All Mammals Take the Same Amount of Time to Poop, Scientists Find

Yes, everyone poops. Moreover, at least when it comes to mammals, everyone poops for about the same amount of time, according to a new study. The research, described in the journal Soft Matter and brought to our attention by the Science of Us, examined mammals as small as cats and as large as elephants, finding that they all took around 12 seconds to defecate.

The study examined elephants, giant pandas, and warthogs at the Zoo Atlanta, dogs at a park, the dimensions of feces and large intestines, and mathematical models to better understand how animals poop. The Georgia Institute of Technology researchers found that regardless of the animal’s total size, the mammals studied had feces that were double the length of their rectum, and whether that rectum was an inch-and-a-half long or almost 16 inches long, their feces took about 12 seconds to exit the body.

The researchers only studied animals with cylindrical feces (excluding rabbits, rodents, and ruminants like cows in the process), collecting stool samples from 34 zoo animals, seven farm animals, and two species of animals (unidentified) living at Georgia Tech. They also observed animals pooping at Zoo Atlanta firsthand and watched 19 different YouTube videos that featured animals doing their business.

Through their observations and theoretical calculations on the fluid mechanics of defecation, the researchers found that all animals exert the same amount of pressure while pooping. They also found that bigger animals had more poop to get rid of, but they also had thicker mucus layers lining the walls of their large intestine, which helps move the poop out of the body at a faster clip. Combine these two factors, and you get pretty consistent poop durations across the animal kingdom—12 seconds—despite the wide range of body sizes. (Constipation happens when the feces moving through the large intestine soak up that mucus layer. Think of it like trying to go down a waterslide that is completely dry.)

This study did not examine every animal on Earth, but the finding is in line with research on the other potty habits of mammals. Previous work—awarded an Ig Nobel Prize in 2015—found that all mammals pee for about the same amount of time (21 seconds). It’s evolutionarily plausible, too. Pooping makes it hard to run away from predators (a significant number of sloths die when they leave the treetops to poop at ground level, in fact) and a quick heave-ho of the bowels is safer than straining in one location for 20 minutes.

The researchers hope their study will be used for more than just satisfying the curiosity of colon obsessives, though. “By understanding the physics of defecation, we will provide not only new ideas for medical diagnostics, diapers, and incontinence products but also transport methods for the feces of humans, pets, and agriculturally important animals,” they write.