Why Wombats Are the Only Animals That Poop Cubes

In the animal kingdom, wombats hold a truly unique distinction: they are the only known creatures on Earth that produce cube-shaped poop. Not sort of square. Not vaguely boxy. Actual, stacking-ready cubes. Nature, it turns out, has a very strange sense of humor.

For years, scientists scratched their heads trying to understand the mechanics. Most of us learned in school that the shape of a container determines the shape of what comes out of it. But wombats do not have square plumbing. So how?

The answer, published in research that won an Ig Nobel Prize, lies in the wombat intestinal walls being unusually stretchy. As the last section of the digestive tract contracts, it does so unevenly, creating corners where rounded ones would normally form. The poop essentially gets sculpted into a cube on its way out. It is the most elaborate toilet engineering in the animal world, achieved entirely by accident.

As for why cubes? Wombats use their droppings to mark territory, and cubes do not roll away. Honestly, it is kind of brilliant. Leave it to a marsupial the size of a couch cushion to solve a geometry problem that stumped researchers for decades.