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

The apparent docility and friendliness of “smiling” sloths have made them tourist darlings, but have also put a target on their backs. The rise in trafficking of these animals led the governments of ...

Sloths appear defenseless, slow, and vulnerable in ecosystems filled with predators. Yet despite these disadvantages, they persist in environments where speed usually determines survival. Scientists ...

Woodland Park Zoo welcomed another animal into its tropical rainforest aviary. After five years, a new sloth has entered the villa. Fezzik, named after the character in “The Princess Bride,” is a ...