When people mention “hoofed mammals,” we normally think of plant-eaters like deer and sheep. But, millions of years ago, some hoofed mammals were bloodthirsty carnivores. The most terrifying of all was probably Andrewsarchus, a gigantic predator that prowled the plains of Mongolia.
Only one good fossil of Andrewsarchus has been found: an enormous skull measuring 33 in (83 cm) in length.
Though scientists can’t be sure, the huge skull suggests the animal may have been twice as big as a grizzly bear, making it the largest carnivorous land mammal of all time.
■ When: 45–35 million years ago (Paleogene)
■ Fossil location: Mongolia
■ Habitat: Plains of Central Asia
■ Length: 13 ft (4 m)
■ Diet: Meat
Andrewsarchus may have looked like a giant wolf or bear. It had a long snout and immensely powerful jaws, with long, pointed canine teeth at the front for piercing flesh, and blunter teeth at the rear that may have been used to crush bones. Like a bear, it may also have eaten plant foods and scavenged from carcasses—its sheer size would have been enough to scare other predators away from their kills. Some scientists think Andrewsarchus is a close relative of whales, since they share a similar jaw structure.
DID YOU KNOW…?
Andrewsarchus is named after Roy Chapman Andrews (1884–1960), an American explorer and fossil hunter. Andrews led many expeditions to the Gobi Desert in Mongolia in the 1920s, where he discovered the dinosaurs Velociraptor and Protoceratops and the first known dinosaur eggs (search the article).
In 1923, he found a partial skull of Andrewsarchus—the only fossil, along with a few bones, that has been found. This priceless fossil is now on display at the American Museum of Natural History, in New York City.