Ursid hybrid

In The Variation of Animals and Plants Under Domestication Darwin noted: In the nine-year Report it is stated that the bears had been seen in the Zoological Gardens to couple freely, but previously to 1848 most had rarely conceived.

In the Reports published since this date three species have produced young (hybrids in one case), ...[3]A bear shot in autumn 1986 in Alaska was thought by some to be a grizzly × black bear hybrid, due to its unusually large size and its proportionately larger braincase and skull.

Clinton Hart Merriam, taxonomist of grizzly bears, described an animal killed in 1864 at Rendezvous Lake, Barren Grounds, Canada as "buffy whitish" with a golden brown muzzle.

On 16 April 2006, a polar bear of unusual appearance was shot by a sports hunter on Banks Island in the Northwest Territories.

The DNA testing also spared the hunter the C$1000 fine for killing a grizzly bear, as well as the risk of being imprisoned for up to a year.

The guide leading the hunt, Roger Kuptana of Sachs Harbour in the Northwest Territories, was the first to note the oddities.

A blog columnist for the Seattle Post-Intelligencer suggested that more hybrids may be seen as global warming progresses and alters normal mating periods.

The Canadian Wildlife Service noted that grizzly-polar hybrids born of zoo matings have proven fertile.