A bear felled by an Idaho hunter in the Northwest Territories has provided proof of what many outfitters and biologists have suspected for years—that polar bear/grizzly hybrids ("polargriz") do exist.

Jim Martell shot the nearly all-white creature, believing it to be a polar bear. But when his guide got a closer look at it, he knew something was different. The bear had a slightly humped back and long claws like a grizzly, as well as brown fur around its eyes and in a few patches on its body.

Biologist Ian Stirling confirmed the guide's conclusion. Scientists have long suspected crossbreeding because the animals' mating seasons and habitats overlap.