Sloths comprise six species of medium-sized mammals belonging to the families Megalonychidae and Bradypodidae, part of the order Pilosa. They are arboreal residents of the rainforests of Central and South America. The sloth’s taxonomicsuborder is Folivora, while some call it Phyllophaga. Both names mean “leaf-eaters”; the first is derived from Latin, the second from Greek. Names for the animals used by tribes in Ecuador include Ritto, Rit and Ridette, mostly forms of the word “sleep”, “eat” and “dirty” from Tagaeri tribe of Huaorani, in Brazil sloths are commonly called “Bicho-preguiça” (“lazy animal”) because of slow movements related to their very low metabolism.

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