Wombats poop in perfect cubes

The wombat, a stocky Australian marsupial that looks a bit like a small bear, produces droppings with distinctly angular, almost cube-like edges — a trait seen in no other known animal.

The secret is in the gut: the final stretch of a wombat's intestine has alternating sections of stiffer and more elastic wall tissue, which molds the passing waste into flat edges instead of the round shape typical of mammals.

Wombats put these cubes to deliberate use: they stack them on rocks and logs as territory markers — the cube shape means they don't roll off the surface the way an ordinary round dropping would.

It sounds like a biological joke, but scientists studied the mechanics of a wombat's intestine seriously enough that the findings ended up being applied in materials engineering, informing how soft materials are molded.