Extinct Long-horned Bison & Ancient Bison (Bison latifrons and B. antiquus) Fact Sheet: Physical Characteristics

Careful study of fossil bone or tooth anatomy yields much exact information about placement and strength of muscles, tendons, ligaments, nerves, and blood vessels. In rare cases, skin and hair impressions or actual skin or hair is preserved. Body weight is more difficult to gauge because fat leaves no impression on the skeleton.

General

• Bison latifrons: the largest and heaviest bison species to occur in North America
  • Long horns jut outward and curve gently upward
  • Not built for extended running and quick movement
• Bison antiquus: intermediate in size between B. latifrons and living bison
  • Straighter, shorter horns than B. latifrons
  • Agile, long-running

Teeth

•   All bison have 32 teeth, with only size differences between the species (McDonald 1981) (Meagher 1986).

Pelage

• Some indication of the length of hair may be seen in how much the orbital bones around the eyes protrude from the skull (Guthrie 1966)
  • Thick hairy faces could obscure vision; extending the eyes outward may solve the problem
  • Northern species of extinct bison (B. priscus) have orbits that protrude much further than more southern B. antiquus and B. latifrons; thus southern species may have been less hairy
• B. latifronsassumed to have had less hair on the front of the body and the head than other North American bison (McDonald 1981)
  • Animals with large horns tend to have less display hair (Geist 1971)

• Males larger and heavier than females
• Males have greater front-to-back diameter measurements of their horn cores than females (McDonald 1981)
• Males have shorter and wider frontal bones in their skulls than females (McDonald 1981)

• Horns are never shed
  
• Bison latifrons: Horn cores spanned 1.4 to 2.2 m (4.7 to 7.3 ft) (McDonald 1981)
  
• Bison antiquus: Horn cores spanned 1 m (3.3 ft) (Jefferson 2001)
• As in other bovid species, actual horns extended beyond the cores

Anderson (1984)
Geist (1971)
Guthrie (1966)
Meagher (1986)
McDonald (1981)