# Bison antiquus

Bison antiquus is an extinct species of bison that lived in North America during the Late Pleistocene from over 60,000 years ago until around 10,000 years ago. Bison antiquus was one of the most common large herbivores in North America during this time period. It is the direct ancestor of the living American bison.

## History of discovery

The first described remains of Bison antiquus were collected at Big Bone Lick, Kentucky in Pleistocene deposits in the 1850s and only consisted of a fragmentary posterior skull and a nearly complete horn core. The fossil (ANSP 12990) was briefly described by Joseph Leidy in 1852. Although the original fossils were fragmentary, a complete skull of an old male was discovered in southern California and were described as a new species, B. californicus, by Samuel Rhoads in 1897, but the species is considered synonymous with B. antiquus.$^{:759–760}$ Since the 19th century, several well preserved specimens of B. antiquus have been discovered in many parts of the United States, Canada, and southern Mexico.

## Distribution

Bison antiquus is known from fossils found across North America south of the Laurentide Ice Sheet (whose southernmost extent is around the modern United States-Canada border), ranging from southern Canada (southern Alberta and Ontario) in the north, and Washingon State and California in the west, southwards to Southern Mexico and eastwards to South Carolina and Florida.

## Description

Compared to the living American bison (Bison bison). B. antiquus was considerably larger and had longer limbs, with the upper limbs being more slender while the lower limbs were more robust. The skull was also somewhat more elongate and less domed than that of American bison. It reached up to 2.27 m (7.4 ft) tall, 4.6 m (15 ft) long, and a weight of 1,588 kg (3,501 lb), with an average of around 800 kg (1,800 lb). The horns were also considerably larger than those of living American bison and differed somewhat in shape, being on average 87 centimetres (2.85 ft) across tip to tip, but could be as much as 106.7 centimetres (3.50 ft) across.

## Ecology

Unlike living American bison, which are almost exclusively grazers, dental wear analysis suggests that Bison antiquus was a variable mixed feeder (both browsing and grazing) with an adaptable diet depending on geographical location, with diets varying from strict grazing to mixed feeding. Bison antiquus was likely preyed upon by large carnivores, which may have included the American lion (Panthera atrox), the sabertooth cat Smilodon fatalis, and dire wolves (Aenocyon dirus).

## Evolution

Around 195,000-130,000 years ago, the steppe bison (Bison priscus) crossed the Bering Land Bridge into North America. In North America, B. priscus evolved into the large long-horned Bison latifrons, which then gave rise to B. antiquus sometime prior to 60,000 years ago. B. antiquus became increasingly abundant in parts of midcontinent North America from 18,000 until about 10,000 years ago.

## Relationship with humans

A number of sites document the exploltation of Bison antiquus by Palaeoindian groups, such as those associated with the Clovis culture and the later Folsom tradition. The Folsom tradition in particular is thought to have been reliant on hunting bison.
One of the best educational sites to view in situ semifossilized skeletons of over 500 individuals of B. antiquus is the Hudson-Meng archeological site operated by the U.S. Forest Service, 18 mi (29 km) northwest of Crawford, Nebraska. A number of paleo-Indian spear and projectile points have been recovered in conjunction with the animal skeletons at the site, which is dated around 9,700 to 10,000 years ago. The reason for the "die-off" of so many animals in one compact location is still in conjecture; some professionals argue it was the result of a very successful paleo-Indian hunt, while others believe the herd died as a result of some dramatic natural event, to be later scavenged by humans. Individuals of B. antiquus of both sexes and a typical range of ages have been found at the site.
B. antiquus may have been hunted by Clovis people in North and South Carolina, based on blood residue from Clovis points. At Jake Bluff in northern Oklahoma, Clovis points are associated with numerous butchered Bison antiquus bones, which represented a bison herd of at least 22 individuals. At the time of deposition, the site was a steep-sided arroyo (dry watercourse) that formed a dead end, suggesting that hunters trapped the bison herd within the arroyo before killing them. Other arroyo trap sites include Cooper in northwest Oklahoma and Badger Hole also in Oklahoma, which are associated with Folsom points. B. antiquus remains exhibiting butchery marks have been found at Ayer Pond on Orcas Island in Washington State.

## Extinction

The living American bison (Bison bison) is suggested to have evolved from Bison antiquus in central North America at the very end of the Pleistocene. The last populations of B. antiquus became extinct during the early Holocene, around 10,000 years ago. Likely intermediates between the species are referred to as Bison "occidentalis".