Everyone poops, and it takes them about the same amount of time. A new study of the hydrodynamics of defecation finds that all mammals take 12 seconds on average to relieve themselves, no matter how large or small the animal. The research, published in Soft Matter, reveals that the soft matter coming out of the hind ends of elephants, pandas, warthogs and dogs slides out of the rectum on a layer of mucus that keeps toilet time to a minimum. “The smell of body waste attracts predators, which is dangerous for animals. If they stay longer doing their thing, they’re exposing themselves and risking being discovered,” says Patricia Yang, a mechanical engineer at the Georgia Institute of Technology in Atlanta. Yang, a doctoral student in the Woodruff School of Mechanical Engineering, worked on the study with David Hu, associate professor in the School of Biological Sciences and an adjunct associate professor in the School of Physics.