The North American bison, or buffalo, is the largest land animal in North America. A bull can stand 2 m high and weigh more than a tonne. Female bison are smaller than males. A bison has curved black horns on the sides of its head, a high hump at the shoulders, a short tail with a tassel, and dense shaggy dark brown and black hair around the head and neck. Another distinctive feature of the buffalo is its beard.