Finally. An answer to one of life’s great mysteries: why wombat poop is cube-shaped.
We know—you were really on the edge of your seat about this. But it is curious that wombats are the only creature on Earth that poop in cubes. Scientists didn’t know the reason for this unusual ability, though some theorized that the unique shaped made it possible for wombats to stack their droppings to mark their territory.
Wombats do use their droppings to mark territory, but they don’t handle and stack their scat like Lego bricks (at least, not when humans are watching). Still, cube-shaped nuggets may be convenient in that they don’t roll as easily, but that still doesn’t answer the question of how wombats make the cubes.
Patricia Yang, researcher at the Georgia Institute of Technology, had a hard time believing that wombat droppings were cubes. When she learned it was true, she had to know why.
There are a couple reasons for the cubes. First, wombats live in dry environments, and they need to absorb as much moisture as possible from their food. Mike Swinbourne, wombat expert at the University of Adelaide in Australia, told National Geographic that wombats in captivity sometimes have less cubic droppings because water is more readily available. Dry droppings can more readily form and hold more rigid shapes.
But that’s not the only factor at play—other animals have dry droppings that are round. Patricia Yang took a look at wombat intestines (collected from roadkill), and found that the way their intestines stretch helps form cubed feces. Yang and her fellow researchers stretched wombat intestines using balloons, and they found that while the pig intestines they tested had uniform elasticity, wombat intestines have more varied elasticity. As the waste gets pushed through the final part of the intestine, the stiffer parts of the intestine help shape the droppings into cubes.
Wombats usually drop 80 to 100 individual droppings per night, and they prefer to leave them on top of rocks, logs, or on other high places. They’re used to mark territory and help wombats navigate at night. Because of their shape and dry texture, they stack well and don’t lose their shape.
Wombats are the only creatures to leave cube-shaped droppings, and now the world knows how they do it. But now that the secret is out, it seems wombats will still retain the corner market on cube poop.
Katie Taylor started writing in 5th grade and hasn't stopped since. Her favorite place to pen a phrase is in front of her fireplace with a cup of tea, but she's been known to write in parking lots on the backs of old receipts if necessary. She and her husband live cozily in the Pacific Northwest enjoying rainy days and Netflix.