Prehistoric South America was a wild and exotic place. Stocky saber-toothed cats prowled around the grasslands, looking for equally stocky prey to take down. Giant sloths roamed the plains, tearing branches from trees that their future cousins would one day hang from. 10-foot killer birds, appropriately named “Terror Birds”, ran down small ungulates to sink their sharp beaks into.
And yet there was one particular prehistoric, South American mammal that had Charles Darwin himself stumped upon its discovery. This strange genus, called Macrauchenia had the long neck of a camel, the three-toed feet of a rhinoceros, and what may have been a tapir-like nose. The bizarre mishmash of traits had scientists stumped as to how to go about classifying the odd beast. When Charles Darwin first discovered limb bones and vertebrae fossils of the animal in 1834, at Port St Julian in Patagonia (Argentina), he originally speculated that the bones belonged to a mastodon. Four years later, scientist Sir Richard Owen wrote in a species description that the bones resembled a camel (taking the liberty of naming the creature, who’s name means “large llama”), but remained uncertain as to where exactly Macrauchenia fit in the mammal family tree. Recently, however, a rare DNA sample of the species was discovered, which was able to confirm the closest relatives of the Macrauchenia lineage.
Macrauchenia as seen in the BBC series “Walking with Beasts”.
By studying the DNA sample, researchers were able to deduce that the Macrauchenia was a distant relative of horses, tapirs, and rhinos, all members of a group called Perissodactyla. In a study published in Nature Communications, the researchers estimated that Macrauchenia branched out from Perissodactyla between 78 million and 56 million years ago.
Macrauchenia were grassland-dwelling herbivores that roamed South America, but went extinct along with many other megafauna around 12,000 years ago. Though their fossils were fairly plentiful in South America, scientists were unable to deduce just exactly what they were related to when going off of bones, much in part to the animal’s jumble of traits. Therefor, when a toe bone containing just enough Macrauchenia DNA to study was found in a cave in Southern Chile, a unique opportunity was presented to the scientists that found it.
Dr. Ross MacPhee, a curator at the American Museum of Natural History in Manhattan and one of the researchers who found the Macrauchenia toe bone, states that as tools used to study ancient DNA improve, we will be able to know more about the genomes of extinct mammals that inhabited warmer climates, where DNA deteriorates quicker.