Three-toed sloth

The slowest mammal in the world

A sloth moves so slowly that green algae grows in its fur! This helps it hide in the forest. It sleeps 15 hours a day and climbs down from its tree once a week. A sloth can turn its head 270°. But in water it's a great swimmer!

The three-toed sloth (Bradypus variegatus) lives in the rainforests of Central and South America. Its speed is 4 m a minute: a diet of leaves gives so little energy that it has the slowest metabolism of any mammal, with a body temperature of 30–34 °C. Digesting a meal takes 30 days. Algae and moth species found only on sloths live in its fur — a tiny ecosystem. Nine neck vertebrae (most mammals have 7) let it turn its head 270°. Once a week it climbs down to the ground to poop — its most dangerous moment. It gives birth and sleeps hanging from a branch. In water it moves 3 times faster than on land.

Fun facts

• A sloth takes 30 days to digest a meal!
• A sloth's fur hosts green algae and moths found nowhere else.
• A sloth can turn its head 270° — almost all the way round.