This past February, Jack Tseng sat down in a warehouse room at the Canadian Museum of Nature’s research facilities in Gatineau, Quebec, to examine a pair of million-year-old teeth. Peering through a microscope, he studied their cusps and ridges. “Within 5 minutes, I could tell,” he said. These were the teeth of ancient hyenas — specifically Chasmaporthetes, or “running hyenas,” known for their speed and endurance.
Although only four hyena species exist today, the prehistoric world was full of them: nearly 70 species are currently known to have once roamed the planet. Signs of running hyenas specifically have been found across the southern United States and Mexico, as well as in Africa, Asia and Europe.
But these teeth, officially identified Tuesday in the journal Open Quaternary, provide the first evidence that hyenas also lived north of the Arctic Circle. They help map the species’ route of dispersal, suggesting the hyenas crossed the Bering land bridge from Asia into North America, just as humans most likely did.
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In order to make it into the scientific record, the teeth — which the researchers think are between 850,000 and 1.4 million years old — endured a bit of an odyssey themselves. After spending millenniums buried in Yukon sediment, they weathered additional decades of obscurity in the museum’s deep storage — a common type of fossil purgatory, currently occupied by countless specimens worldwide.
“Fossils get refossilized in museums,” said Dr. Tseng, an evolutionary biologist at the University at Buffalo.
He is an advocate for these forgotten fossils, and makes a point of revisiting existing collections to see what treasures might hide in them. In 2017, Dr. Tseng helped to describe two new species of prehistoric beardog based on previously discovered skulls.
The hyena find came from a decades-long game of scientific telephone. In the 1970s, two sets of researchers each found a tooth in the Yukon Territory’s Old Crow Basin, an area so paleontologically generous that some have described it as a “supermarket for fossils,” Dr. Tseng said. In the past, the basin has coughed up evidence of giant camels, proto-wild dogs and Pleistocene peccaries, expanding each species’ previously known range.
Suspecting the tooth she found had belonged to a hyena, Brenda Beebe, a paleontologist at the University of Toronto, sent photos and details to another expert, Björn Kurtén of Finland, who filed the correspondence away. After Dr. Kurtén died in 1988, his former student, Lars Werdelin, found Dr. Beebe’s letter.
He, too, forgot about it until a couple of years ago, when it resurfaced “during an office move,” said Dr. Werdelin, one of the paper’s co-authors. He then told Dr. Tseng, who headed to Ottawa to see the teeth for himself.
Dr. Tseng’s identification is convincing, and the study “fills an important gap in our understanding” of ancient hyena dispersal, said Duane Froese, an environmental scientist at the University of Alberta who was not involved in the research.
“It’s tremendously cool to think of hyenas in the Arctic,” he said.
Mysteries remain. After all, “it’s just two teeth,” said Dr. Tseng. But they serve as points on which to hang informed speculation. In the team’s renderings, they imagine the hyenas with white fur, for camouflage in the Arctic ice. And because Chasmaporthetes were likely strong enough to crack bones, they may have played an important nutrient-recycling role in the prehistoric ecosystem, breaking down the carcasses of large animals like mammoths, caribou and horses.
A question of national pride, though, is finally settled. “Americans had the hyenas,” said Dr. Tseng, and now Canada has them too. It just took a little while to find out.
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