(narrator) Out here in the wild west of the Serengeti, it's no place for the weak.

You might strike it rich, but watch your thorax.

There's bandits everywhere, ready to steal what you worked hard for.

I'm not talking about gold.

I'm talking about poop.

[whip cracks] What is happening?

I can explain, guys.

I brought a story today about one of my all-time favorite subjects.

You're not going to believe what this is.

Oh, my God.

I also brought a story about one of my all-time favorite subjects.

Wait.

Same time?

One, two, three, extreme senses.

Extreme senses.

How long did it take you to practice that one?

(Western accent) I was born this way.

(normally) No, wait, you mean counting to three?

I've been doing that for a long time.

[gentle music] Emily, I think you're gonna like this for a completely different reason because of where our story starts.

It's amazing-- in an ecosystem as rich and diverse as the Serengeti, you know what the most important valuable resource in this entire ecosystem is?

Well, it's right here.

Steaming hot pile of fresh elephant dumg.

I'm intrigued.

It's a beautiful sight.

It is.

I mean, how fresh do you think this is?

(Joe) Within the hour.

Yeah, do you reckon?

Ew.

What is he... Squishy.

No.

What?

Okay, we'll talk about that later.

I have a little hand sanitizer in my bag.

I mean, I can tolerate a lot of gross stuff, but even I have my limits.

(Joe) So the number one cool thing that we saw that day was this awesome bull elephant.

And the number two coolest thing we saw that day was that number two.

I mean, elephants, impressive at both ends, I got to tell you.

But we also weren't the only ones who found that special present.

I mean, this is swarming.

It's swarming with flies, ants.

Like, every bug in the Serengeti, I feel like, has found this pile of poop.

(Jahawi) And it was incredible just how quickly they came onto this pile.

(Joe) Within, like, minutes of this hitting the ground, they were here.

I mean, if you consider just how nutrient-rich it is, and in almost a broken-down form, the dung beetles-- they'll make a nice ball of it and kind of roll it off to their burrow and--and lay their eggs in it.

You can just roll with us.

Ey... Are you in the dung beetle fan club?

Yeah, dung beetles are the best.

They're the best.

Can confirm.

(Joe) This is like a--like a stinky gold rush finding a pile of poo like this.

I mean, there's water and nutrients, and this is crucial stuff in a place like this, where competition for resources can be so fierce, right?

These beetles-- they battle brutally on this bounty from a bowel.

It's a brutal bowel bounty beetle battle.

There's battles going on on this dung pile of beetles fighting other beetles to get the best spot with the freshest, wettest elephant poop.

I mean, who wouldn't want to fight over this?

We should watch our backs.

There might be other people out here with cameras that want this pile of elephant poop.

That's exactly--oh, yeah.

You know, this is valuable stuff.

(Joe) So these dung beetles scoop their shovel-like heads through this stinky motherlode, gathering armfuls of poop like farmers harvesting their crops and then using their incredibly muscular legs to mold and mash it into a ball perfect for rolling home.

But you got to get home fast, because other beetles-- they want that dung.

Watch out for beetle dung bandits.

(Joe) So here is the problem that these dung beetles have to solve.

How do they find the quickest route home in the straightest line?

You know, that's a really good question because we're surrounded by tall grass.

So how do you know which way to go?

(Emily) Yeah, I mean, to us, grass is only knee or waist-high, but to a dung beetle, it's like being stuck in the forest.

There are no landmarks.

I mean, I would be totally lost.

Humans are actually famously bad at this.

You drop people in the wilderness with no navigational aids, they'll just walk around in circles.

Figuring a straight path home is really hard unless-- Obviously, they carry teeny tiny compasses.

Actually...

But I mean, if you kind of---if you look up, there's some things that you can use to navigate.

Like a universal compass.

Exactly.

(Joe) So their eyes-- they're super tiny, right?

But they are highly specialized for picking up the position and the height of the Sun in the sky.

And it gets even better.

If the sun is hidden, like it's behind a cloud or something, their eyes can even pick up on patterns of polarized light, like, how light waves spin, and they can even use that for navigation.

That's gotta be the most unique astronomy skill I've ever heard.

Poop navigation.

Poop navigation.

Well done, dung beetles, poop navigators, smelly astronomers.

They push for a little bit, head down, legs kicking.

Then they pop up on top of their dung ball, they do this little dance, turning around to sense the pattern of light.

Got their directions, back down, push, push, push, pop up, dance, navigate, push, dance, navigate, and just keep repeating that all the way home.

It's so cute, and they're very good at it.

(Trace) I never thought I would say this about a beetle that literally spends its whole life pushing poop around, but that's pretty cute.

They dance like me at a wedding.

(Joe) And these beetles are super strong.

I mean, those dung balls can weigh like 50, 100 times their body weight.

