Most of us are familiar with sloths, the bear-like animals that hang from trees, live life in the slow lane, take a month to ...

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

A new fossil and DNA analysis traces how dozens of sloth species responded to climate shifts and humans. Just two small tree-dwelling sloths remain today.

An analysis of the sloth family tree suggests three different groups of the animals evolved to gigantic sizes in response to ...

A group of fossils of elasmosaurs—some of the most famous in North America—have just been formally identified as belonging to ...

A group of fossils of elasmosaurs -- some of the most famous in North America -- have just been formally identified as belonging to a 'very odd' new genus of the sea monster, unlike any previously ...

Working with local Indigenous people, biologist František Vejmělka spent six months surveying the creatures that live on ...