The Sloths Slow. French paresseux also mean lazy or similar. Sloths are almost helpless on the ground but are able to swim.
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Why are sloths so slow. It takes them 50 days to digest a fully leafed meal. All they do is slow down.
With so much effort exerted to extract a minimum of nutrients the sloths metabolism is amazingly slow- the slowest in the entire animal.
One of the main reasons these animals are so slow is so that they can move about unnoticed. A sloth hugging onto a tree branch. Their slowness permits their low-energy diet of leaves and avoids detection by predatory hawks and cats that hunt by sight. You probably wouldnt have a ton of excess energy to say sprint around the block.