The extinct mammals were about five times larger than a grizzly bear–and filled caves with their poop.

Explore how ancient sloths evolved in size, from small climbers to massive ground dwellers, shaped by shifting climates and ...

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.

Paleontologist Thaís Pansani standing in front of a reconstructed giant ground sloth skeleton at the Smithsonian ... shows the widespread decline of American megafauna starting around the same ...

For a long time, scientists believed the first humans to arrive in the Americas soon killed off these giant ground sloths through ... the widespread decline of American megafauna starting around ...

For a long time, scientists believed the first humans to arrive in the Americas soon killed off these giant ground sloths through ... the widespread decline of American megafauna starting around ...

Peering into dark recesses of the cave, I wonder what might have caused ... Given previous extinctions of megafauna such as Darwin’s giant sloth, and humanity’s inability to protect current ...

For a long time, scientists believed the first humans to arrive in the Americas soon killed off these giant ground sloths through ... the widespread decline of American megafauna starting around ...