Wombats are short-legged marsupials, native to Australia. They are about one metre in length and weigh between 20 and 35 kg. They have small, stubby tails, rodent-like front teeth and powerful claws. A distinctive feature of wombats is their backward-facing pouch. The advantage of this is that, when using the teeth and claws for digging, the wombat does not gather soil in its pouch over its young.

They dig extensive burrow systems and, although they sometimes go out to feed on cool or overcast days, they mainly venture out in half-light or at night. As a result, they are not commonly seen. However, wombats do leave ample evidence of their presence in the form of soil disturbance and broken fences.

Wombats also leave other evidence: their distinctive cubic faeces. As they arrange these faeces 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 an advantage. The method by which the wombat produces them is not well understood, but it is believed that the wombat 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 pieces of faeces in a single night, and four to eight pieces each bowel movement.

In 2019 the production of cube-shaped wombat faeces was the subject of the Ig Nobel Prize for Physics, won by Patricia Yang and David Hu.

More Info: en.wikipedia.org