Sloths are arboreal mammals noted for slowness of movement and for spending most of their lives hanging upside down in the trees of the tropical rainforests of South America and Central America. The six species are in two families: two-toed sloths and three-toed sloths. The sloth is so named because of its very low metabolism and deliberate movements. This is an evolutionary adaptation to their low-energy diet of leaves, and avoid detection by predatory hawks and cats who hunt by sight.
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