A team of scientists from the Georgia Institute of Technology set out to investigate why Australia's wombats produce cube-shaped poop.
At the American Physical Society's Division of Fluid Dynamics 71st Annual Meeting, Patricia Yang, a postdoctoral fellow in mechanical engineering, and her colleagues presented their findings of the mechanics that lead to the marsupials' oddly-shaped droppings.
Wombats And Their Oddly-Shaped Poops
"The first thing that drove me to this is that I have never seen anything this weird in biology. That was a mystery," said Yang who studied hydrodynamics of fluids in the bodies of animals. "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."
In nature, anything cube-shaped is considered a rarity. For an item to be a cube — whether it be food or an architecture — it has to be molded or cut. Wombats are the only species known to produce cubes organically.
Wombats are territorial animals; they stack their oddly-shaped poop like bricks to mark their home ranges. Because the creatures have poor eyesight, they pile their stacks of poop on prominent places where it can easily be found.
Moreover, wombats use their poop to communicate with other wombats. The more poop is produced and compiled in one place, the better the chance it can attract other wombats to engage with and communicate.
That is why, for wombats, having cube-shaped poops that can be stacked and not roll away are very integral to their lives.
Why Are Wombats Poop Cube?
In a new study, Yang and colleagues sought the answer to the mystery of wombats' cube-shaped poop by looking at the animals' digestive tracts. They were able to obtain corpses of wombats that were euthanized following motor vehicular collisions and examined the animals' intestines.
They found that wombat excrement turns from liquid to solid near the end of the intestines where it does not stretch evenly. The last part allows the poop to be shaped into cubes.
"Wombat intestines have periodic stiffness, meaning stiff-soft-stiff-soft, along the circumference to form cubical feces," explained Yang to The Guardian.
Yang said that the information is useful for both fields of biology and engineering. The researchers hope that the study will make way for the development of a third process of manufacturing cube-shaped items more efficiently.