A new study, published
in the journal Nature, suggests that humans and Neanderthals could have lived
side by side in Europe for up to 5,000 years, much longer than previously
believed.
William Davies, who wrote on editorial accompanying the paper,
says the new research supports the theory that the two species met, interbred
and even exchanged toolmaking techniques and artistic ideas across parts of
Europe.
Neanderthals
are modern humanity’s (Homo sapiens) closest cousins,
sharing about 99.5 percent of our DNA. Scientists believe they originated in
Africa and migrated to Europe at least 200,000 years ago, possibly tens of
thousands of years earlier. Because Homo sapiens did not begin its northern
migration until about 60,000 years ago, the two species evolved under very
different conditions.
Previous
research had suggested that modern humans arrived in Neanderthal-dominated
Europe about 40,000 years ago. Based on more reliable dating techniques,
researchers now push that estimate back to about 45,000 years.
5000
years is quite a long time in human terms, about 250 generations, explains
Davies, an associate professor in the Department of Archaeology at the
University of Southampton in the UK. Given this amount of time on the same
continent, the two species may have had considerable influence on one another.
The
new chronology gives scientists a new basis for “assessing just how much potential
there was for overlap,” Davies says. “Therefore we can start looking more
closely at the artifacts they left behind and seeing whether we can identify
the exchange of ideas.”
During
this period of human evolution Neanderthals and Homo sapiens shared many
similarities — anatomically, physically and intellectually. “I like to tell my
students that perhaps looking at Neanderthals [is] the closest we'll get to
looking at an alien human intelligence. It's something that's like us, but not
necessarily exactly like us. They're not just watered down versions of us —
they're their own beings.”
The
enduring mystery of the Neanderthals is why and how they died out within such a
brief time span while homo sapiens survived. In theory, the Neanderthals,
having adapted to conditions in Europe and possessed of equal intelligence and
more physcial strength, should have been better equipped than Homo sapiens to
survive.
“They
ruled Europe and Asia for quite a long time before we showed up,” Davies says.
“[T]hey reached from Spain and Portugal, into what is now Israel, and all
across southern Siberia. They were very, very successful and we shouldn't
underestimate that success.”
Davies
says there are many possible reasons to explain why Neanderthals went extinct.
A major climatic event, for example, or some other kind of natural disaster
might have isolated small pockets of them, causing the population to rapidly
shrink. Other researchers believe they vanished because our species, Homo
sapiens, arrived and out-competed them.
“I
think, like all explanations, it's probably a mixture of different factors,
some environmental, some other human groups that had this effect on them — and
probably it varied from region to region,” Davies says.
