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As a SciShow viewer, you can keep building  your STEM skills with a 30 day free trial and 20% off an annual premium  subscription at Brilliant.org/SciShow. You probably don’t spend a lot of  time thinking about dung beetles.

But maybe I can convince you that there’s  a lot more to dung beetles than just poop. Because they’re helping you  out, yes you specifically, by doing everything from improving  agricultural yields to fighting climate change. So put a clothespin over your nose and let’s  get to know the little guys a little better. [♪ INTRO] There are a few distinct types of dung  beetle and they live all over the word, often much closer to home than you may expect.

The first are rolling dung beetles,  the classic ones you might picture from nature documentaries or  ancient Egyptian iconography. As you’d guess, they create  dung balls and roll them. These balls are known as brood balls, and are actually an offering, usually  by the male dung beetle to the female.

They serve as both food for her, and food  for her offspring, as long as it’s accepted. We also have tunnelers. They’re dung beetles that create tunnels of  varying depth directly below the dung pile itself to feed dung into for either themselves,  their mate or their offspring.

If you’ve ever lifted up a cowpatty and  seen pockmarks in the ground below, that’s the work of tunnelers. Other varieties are ones that  simply live in the dung pile itself, and some are even kleptoparasites, meaning they steal the dung of other  individuals as their entire survival strategy. That’s not the flattering picture I  promised you, but all of these guys are performing some seriously important  services by digging around in poo.

For one thing, dung beetles can  regenerate poor quality soil. Areas in South Africa once used for mining  have soil that is infertile, heavily compacted, and lacking in useful nutrients and minerals. In short, you’d struggle to grow anything there.

But when researchers gathered up dung beetles  from farmland and added them to this type of soil, those soils grew significantly more  plant life, and had more nutrients as well. That means land that has been made effectively  barren by things like unsustainable farming practices or fossil fuel extraction could be  partially restored just by adding dung beetles. Helping us repair our mistakes, or just make  use of land for stuff like feeding people.

On top of this, dung beetles also  increase water absorption in the soil. Tunnelling dung beetles drill  down into the soil to lay eggs, and the young break it up  even more when they emerge. That makes the soil more  porous, so it holds more water.

The tunnelers can get down to over  100 centimeters, and in just 48 hours, dung beetles can create an  effect that lasts for six months. More water being absorbed means  less runoff and potential flooding, and it’s better for plant communities too. Handy thing to have on a warming planet.

In areas that are predicted  to become a lot more arid, dung beetles are predicted to help  soil absorb more rain when it comes. And for areas that have excessive rainfall,  the same effect can help prevent flooding. All that churning of the soil leads  to a lot of mixing in the sediment.

But of course, dung beetles don’t just dig  and burrow; they also bury their brood balls. All this digging and dung mixing don’t just result in plants being able to grow  where they couldn’t before. It can often lead to more, larger,  and healthier plants as well.

Look… it’s fertilizer. Nitrogen is an important nutrient for plants, and it can be lost to the atmosphere thanks  to ammonia gas escaping from livestock dung. When dung beetles bury it, that  nitrogen stays in the soil instead.

Plants grown with dung beetles are  more nutritious and productive. In fact, a few studies have  suggested that dung beetles can actually outperform chemical  fertilizers in improving plant yields. Many of these studies have been  done in laboratory settings, often with a single species  of dung beetle or plant.

But dung beetles often function at  their best in big, complex communities with multiple roles played by multiple species. Which means the effect in the wild  could actually be much more significant. Herbivore dung isn’t just full  of chewed up leaves and grass.

It’s also full of seeds. Dung beetles help out by  burying balls full of seeds. Seeds like to be planted, I guess, but in practice this protects them from predators or pathogens.

It also helps by dispersing the seeds. Dung beetles don’t tend to roll their  balls much further than 15 meters or so, but that’s enough to space seeds  out so they’re not overcrowded. The area of soil a dung beetle selects may also  end up being better for the plant to grow in than whatever random spot the dung was dropped in.

So far, ok, the idea of dung beetles being  good for plants isn’t THAT far out there, but lemme hit you with another one. They may also help reduce  greenhouse gas emissions. A study from Finland published in 2016 found that dung beetles in cow pastures can reduce methane.

Cows are known to produce methane  as a side effect of their digestion, and since methane is a powerful greenhouse gas,  this makes cattle farming pretty high-impact. One way this methane is produced is from  cow patties as they sit around the pasture. The dung beetles break up the cow patty  and expose its contents to oxygen, which causes it to give off less methane.

Unfortunately, this benefit is held back  by the fact that many developed countries raise cattle at least partially  indoors where dung beetles can’t help. However, in countries where cattle are grazed  more on pasture and live primarily outdoor lives, the effect could be a lot more important. There’s a whole continent that stands as a  case study for the ability of dung beetles to clean up our messes.

And that’s Australia. Because, of course it is. Cattle and sheep aren’t native to Australia,  and when they were introduced in the 1700s their waste quickly started to build up,  polluting waterways and smothering pasture.

So 53 species of dung beetles were introduced,  of which 23 survived and stuck around. They transformed the soil, encouraged nutrient  flow, and limited the influence of pests. And they didn’t even ask for anything in return.

Except poo. Absolute legends. So, sure.

Dung beetles aren’t really appealing or exciting. But it could be argued that they work harder  than humans do at cleaning up human messes. So thanks, little dudes.

I’ll just… appreciate you from over here. Way over here. It’s incredible that these tiny bugs can  help us with humanity’s largest problem.

But it makes sense if you think  of the minuscule molecules that get out of balance in the climate crisis. Nitrogen, methane, and the other stuff beetles  work with are just molecules in the end. And to help make the idea of a  molecule a little less abstract, there’s a Brilliant course called “Molecules”  made in partnership with MinuteEarth.

Brilliant is an interactive online  learning platform with thousands of lessons in science, computer science, and math. And they’re supporting this SciShow video! They work with a diverse set of experts to teach  you all of that STEM stuff, from researchers at MIT, Princeton, and Stanford, to expert  communicators like MinuteEarth and Kurzgesagt.

All of those big brains come together to  make the world a little more understandable. And they’re giving these learning tools to  you for free for your first 30 days of use! After that, you can take 20% off an  annual premium Brilliant subscription by clicking the link in the description down  below or going to Brilliant.org/SciShow. [♪ OUTRO]