sloth slōth, slôth [key], arboreal mammal found in Central and South America distantly related to armadillos and anteaters. Sloths live in tropical forests, where they sleep, eat, and travel through the trees suspended upside down, clinging to branches with the powerful curved claws of their forelimbs and hindlimbs. Algae that grow on the hair impart a greenish color to the coat, which blends in with the foliage, but the algae are also eaten by the sloths. There is no tail.

The three-toed sloth (Bradypus) is about the size of a house cat, with a dense, furry coat and yellowish face. It has three toes on the front feet and five on the hind feet. In addition to algae, its main food is the leaves, buds, and stems of Cecropia, a tropical relative of the mulberry. The somewhat larger two-toed sloth (Choloepus) has very long hair. It eats a less restricted vegetarian diet. Sloths move sluggishly but can strike swiftly and powerfully if attacked. Huge ground sloths (see megatherium) are extinct forms.

Sloths are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Edentata, families Bradypodidae and Megalonychidae.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2023, Columbia University Press. All rights reserved.

See more Encyclopedia articles on: Vertebrate Zoology