The pronghorn (Antilocapra americana) is not a true antelope but in a family by itself (Antilocapridae). It is native only to North America.
The pronghorn is the only North American big game animal that has branched horns, from which its name derives. Pronghorns have true horns—derived from hair—not antlers. The horns have an outer sheath of fused, modified hair that covers a permanent, bony core. Pronghorns shed the hollow outer sheath each year in October or November and grow a new set by July. Both bucks and does have horns, but doe horns are shorter and more slender. Adult pronghorns stand 3 feet (90 cm) high at the shoulders. Bucks weigh about 110 pounds (50 kg); does weigh about 80 pounds (36 kg).
Pronghorns have a bright reddish-tan coat marked with white and black. The buck has a conspicuous black neck patch below the ears, which is lacking on the doe. At a distance, their markings break up the outline of their body, making them difficult to see. Their white rump patch is enlarged and conspicuous when they are alarmed. The flash of white serves as a warning signal to other pronghorns and is visible at long distances.