Tuesday, May 13, 2008

Bison

Bisons comprise two species of the genus Bison. One, commonly but incorrectly known as the buffalo, is the American bison. The other, the European species, is the wisent.

The bull of the American bisen, Bison, may weight more than 900 kg (about 2,000 lb) and stand more than 1.9 m (6 ft) high. The massive head and forequarters are covered with long hair, and the body slims down toward the hindquarter, which are covered with shorter hair. The female of the species is somewhat smaller. Both sexes have horns, but those of the male are more massive.

The bison was a principal resource of the Plains Indians, providing food, skims for shelter and boats, bones for tools and utensils, and "buffalo chips" (dung) for fuel. Few wild animals have undergone a more devastating encounter with humans. The grasslands from the Mississippi River to Rocky Mountains were home to 30 million bison when white settlers first arrived. These numbers were reduced to about 500 near the end of the last century, and then slowly increased to an estimated 35,000 to 50,000 on refuges and ranches today.

The European bison, or wisent, B. bonasus, may weigh up to 1,000 kg (2,200 lb) and stand more than 2 m (6 ft) high. It lack the shaggy coat of the American bison and has longer legs and a smaller head with longer horns. The wisent inhabits woodlands and feeds on grasses, ferns, leaves, and tree bark. At one time it ranged from western Europe to Siberia, but the destruction of forests led to its decline. On the verge of extinction in the early 1900s, the wisent is no longer endangered; captive breeding has been successfully used to increase the dwindling population.
The massive American bison is aggressive and easily angered. Before combat, a bull competes with other bulls in roaring.

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