Species Three-Toed Sloth

Three-Toed Sloth

The three-toed sloths are tree-living mammals from South and Central America. They are the only members of the genus Bradypus and the family Bradypodidae. The four living species of three-toed sloths are the brown-throated sloth, the maned sloth, the pale-throated sloth, and the pygmy three-toed sloth.

Although similar to the somewhat larger and generally faster-moving two-toed sloths, the two genera are placed in different families. Recent phylogenetic analyses support the morphological data from the 1970s and 1980s that the two genera are not closely related and that each adopted their arboreal lifestyles independently. It is unclear from which ground-dwelling sloth taxa the three-toed sloths evolved; the two-toed sloths appear to nest phylogenetically within one of the divisions of Caribbean megalonychids, and thus probably either descended from them or are part of a clade that invaded the Caribbean multiple times. Both types of sloths tend to occupy the same forests; in most areas, a particular single species of three-toed sloths and a single species of the larger two-toed type will jointly predominate. Famously slow-moving, the sloth travels at an average speed of 0.24 kilometres per hour (0.15 mph).

Three-toed sloths are about the size of a small dog or a large cat, with the head and body having a combined length of around 45 cm (18 in) and a weight of 3.5–4.5 kg (8–10 lb). Unlike the two-toed sloths, they also have short tails of 6–7 cm (2–3 in), and they have three clawed toes on each limb.

They are frequently referred to as three-toed sloths, but all sloths have three toes; the difference is found in the number of fingers, meaning they are now more appropriately referred to as three-fingered sloths. This idea was first implemented by Judy Avey-Arroyo, cofounder of the world's only sloth sanctuary, but is now recognized in numerous publications as the correct terminology for these animals.