Antilocapra – Pronghorn

Pronghorns are the fastest land mammals after the cheetah but can maintain their speed for much longer

It is the only surviving member of the family Antilocapridae, a testament to the pronghorn’s resilience and adaptability through millennia. The pronghorn is distinct from other hoofed mammals in North America in its physiological characteristics, ecological role, and behavioral patterns.

One of the most striking features of the pronghorn is its horns, which give the species its name. Unlike the permanent horns found in other ruminants, pronghorn horns are composed of a keratin sheath that grows over a bony core. These horns are forked and can be shed annually, a unique characteristic among the animal kingdom. Males typically have longer horns than females, with both branches of the fork well-developed, whereas females may have shorter, simpler horns or none at all.

Pronghorns exhibit a preference for open terrains, such as grasslands and deserts, where their exceptional eyesight serves as a critical survival tool. Their eyes are large and positioned on the sides of their head, providing a wide field of vision that helps detect predators from great distances, up to 5 kilometers (3 miles) away. This remarkable visual acuity is complemented by their speed, making pronghorns one of the fastest land animals in the Western Hemisphere. They can sustain speeds of 55 miles per hour (88 km/h) over short distances and maintain speeds of 30-40 miles per hour (48-64 km/h) for longer stretches, an adaptation that allows them to outrun predators.

Pronghorns are also noted for their social behavior. They live in mixed-sex herds for much of the year, though males may establish territories and gather harems of females during the breeding season. Both visual signals, such as body postures and the display of white fur patches, and olfactory signals from specialized scent glands facilitate communication within and between pronghorn groups. These glands produce a “danger scent” when threats are detected, alerting the herd to potential danger and facilitating a coordinated escape strategy.