The American Bison (Bison bison) has a long history that, like a significant number of animals, starts on another continent; there is an extant European Bison (Bison bonasus) distantly related to and far more rare than the American Bison. The fossils we are going to discuss are the members of the family that arrived or thrived in North America prior to the appearance of what we would recognizably call the American Bison. Three extinct species of the genus Bison were endemic to North America prior to the appearance of Bison bison, the American Bison, in the fossil record. These species were, in order, B. latifrons, B. occidentalis, and B. antiquus. They range from approximately 240,000 years ago when B. latifrons is thought to have initially crossed the Bering Land Bridge into North America to approximately 5,000 years ago when B. antiquus appears to have gone extinct. The three species are not identical and B. latifrons is actually quite impressive, measuring in at 2.5 meters (8.2 ft) and estimated to have tipped the scales at 2,000 kilograms (4,400 lb); that is almost as tall as a modern Asian Elephant. The horns of B. latifrons measured approximately 213 centimeters (84 in) from one tip to the other. Bison bison measures in with horns approximately 66 centimeters (26 in) from tip to tip. Bison occidentalis is less well-known, but it is smaller than B. latifrons and its horns, also much smaller, pointed toward the rear of its skull, rather than the front. Bison antiquus was nearly as tall at 2.27 m (7.5 ft) but much lighter at 1,588 kg (3500 lb) and with horns noticeably smaller, though pointing forward, that measured approximately 1 m (3 ft) wide.
|Photo from North Dakota Department of Mineral Resources. B. latifrons exhibit at the North Dakota Heritage Center|