This might be a personal question, but have you ever thought about how long it takes you to pee?

No, me neither. Nor had Danny Hoyland at West Bremer Radio.

But David Hu, an mechanical engineer from Georgia Institute of Technology, has found that for mammals larger than rats, the time it takes to empty their bladders is roughly the same: 21 seconds.

So that means an elephant (18 litres of urine) takes as long as a Great Dane (1.5 litres) and a cat (5 milllitres).

It all comes down to the urethra (the tube that connects the bladder to the outside world) predictably increasing its width as it gets longer. As it gets longer, the effects of gravity also increase and help push the urine out.

This is all very interesting, but what could this have to do with anything useful, I hear you ask. Well, it could help engineers to develop better methods of draining large areas of water.

So now I bet you’ll be sneaking a timer into the loo to see how you compare.

Original story: Most Mammals Take 21 Seconds to Pee, Regardless of Their Size

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