Pronghorn | San Diego Zoo Animals & Plants

Although they’re often called antelope, pronghorn antelope, or American antelope, pronghorn are not true antelope. In fact, they’re unique enough to warrant their own taxonomic family, Antilocapridae. Pronghorn are native to North America and have no close relatives on any other continent. As such a significant North American species, they’ve been known by more than one hundred historic names in many languages.

The horns of a pronghorn help make them unique, as they share qualities of both horns and antlers. True antlers are made of bone and shed each year; true horns are made of compressed keratin and grow from a bony core but are never shed. The horns adorning a pronghorn have a sheath made of keratin and are shed yearly.

True horns have only one point, not the prongs or forks that antlers have. Yet a male (buck) pronghorn's horns can grow more than 15 inches (25 centimeters) long with a forward-facing prong. Hence their name: pronghorn. Female pronghorn (called does) also have horns, but they are much smaller. Pronghorn are the only animals in the world that have forked horns that shed each year!

A herd of sure-footed pronghorn dashing away looks like a group of cotton balls bouncing across their open, grassy, or desert habitat. Their tawny coats blend well with the dry landscape. A cotton-white rump patch serves as a beacon so the herd can stick together when fleeing. Their white underbelly and lower neck deflects heat rising from the ground. An outer layer of air-filled hairs helps them stay warm during winter. Come summer, they molt that coat and can erect their hair to stay cool.

Pronghorn have unique adaptations for spotting and evading predators such as wolves, foxes, coyotes, bobcats, and golden eagles. Pronghorn have large eyes to help them see predators. Scent communication allows them to mark territories and warn others of danger. Pronghorn bucks have nine scent glands and does have six. Glands beneath their ears help to mark territory during breeding time.

Glands on their rump are important when danger is near. If a pronghorn sees a predator, it releases an alarm odor from these glands while the white fur on its rump stands up. This sends a message by both sight and smell to let other pronghorn know of the danger. Pronghorn may defend themselves or their babies (fawns) by striking out with their hooves or by using their horns against a predator.

If a predator does manage to sneak up on a pronghorn, their amazing running skills come into action. Pronghorn are the fastest land mammals in North America. They can reach speeds of up to 60 miles (97 kilometers) per hour. This is not much slower than the fastest land mammal in the world, the cheetah. Yet pronghorn can maintain high speeds much longer than cheetahs can. A pronghorn's hooves have two long, pointed toes, cushioned to help absorb the shock when running at high speeds. Running with their mouth open allows pronghorn to take in lots of oxygen to fuel their running muscles. Although they are excellent runners, pronghorn are not good jumpers: if they come across a fence, they often go under it.