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

Researchers in Costa Rica have unearthed fossils from a mastodon and a giant sloth that lived as many as 40,000 years ago, ...

Scientists have analyzed ancient DNA and compared more than 400 fossils from 17 natural history museums to figure out how and why extinct sloths got so big. Most of us are familiar sloths, the ...

Sometimes it nice to just kick back and take it slow. Really slow. So what if evolution had the same mindset, and decided to ...

WICHITA, Kan. (KWCH) - A prehistoric discovery near Hays is shedding some new light on a giant ground sloth species that lived more than 10,000 years ago. A study published Monday in the peer-reviewed ...

In a discovery that challenges long-standing views of prehistoric life, scientists have uncovered vast underground tunnels beneath Brazil and Argentina that appear to have been excavated by ...

In 1991, a skateboarder discovered 1.5-million-year-old giant ground sloth fossils in Wilmington, North Carolina. Scientists from the Smithsonian determined the fossils belonged to two different ...

(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.) Imagine a sloth. You probably picture a medium-size, tree-dwelling creature hanging ...

Ancient sloths lived in trees, on mountains, in deserts, boreal forests and open savannahs. These differences in habitat are primarily what drove the wide difference in size between sloth species.

SAN JOSE, Costa Rica — Researchers in Costa Rica have unearthed fossils from a mastodon and a giant sloth that lived as many ...