Aug 19, 2010

Glad Somebody Likes Bugs...

Evolutionary biologist Jerry Coyne got all soft inside when he thought about how the botfly larva in his scalp was eating his tissue and turning it into a new organism. It was of him, like a child. His friend Sarah Rogerson was a little less charmed, and they both were surprised by the creature that ultimately emerged from his head.

And Tom Eisner, professor of chemical ecology, loved bugs from earliest childhood, kept them in his room to keep him company when his family found themselves living in South America, bug paradise. He knew them well enough to classify them by how they smelled. These days, as he told Robert at the 92nd St Y, his subjects live for sometimes years, well-cared for in his lab, partners in his work decoding chemical signals to reach across the communication divide, trying to shorten the distance between coexisting organisms.

Read more:

Jerry Coyne, Why Evolution Is True

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JAD: Hello, I'm Jad Abumrad. 

ROBERT: I'm Robert Krulwich. 

JAD: This is Radiolab.

ROBERT: And we're talking about how scientists think about the world...

JAD: And appreciate! 

ROBERT: Yeah, except appreciation—this is something that scientists do differently from the rest of us. And I think this next story is an active appreciation so different from the rest of us that it makes me want to...

JAD: Barf?


JAD: Bring it.

ROBERT: Once upon a time in a rainforest in Costa Rica in Central America. There was a little botfly. 

JAD: What's a botfly? 

ROBERT: Botflies are hairy flies that live in moist, tropical areas on Earth. 

JAD: So they're not like New York City flies. 

ROBERT: No, no, no. What a botfly does is when a botfly is pregnant, and our botfly was a pregnant, female botfly. She has her baby. Flies up into the air, carrying her baby. She sees a nice hairy mosquito. Grabs—actually grabs onto the mosquito..

JAD: Mid flight?

ROBERT: Oh yeah. And drops her baby onto the mosquito. 

JAD: Why?

ROBERT: The mosquito—well, because the mosquito's gonna do something very important for the baby. But the mosquito, of course, is a mosquito. So it's looking to bite somebody.

JAD: Right.

ROBERT: When the mosquito lands on a nice, warm, palpitating mammal, so she can have some blood. The botfly baby is programmed to fall off into the mosquito bite and make a little home. 

JAD: Wow, that's impressive.

ROBERT: Completely. Yeah. 

JAD: The mosquito probably has no idea of any of this. 

ROBERT: No idea at all. You got—you got all that?.

JAD: Got it. 

ROBERT: Okay, so now I want to introduce you to a particular palpitating mammal who happened to be in Costa Rica on our very day. 

JERRY COYNE: I guess I was about 24. It was 1973. 

ROBERT: His name is Jerry Coyne. 

JERRY COYNE: 37 years, I guess. 35 years. But I remember it like it was yesterday. This isn't an experience that you forget easily. So...

ROBERT: You were working at Harvard as a grad student at the time?

JERRY COYNE: Yeah, I was. I was doing a laboratory experiment on flies, ironically. 

ROBERT: [laughs]

JERRY COYNE: And there was a program for Harvard graduate students to go to the tropics for two months during the summer so they could get some experience in the field and learn something about the diversity of tropical nature.

ROBERT: So now we've got Jerry Coyne in Costa Rica walking through a forest.

JAD: Doing some research or something?

ROBERT: Doing some research. And through the air you hear the distant sound of a mosquito getting closer and closer and closer to the—[buzzing sound] bites Jerry right on the head.

JERRY COYNE: Not too far from the crown. And—And I scratched it, but you know, it didn't go away. When it got to be about the size of a pea, I consulted one of my fellow students.

ROBERT: This friend of his, happened to be an entomologist. She climbed up onto a bunk bed. 

JERRY COYNE: And she looked in my head, pulled the hairs back, and she said, "oh my God, there's something moving in there." That's when I freaked out completely. I started running around the field station going, "oh my God. Oh my God." I'm just physically running in circles. 

ROBERT: In his mosquito bite, there was a little hose or something protruding... 

JERRY COYNE: Through the top of the mosquito bite, and it was sort of wiggling around.

ROBERT: A breathing tube. Like a little straw. 

JERRY COYNE: I was really completely freaked out. I mean, I had a—a worm in my body. Nobody knew how to extract it. 

ROBERT: Why couldn't you just grab onto the—to the periscope part and pull?

JERRY COYNE: Because, like all marvels of evolution, the—the botfly maggot has devices to keep you from pulling it out because it makes its living in your body. So it has a pair of hooks on—at the anal end, the other end, that are dug into your flesh, so if you try to pull the thing out, it just digs in and you'll break it in two. That is the thing you wanna avoid because it can cause a serious infection. 

JAD: Oh! No, you don't wanna do that. 

ROBERT: No, you don't. But what you could do, however, is you could try what they call the meat cure.

JERRY COYNE: Put a slab of meat over the wound, strap it to you. I would have to have strapped, for example, a steak to my head, which is not very practical. 

ROBERT: [laughs]

JERRY COYNE: And then the worm thinks that—you know, the worm's breathing tube, which is the through the mosquito bite, gets cut off and it's deprived of air. So it thinks that the steak is part of your flesh and it burrows up through the steak. And when it comes out almost all the way, you can just remove the steak with a worm in it. 

