Archive for July 4, 2020

The Joy of Penguin Faeces

Posted in The Universe and Stuff with tags , , , on July 4, 2020 by telescoper

Last night my attention was drawn to an important article on the ArXiv in the domain of biophysics. The title is Projectile Trajectory of Penguin’s Faeces and Rectal Pressure Revisited*.

Here is the abstract:

We discuss a trajectory of penguins’ faeces after the powerful shooting due to their strong rectal pressure. Practically, it is important to see how far faeceses reach when penguins expel them from higher places. Such information is useful for keepers to avoid the direct hitting of faeceses. We estimate the upper bound for the maximum flight distance by solving the Newton’s equation of motion. Our results indicate that the safety zone should be 1.34 meters away from a penguin trying to poop in typical environments. In the presence of the viscous resistance, the grounding time and the flying distance of faeces can be expressed in terms of Lambert W function. Furthermore, we address the penguin’s rectal pressure within the hydrodynamical approximation combining Bernoulli’s theorem and Hagen-Poiseuille equation for viscosity corrections. We found that the calculated rectal pressure is larger than the estimation in the previous work.

That is amusing enough (though admittedly the English isn’t great) but the diagrams are an absolute joy!

*In case you’re wondering about the “revisited” at the end of the title, the authors of the present work present a critique of earlier work by Meyer-Rochow & Gal (2003) in which “the projectile trajectory of the faeces is not taken into account”. This previous paper was awarded the Ignobel Prize in 2005.

One should not pooh-pooh research on this topic and now that we have got to Number Two I for one hope for the speedy production of further outputs in this area.