A single bear bone has transformed what we thought we knew about Irish history, showing humans were tromping through the country 2,500 years earlier than history books claim.

The bone with seven cuts from a sharp tool was found among thousands of bones in a cave on the island's west coast in 1903. While it sparked the interest of archaeologists at the time, radiocarbon dating was still decades off.

When Marion Dowd and Ruth Carden rediscovered it in a cardboard box at the National Museum of Ireland between 2010 and 2011, they believed it could be significant and sent it for testing.

But "when a Palaeolithic date was returned, it came as quite a shock," Dowd tells the Independent. Experts say the man-made cuts were made when the bear was killed about 12,500 years ago, meaning the bone provides the earliest evidence of humans in Ireland.

Apart from the bear bone, the earliest evidence of human life in Ireland is about 10,000 years old and was found in the 1970s, per a release.

"Archaeologists have been searching for the Irish Palaeolithic since the 19th century, and now, finally, the first piece of the jigsaw has been revealed," says Dowd, who notes an inexperienced butcher probably used a long flint blade to cut through the knee and pull out the bear's tendons.

"This find adds a new chapter to the human history of Ireland." But that's not all. The bone also opens up the possibility of human interference in the case of animal extinctions in Ireland in the Palaeolithic period.

"From a zoological point of view, this is very exciting," says Carden. "It's time to start thinking outside the box." (This mummified puppy dates to the same period.)

This article originally appeared on Newser: Bear Bone Found in 1903 Alters the Story of Ireland

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