If all goes as planned, human feces should emerge in a cylindrical, sausage-like shape. But for wombats, “normal” is much, much different. In humans, lumpy poop in a similar shape means you need more fiber, hard lumps make for constipation, and goops mean you have diarrhea. Whatever mess your body is going through, however, you won’t see square-shaped poops floating in your bowl. That’s because only one animal on our good, green Earth has dumps that look a Rubix cube: the wombat.
While humans have long known that the feces of the Australian marsupial looks like Wendy’s hamburger patty, it hasn’t been understood exactly why. That’s where Patricia Yang, Ph.D., comes in: On Sunday at the American Physical Society’s Division of Fluid Dynamics 71st Annual Meeting in Atlantia, Georgia, Yang and colleagues presented the first study designed to investigate how the wombat creates cube-shaped poops. They discovered that it all stems from the wombat’s digestive process and the unique shape of its intestinal walls.