They don't care.

Push it right up the mountain.

They never skipped leg day... or exoskeleton day.

What's the equivalent of 100 times our body weight?

If we were like pushing around a couple of trucks?

But now tell me, so you've got these species that--that are active during the day, but you also have species of dung beetle that are active at night.

Ooh, good question.

Jahawi turning the tables on you, Mr.

Scientist.

It is a good question.

So there are other species of dung beetles that are only active at night.

I mean, dung harvesting is a 24-hour business, okay?

But these beetles--this is going to blow your mind.

They're doing the same thing, but they're just using different cues from the sky.

They actually see the Milky Way.

They use the band of the Milky Way through the sky as a way to orient themselves back to their burrows.

Absolutely incredible.

Wait, can they actually see the stars?

So their eyes are probably too small to actually see the individual stars, but get this: scientists actually put dung beetles inside of a planetarium, and they realized that they were using the band of the Milky Way in the sky to navigate home.

(Trace) I would not want to clean the carpet at the planetarium after that visit.

But I would want to narrate that show.

Do you think they're astrologists?

Reading the constellations?

Yeah.

Poop is in Leo today.

I'm more of a Gemini poop guy.

Scientists have done all kinds of hilarious and creative things to figure this out.

I mean, blindfolding dung beetles, like putting mirrors around them.

Build them planetariums.

This is--this is crazy.

I want to see the blindfold.

Honestly, that's amazing.

They're--I mean, they're like, a little like index card cutouts they, like, tape to their heads.

It's so ridiculous.

Do they need any interns?

Because I am there.

Sign her up.

We know it might be a little weird, but we've uncovered something so cool out of it.

I mean, this is the only insect that I know of that can see our galaxy.

I mean, that's wild.

But I think it's a really cool connection there.

Evolution freaking rules.

(California accent) Totally does.

Extreme.

(accented) Dude, evolution.

It's sweet.

All I need in life is a big ball of poop and some sick waves.

I don't have any brothers, but I feel like working with you guys is the closest I've ever been to having an experience.

I'm s--I'm sorry.

I feel kind of, like-- like, touched by that.

They may live in poop, but these are amazing little creatures.

Galaxy-gazing beetles?

Incredible, but they aren't the only bugs that can sense things at the edge of what is physically possible.

These bugs are straight fire.

Do--are the kids still saying that, Trace?

I don't know if that's what the kids say-- I'm not cool-- but fire is cool.

And to understand what I'm talking about, we got to go to Berkeley, California.

It's not often that you are alone in a giant stadium all by yourself.

Some say it's haunted.

Echo!

So in the early 1940s, this stadium was here.

It looked exactly the same as it does now.

Still had the bleachers, still had the field, still had the trees up around it.

And out of those trees is where our story starts.

It's like hearing my own voice inside my own head.

So picture this: it's the 1940s.

You're having a great time.

You're here with your friends, enjoying yourself, and then, all of a sudden, out of the trees, you hear this giant swarm, and you don't know where it's coming from, and then they're everywhere, and they're just fighting people, and argh.

But why would this happen?

Because those beetles are fire chaser beetles or charcoal beetles.

What?

Why would you?

This--I need more information.

Fire beetles?

What even is that?

They seek out burned wood as part of their natural life cycle.

And even though they swarmed Berkeley Stadium in the '40s, they're still around today, biting people fighting wildfires and brush fires.

And as to why they would descend on the stadium, picture it like most places in the 1940s.

It's filled with people smoking.

Oh, right, like Humphrey Bogart.

(as Bogart) Let me tell you, kid, there's beetles here.

They didn't teach me that in health class.

Yeah, kids, don't smoke.

You're going to get attacked by a swarm of beetles.

(Trace) Swarms of these fire chaser beetles descend upon the stadium.

They're chasing the firesticks.

Okay, wait, do they, like, lay their eggs in fire like dragons or something?

(Trace) I mean, kind of.

They're called fire bugs or fire chasers because they literally got to lay their eggs next to burning embers.

The fire has wiped out all the competition in an area.

So like a YouTube comments section, the beetles are there first, and their larvae can eat the wood before any other competition gets there.

That is so metal.

Yeah, and when I say swarm, I mean it.

After a forest fire in Germany, an area of three football fields was estimated to contain at least 300,000 larvae.

What?

That's so extreme.

They're first described by entomologists after brush fires and on oil fires, but are also seen in other hot places like walking on pipes that are too hot to touch, in sugar factories, and on logs that are smoldering after campfires.

They get so hot from their escapades that their little, teeny bodies, if they land on human skin, can cause burns.

What?

That's like super extreme.

(Trace) It's an incredible story, and it really got us intrigued.

One, how did they know that all these people were here smoking?

Could they sense it?

And two, could they sense the heat that was coming from those cigarettes, or was it just the smoke?

