Penguins that projectile poop


Adelie penguins may lack the opposable thumbs, big brains and Home Depot charge cards necessary to build themselves a working plumbing system. But that doesn't mean they are forced to poop where they live. Instead, these birds can launch their own feces out of their bodies like a Howitzer. OK, it's really not that dramatic, but the Adelie penguins do manage keep a clean nest.

Naturally, the first question Victor Benno Meyer-Rochow and Jozsef Gal had about this behavior in Adelies is "what kind of pressure do these birds generate when launching?" As the UK undergraduate who blogs as "SamW" noted, Adelie penguins are a protected species, so researchers aren't able to perform the invasive and potentially harmful observations required to directly measure the forces. Instead, Meyer-Rochow and Gal examined photographs.

When Adelies poop, they stand on the edge of their nests, their rear ends facing outward, and expel the fecal matter as far as possible. The researchers estimated the penguins' range at about 40 cm–not as far as the caterpillars, but still considerably better than the average human can do. Unlike humans, Adelies have a single "vent" for all bodily excretions (and sex)–the cloaca. Based on the size of the cloaca and the viscosity of penguin poo, Meyer-Rochow and Gal calculated the internal pressure at poo-launching at as high as about 600 grams per square centimeter (compare this to about 100 grams per square centimeter for humans). As SamW puts it, "no matter how hard you try to poop, a penguin can do it harder." The research was published in 2003 in Polar Biology.

You can read more about the delightfully odd pooping habits of animals—including a caterpillar that can shoot it's feces as far as 4.5 feet—in this article at Seed by Dave Munger.

Image: Some rights reserved by winkyintheuk