Pronghorns are true American natives, found nowhere else in the world.
The pronghorn has exceptionally keen vision complemented by excellent hearing and sense of smell. Both sexes have horns, but the female's are only tiny spikes and are rarely pronged as are the twelve to eighteen-inch horns of the male. This sheath is made up of a stiff, hair-like substance. Pronghorns are the only animals in the world who shed their horns annually. The outer sheath of the horn falls off each fall and grows back by the following summer.