Three-toed sloths are bizarre animals who appear to live in slow motion. They are uniquely adapted for life in the trees -- they typically eat, sleep and even give birth while hanging upside down from tree branches.
Three species of three-toed sloth are described in the genus Bradypus. All are about the same size, reaching a little more than 10 pounds in weight; each feature three long, separate claws attached to their fused fingers and toes. Three-toed sloths are not muscular, they are able to hang upside down from tree branches via their three, long claws; even when shot by a poacher, sloths don’t release their grip -- they continue to hang on after death. Their dense fur actually grows in such a way that it points down when the animal is suspended. It is thought that this may be an adaptation that facilitates drying off after the frequent rainforest showers. Sloths are active day and night, and are known to use the sun to help thermoregulate.
Three-toed sloths are slow-moving creatures, though they are somewhat graceful when moving through the trees where they are adapted to live. The front limbs of three-toed sloths are longer than their rear legs, making them poorly equipped for terrestrial locomotion -- sloths are almost helpless on land. Sloths are very accomplished swimmers who move through the water by dog-paddling.
Three-toed sloths are found only in the Amazon rainforest and surrounding area. They are particularly associated with Cecropia trees. Sloths can occur at surprising densities in the rainforest; in some areas they represent two-thirds of the mammalian biomass. When not in Cecropia trees, sloths are known to sleep in the crowns of palm trees.
Sloths are folivores -- leaf eaters -- that eat little else. They have complex digestive systems, full of symbiotic microbes and bacteria that aid the animal in digesting the leaves. Leaves are hard to digest and contain few calories; this means sloths must be very economical about expending energy. To accomplish this, the metabolism of a sloth proceeds very slowly, and sloths maintain a very low body temperature for a mammal – usually under 93 degrees Fahrenheit. The digestive processes of sloths are so slow that a meal's digestion can take up to a month. Sloths urinate and defecate about once per week.
Sloths are so cryptic and slow-moving that they do not draw the attention of many predators. Their most important predators are Jaguars (Panthera onca), Harpy Eagles (Harpia harpyja) and humans. A sloth’s defensive repertoire is limited; aside from camouflage the only way a sloth can protect itself is by awkwardly swinging its clawed arms at a perceived threat.
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