Today, sloths are slow-moving, tree-dwelling creatures that live in Central and South America and can grow up to 2.5 feet long. Thousands of years ago, however, some sloths walked along the ground, ...

Sloths weren’t always the slow, tree-hugging creatures we know today. For millions of years, they came in a wild variety of ...

But as the planet cooled again, sloths began to bulk up. The largest ground sloths emerged during the Ice Ages. Big bodies ...

A new fossil and DNA analysis traces how dozens of sloth species responded to climate shifts and humans. Just two small tree-dwelling sloths remain today.

An analysis of the sloth family tree suggests three different groups of the animals evolved to gigantic sizes in response to cold and dry conditions ...

Giant sloths used to roam all over North America ... and whether they were climbers or walkers. Since sloth size was a major question, they measured museum fossils to estimate the sloth weight.

the size of sloths hardly changed at all for about 20 million years, irrespective of their preferred method of locomotion. Then something earth-shattering occurred. A giant wound opened up between ...

Giant sloths with razor-sharp claws and as large ... And, because the scientists were particularly interested in how sloths got their size, they estimated their weights by taking fossil measurements.