A toothy grinning monster lurked in a museum’s basement collection in Canada: the fossilized jawbone of a beast that once roamed the cliffs along the South Saskatchewan River, rivaling saber-toothed cats (Smilodon) in hunting horses, bison, camels and mammoths.

Researcher Ashley R. Reynolds of the Department of Natural History at the Royal Ontario Museum in Toronto decided to take a closer look at some past discoveries in light of new knowledge accumulated since the time of discovery. This practice has gained popularity in collections around the world during the pandemic lockdown and has led to many interesting discoveries, including the work Reynolds has published in the Journal of Quaternary Sciences.

Earlier efforts by Reynolds and his colleagues had revealed the first evidence of a Canadian saber-toothed cat (Smilodon fatalis) in the museum’s collection. In the current study, “The dreaded wolf (Canis dirus) from the late Pleistocene of southern Canada (Medicine Hat, Alberta)”, Reynolds analyzed more fossil material from the same dig site to positively identify a dreaded wolf from a fossilized jaw bone in the collection.

The fossil, originally found in 1969, was identified as a giant wolf by CS Churcher (an author of this paper) in an unpublished report to the Geological Survey of Canada in 1970, due to its large size. It was never illustrated or described in detail to confirm the original identification.

Dire wolves are a larger, extinct canid cousin of the gray wolf with more muscular builds and more powerful jaws. Three species of giant wolves ranged from North and South America east to China. They must have been a fierce competitor as their territory often overlapped with other large predators, most often saber-toothed cats three times their size.

It is unusual that the jawbone has not been studied for so long as the specimen is believed to be the first and only giant wolf found in Canada and the northernmost known occurrence of the species at 500 km. This could be because it was such an outlier that the initial observations lacked confidence for more formal identification.

Distinguishing between a gray wolf and a giant wolf from a poorly preserved fossil is difficult because the two are so close morphologically, despite estimates that the two are separated from having a common ancestor over 5.5 millions of years.

With a complete fossil jawbone in good condition, identification would have been straightforward, as the size and distinct patterns on the teeth can clearly separate the two. The fossil found in 1969 was in poor condition, fractured in several places and missing the most obvious clues on the surfaces of the teeth as some teeth were missing and the teeth that were preserved with the jawbone were either poorly preserved or naturally worn down by a wolf in advanced age.

Without the most obvious identifiers, the researchers took several measurements and compared them to known wolf fossils, modern gray wolves, and gray wolf ancestor fossils. In the analysis, there was some overlap with outliers between giant wolves and gray wolf ancestors, but the fossilized jawbone plots placed it firmly in the category of giant wolves, as originally suggested in the unpublished 1970 report. Radiocarbon-dated pieces of wood believed to be from where the jawbone was found date to around 45,000 years ago.

The study is a long-awaited survey, adding to the known range of territories inhabited by the dire wolf. The recent identification of a 40,000-year-old giant wolf fossil in northeast China, cited in the article, also hints at faunal migrations around the Canadian giant wolf period, suggesting that it crossed land bridge formations between Asia and North America. until the last ice age. As giant wolves may have lived as recently as 9,500 years ago, it’s possible they crossed paths with early humans migrating to Beringia.