Because only skulls and horns of this species have been found well preserved, the size of B. latifrons is currently not clearly known. Based on leg bones, the mass of B. latifrons has been estimated to be 25-50 percent larger than that of modern B. bison, making it undoubtedly one of the largest ruminants ever. The known dimensions of the species are on average larger than any extinct and extant bovids, including both the American bison and the European bison. Overall, it was probably around in length and stood about to tall at the withers. With an estimated weight of to, B. latifrons was one of the largest ruminants ever, rivaled in mass only by the modern giraffe and the prehistoric long-horned buffalo Pelorovis. The horns of B. latifrons measured as great as from tip to tip, compared with to in modern Bison bison.
Evolution
B. latifrons is thought to have evolved in midcontinent North America from B. priscus, another prehistoric species of bison that migrated across the Bering Land Bridge between 240,000 and 220,000 years ago. B. latifrons was one of many species of North Americanmegafauna that became extinct during the transition from the Pleistocene to the Holocene epoch. It is thought to have disappeared some 21,00030,000 years ago, during the late Wisconsin glaciation. The species was replaced by the smaller Bison antiquus as a part of adapting into the new continent when bison flourished in numbers; B. latifrons's immense size was likely a byproduct of "invasion" into North America due to the small population size within the new habitat. B. antiquus in turn evolved into the yet smaller Bison bison — the modern American bison — some 10,000 years ago by hybridization with new-coming Bison occidentalis which was smaller thanBison antiquus likely due to human hunting, but helped it to flourish in numbers in North America when Bison antiquus was already depleted by human intervention, and their modern offspring became smaller than Bison antiquus.
Habitat and behavior
A herbivore, B. latifrons is believed to have lived in small family groups, grazing in the Great Plains and browsing in the woodlands of North America. Paleontologists believe it preferred the warmer climes of what is now the United States, and fossils of the species have been found as far south and west as modern-day San Diego, California. The large, thick horns of the males are believed to have been employed as a visual deterrent to large carnivorous megafauna such as the saber-toothed cat and giant short-faced bear, and also to establish dominance in battle with other males for the right to mate. In 2014, the National Institute of Anthropology and History found remains of B. latifrons in Chilpancingo, Guerrero, southern Mexico.
