[Daring Duos: Photos of ... knew why these tree-dwellers come down from the canopy to relieve themselves. "We hypothesized that this behavior sustains an ecosystem in the fur of sloths, which ...

Three-toed sloths descend from the trees once a week to defecate, providing a breeding ground for moths that live in the animals' fur and nourishing gardens of algae that supplement the sloths ...