Modern-day hyenas live and hunt on the African Savannah but their ancient relatives once roamed the frozen world inside the Arctic Circle.
The predators likely roamed the tundra around a million years ago, hunting caribou and horses while also scavenging the remains of woolly mammoth carcasses.
Fossilised teeth found in the Yukon Territory in Canada date back to the last Ice Age and prove the animals slowly migrated to a warmer climate towards the equator.
Their habitat would have been a perennially semi-frozen steppe occupied by large amounts of wildlife, the study from the University of Buffalo adds.
The study reveals that two ice age fossil teeth, first discovered in the 1970s, belonged to the so-called ‘running hyena’ Chasmaporthetes.
This ice age fossil tooth — tucked away for years in the collections of the Canadian Museum of Nature – belonged to the ‘running hyena’ Chasmaporthetes, according to a new University at Buffalo-led study. This tooth, found in 1977, and one other are the first known hyena fossils found in the Arctic
Their findings, published in the journal Open Quaternary, describe the first known fossils of hyenas found in the Arctic.
Paleontologists have long-suspected the teeth belonged to hyenas, but previous studies were inconclusive.
Dr Jack Tseng, an assistant professor of pathology and anatomical sciences at the university, says this study is the first to confirm the origin of the teeth and report on them in detail.
The researchers said that their findings fill an important gap in scientists’ knowledge of how hyenas reached North America.
Previously, Chasmaporthetes fossils had been found as far north as Mongolia in Asia and the southern United States, with no sites in between.
Dr Tseng said: ‘Fossils of this genus of hyenas had been found in Africa, Europe and Asia, and also in the southern United States.
‘But where and how did these animals get to North America? The teeth we studied, even though they were just two teeth, start to answer those questions.’
He said ancient hyenas likely entered North America via Beringia, an area, including Alaska and Yukon Territory, that connected Asia with North America during periods of low sea levels.
From there, the research team believe that the animals made their way south and reached as far south as Mexico.
They said the newly described fossils are important in part because they provide the first proof of ancient hyenas living in Beringia.
‘It is amazing to imagine hyenas thriving in the harsh conditions above the Arctic Circle during the ice age.
This ice age fossil tooth – tucked away for years in the collections of the Canadian Museum of Nature – belonged to the ‘running hyena’ Chasmaporthetes, according to a new University at Buffalo-led study. This tooth, found in 1973, and one other are the first known hyena fossils found in the Arctic
An artist’s impression of ancient Arctic hyenas belonging to the genus Chasmaporthetes. A new study reports that two fossil teeth found in Yukon Territory in Canada belonged to Chasmaporthetes, making the teeth the first known fossils of hyenas found in the Arctic
Study co-author Dr Grant Zazula, a paleontologist with the Government of Yukon, said: ‘Chasmaporthetes probably hunted herds of ice age caribou and horses or scavenged carcasses of mammoths on the vast steppe-tundra that stretched from Siberia to Yukon Territory.’
Dr Tseng added: ‘Our previous understanding of where these far-ranging hyenas lived was based on fossil records in southern North America on one hand, and Asia, Europe and Africa on the other.
‘These rare records of hyenas in the Arctic fill in a massive gap in a location where we expected evidence of their crossing between continents, but had no proof until now.’
He says the fossil teeth are most likely between about 1.4 million and 850,000 years old, with ages more likely closer to the older figure.
But Dr Tseng added that the first hyenas crossed into North America long before that, as the earliest known hyena fossils on the continent date back about five million years.
The fossil teeth had been tucked away in the collections of the Canadian Museum of Nature and are among 50,000 fossils recovered from the area over the last century.