Macrauchenia: South American Herbivore

Macrauchenia was a swift, grazing herbivore that lived on the plains of South America during the late Miocene Epoch until the late Pleistocene Epoch. This curious hoofed animal has no living relatives today, and was the last of its kind before going extinct shortly after the fusion of North and South America. Resembling something between a camel and a horse, it was the equivalent of modern-day zebras on the South American pampas, where it was preyed on by large predators such as saber toothed cats. The first fossil of a macrauchenia was discovered by Charles Darwin and the uniqueness of the animal helped to support his theories of divergent evolution.

Like many other mammals on South America during the Cenozoic, macrauchenia is decidedly unique. Because South America was an island continent at this point, it was the equivalent of modern-day Australia, where evolution was able to diverge into interesting conduits not seen elsewhere on Earth. Macrauchenia was about ten feet long and five feet tall at the shoulder, lightly built with a small head and long legs. The shins and ankles of macrauchenia were extremely specialized to allow for tight turns at high speeds: a trait essential for eluding fleet-footed predators like big cats or giant flightless birds. It had rhino-like feet with three toes and also a short, prehensile trunk at the end of the head, probably used for rooting up vegetation that it ate. The nostrils were not located at the end of the trunk, but rather at the base of it, in front of the animal's eyes. This is a curious feature for a mammal, and it was once speculated that the animal used this configuration as a kind of snorkel for moving about in the water. This has since been rejected due to the proposed diet of the animal and its habitat.

It is likely that macrauchenia moved about in herds in order to protect both themselves and their young against South American predators. Judging from the size of the animal and also the presence of the prehensile trunk, these animals could have fed on grass, shrubs, or low branches in scrub forests on the edges of the plains.

After the invasion of predators from North America across the Isthmus of Panama into South America, macrauchenia was the last of a dying race of unique beasts. Although it was able to survive longer than many other indigenous South American herbivores due to its speed and success in herds, macrauchenia finally became extinct about 20,000 years ago.