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Back in the day, bacterial diseases like dysentery were super deadly, but the nomadic people in northern Africa had long known about an effective, if hard to swallow, cure.

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Back in the day, bacterial  diseases were super deadly just ask anyone who’s ever  played The Oregon Trail. You have died of dysentery … again.

But for nomadic people in northern  Africa, dysentery wasn’t an issue. They’d long known about an effective, if hard to swallow cure: a  steaming ball of camel poop. This definitely sounds fake!

This incredible cure was  first noted by Western science in the late 1930s and early 1940s,  when soldiers stationed in Africa for World War II were dying  of dysentery in droves, while the local nomadic people seemed  mercifully free from the illness. Turned out they knew a  secret: that eating camel dung could prevent or cure dysentery. And not camel dung that was  dried and covered in chocolate or dissolved in herbal tea with  a little lemon or something to, you know, make it marginally more palatable.

No, it had to be camel dung  straight from the source. If it wasn’t fresh and warm, it wouldn’t work. A bit of scientific digging soon  revealed why this works: bacteria.

Specifically, camel dung  contains Bacillus subtilis a bacteria first identified on hay in 1835, though it’s now considered a soil microbe. It’s a cousin of the most notorious soil microbe,. Bacillus anthracis, which causes anthrax.

Luckily, this species is  kinder and gentler… to us. It’s a straight up monster to other microbes. Which is a big part of why it’s  so great for treating dysentery!

These bacteria secrete antibiotics  that knock out species like Shigella, the bacteria often responsible  for bacterial dysentery. In fact, genes for producing  antibiotics take up about five percent of the B. subtilis genome! Furthermore, studies suggest having these  bacteria in our gut can stimulate our immune system in ways that make us  better at fending off stomach pathogens.

And clinical trials have found  that they’re really helpful for treating diarrheal diseases. Now, given that B. subtilis  was first spotted on grass and is considered a common soil microbe, you might be wondering why it  had to be fresh camel poop. Can’t I eat some dirt or grass?

I don’t want to eat camel poop! Well, no one has specifically looked  at this, but the amount of B. subtilis in dung decreases over time,  while things like fungi increase. Also, the drier the bacteria get, the  less likely it is that they’ll settle in and reproduce when they do  end up in an animal’s gut.

So, maybe it’s simply a numbers  thing: it has to be fresh poop to make sure you’re getting a large enough dose. Fresh poop certainly has plenty of  bacteria in it, especially camel poop, because camels host a lot of  Bacillus in their digestive systems. Some scientists even think  these bacteria have adapted wto thrive inside the guts of animals.

And camels and other large herbivores  gain a lot from letting them live there. That’s because the bacteria produce enzymes that help the animals break down the  tough plant matter that they eat. Of course, nowadays, severe bacterial  dysentery is usually treated with a course of basic antibiotics  rather than a spoonful of camel poop.

Though, B. subtilis is still used as a probiotic. The helpful bacteria are grown  in labs and packed into capsules, no dung required. In fact, the species is so easy to grow,  it’s become an important model organism!

So it’s made all sorts of  contributions to science. Researchers have used it to learn  more about the fundamental processes of cells, like how they divide, as well  as the limits of bacterial survival. So not only has it saved lives, it’s  helped us understand life in general.

Now, despite its life-saving properties,. I’m guessing a fresh ball of  camel dung won’t go over so well as a gift this holiday season. Plus, where would you even get one?

That’s how you get banned from the zoo. Never fear, I have a gift  idea that’s easy to obtain and any science lover will appreciate! Over on we’ve just released a brand new SciShow Magnetic Words set!

It’s full of science-y words  curated by the whole SciShow team, like ‘Mitochondria,’ and  ‘Supermassive’ and ‘Quantum,’ and it comes packaged in a  handsome, SciShow-branded tin. You can use the set to announce important  scientific discoveries on your fridge, like: Researchers Have Found  Microscopic Butt Hair On Mars! And you can find it and  lots of other SciShow merch over on [♩OUTRO].