“There was this idea that humans arrived and killed everything off very quickly — what’s called ‘Pleistocene overkill,’” said Daniel Odess, an archaeologist at White Sands National ...

“There was this idea that humans arrived and killed everything off very quickly — what’s called ‘Pleistocene overkill,’” said Daniel Odess, an archaeologist at White Sands National ...

“There was this idea that humans arrived and killed everything off very quickly — what’s called ‘Pleistocene overkill,’” said Daniel Odess, an archaeologist at White Sands National ...

SAO PAULO (AP) — 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 ...

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 ...

At New Mexico's White Sands, researchers have uncovered human footprints dated to between 21,000 and 23,000 years ago, as well as similar-aged tracks of giant mammals. But some archaeologists say ...