They are the only animals in the world that produce cube-shaped poop

Wombats are burrowing animals from Australia. What you might not know about these marsupials is that they are the only animals in the world that produce cube-shaped poop.

This peculiarity left scientists completely unable to give an answer to this phenomenon until now.

Patricia Yang, a researcher at the Georgia Institute of Technology, specialized in bodily-fluids, started to look into this topic more closely after hearing about it at a conference.

Mike Swinbourne, a wombat expert at the University of Adelaide in Australia, said that people had all sorts of theories about that, but the most popular is that wombats make cube-shaped poop to stack it for marking their territory. For them, the shape prevents poop from rolling away. But for Swinbourne this is a misconception.

He said that wombats poop where they need to poop, and they don’t try to stack it in a specific territory. For him, this particular shape is related to the dry environment where most of the wombats live. So when they have easier access to hydration, their poop is less cubic.

Moisture play a role, but it’s not the sole factor, because the digestive tract as well seems involved in this process.

To find the concrete answer to this phenomenon, Yard and her colleagues used wombat innards for their study. However, it wasn’t easy to find them, so she had to use roadkill wombats shipped from Australia.

At first, she thought they might have a square anus, but what she found to be important was how their intestine is stretched. The pressure from the intestine helps sculpt poop. To demonstrate that, Yang and her team expanded both wombat and a pig intestine with a balloon to compare their elasticities.

The pig intestine had a relatively uniform elasticity, which would explain its round poo. The wombat intestine, however, had a more irregular shape. Yang observed two distinct grooves which she believes helps shape wombat poop into cubes.

Swinbourne said that it was the first time someone has come up with a good biological and physiological explanation. However, Yang said there are still a host of questions to answer and the research is ongoing.

Source National Geographic