Wombats Are the Only Animals That Poop Cubes

The wombat is a stocky, burrowing marsupial from Australia that looks like it was designed by someone who had only ever heard a bear described secondhand. But forget the looks — what makes the wombat truly legendary is what it leaves behind.

Wombats produce cube-shaped droppings. Not sort-of-square. Not vaguely boxy. Actual cubes, stacked up like tiny biological building blocks. They are the only known animal on Earth capable of this geometric feat, and scientists were genuinely puzzled about how soft tissue could produce a rigid shape with corners.

The answer, confirmed by researchers who won an Ig Nobel Prize for their effort, lies in the wombat's intestines. Instead of being uniformly stretchy like most mammals', a wombat's intestinal walls have varying elasticity — stiffer in some spots, more flexible in others — which sculpts the waste into cubes as it moves through. Nature, apparently, has strong opinions about interior design.

Wombats use their cubic calling cards for communication, stacking them on rocks and logs to mark territory. The flat sides prevent the cubes from rolling away, which means evolution essentially invented non-slip poop. You really can learn something new every day.