There's plenty that archaeologists and paleontologists can learn from the bones and other artifacts left behind by ancient creatures and mankind's own ancestors. Researchers can figure out what they ...

Among the glistening dunes of New Mexico's White Sands National Monument, scientists have been taken aback by the discovery of footprints. The footprints belong to the extinct giant ground sloth, ...

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 ...

Paleontologist Thaís Pansani standing in front of a reconstructed giant ground sloth skeleton at the Smithsonian National Museum of Natural History. AP SAO PAULO (Associated Press) — Sloths weren’t ...

Long before today’s tree-dwelling sloths, a 4-ton giant roamed South America — and it may have stood and fought like a bear.

Ancient sloths ranged in size from tiny climbers to ground-dwelling giants. Now, researchers report this body size diversity was largely shaped by sloths’ habitats, and that these animals’ precipitous ...

Large animals started going extinct at the end of the Pleistocene, just as both climate change and a new predator — Homo sapiens — arrived on the scene. But despite humans’ brutal legacy of killing ...