Enlarge (credit: Brandon Weeks) In 2015, mechanical engineers at Georgia Institute of Technology calculated that all mammals take about the same amount of time to empty their bladders: roughly 21 second of urinating. With the finding, they won an Ig Nobel prize—parody Nobel awards given to comical, yet interesting research. In pursuit of further toilet tidbits—or perhaps another Ig Nobel—the researchers have now squeezed out a mathematical model of the hydrodynamics of pooping.