Based on my time in academia, I would have thought funding for research was difficult to come by. Apparently, funding is no problem at the Georgia Institute of Technology, where researchers have been busy watching animals poo and examining said poo – all in the name of science, of course. Anything for science.
The study was led by Patricia Yang, whose interests include “the flow inside animal bodies including urination, defecation, and digestion.” I wonder if she’s single. After carefully examining twenty-three different varieties of mammal poop and spending hours watching the poor animals do their dirty business, Yang and her co-researchers claim their data shows that all mammals, small and great, defecate at nearly the same rate: around 12 seconds.
According to their data published in the appropriately-named journal Soft Matter, the researchers believe this consistency is due to the layers of mucus that line the intestines of all mammals:
Feces slide along the large intestine by a layer of mucus, similar to a sled sliding through a chute. Larger animals have not only more feces but also thicker mucus layers, which facilitate their ejection. Our model accounts for the shorter and longer defecation times associated with diarrhea and constipation, respectively.
Their data shows that 66% of animals spend between 5 and 19 seconds to defecate even though larger animals such as elephants can vacate up to a thousand times more volume than, say, a dog can. That means the larger the animal, the faster the fecal matter flows.
The researchers also had the stomachs (and noses) to test the densities and buoyancies of various mammal’s stool samples, sorting them into categories such as “floaters” and “sinkers” after tossing them in a special blender:
We also placed the feces in a device called a “rheometer,” a precision blender that can measure the properties of liquid-like and solid-like materials such as chocolate and shampoo. […] We learned that most elephants and other herbivores create “floaters” while most tigers and other carnivores create “sinkers.” Inadvertently, we also ranked feces from most to least smelly, starting with tiger and rhino and going all the way to panda.
Poor pandas. They just can’t catch a break. Of course, there is a standard deviation of 7 seconds in their data. That’s quite a bit of variance for a sample size of only 23. However, given that the body masses of mammals can vary by several orders of magnitude, it is rather surprising (I guess?) that the itsy-bitsy bowels of mice and the cavernous colons of elephants take roughly the same amount of time to vacate. Just wait until they learn to use smartphones. Those 12 seconds will become 20 Reddit-filled minutes.