Scientists have finally discovered why wombat poop is cube-shaped
Our species has documented the habits and traits of other life on this planet for thousands of years. Now, as our technology grows even more advanced and comprehensive, we can learn even more about the natural world. However, that doesn't mean there aren't plenty of mysteries that we haven't quite understood yet.
While these mysteries may refer to things such as the life that exists too deep in the ocean for our equipment to record, some are a lot sillier - but nonetheless bewildering. For instance, no one has figured out until now, why exactly wombats produce cube-shaped waste.
The wombat, a large relative of the koala native to Australia, produces around 80 to 100 cubes each night. The solitary and nocturnal animal lives in underground burrows during the day, sleeping an average of 16 hours per day, before it heads out to forage for vegetation to eat. It uses its cube-shaped dung to mark its territory, dropping piles of the stuff near its burrows, but even with all that material to work with - scientists have been puzzled over exactly how they keep their cube shape.
Recently, a team of scientists claimed that they have figured out why they have this unique trait. Led by the Georgia Institute of Technology's Patricia Yang, this research team have said that they have figured out the digestive processes that lead to this strange process.
"In the built world, cubic structures are created by extrusion or injection molding, but there are few examples of this feat in nature," the study's abstract reads. At the 71st Annual Meeting of the American Physical Society's Division of Fluid Dynamics in Atlanta on Sunday, they presented their findings, revealing that they had examined the digestive tracts of wombats found in Tasmania, Australia.
The wombat takes between 14 and 18 days to digest its food, and researchers found that it is towards the end of the process, when the faeces moves into the final 8% of the intestine, that it changes into solid matter. This long digestive tract allows it to absorb the most nutrients and water from its food, and it is here that they take on the shape of cubes, measuring around two centimetres.
"The local strain varies from 20% at the cube's corners to 75% at its edges," the team said. "Thus, the intestine stretches preferentially at the walls to facilitate cube formation."
After they inflated the intestines with a long balloon, the team discovered that the intestine walls stretch unevenly with horizontal ridges, which allows for the formation of these cube shapes.
On the other hand, the final section of the large intestine is relatively smooth, which means the cubic shape is not changed before it is released. The fact that the faeces is so dried-out and highly-compacted, means that no further moulding takes place from this point.
While this all may sound like a frivolous discovery, the research team believe that these findings could have implications beyond the mystery itself, as it could potentially provide some insight into modern manufacturing techniques.