Bear-Sized Snow Sloths? Meet Megalonyx, The Ice Age Giants That Lived Until 13,000 Years Ago

An Ice Age giant was tumbling around North America during the Late Pleistocene. About the size of a bear, it was actually a kind of enormous sloth that had evolved to thrive in freezing conditions.

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Known as Jefferson’s ground sloth (Megalonyx jeffersonii), it was named in honor of Thomas Jefferson who first presented its remains in 1797 (though we didn’t know exactly what it was back then). Now, you can see these ancient creatures in action in Prehistoric Planet: Ice Age.

This winter, the series will transport us millions of years beyond the extinction of the dinosaurs to an Earth gripped by ice. The series will premiere on Apple TV on November 26, but a new clip shows a playful side to Megalonyx as a trio venture out into the snow.

Megalonyx was enormous compared to its modern-day counterparts, measuring 2.4 to 3 meters (8 to 10 feet) in length and weighing a whopping 1,000 kilograms (2,200 pounds). It was a ground sloth so didn’t have to hurl its mass into the treetops, but despite their enormous size, M. jeffersoni fossils remain rare (though we did find a skull earlier this year).

As such, they remain one of the lesser-known megafauna of the Ice Age, many of whom will star in the new Prehistoric Planet. From the woolly mammoths everybody keeps trying to bring back to saber-toothed cats, dwarf relatives of elephants, and carnivorous kangaroos, each episode explores how life across the planet adapted to survive as Earth got hella’ icy.

The series comes from executive producers Jon Favreau and Mike Gunton, and was produced by BBC Studios Natural History Unit. Earthsounds’ Tom Hiddleston will be stepping into Attenborough’s shoes, with an original score by Hans Zimmer, Anže Rozman, and Kara Talve for Bleeding Fingers Music – a team famous for inventing new instruments to create a more immersive prehistoric sound.

So, if you’re in a part of the world that’s about to get plunged into winter, good news! You’ll have plenty of cold-tolerant pals to keep you company.