A giant skull discovered on a beach in northernmost Alaska may belong to a subspecies of polar bear that’s never before been reported by scientists. But the elusive bear may have long been familiar to indigenous people in the Arctic.

The single, hefty bone is the fourth largest polar bear skull ever found, measuring 410 millimeters, or just over 16 inches, from the tip of the nose to the back of the skull, and it has what experts describe as an unusually slender and elongated shape.

Radiocarbon dating has shown the skull to be about 1,300 years old.

But the giant bear may have descendants living today that have inspired native accounts of enormous, 12-foot long bears, sometimes referred to as “king bears” or “weasel bears,” said Dr. Anne Jensen, who reported the find.

“We don’t know the exact size [of the whole animal], but we do know it was a huge bear,” Jensen said in an interview.

The skull was found eroding out of a bank after a storm in 2014, at an archaeological site known as Walapka, just a few miles from Utqiaġvik, formerly known as Barrow, Alaska.

The cranium likely belonged to a male that lived a relatively long life, Jensen noted.

“It is adult, and not a young one, since all the cranial sutures — places where the skull plates join — are fused and can barely be seen,” she said.

Given the date of the specimen, with a radiocarbon sample ranging from the years 670 to 800 CE, the researchers dubbed the specimen “The Old One.”

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But beyond its mere age and size, there was something unique about this bear, Jensen said.

“The main thing is the differences in the skull morphology, the shape of the skull,” she said.

The back of the skull is longer and comparatively narrow, for example, she said, with features that are noticeably different from those of modern polar bears.

“The front part of the skull, from roughly the eyes forward, is like that of typical polar bears,” Jensen said.

“The back part of the skull is noticeably longer than other bear skulls to which we were able to compare it.

“One of those skulls was from quite a large bear, and the front part of the two skulls were not that different in length, but the back parts were strikingly different.”

One of Jensen’s colleagues, research biologist and wildlife veterinarian Dr. Raphaela Stimmelmayr, compared the skull of The Old One to more than 300 other polar bear skulls in the collection of University of Alaska Museum of the North.

She found several others with a similar shape and features, so it seems likely that The Old One is not entirely unique.

“It’s possible it’s a subspecies,” Jensen said, “or perhaps it’s more like [with] domestic dogs, where a borzoi and pug are considered members of the same species, [and] not [a] subspecies, even though their skulls are far more different than this is from a standard polar bear skull.”

When asked if other polar bears the size of the Old One may still be wandering the Arctic, Jensen said, “Certainly.”

This may not come as news to many of the indigenous peoples in the region, she added.

Ethnographers have recorded accounts of outsized polar bears from many Inuit groups, Jensen said.

The Inuvialuit of Canada’s Northwest Territories, for example, have tales of a giant “weasel bear,” while the native peoples of St. Lawrence Island and elsewhere relate accounts of a so-called “king bear.”

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Ethnographic accounts from around Utqiaġvik, however, don’t seem to include any such giant bear, Jensen noted.

“That may be because these bears were not around during the period when people were collecting ethnographic accounts — somewhat later here than in Canada — or because people just didn’t ask the right questions,” she said.

Jensen and her colleagues hope to research the skull further, including DNA analysis and a cross-sectioning of some of its teeth.

But for now, her attention is focused on the nearby ancient settlement of Walapka, a site inhabited periodically over the course of 4,000 years, whose residents may once have lived alongside bears like The Old One.

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“All this information can help us understand how past cultures functioned in a very difficult environment,” she said.

Jensen reported her team’s findings at the Alaska Marine Science Symposium in Anchorage, Alaska.