It might be that they could do both.

So I popped across the bay into San Francisco to find out.

So we're here at the California Academy Of Sciences.

They're going to show us some fire chaser beetles that they have in their specimen archives.

But on my way to meet up with our expert, I, too, Joe, found my way to Africa.

Oh, this is going to be great.

Ooh, okay, Mr.

Cool.

The animals were really easy to take pictures with.

Very still.

It was the--you know, they'd done this before.

Zebras, Joe.

You're not the only one who got to see wildlife.

New kill.

That's wild.

What are you doing up there, kitty cat?

Joe going all the way to Tanzania.

You didn't get this close, Joe.

Wow.

So pretty.

I think I caught this one in "Animal Crossing."

Whoa.

Hi.

Very funny.

Probably smelled better, too.

Whatever.

Eventually, I met up with Christopher Grinter, the collection manager of entomology.

So how many species are down here?

This is huge.

Well, we have hundreds of thousands of species in the collections, with over 15 million insects from all over the world.

That is wild.

These are cool.

I need one of these for my house.

Where are our beetles?

(Christopher) We've got them right here.

(Trace) Whoa.

This is so cool.

Look at these little guys.

(Christopher) There are a variety of different colors.

Some are black, some have spots, some are iridescent green.

They are so small.

I guess I didn't expect something so powerful to be so tiny.

How far away can they sense fire?

Well, actually that was the question that I asked the entomologist because we had him in the hot seat.

Hot seat.

I get it.

Tell me everything.

What--how--how does-- how do these beetles do their thing?

(Christopher) Well, they have an amazing ability to sense fires from a huge distance away.

And they do that with several sensory structures.

(Trace) The beetles can sense smoke in the air with their antennae, and they have tiny sensors on the sides of their bodies under the wings that let them sense infrared radiation from heat.

And these are incredible, they're basically little fluid-covered hairs in a pocket.

The fluid expands and contracts with the heat, and they sense that and follow the sensation.

It's not too dissimilar to how we have fluid-covered hairs in our ears telling us which way is up, but theirs is way cooler or hotter.

So as they fly, their sensory pits-- they kind of face forward so that they're able to triangulate the smoke in the fire and the distance and make a beetle line for it.

But it's a balancing act.

They want to get there soon enough to beat the competition, but not so soon that they waste energy flying around and waiting for the fire to die down.

They want to land on charred wood, not wood that's on fire.

And that is a life-or-death decision.

If they do it right, they breed, and if they do it wrong, they get cooked.

Just like with the dung beetles, these extreme senses are all about resources, passing on genes and breeding.

Yeah, so as soon as those eggs are laid on or under the bark, the little larva will emerge from the egg and burrow into the wood, and they'll spend the next year feeding on the inside of the tree.

So they get, like, a little buffet?

Exactly.

Wow, that's nice, very romantic.

Kind of a little smoldering wood, you know, a little wine.

Yeah, they'll-- they'll mature slowly throughout the year, and in the spring or summer of the next year, they'll emerge and be ready to look for the next forest fire.

How these beetles detect fire from far away is still being studied by scientists working on biomimicry.

These are people who base technological inventions on things invented by nature.

If the studies are right, these beetles beat every human technological IR detector on the market in terms of sensitivity.

They have been spotted in fires a hundred kilometers from their homes.

Wait, that's like 62 miles.

For something that small?

Yes, thank you.

It's like me standing in England and sensing a fire across the English Channel in Northern France.

(posh accent) Oh, dear me, there's a fire in Normandy.

I should go there, lay some eggs in it.

We're talking radio telescope- level sensitivity.

This detection is at the limit of what is physically possible.

Though I should say entomologists are still debating the exact distances and how they do it.

More research is needed, as I like to say.

But I have one last point.

Dung and fire have a lot in common because neither are super pleasant, but both are an important part of the ecosystem, and both are examples of, where there's a resource to be exploited, be it energy or nutrients or water or shelter for your babies, or, you know, whatever that is, there's usually something that's evolved to take advantage of that resource, no matter how rare it is.

And that's especially true where there's competition, right?

I mean, these extreme senses-- they evolved and let these species do what they do better than any of their competitors out there, right?

I mean, without dung and without fire, they couldn't do what they do in their little beetle lives.

(Trace) You could say without those resources, they would have a hard day's night.

Oh, that was a Beatle joke.

You get it?

'Cause the Beatle, with an A, but instead of the double E. They're working overtime.

♪ It's been an arduous twilight ♪ ♪ and I've been toiling like a beetle ♪ (Joe) ♪ Onerous nocturnal period ♪ (Joe and Trace) ♪ What the heck with the dung ♪ ♪ And that big inferno, it makes me feel all right ♪♪ (Joe) I think we got a future in "Liver poo."

[both laughing]