Venture just outside Leiden in the Netherlands, and you'll spot a gigantic 115-foot-tall orange human figure looming beside ...

For a long time, scientists believed the first humans to arrive in the Americas soon killed off these giant ground sloths through hunting, along with many other massive animals like mastodons, ...

Sloths weren't always slow-moving, furry tree-dwellers. Their prehistoric ancestors were huge — up to 4 tons (3.6 metric tons) — and when startled, they brandished immense claws.Video above: ...

SAO PAULO — Sloths weren’t always slow-moving, furry tree-dwellers. Their prehistoric ancestors were huge — up to 4 tons — and when startled, they brandished immense claws. For a long time, scientists ...