Knife markings on a rediscovered bear bone suggest humans had settled in Ireland 2,500 years earlier than previously thought. Photo by IT Sligo

SLIGO, Ireland, March 21 (UPI) -- Researchers recently rediscovered an ancient bear bone recovered from a cave in Ireland in 1903. The 12,500-year-old bone features marks made by a stone tool, evidence that humans were present earlier than previously thought.

Until now, the earliest evidence of human presence in Ireland hailed from the Mesolithic period, no more than 10,000 years ago. In 1970s, archaeologists excavated an early human settlement at Mount Sandel Mesolithic site in Coleraine, County Londonderry. It was dated to 8,000 B.C.


Now, a bear bone has pushed back the arrival of early humans by some 2,500 years.

"Archaeologists have been searching for the Irish Palaeolithic since the 19th century, and now, finally, the first piece of the jigsaw has been revealed," Marion Dowd, an archaeologist at the Institute of Technology Sligo, said in a news release. "This find adds a new chapter to the human history of Ireland."

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Dowd is the lead author of a new paper on the discovery, published this week in the journal Quaternary Science Reviews.

The research was made possible by study co-author Ruth Carden, a research associate with the National Museum of Ireland, who found the bear bone in a cardboard box in a storage room of the museum. It had been sitting idly for nearly a century.

The bone was one of thousands recovered from Alice and Gwendoline Cave in the early part of the 20th century, but even the initial discoverers noted the distinct knife markings. However, the butchered bone was never dated.

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Carden and and Dowd changed that.

"When a Palaeolithic date was returned, it came as quite a shock," Dowd said. "Here we had evidence of someone butchering a brown bear carcass and cutting through the knee probably to extract the tendons. Yes, we expected a prehistoric date, but the Palaeolithic result took us completely by surprise."

The bear bone was freshly preserved in the cave, meaning it was brought to the cave shortly after being killed. The numerous markings suggest an early human was attempting to cut through the bear's knee joint, but was not very skilled or precise -- perhaps he or she was inexperienced.

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Dowd and Carden are now seeking funding to continue their analysis of other artifacts recovered during the 1903 cave excavations.