Being confronted with a pack of wolves is bad enough, but if you happened to be in Alaska some 12,000 years ago, things would be much, much worse. Back then, the icy forests were patrolled by a sort of super-wolf. Larger and stronger than the modern gray wolf, this beast had bigger teeth and more powerful jaws, built to kill very large prey.

This uber-wolf was discovered by Jennifer Leonard and colleagues from the University of California, Los Angeles. The group were studying the remains of ancient gray wolves, frozen in permafrost in eastern Beringia, a region that includes Alaska and northwest Canada. These freezer-like conditions preserved the bodies very well, and the team found themselves in a unique