Macrauchenia was a long-necked and long-limbed, three-toed South American ungulate mammal, typifying the order Litopterna. Macrauchenia had a somewhat camel-like body, with sturdy legs, a long neck and a relatively small head. Its feet, however, more closely resembled those of a modern rhinoceros, and had three hoofs each.
One striking characteristic of Macrauchenia is that, unlike most other mammals, the openings for nostrils on its skull were atop the head, leading some early scientists to believe that, much like a whale, it used these nostrils as a form of snorkel. Soon after, this theory was rejected. An alternative theory is that the animal possessed a trunk, perhaps to keep dust out of the nostrils. Macrauchenia’s trunk may be comparable to that of the modern Saiga antelope.
(via koryos)