How An Elegant Moth Stays Aloft

Nov 4, 2011
Originally published on November 4, 2011 1:37 pm

Transcript

IRA FLATOW, host: Joining us now is Flora Lichtman, one of the, with...

(SOUNDBITE OF LAUGHTER)

FLATOW: How are you, Flora?

FLORA LICHTMAN: I'm pretty good. How are you?

FLATOW: I'm getting the mouth to work better. What do we got this week?

LICHTMAN: This week is pretty neat. We have footage, really beautiful, high-speed footage of a moth. And believe me, this is a moth like you have never seen it before. When I think of moths, I think of them bumping into lights and bumping into my screen door - clumsy.

FLATOW: Right, right.

LICHTMAN: Clumsy flyers.

FLATOW: Fly in circles, going around places. Yeah.

LICHTMAN: This is the most graceful creature. And, in fact, it's a hawk moth, and it's also called a hummingbird moth. And that's because it feeds in a very similar way to a hummingbird. So these moths approach a flower, and they unroll this long proboscis, which is basically like a tube. It's a straw. It's a straw...

FLATOW: It looks like a hummingbird's - straw, yeah - go ahead.

LICHTMAN: They have a beak, but anyway...

FLATOW: Yeah. Yeah. A long straw.

LICHTMAN: Then they use a tongue, apparently, which is weird. But - so these moths use a proboscis. And Ty Hedrick, who's the researcher who studies them, say they approach and they have to kind of hover in front of the flower. And this is - he describes the problem they have.

(SOUNDBITE OF VIDEO)

TY HEDRICK: Just holding position in front of a flower and trying to drink out of a straw, now that's as long as your own body, means you have to be able to hold position extraordinarily precisely. It's really treading water in the air with its wings.

LICHTMAN: And that's exactly what it looks like...

FLATOW: Right.

LICHTMAN: ...when you see them in this video. And so the question that Hedrick wanted to understand is: How do they do that? I mean, they're these really lightweight creatures. There's wind blowing. There are other moths around. How do they stay so still? And what he did to figure this out was, basically, to try to knock them down, to destabilize them. And this where the video gets crazy.

(SOUNDBITE OF LAUGHTER)

FLATOW: Unlike your other videos, this is like...

LICHTMAN: No. This one really takes the cake. I couldn't believe it when I saw this footage. So basically, they took a cannonball shooter from a pirate, like, toy ship and modified it in a 3D printer. So it didn't shoot - it used to shoot darts, and now it shoots these tiny, little modeling clay cannonballs. And they shoot the moths as they lure them in to take a drink of this fake flower. They nail them with these cannonballs. It's a little - it's painful to watch.

FLATOW: But no moth was hurt in the production of this...

LICHTMAN: So they say. I mean, I gave Hedrick a hard time about this.

FLATOW: You can watch the video.

(SOUNDBITE OF LAUGHTER)

LICHTMAN: And he was like, they have an exoskeleton. They keep going back. They're fine. Don't worry.

FLATOW: And it's...

LICHTMAN: But you can decide for yourself.

FLATOW: Yeah. You look at the video, and you see these little - these moths, which are beautiful. They look just like hummingbirds, and you'd think they are hummingbirds.

LICHTMAN: Yeah.

FLATOW: And they're able to maneuver with this giant straw coming out of their nose, it looks like...

LICHTMAN: Yeah.

FLATOW: ...and stay in position while they're flapping their wings in slow motion. It's very pretty.

LICHTMAN: It's very pretty. He said, actually, if you want to imagine the problem that they have, think about taking a straw that's your body length, and then trying to take a drink out of a 7-Eleven cup. You are standing on the ground, and that would be tricky. Now imagine if you're treading water or you're flying in the air, it's kind of amazing. So that's what they're studying.

FLATOW: And this - and so they're studying how this - how the moth is able to stabilize itself. And you can see in the slow motion, its body is moving, but the head is abso-- like a ballerina, and it's beautiful.

LICHTMAN: This is the kind of amazing thing that they found, the flapping. The way that these moths fly actually is what keeps them aloft. They don't have to do much thinking, in other words. So they sort of invest in this flapping strategy that makes them way more stable than they would be if they were flapping in a different way, or they had a helicopter or something.

FLATOW: Right. Right.

LICHTMAN: And that's how they, you know, kind of survive the swatting and these other things.

FLATOW: It's our Video Pick of the Week. It's called...

LICHTMAN: It's called "When a Moth" - "How is a Moth like a Hummingbird?"

FLATOW: "How is a Moth like a Hummingbird?"

LICHTMAN: See for yourself.

FLATOW: Yeah. You can see for yourself, when a moth is like a hummingbird. It's our Video Pick of the Week. It's up there in our website at sciencefriday.com. And...

LICHTMAN: Let me sneak in one more thing. Our egg contest...

FLATOW: Oh, yes.

LICHTMAN: If you entered the egg contest, the results are coming next week. Thank you to the hundreds of people who replied. And to the dozens of people who got it right - which was amazing to me. I mean, I had no idea. So...

FLATOW: That was the egg up in the weightlessness of...

LICHTMAN: Egg in space.

FLATOW: Egg in space contest. Thank you, Flora.

LICHTMAN: Thanks, Ira.

FLATOW: It's up there in our Video Pick of the Week. You can go to our website at sciencefriday.com and have a look. Transcript provided by NPR, Copyright NPR.