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). 

There are three extant species and they are all members of the family Vombatidae. They are adaptable and habitat tolerant, and are found in forested, mountainous, and heathland areas of south-eastern Australia, including Tasmania, as well as an isolated patch of about 300 ha (740 acres) in Epping Forest National Park in central Queensland.

Wombats dig extensive burrow systems with their rodent-like front teeth and powerful claws. One distinctive adaptation of wombats is their backward pouch. The advantage of a backward-facing pouch is that when digging, the wombat does not gather soil in its pouch over its young. Although mainly crepuscular and nocturnal, wombats may also venture out to feed on cool or overcast days. 

They are not commonly seen, but leave ample evidence of their passage, treating fences as minor inconveniences to be gone through or under, and leaving 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 intestine stretches preferentially at the walls. 

The adult wombat produces between 80 and 100, two-centimetre (0.8 in) pieces of feces in a single night, and four to eight pieces each bowel movement.

According to en.wikipedia