Wombats: only animals that defecate in the form of cubes

Wombats are the only animals that poop in cubes. Now we know why. Scientists solved the mystery

Wombat, a marsupial native to Australia, is capable of producing perfectly cuboidal poop. It is the only animal known to defecate in this way.

In an effort to understand the geometric complexities of wombat droppings, a team of scientists from the University of Tasmania and the Georgia Institute of Technology studied him closely. To get to the bottom of the mystery, they dissected a wombat who died after being hit by a car.

What they found was that a wombat has two grooves in its intestines, where they are more elastic. The creature’s intestinal regions are able to expand and contract during the digestion process, which helps to create six-sided stool. “The wombat dissections show that the cubes are formed in the last 17 percent of the intestine,” wrote the researchers.

‘Using histology and traction tests, we found that the cross section of the intestine exhibits regions with a two-fold increase in thickness and a four-fold increase in stiffness, which, we hypothesize, facilitates the formation of corners by contractions of the intestine. ‘Surprisingly, the team did not stop there. They went ahead and created a mathematical model to simulate the passage of poop as it moves through the system.

As the wombat removes nutrients and water from its food, the resulting matter is compressed and shaped into a cube. It’s a bit like one of those garbage compactors that turn a car into a metal block. ‘Higher proportion of stiffness and greater number of Reynolds produce more square shapes’, wrote the team.

‘The corners arise from the faster contraction in the rigid regions and the relatively slower movement in the center of the soft regions. “These results may have applications in manufacturing, clinical pathology and digestive health.” The study’s findings were published in the scientific journal Soft Matter.


What is a wombat and what does it look like?

Wombats are muscular, short-legged quadruped marsupials, native to Australia.

They are about 1 m long with short, thick tails and weigh between 20 and 35 kg. There are three existing species and all are members of the Vombatidae family.

Mass: 20 – 35 kg
Speed: 40 km / h (maximum, when threatened)
Length: 100 cm
Scientific name: Vombatidae
Period of gestation: 20 – 21 days
Family: Vombatidae; Burnett, 1830