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Neanderthals re-imagined

Scientists are broadly rethinking the nature, skills and demise of the Neanderthals of Europe and Asia, steadily finding more ways that they were substantially like us and quite different from the limited, unchanging and ultimately doomed inferiors most commonly described in the past.

Artists Adrie and Alfons Kennis crafted this re-creation of a Neanderthal woman whose subspecies roamed Eurasia for almost 200,000 years. (Joe Mcnally) The latest revision involves Neanderthals who lived in southern Italy from about 42,000 to 35,000 years ago, a group that had to face fast-changing climate conditions that required them to adapt.

And that, says anthropologist Julien Riel-Salvatore, is precisely what they did: fashioning new hunting tools, targeting more-elusive prey and even wearing identifying ornaments and body painting.

Traditional Neanderthal theory has it that they changed their survival strategies only when they came into contact with more-modern early humans. But Riel-Salvatore, a professor at the University of Colorado at Denver writing in the Journal of Archaeological Method and Theory, says that was not the case in southern Italy.

"What we know is that the more-modern humans lived in northern Italy, more-traditional Neanderthals lived in middle Italy, and this group that adapted to a changing world was in the south - out of touch with the northern group," he said.

"Because of this Neanderthal buffer, it seems very unlikely that the southern Italy Neanderthals learned from the more-modern humans," he said. "They needed to change, and did, apparently by themselves."

He says this finding - along with recent investigations that have determined that between 1 and 4 percent of the human genome in Europe and Asia has Neanderthal genes - means that these often disparaged humans are actually "more like our brothers and sisters than even our cousins."

Handsome redheads?

Neanderthals roamed Eurasia from current-day Portugal to Siberia and from England to Jordan for almost 200,000 years. With brain sizes comparable to modern humans and bodies more barrel-chested but otherwise similar, they thrived during a time of relatively stable climate. They were not known to be advanced in toolmaking, but some argue that was because their surroundings didn't require it.

Named after the Neanderthal, the German valley where their remains were first excavated in 1856, they evolved from the African hominid Homo erectus. They were stockier than Homo sapiens and had thicker bones and protruding foreheads. Early study of Neanderthals described them as very hairy, brutish, unable to talk or walk like more-modern humans. Later discoveries overturned those views, and recent finds suggest quite a few in central Europe were handsome redheads.

More-modern humans began entering the same area from Africa 40,000 to 50,000 years ago and, within 10,000 years, the Neanderthals largely disappeared as a subspecies. This led many researchers to conclude that the Neanderthals were unable to change and compete with modern humans and as a result dwindled and died out.

More-recent thinking suggests that they faced a number of challenges between 40,000 and 30,000 years ago, not all of which came from the newcomers.

Stressful conditions

The long hot and cold cycles that had prevailed in Eurasia for centuries sped up during this time, making it more necessary and more difficult to adapt. In addition, a series of major volcanoes erupted in Italy and what is now Eastern Europe, further degrading the environment.

And finally, faced with the appearance of newcomers skilled in some ways they were not, the Neanderthals began to mate with them. Because Neanderthal numbers were low to begin with, Riel-Salvatore said, it was easy for them and their genomes to seemingly disappear into the population of more-modern humans.

"We have found no signs of conflict between the Neanderthals and the modern humans, but we do know the conditions that they lived in became more stressful," he said. "Neanderthals in southern Italy adapted well on their own for quite a long time, but ultimately succumbed."

At archaeological sites associated with the southern Italian Neanderthals, who are called Uluzzians, researchers have found pointed weapons, tools made from bones, ochre for coloring and possibly implements for fishing and small-game hunting - artifacts not previously associated with Neanderthals.

Research debunking the position that Neanderthals were "cognitively inferior" comes from Daniel Adler of the University of Connecticut and Metin Eren of Southern Methodist University.

In 2006, Adler described evidence that Neanderthals hunted just as well as Homo sapiens, even if their weapons were less sophisticated. In 2007, Eren replicated the making of Neanderthal disc-shaped tools, or "flakes," and found they were in some ways more efficient than Homo sapiens' blade-based tools. Both researchers said that while the Neanderthals did not make the transition to more advanced tools - which generations of researchers saw as proof of Homo sapiens' superiority - they were nonetheless well adapted to their environment.

"For many, the term 'Neanderthal' is still synonymous with 'knuckle-dragging thuggish brute,' " Adler said at the time. "We're going back and rehabilitating the image of the Neanderthals."

The research he conducted with an Israeli team focused on Neanderthal populations in the southern Caucasus. They found that the Neanderthals were able to hunt Caucasian tur, large mountain goats that took considerable skill to capture. They based their conclusion that Neanderthal and Homo sapiens weapons were roughly comparable in part on the fact that the tur killed by the Neanderthals were adults, the most difficult to track and bring down.

But while Adler argues strongly that late Neanderthals were more capable than traditionally believed, he is not convinced by Riel-Salvatore's scenario in Italy. He said the data described are limited, and he does not believe the southern group was uniformly Neanderthal.

"At the moment, the trend in our field is to think of the Neanderthals as being more like ourselves rather than the quintessential 'other,' " he said. "Julien's paper follows that trend, but it claims more than the data can actually deliver."

Dirty and smelly, but . . .

In 2007, Erik Trinkaus of Washington University in St. Louis published research into prehistoric fossil remains in Europe that showed a significant number of attributes associated with both the Neanderthals and more-modern humans.

"Both groups would seem to us dirty and smelly, but, cleaned up, we would understand both to be human," he said when the paper was released in the Proceedings of the National Academy of Sciences. "There's good reason to think that they did as well."

Subsequent research this year concluded that 1 to 4 percent of the modern human genome comes from Neanderthals, making the link tighter. And while the percentage may seem small, Riel-Salvatore says it has to be understood in context. Neanderthals, he said, probably never reached a total population greater than hundreds of thousands, while Homo sapiens came in far greater numbers.

"At one point I would imagine the amount of Neanderthal in modern humans was much greater," he said. "But with the numbers and generations, that percentage declined. Still, most Neanderthals were gone from the Earth by 28,000 years ago, but clearly some of them remain in many of us."

Author: Marc Kaufman | Source: The Washington Post [October 05, 2010]


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