Hyenas are more familiar today as creatures of the savanna, but on some level, they make sense as Arctic inhabitants, living among large, trunked mammals and big cats, just as modern hyenas live among elephants and lions. “It’s really easy for us to sort of fall into a trap of thinking that these habitats were a lot like the African Serengeti,” says Grant Zazula, the Canadian government’s official Yukon paleontologist and a co-author of the paper. “And in some ways, they were.” After all, the desert and the tundra are both extreme, inhospitable climates, with no forests for big herbivores to hide in. Still, the Yukon during the Pleistocene era was dark four months of the year and very cold. Even though modern-day packs hunt at night, hyenas living in Ice Age Canada would still have depended on some very different adaptations—for a start, some thicker, lighter-colored fur would have been in order.
Based on other specimens collected in the past century, scientists know that Chasmaporthetes had longer, more evenly proportioned legs than modern-day hyenas, along with a shallower skull, which would have made for faster, more sustained running and a wolflike appearance. According to Julie Meachen, a paleontologist at Des Moines University, the hyenas would have hunted and scavenged on animals such as musk oxen and caribou in the Arctic tundra. They might also have chowed down on bison and horses in refugia between the glaciers, where things were relatively temperate and “a little more vegetated.”