What type of animals excrete cube-shaped feces?

Wombats are short-legged, muscular quadrupedal marsupials that are native to Australia. They are about 1 m (40 in) in length with small, stubby tails and weigh between 20 and 35 kg (44 and 77 lb). They are adaptable and habitat tolerant and are found in forested, mountainous, and heathland areas of southern and eastern Australia, including Tasmania.

Wombats leave distinctive cubic feces. As wombats arrange these feces to mark territories and attract mates, it is believed that the cubic shape makes them more stackable and less likely to roll, which gives this shape a biological advantage. The method by which the wombat produces them is not well understood, but it is believed that the wombat's intestine stretches preferentially at the walls, with two flexible and two stiff areas around its intestines. The adult wombat produces between 80 and 100, 2 cm (0.8 in) pieces of feces in a single night, and four to eight pieces each bowel movement. In 2019 the production of cube-shaped wombat feces was the subject of the Ig Nobel Prize for Physics, won by Patricia Yang and David Hu.