Related content: "26 April 2017 Most mammals big or small take about 12 seconds to defecate"
https://www.newscientist.com/article/21 ... -defecate/
Quote:
Everyone poops, and it takes them about the same amount of time. A new study of the hydrodynamics of defecation finds that all mammals with faeces like ours 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 and colleagues filmed elephants, pandas and warthogs at a local zoo, and one team member’s dog in a park, as they defecated. All these animals produce cylindrical faeces, like we do, and this is the most common kind among mammals. Though the animals’ body masses ranged from 4 to 4,000 kilograms, the duration of defecation remained constant.
Hmm, "duration of defecation" ... try to say that three times fast.Quote:
Using a rheometer – a device that measures the way fluids flow under applied force – Yang found that faeces are shear-thinning, which means they have lower resistance the faster they’re deformed. That’s why dog poop feels slippery when you step on it.
Based on animals at the Atlanta Zoo, they found that on average, animals take in about 8 per cent of their body mass in food, and expel 1 per cent of body mass in faeces.
Their observations fed into a mathematical model that can predict defecation times for various problems within the digestive system. “If it’s taking far longer than 12 seconds, I’d say you should go see someone about it,” she says. “But you can’t count the newspaper time.”
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30 Aug 2017, 10:55 am
