It’s not considered polite to talk about it, but we all do it. Some of us are in and out so quickly that nobody would even ...

There are degrees of slothfulness, it turns out, even when it comes to sloths. And three-toed sloths may be the most slothful of them all: A species of the animal has a field metabolic rate that is ...

Everyone knows the tiger, the panda, the blue whale, but what about the other five to thirty million species estimated to inhabit our Earth? Many of these marvelous, stunning, and rare species have ...

Quick Take With sloths, the females are the ones responsible for mating calls. Three-toed sloth mating calls are often ...

A new analysis of three-toed sloths’ survival in the forests of Costa Rica offers two-fold insights for scientists hoping to aid the tree-dwelling critters. As Veronique Greenwood explains for The New ...

The charismatic and slow three-toed sloth is just one of many animals species that Smithsonian scientists study, from within our vast collections to live animals at our research centers and National ...

A rare pygmy three-toed sloth stirred an international controversy after officials of the Dallas World Aquarium caught and crated six of the creatures on Isla Escudo de Veraguas, an island off Panama.