Photographs of two stone artifacts from Byzovaya. 1, Keilmesser; 2, Levallois core, preferential method. Photo: By Hugues Plisson/ AAAS

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Scientists have identified what may be one of the last northern refuges of Neanderthals, a spot near the Arctic Circle in Russia with artifacts dated to 31,000 to 34,000 years ago.

Stone tools and flakes found there look like the work of Neanderthals, the stocky, muscular hunters who lived in Europe and western Asia until they were replaced by modern humans, researchers reported Thursday in the journal Science.

The site lies along the Pechora River west of the Ural Mountains, about 92 miles south of the Arctic Circle. Researchers dated it from animal bones and sand grains. Nobody has found any human bones or DNA that could provide stronger evidence that Neanderthals lived there, report the scientists, from Russia, France and Norway. The artifacts had been collected during various expeditions.

Neanderthals first appeared more than 200,000 years ago. They died out sometime after modern humans arrived in Europe, which occurred some 40,000 to 45,000 years ago.

Richard Klein, a Stanford University professor of anthropology, said the artifacts do look like the work of Neanderthals, but that it's also possible they were made by modern people instead.

Neanderthals were not previously known to be in that area, nor convincingly shown to be present anywhere at such a recent time, he said. Finding another site or human bones would help settle the question, he said.

Eric Delson, a paleoanthropologist at Lehman College of the City of New York, cited a 2006 study that suggests Neanderthals occupied a cave near the southern tip of Spain at about the same time as the new work puts them in Russia. Maybe the two locations show how Neanderthals retreated in opposite directions from the encroachment of the modern humans, he said.

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