeding," Higham said.
One mystery regarding sex between Neanderthals and modern humans is
that the greatest amount of interbreeding between the two lineages is
currently thought to have occurred about 77,000 to 114,000 years ago,
preceding any potential interbreeding in Europe. However, Higham noted
more recent as-yet-unpublished data suggest the interbreeding events
occurred about 55,000 to 60,000 years ago, more in tune with
interbreeding scenarios involving Europe. "What is needed is more
genetic analysis of human bone from this transitional period in Europe,"
Higham said.
In the future,
the researchers plan to extend their work into Eastern Europe and wider
Eurasia to widen their data set and look for more patterns in the data
pertaining to the Neanderthal extinction and the spread of modern
humans, Higham said.
The scientists detailed their findings in the Aug. 21 issue of the journal Nature.
- In Photos: Neanderthal Burials Uncovered
- In Photos: New Human Ancestor Possibly Unearthed in Spanish Cave
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