The ancestors of the American bison are the European bison of Eurasia. Subspecies that inhabit grasslands often form large groups, sometimes thousands of them migrate seasonally.

The head, neck and predecessor of the American bison have longer and denser hair than the European bison, have a shorter body and a smaller pelvis, and their hind body is not as developed as the European bison.

Generally speaking, the body of American bison is stronger than that of European bison, and its body and limbs are not as long as those of European bison.

A bill signed by US President Barack Obama in 2016, officially established as the national beast of the United States, is the largest mammal in North America and one of the largest bison in the world.

Relatively fierce, weighing up to 1 ton, with a pair of upward curved sharp horns on the head, even in the face of the most aggressive predators, do not flinch.

American bison and European bison are similar in appearance, but some changes have taken place in their habits. Bison live in large numbers in the Great Plains of the United States and Canada, from Lake Danu in the far north of Canada to Mexico in the south, and from eastern Oregon to the Atlantic Ocean.

Large herds of bison roam the Great Plains. They migrate south in winter and return to the north in summer, following a traditional route called the "bison trail". Bison like soil baths, rubbing their bodies on boulders and tree trunks to get rid of ectoparasites. They mostly look for food in the morning and evening and rest the rest of the time. When attacked by wolves, they can run at a speed of up to 60 kilometres per hour.

They are herbivores, feeding on tender grasses, twigs and leaves, and small shrubs. In winter, they dig up the thick snow to look for the plants buried below. The life span of wild bison is 18-22 years, while that of artificially bred bison is 35-40 years.

Among the known bison,6 species have become extinct. In addition to American bison, there are also European bison (B.bonasus) distributed in Eurasia.

Bison were once widespread in North America, stretching north to the Arctic Ocean in northern Canada, to northern Mexico in the south, to California in the west, and almost to New York on the coast of the Atlantic Ocean in the east.

They prefer open grasslands, thickets or semi-arid areas, and bison can be seen in sparse forests with low tree density. Although the American bison is not a typical plateau animal, some populations prefer to forage in the alpine belt in summer.

There are two subspecies of American bison: American forest bison (B.b.athabascae) and American prairie bison (B.b.bison).

They have an obvious geographical substitution: American forest bison live in the north (Canada and Alaska), while American prairie bison occupy the south. American forest bison are larger than American prairie bison, which helps to conserve heat in cold environments, according to Bergman's law