Scientists have figured out how wombats do cube poos, and say the discovery could help develop better medicines and machines.
Wombats, marsupials native to Australia, are the only creature in the world known to create a square anything, let alone poo.
"The first thing that drove me to this is that I have never seen anything this weird in biology - that was a mystery," said Patricia Yang of the Georgia Institute of Technology.
"I didn't even believe it was true at the beginning. I googled it and saw a lot about cube-shaped wombat poop, but I was skeptical."
So she decided to find out how, by dissecting wombats in Tasmania that had to be euthanised after being hit by cars.
Her team discovered the poo travels most of the way through their intestines like any other mammal, but at the very end of the 2.5-week journey - as it turns from liquid to solid - it gets pushed into a square shape. The walls of the intestine don't stretch as much along where the corners form, putting extra pressure and moulding the poo into strange 2cm-wide squares.
"We currently have only two methods to manufacture cubes: We mould it, or we cut it. Now we have this third method," said Dr Yang.
"It would be a cool method to apply to the manufacturing process - how to make a cube with soft tissue instead of just moulding it."
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But why do wombats make square poo? To show off, of course. Each night they produce dozens of little poop bricks and stack them to show off their territory. Wombats have poor eyesight, so the higher the better - and it's easier to stack squares than logs.
Newshub.
