Sometimes, for the sake of letting one’s imagination run around a bit, it may be advisable to indulge in a seemingly frivolous endeavor. In the sciences, these undertakings can sometimes result in the winning of an Ig Nobel Prize.
This year’s winner of the Ig Nobel in physics studied the “universal” urination time of mammals. The main conclusion of this paper is that mammals that weigh more than 3kg urinate for 21 13 seconds per session. I will not comment on the rather large error bars.
I reprint the abstract to the paper below:
Many urological studies rely on models of animals, such as rats and pigs, but their relation to the human urinary system is poorly understood. Here, we elucidate the hydrodynamics of urination across five orders of magnitude in body mass. Using high-speed videography and flow-rate measurement obtained at Zoo Atlanta, we discover that all mammals above 3 kg in weight empty their bladders over nearly constant duration of 21 ± 13 s. This feat is possible, because larger animals have longer urethras and thus, higher gravitational force and higher flow speed. Smaller mammals are challenged during urination by high viscous and capillary forces that limit their urine to single drops. Our findings reveal that the urethra is a flow-enhancing device, enabling the urinary system to be scaled up by a factor of 3,600 in volume without compromising its function. This study may help to diagnose urinary problems in animals as well as inspire the design of scalable hydrodynamic systems based on those in nature.
I present a translation of the abstract in my own language below:
We don’t know if humans and other mammals pee in the same way. Here, we study how both big and little mammals pee. We creepily filmed a lot of mammals (that weigh more than 3kg) pee with an unnecessarily high-speed camera and found that they all generally pee for 21 13 seconds. Large mammals can push more pee through their pee-holes and gravity helps them out a bit. It’s harder for small animals to pee because they have smaller pee-holes. Surprisingly, pee-holes work for mammals with a range of sizes. We hope this study will help mammals with peeing problems.
I genuinely enjoyed reading their paper, and actually recommend it for a bit of fun. Here are some of the high-speed videos (which you may or may not want to watch) associated with the paper.
Please feel free to experiment with your own “translations” in the comments.