Ursid hybrid
An ursid hybrid is an animal with parents from two different species or subspecies of the bear family ("Ursidae"). Species and subspecies of bear known to have produced offspring with another bear species or subspecies include black bears, grizzly bears and polar bears, all of which are members of the genus "Ursus". Bears not included in "Ursus", such as the giant panda, are expected to be unable to produce hybrids with other bears. Note all of the confirmed hybrids listed here have been in captivity (except grizzly × polar bear), but suspected hybrids have been found in the  wild. A recent study found genetic evidence of multiple instances and species combinations where genetic material has passed the species boundary in bears (a process called introgression by geneticists). Specifically, species with evidence of past intermingling were (1) brown bear and American black bear, (2) brown bear and polar bear, (3) American black bear and Asian black bear. Overall, this study shows that evolution in the bear family ("Ursidae") has not been strictly bifurcating, but instead showed complex evolutionary relationships. All the "Ursinae" species (i.e., all bears except the giant panda and the spectacled bear) appear able to crossbreed. Brown  × black bear hybrids. In 1859, a black bear and a European brown bear were bred together in the London Zoological Gardens, but the three cubs did not reach maturity. 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), ... 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. DNA testing was unable to determine whether it was a large American black bear or a grizzly bear. Intercontinental brown bear hybrids. Although Eurasian brown bears and North American Brown bears are isolated, they are listed as a single species, so technically mating between the two sub-species is not hybridization, even though it cannot possibly occur in the wild. However, cross-breeding between the European brown bear and the North American grizzly bear has occurred in Cologne, Germany. Brown  × polar bear hybrids. Kodiak × polar bear hybrids. "Kodiak" or "Kodiak brown" is a term now applied to brown bears found in coastal regions of North America. In the far north these bears feed on salmon and often attain especially large size. "Alaskan brown" is sometimes used for Alaskan bears, but the main distinction is how far the bear is found from the coast. "Grizzly bear" is the term used for the brown bear of the North American interior. Grizzly × polar bear hybrids. The grizzly bear is now regarded by most taxonomists as a variety of brown bear , "Ursus arctos horribilis". 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. This is considered to be a natural hybrid between a grizzly bear and polar bear. On 16 April 2006, a polar bear of unusual appearance was shot by a sports hunter on Banks Island in the Northwest Territories. DNA testing released 11 May 2006, proved the kill was a grizzly×polar bear hybrid. This is thought to be the first recorded case of interbreeding in the wild. The bear was proven  to have a polar mother and a grizzly father. 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 hunter had bought a license to hunt polar bears; he did not have a license to hunt grizzly at that time. The animal had dark rings around its eyes, similar to a panda's, but not as wide. It also had remarkably long claws, a slight hump on its back, brown spots in its white coat, and a slightly indented face  — the nasal "stop" between the eyes which polar bears lack. The guide leading the hunt, Roger Kuptana of Sachs Harbour in the Northwest Territories, was the first to note the oddities. Several names were suggested for this specimen. The Idaho hunter who killed it, Jim Martell, suggested "polargrizz". The biologists of the Canadian Wildlife Service suggested "grolar" or "pizzly", as well as "nanulak", an elision of the Inuit "nanuk" (polar bear) and "aklak" (grizzly or brown bear). Both "grolar" and "pizzly" were used by the Canadian Broadcasting Corporation in widely distributed stories. Presently, though the mating seasons overlap, the polar  bears' season begins slightly earlier than the grizzly bears'. 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. Grizzly bears have been sighted in what is usually polar bear territory in the Western Arctic near the Beaufort Sea, Banks Island, Victoria Island, and Melville Island. A "light chocolate colored" bear, possibly a hybrid, is reported to have been seen with polar bears near Kugluktuk in western Nunavut. Ursid hybrid