Bison F.C.

Bison are large bovines in the genus ''Bison'' (Greek: "wild ox" (bison)) within the tribe Bovini. Two extant and numerous extinct species are recognised.

Of the two surviving species, the American bison, ''B. bison'', found only in North America, is the more numerous. Although colloquially referred to as a buffalo in the United States and Canada, it is only distantly related to the true buffalo. The North American species is composed of two subspecies, the Plains bison, ''B. b. bison'', and the wood bison, ''B. b. athabascae'', which is the namesake of Wood Buffalo National Park in Canada. A third subspecies, the eastern bison (''B. b. pennsylvanicus'') is no longer considered a valid taxon, being a junior synonym of ''B. b. bison''. References to "woods bison" or "wood bison" from the eastern United States refer to this subspecies, not ''B. b. athabascae'', which was not found in the region. The European bison, ''B. bonasus'', or wisent, or zubr, or colloquially European buffalo, is found in Europe and the Caucasus, reintroduced after being extinct in the wild.

While bison species have been traditionally classified in their own genus, modern genetics indicates that they are nested within the genus ''Bos,'' which includes, among others, cattle, yaks and gaur, being most closely related to yaks. Bison are sometimes bred with domestic cattle and produce offspring called beefalo or zubron.

Description

The American bison and the European bison (wisent) are the largest surviving terrestrial animals in North America and Europe. They are typical artiodactyl (cloven hooved) ungulates, and are similar in appearance to other bovines such as cattle and true buffalo. They are broad and muscular with shaggy coats of long hair. Adults grow up to in height and in length for American bisonGennady G. Boeskorov, Olga R. Potapova, Albert V. Protopopov, Valery V. Plotnikov, Larry D. Agenbroad, Konstantin S. Kirikov, Innokenty S. Pavlov, Marina V. Shchelchkova, Innocenty N. Belolyubskii, Mikhail D. Tomshin, Rafal Kowalczyk, Sergey P. Davydov, Stanislav D. Kolesov, Alexey N. Tikhonov, Johannes van der Plicht, 2016, The Yukagir Bison: The exterior morphology of a complete frozen mummy of the extinct steppe bison, ''Bison priscus'' from the early Holocene of northern Yakutia, Russia, pp.7, Quaternary International, Vol.406 (25 June 2016), Part B, pp.94-110
"American Bison", The National Wildlife Federation. and up to in heightSemenov U.A. of World Wide Fund for Nature, WWF-Russia, 2014, "The Wisents of Karachay-Cherkessia", Proceedings of the Sochi National Park (8), pp.23-24, , KMK Scientific Press and in length for European bison.Hendricks, K
"''Bison bonasus'', European bison"
Animal Diversity Web, 2013. American bison can weigh from around and European bison can weigh from . European bison tend to be taller than American bison.

Bison are nomadic grazers and travel in herds. The bulls leave the herds of females at two or three years of age, and join a herd of males, which are generally smaller than female herds. Mature bulls rarely travel alone. Towards the end of the summer, for the reproductive season, the sexes necessarily commingle.

American bison are known for living in the Great Plains, but formerly had a much larger range, including much of the eastern United States and parts of Mexico. Both species were hunted close to extinction during the 19th and 20th centuries, but have since rebounded. The wisent in part owes its survival to the Chernobyl disaster, as the Chernobyl Exclusion Zone has become a kind of wildlife preserve for wisent and other rare megafauna such as the Przewalski's horse, though poaching has become a threat in recent years. The American Plains bison is no longer listed as endangered, but this does not mean the species is secure. Genetically pure ''B. b. bison'' currently number only about 20,000, separated into fragmented herds—all of which require active conservation measures. The wood bison is on the endangered species list in Canada and is listed as threatened in the United States, though numerous attempts have been made by beefalo ranchers to have it entirely removed from the Endangered Species List.

Although superficially similar, physical and behavioural differences exist between the American and European bison. The American species has 15 ribs, while the European bison has 14. The American bison has four lumbar vertebrae, while the European has five. (The difference in this case is that what would be the first lumbar vertebra has ribs attached to it in American bison and is thus counted as the 15th thoracic vertebra, compared to 14 thoracic vertebrae in wisent.) Adult American bison are less slim in build and have shorter legs. American bison tend to graze more, and browse less than their European relatives. Their anatomies reflect this behavioural difference; the American bison's head hangs lower than the European's. The body of the American bison is typically hairier, though its tail has less hair than that of the European bison. The horns of the European bison point through the plane of their faces, making them more adept at fighting through the interlocking of horns in the same manner as domestic cattle, unlike the American bison, which favours butting. American bison are more easily tamed than their European cousins, and breed with domestic cattle more readily.

Evolution and genetic history

The bovine tribe (Bovini) split about 5 to 10 million years ago into the buffalos (''Bubalus'' and ''Syncerus