India, Sept. 22 -- Wombats are well-known for their obstinacy, having short bodies and the unique ability to use their hard backsides to defend themselves against predators that might be after them. However, the feature that stands out when it comes to wombats is their droppings, which are the only known cube-shaped feces. The mystery behind this feature was not solved until now because nobody could understand how a tube-like soft intestine can shape feces into such geometric forms.

Patricia J. Yang of the Georgia Institute of Technology presented initial findings on wombat feces at the American Physical Society's Division of Fluid Dynamics meeting in 2018. The conference abstract lists Yang, Miles Chan, Scott Carver and David L. Hu as t...