Wombats produce cube-shaped droppings.

Wombats are the only known animal to produce distinctly cube-shaped feces, and they use it for a purpose: wombats have poor eyesight and mark their territory by stacking these droppings on top of logs, rocks, and other elevated spots where they won’t easily roll away.

Researchers studying wombat intestines found the cube shape forms in the final stretch of the gut, where sections of varying elasticity and stiffness squeeze the waste into flat-sided segments before it’s excreted. A single wombat can produce dozens of these cube-shaped pellets in a night.