Nerds of all stripes — be they casual Game of Thrones watchers or dedicated Dungeons & Dragons enthusiasts — will likely recognize the dire wolf (Canis dirus) as a fearsome, more powerfully built version of the wolves that inhabit the real world today.
But the creatures aren’t limited to the pages of George R.R. Martin’s perpetually unfinished fantasy series. They were once very real ice-age predators. And thanks to a team of scientists using computers to examine decades-old specimens, experts are revising their opinions of just how far north the animals used to live.
A dire wolf skeleton on display at the Royal Ontario Museum. This specimen was originally found in the La Brea Tarpits. Photo: Royal Ontario Museum
Between 1965 and 1970, two Canadian scientists named C.S. Churcher and Archibald MacS. Stalker (yes, really) collected over 1,200 vertebrate fossils from a deposit in the Medicine Hat area of southeastern Alberta.
Among that trove was a badly worn and crushed jawbone that Churcher suspected might belong to a dire wolf. But he never fully described the specimen, and it languished in a collection for over 50 years. Until now.
The area where two scientists in the late 1960s discovered the jawbone fossil, along with over 1,000 more vertebrate fossils. Map/Photo: Ashley Reynolds/Royal Ontario Museum/Journal of Quaternary Science
Using computer-aided technology, evolutionary biologist Ashley Reynolds and her team took a fresh look at the specimen and determined that it belonged to a dire wolf. The team published its findings earlier this month.
The confirmation is significant because, until recently, dire wolves were thought to live south of modern-day Canada. Between the Medicine Hat specimen and an example found in northern China and described in 2020, that understanding is changing.
The tooth hurts
Although dire wolves were larger than grey wolves, the Medicine Hat specimen fell into a range that could belong to either species. Further complicating matters were three factors: the age of the specimen (between 25,000 and 50,000 years old), the condition of the specimen (crushed and mangled), and the age of the animal it belonged to (advanced).
This last is particularly noteworthy, as one way that scientists differentiate between dire wolf and grey wolf fossils is the size and shape of their teeth. But the jawbone fossil apparently belonged to a grizzled old veteran.
Top: the lower jaw of a grey wolf. Middle: a dire wolf specimen collected from Peru. Lower: The Medicine Hat jawbone. Photo: Ashley Reynolds/Royal Ontario Museum/Journal of Quaternary Science
Researchers had struggled with the dilapidated remnant. Life is especially hard on predators’ teeth, and the older an animal is, the more wrecked the dentition. “Features of the teeth get worn away,” Reynolds told the CBC, so gleaning detailed information can be frustrating.
Computers to the rescue. Using technology that was unavailable in the 1970s, Reynolds and the team created an accurate digital version of what the jawbone looked like before years of chewing did their work. Then they compared that representation to better-preserved dire wolf specimens like those found in the La Brea Tar Pits.
Finally, after 50 years, the specimen was definitively labeled. The jawbone belonged to a dire wolf.
Retreating ice
Throughout much of the ice age, the Medicine Hat area was covered with a gigantic ice sheet. But occasionally, the ice retreated, paving the way for northern migrations of Pleistocene animals.
These northern migrations are far less understood than southern migrations in advance of ice sheets. It’s one thing scientists hope the Medicine Hat fossil, along with continuing work in other northern areas of the world, will shed light on.
“We’re starting to get a better picture of what lived in Canada in ages past. We see a fauna that is very similar to what we would see even in California,” Reynolds told the CBC. “We’re really just starting to figure out what the landscape looked like.”
