Long before modern cities and borders, early humans shared the planet with enormous and often dangerous animals. Woolly ...

Add Yahoo as a preferred source to see more of our stories on Google. Harlan's ground sloth fossil skeleton excavated and displayed at the La Brea Tar Pits in Los Angeles. Larisa DeSantis A two-toed ...

Sometimes it nice to just kick back and take it slow. Really slow. So what if evolution had the same mindset, and decided to take its time before getting rid of some prehistoric creatures? What if the ...

(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 ...

Imagine a sloth. You probably picture a medium-size, tree-dwelling creature hanging from a branch. Today’s sloths – commonly featured on children’s backpacks, stationery and lunch boxes – are ...