If there's one insect that shows how clever these hardy survivors can be, it's the butterfly's nocturnal cousin, moths.

When I was younger I thought butterflies were really cool, like, I thought, wow, like these small tail butterflies, they're big, and they're gorgeous, flashy.

Now, so now I study moths more, and I've actually come to find moths quite cute.

[slow dramatic music] I've come to really like them a lot, just because they're kind of, I don't know if adorable is the right word, but they're really, they're really wonderful.

[laughs] Something that a lot of people don't know about moths is that they're important pollinators.

We know that there's lots of plants with flowers that bloom only during the night time.

And the major pollinator for most of those flowers is moths.

They may be the forgotten pollinators, but when it comes to adaptation, moths are masters of survival.

For 240 million years, they ruled the night skies.

Then a new predator took to the wing.

[slow dramatic music] Bats.

[bat screeching] This deadly aerial threat triggered an evolutionary arms race, and an explosion in moth defenses.

Bats use echolocation, they scream out into the night and listen for the returning echoes, which shows them where big things are, like trees and cliffs, but also tiny insects that they hunt.

So we think that when bats came on the planet, moths have had to undergo so many different kinds of evolutionary changes to be able to survive against their predators.

The appearance of bats pushed moths to evolve a whole arsenal of defense tactics.

Hairy bodies to absorb sound, long tails to distract them, and the ability to hear and produce ultrasound.

This ability allows them to defend themselves in different kinds of ways.

When moths hear bats coming, they can spiral, loop, and dive to get away.

[bat screech] But many do more than just use their motor behaviors to get away.

They answer with their own ultrasonic reply.

[moth chirping] They can communicate and tell the bats that they're toxic, and chemically defended.

[moth chirping] [bat screeching] Others have the ability to jam the sonar.

In other words, they're able to create a sound that's so loud that the bat can't actually find the moth in the night sky.

[bat screeching] We don't know anything about this process, because everything is happening at night in this dark sky, but we have, now, the equipment to try to unravel this whole system.

[slow upbeat music] Sumaco, Ecuador, is a lowland mountain in the amazonian rainforest in the Andes, and we're going there because there's a really high diversity of moths.

So we think that moths have been on the planet for more than 300 million years.

What's interesting is that bats have only been on the planet for we think about 60 million years.

So within the last 60 million years, these moths have had to evolve to survive, and it's allowed this incredible diversification of moths.

[slow upbeat music] Most of these moths, we haven't seen before.

A lot of hawk moths, lot of atavarius, xylophanes.

A lot of tiger moths too.

The primary question we're driving at is what drives diversity of species on the planet?

And bats are the second most diverse group of mammals.

Moths and butterflies are one of the most diverse groups of insects.

Understanding their interactions, their battles in the night sky, is unlocking many of the drivers of this diversity.

This is a beautiful moth.

Yeah, both of these guys should reflex bleed.

Smells bad, did you smell that?

Yeah.

Oh yeah, very strong smell.

We are looking for particular moths.

Here's one that definitely makes sound, which we know about, this bertholdia.

Oh yeah.

Very loud moth.

The ones that we're interested in are the ones that we know produce ultrasound.

We're also trying to understand other species that might be producing sounds.

A lot of the moths have never been tested, so our goal is to understand what kinds of species are doing it, how they're doing it.

Yeah, look at this.

It's already damaged by a bat.

It's amazing, look how the windows on the wings, they're clear.

You can see through them.

Beautiful.

Being in Ecuador is amazing.

This makes me super happy.

I just love seeing this extraordinary diversity, and knowing that there are places on the planet which still harbor so many different kinds of insects.

[slow upbeat music] Okay, we're doing melese.

Okay.

Rolling.

Part of what we do is play back recorded bat echolocation attack sequences to moths.

And we try to see if the moths respond.

[moth clicking] There it is.

[moth clicking] That looks great, and it's making great sound.

[moth clicking] That was 12, right?

That was number 12?

File 40-- Sorry, sorry, moth number 12.

Yeah, correct.

Got it, okay.

One of the things that we're trying to do is to discover how they actually produce the sounds, because we don't actually know that very well.

[moth clicking] So through microscopes, we can look for the particular structures.

She's using her chest, her thorax.

Well, kind of the back segment, actually.

One way to imagine it is to think of like pushing in the side of a pop can that pops in and then sort of passively pops back out.

And that's the way this works, too.

It requires muscles to pull in, and then it passively pops back out.

We've discovered that some species will produce sounds by rubbing their genitals together, and this produces ultrasound.

[moth clicking] And they shoot that sound at the bats while they're flying.

[moth clicking] Others will rub different parts of their bodies, they have clicking devices that produce sounds.

All these are important in terms of talking to the bats in the night sky.

I think of them as tiny little monsters because of their uniqueness.

There's so much diversity, and you see incredible features doing some function that's helping that animal survive.

And that's just the anti bat side.

They have really long tongues, and they're learning an entire landscape of different flowers to nectar from, they're incredibly important pollinators, and they underpin all ecosystems on land.

And that's why their ongoing declines are so critical to understand.

Because if we lose insects, we lose everything.