Columbian-Mammoth_250x150Columbian Mammoth


The Columbian mammoth is one of three species of mammoths that roamed North America during the Ice Age. The other two species were the wooly mammoth and Jefferson's mammoth. The largest Columbian mammoths were more than 13 feet (4 meters) high at the shoulders, and weighed as much as ten tons (nine metric tons). The tusks of the Columbian mammoth were up to 14 feet (4.25 meters) long, and its washboard-like teeth were well-suited for chewing grass.

American-Mastodon_250x150American Mastodon


Mastodons were distant relatives of mammoths and elephants. In North America, they were generally smaller than mammoths, standing about 7-8 feet tall at the shoulder. Unlike the washboard-like teeth of mammoths, mastodons had blunt, cone-shaped teeth that were probably used to chew leaves and pine needles in wooded areas.

Direwolf_250x150Dire Wolf


The dire wolf was a powerfully-built animal with sturdy legs, a broad head, and large teeth that may have been used to crush bone. Similar in appearance and size to the modern grey wolf, dire wolves were about five feet (1.5 meters) long and weighed about 110 pounds (50 kilograms). The range of the dire wolf extended to many parts of the Western Hemisphere. The remains of more than 3,600 dire wolves were recovered from the La Brea Tarpits in Los Angeles.

Sabertooth-Cat_250x150Saber-toothed Cat


As its name indicates, the saber-toothed cat had large canines that were up to 7 inches (18 centimeters) long. Saber-toothed cats were about the size of modern African lions, and had short, powerful legs, indicating that they probably hunted by ambushing their prey rather than chasing them down. Remains of saber-toothed cats have been found throughout North and South America.

Harlans-Ground-Sloth_250x150Harlan's Ground Sloth


Harlan's ground sloth was related to modern tree sloths, but were much larger, standing about 6 feet (1.8 meters) tall and weighing 3,500 pounds (1,600 kilograms). It had very large, powerfully-built limbs and claws. Harlan's ground sloth moved in an unusual manner, walking on the backs of its forefeet and the sides of its hind feet.

American-Lion_250x150American Lion


The American lion was slightly larger than the modern African lion. Their remains have been found from Alaska to northern South America. It was a formidable predator with a powerfully-built body and large canine teeth. The American lion probably hunted large prey, such as the ancient bison and Western horse, in open woodlands and grasslands.

Short-faced-bear_250x150Short-Faced Bear


The short-faced bear was the largest carnivore in North America during the Ice Age. It was taller than the brown (grizzly) bear, with longer, more slender hind legs, and a relatively short face that was more reminiscent of a lion rather than any living North American bear. In North America, the short-faced bear occupied the high grasslands west of the Mississippi, from Alaska to Mexico. In these areas, it probably preyed upon bison, deer, and horses.

Woodland-Muskox_250x150Woodland Muskox


The muskox is a herding animal that adapted to living in very cold conditions. It has long, dense, shaggy hair and large horns that curve down close to the head then turn upward near the tips. The extinct woodland muskox inhabited the plains and wooded areas. Males were considerably larger than females, standing 3 to 5 feet at the shoulder, and weighing up to an estimated 900 pounds.


Illustrations by Eric Parrish  © Denver Museum of Nature & Science

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