Ice Age Animals: Mammoths, Saber-Toothed Cats and More

What was the ice age?

Earth has had many ice ages. Strictly speaking, we are still in one that began about 2.6 million years ago, because ice sheets still cover Antarctica and Greenland. In everyday speech, though, “the ice age” means the last glacial period, from about 115,000 to 11,700 years ago, at the end of the epoch geologists call the Pleistocene.

At its coldest, between about 26,000 and 20,000 years ago, ice sheets several kilometers thick buried most of Canada, the northern United States, Scandinavia and the British Isles. So much water was locked up in ice that sea levels were about 120 m (400 ft) lower than today, and a dry land bridge called Beringia joined Siberia and Alaska.

South of the ice lay the mammoth steppe, a cold, dry grassland that stretched from Spain across Asia to Canada’s Yukon. It supported huge herds of grazing animals and the predators that hunted them. Scientists call large animals of this time megafauna, usually meaning species that weighed more than 45 kg (100 lb).

1. Woolly mammoth

The woolly mammoth (Mammuthus primigenius) is the symbol of the ice age. Males stood 2.7–3.5 m (8 ft 9 in–11 ft 5 in) at the shoulder and weighed about 4–8 tonnes, roughly the size of a modern African bush elephant. A thick coat of long guard hairs over a woolly undercoat, small ears and a short tail helped it save heat, and it may have used its long, curved tusks to clear snow from grass.

Its closest living relative is the Asian elephant. Frozen carcasses from Siberia, such as the baby mammoth Lyuba found in 2007, have even preserved skin, hair and stomach contents. Mammoths vanished from mainland Siberia around 10,000 years ago, but a dwarf population on Wrangel Island survived until about 4,000 years ago, after the Great Pyramid of Giza had been built.

2. American mastodon

The American mastodon (Mammut americanum) looked like a mammoth but belonged to a separate family that split from the ancestors of elephants at least 28 million years ago. It was shorter and stockier, with males about 2.75–3.05 m (9–10 ft) at the shoulder, and it browsed on twigs and leaves in forests and swamps rather than grazing. Mastodons lived across North America and survived until about 11,000 years ago.

3. Woolly rhinoceros

The woolly rhinoceros (Coelodonta antiquitatis) was about as big as today’s white rhinoceros and wore a shaggy coat and a long, flattened front horn. It grazed the mammoth steppe of northern Eurasia from Europe to Siberia but never crossed into North America. Ice Age artists painted it on the walls of Chauvet Cave in France. Its youngest reliable fossils are about 14,000 years old, and its closest living relative is the Sumatran rhinoceros.

4. Saber-toothed cat (Smilodon)

Smilodon, often called the saber-toothed tiger, was not a tiger at all. It belonged to an extinct group of cats that split from the ancestors of modern cats about 20 million years ago. The North American species, Smilodon fatalis, weighed 160–280 kg (350–620 lb), and the South American Smilodon populator reached 220–470 kg (490–1,040 lb), as heavy as the biggest tigers.

Its long, slender upper canines were too fragile for struggling prey, so it probably pinned large animals such as bison and camels with its powerful forelimbs before a precise killing bite. The La Brea Tar Pits in Los Angeles have yielded hundreds of Smilodon skeletons, and it is California’s state fossil. It died out around the end of the ice age.

5. Cave lion

The cave lion (Panthera spelaea) ranged from western Europe to Alaska and the Yukon. Ancient DNA shows it was a separate species from the modern lion, splitting off roughly 500,000 years or more ago. Cave paintings suggest males had little or no mane. Cave lions became extinct about 13,000 years ago. A related big cat, the American lion, lived farther south in North America.

6. Cave bear

The cave bear (Ursus spelaeus) of Europe and parts of Asia was as large as the biggest modern brown bears, with males averaging 350–600 kg (770–1,320 lb). Despite its size, chemical studies of its bones suggest it ate almost only plants. It hibernated in caves, where thousands of skeletons have been found. It died out about 24,000 years ago, during the coldest part of the ice age, long before most other giants.

