Few realize that the pronghorn (Antilocapra americana) is a Pleistocene survivor, a relict from the Ice Ages. It is a unique species and the only surviving member of the family Antilocapridae. The pronghorn was discovered by the Lewis and Clark Expedition, in what today is South Dakota.

For one small population, the endangered subspecies Sonoran pronghorn (Antilocapra americana sonoriensis), occurring only in Arizona and Mexico, their dying population went from almost 140 animals to 21 pronghorns during the drought of 2002. Now the numbers have moved above 100, at the Cabeza Prieta National Wildlife Refuge in Arizona.

See the article, “Deer-Like Animal Rebounds in Arizona”, for more details. The headline, btw, is terrible. Pronghorns are far from “deer-like.” And they are not antelopes, despite sometimes being called “pronghorn antelopes.” They are a very distinctive and ancient species.

Pronghorns are second only to the cheetah as far as being the world’s fastest land mammal.