The two teeth were stumbled on throughout a paleontological expedition in Yukon's Historical Crow Basin in 1973.
Modern hyenas are known as hunters and scavengers in Asian and African ecosystems such as the savanna. In addition, the study has also helped to analyze the evolution of the feliform carnivoran mammals.
Their findings were printed on Tuesday in scientific journal Originate Quaternary.
About 10 years ago, Tseng heard from study co-author Lars Werdelin that a Yukon expedition had potentially uncovered some hyena fossils, but there wasn't any form of identification for them. Scientists used to believe that Chasmaporthetes were less capable of bone-cracking than other hyenas, but Tseng said they could crunch bones as well as they could cut through meat. Prior to this discovery, bones of the Chasmaporthetes have been found as far north as Mongolia and the southern United States, but nowhere in between the two regions. Fossils of this species had earlier been discovered in Europe, Africa, Asia and in the southern area of the US.
These fossils lend a hand connect the dots, and ascertain the hypothesis that they arrived to North The us from Russian Federation on the Bering Strait, Mr Zazula stated.
"It is awesome to imagine hyenas thriving in the harsh conditions above the Arctic Circle during the ice age", says study co-author Grant Zazula, Government of Yukon paleontologist. "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". While the most of the tracked fossil record locates this species in Europe, Asia and Africa, the new evidence of the fossilized teeth indicates that the hyena species roamed the Arctic plains.
The researchers said that their findings fill an important gap in scientists' knowledge of how hyenas reached North America.
Paleontologist Zhijie Jack Tseng from the University at Buffalo identified the teeth, which were kept at the Canadian Museum of Nature in Ottawa, as belonging to the Chasmaporthetes genus, also known as the "running hyenas" on account of their generally longer legs compared to other hyenas. One tooth was discovered by Richard "Dick" Harington, Gerry Fitzgerald and Charlie Thomas, and the other by Brenda Beebe and William Irving.
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. While the referred teeth were found to be a million years old; older teeth have been found in the continent of America, aged 4.7 million years. However, "based on the geologic and geographic record of the two different groups of hyenas, we concluded that these specimens are unlikely to be Adcrocuta", said Tseng. However, these fossils were found to be normal as the climates matched.