The risky trip to the forest floor
Many three-toed sloths leave the safety of the canopy about once a week to defecate. They crawl down the tree, dig a small hole at its base, do their business, and climb back up. On the ground, their slow movement offers little protection from predators, making a routine bodily function a surprisingly exposed journey.
The timing reflects a slow digestive system. Sloths eat leaves, which provide little energy and are difficult to break down, so food moves through their gut slowly. Their infrequent bowel movements are part of a broader energy-saving way of life—not a sign that they can simply hurry through the task when danger appears.
Why leave the canopy at all?
Scientists do not have a single settled explanation for why sloths make the descent rather than defecating from above. One proposed explanation involves tiny moths that live in sloth fur: they breed in sloth dung, and their presence may help support algae growing in the coat. Sloths can eat that algae, so the trip may be tied to a small ecological cycle, though the details remain uncertain.
Whatever the full explanation, the animal’s weekly routine has a clear cost: it trades the canopy’s cover for a brief visit to the ground, where its slow pace makes escape difficult.