7. Giant short-faced bear

The giant short-faced bear (Arctodus simus) of North America was one of the largest meat-eating land mammals that ever lived. Adults weighed 300–950 kg (660–2,090 lb), and a big male standing on its hind legs could reach about 3.4 m (11 ft). Once imagined as a fast-running super-predator, it is now thought to have been an omnivore that ate plants as well as meat. It vanished about 12,800 years ago.

8. Dire wolf

The dire wolf (Aenocyon dirus) of North and South America was about as big as the largest modern gray wolves, averaging 60–68 kg (132–150 lb), with heavier teeth and a stronger bite. A 2021 DNA study found that it belonged to an ancient American lineage that split from the ancestors of gray wolves millions of years ago. It hunted horses, bison and ground sloths and died out around 10,000 years ago.

In 2025, a biotech company announced three gray wolf pups with 20 gene edits meant to give them dire wolf traits. Independent experts, including the IUCN Canid Specialist Group, said they are modified gray wolves, not dire wolves.

9. Giant ground sloths

Ground sloths were relatives of today’s tree-dwelling sloths, such as the brown-throated sloth, but they lived on the ground and some grew enormous. Megatherium americanum of South America weighed about 3.5–4 tonnes, as much as an elephant, and could rear up on its hind legs to pull down branches. In North America, Megalonyx jeffersonii, first described by Thomas Jefferson, weighed up to about 1,300 kg (2,900 lb). Most ground sloths disappeared around 12,000 years ago.

10. Glyptodonts

Glyptodonts were giant relatives of armadillos from South America, protected by a domed shell made of hundreds of bony plates. Glyptodon grew up to about 2 m (6.6 ft) long, while Doedicurus averaged roughly 1,400 kg (3,100 lb) and carried a spiked club on its tail. A close relative, Glyptotherium, reached the southern United States. They died out at the end of the ice age, possibly helped along by human hunters.

11. Irish elk

The Irish elk (Megaloceros giganteus), also called the giant deer, was neither only Irish nor an elk; its closest living relatives are fallow deer. It stood about 2 m (6 ft 7 in) at the shoulder, and males carried the largest antlers of any known deer, spanning more than 3.5 m (11.5 ft) across. It ranged from Ireland to Siberia, and some survived in western Russia until about 7,700 years ago.

12. Steppe bison

The steppe bison (Bison priscus) was one of the most common grazers of the mammoth steppe, from western Europe to Alaska. It is shown in many cave paintings and is the ancestor of all North American bison, including the American bison. Unlike most of its neighbors, its descendants are still alive.

13. Diprotodon

Diprotodon, a relative of wombats and koalas, was the largest marsupial that ever lived. It stood about 1.8 m (5 ft 11 in) at the shoulder, measured more than 4 m (13 ft) long and may have weighed up to about 3,500 kg (7,700 lb). It roamed most of Australia in herds and died out around 40,000 years ago, along with every other Australian mammal heavier than 100 kg (220 lb).

Ice Age animals that are still alive

Not every ice age animal disappeared. Reindeer (called caribou in North America), musk oxen, saiga antelopes, wolverines, Arctic foxes, gray wolves and brown bears all lived alongside mammoths and survive today. Wild horses lived through the ice age in Eurasia but vanished from North America, where they evolved, until Europeans brought domestic horses back in the 1500s.

Why did ice age animals go extinct?

The cause of these extinctions is one of the longest-running debates in science. Around two-thirds of the world’s megafauna species disappeared in the Late Pleistocene, and the losses were heaviest in Australia and the Americas, where nearly every mammal over 1,000 kg (2,200 lb) died out. Africa and southern Asia lost far fewer species.

One idea, often called overkill, blames human hunters. The timing supports it: big animals vanished from Australia between about 50,000 and 40,000 years ago, after people arrived, and from the Americas around 13,000–10,000 years ago, as human populations spread across both continents. The other idea blames climate. As the ice melted, the cold, dry mammoth steppe turned into wetter forest, tundra and bog, shrinking the grasslands that mammoths, woolly rhinos and steppe bison needed.

Most scientists now think both causes mattered, in different proportions on different continents. In northern Eurasia, extinctions were spread over tens of thousands of years, and many are linked to climate swings. In the Americas, losses were sudden and closely matched the spread of people. The last mammoths on Wrangel Island, cut off by rising seas, survived thousands of years longer, a reminder that isolated populations can hang on long after their relatives are gone.