ROBERT: What a clever idea. 

JERRY COYNE: Yeah. The idea of toiling in the tropical heat every day, with a T-bone strapped to my head was not something that I wanted to do... 

ROBERT: [laughs] 

ROBERT: Meantime, it's—it's causing problems, this thing.

JERRY COYNE: It was a terrible itch. And from time to time it would like move or twitch and you'd feel this sort of sharp pain in your skull. Or you could feel it grinding up against there. And when I went swimming or took a shower, it would get sort of freaked out because its air hole would be cut off and then it would really go nuts, you know, make a lot of pain. So I tried to avoid getting my head underwater. Meanwhile, the lump was getting bigger and bigger until it sort of got noticeable.

JAD: Wait, how does it—what is it eating in order to get bigger and bigger? 

ROBERT: Well, it's uh.. Um, yes, um... 

JERRY COYNE: It's eating my muscles and tissue and my scalp. 

ROBERT: It's eating your flesh then? 

JERRY COYNE: Yeah, it is. 

JAD: Ugh.

JERRY COYNE: It's turning human flesh into fly flesh. 

ROBERT: This fly... 

JAD: Eh...

ROBERT:'s eating Jerry. So it's more and more—well it is Jerry. 

JERRY COYNE: It is, and that's the part that made me like it.

ROBERT: So Jerry, and the part of Jerry that is now the botfly leave Costa Rica. And it's time to head back to Cambridge, Massachusetts at Harvard University where Jerry's the grad student. And, you know, he has to check things out. 

JERRY COYNE: So I went to the health clinic and, you know, in about 10 minutes there were 20 doctors around me. 

ROBERT: [laughs]

JERRY COYNE: Nobody had ever seen anything like this at Harvard. They were all curious and poking and prodding and looking at it, and ooh-ing and ahh-ing, but of course none of 'em knew what to do about it. And I just decided, screw it. You know, I'm gonna—I'm gonna let it come out, make the best of it. And, you know, enjoy it as much as I could and—and marvel at it. I mean, when you really think about it, it is amazing that an animal can take human flesh and turn it, using its own genes, into a fly. I mean, and you have to marvel... 

ROBERT: But this is so weird of you actually. I mean..

JERRY COYNE: People think this—this behavior might seem weird to the layperson. But to biologists, it's sort of absolutely normal to, you know, be very curious about something. You know, I make my living on flies. I work with fruit flies. I'm a geneticist and—and here was the fly making it's living on me. 


JERRY COYNE: You know, I was getting more and more curious. I wanted to see what it looked like when it came out. I didn't want to kill it. 

ROBERT: What about girls? I mean, assuming you're dating, so like... 


ROBERT: ...wasn't just like a total turn off, to say, "Hi, this is me and my maggot"?

JERRY COYNE: Well, I was, you know, I was dating a nurse at the time. And this is—this is the good thing about it. The nurse was actually quite fascinated with this. 

SARAH ROGERSON: Uh, I thought it was disgusting. [laughs] 

ROBERT: Sarah Rogerson was Jerry's friend. She inspected the fly. 

ROBERT: Did you give it a name?


ROBERT: [laughs] 

SARAH ROGERSON: No. Jerry may have felt that way about it, but, no I didn't. This was more of a scientific experience. 

ROBERT: Is this something you were—was okay with you? 

SARAH ROGERSON: Well, I don't remember being informed that there were any other options. I thought... 

ROBERT: [laughs]

SARAH ROGERSON: I thought this is just what had to happen. 

ROBERT: So a couple of weeks pass and the botfly is just getting...

JERRY COYNE: Bigger and bigger and bigger. 

ROBERT: It goes from jelly bean size to something like...

JERRY COYNE: The size of an egg.

JAD: An egg? 

SARAH ROGERSON: Yeah, it was pretty big. 

ROBERT: Like a quail egg. 

JAD: Whoa. 

ROBERT: He's covering it now with a baseball cap, which is maybe one reason why they decided to go to Fenway Park, one particular evening. 

SARAH ROGERSON: That is correct.

JERRY COYNE: Yeah, there's a Red Sox—Yankees game. I wasn't gonna miss that. And, every once in a while I would rub my head, I mean, throughout this whole gestation of this thing, just to check on it. And during the game, when I rub my head, I felt something coming out of the lump. 

SARAH ROGERSON: Jerry kept saying, "oh my gosh, oh my gosh, it's coming out. I can feel it." 

ROBERT: So was this a little distracting? 

SARAH ROGERSON: Uh, yeah. A foul ball came up where we were sitting and it hit in one of those wooden seats at Fenway and we narrowly escaped getting hit. Because we really weren't paying much attention to the game at all.

JERRY COYNE: But it took a long time. I mean it was...

ROBERT: So it started at the game and then it went on? 

JERRY COYNE: It started at the game and then continued on until the evening. 

SARAH ROGERSON: We went back to Jerry's apartment. 


SARAH ROGERSON: And he kept reaching up and checking to feel the lump. We were just hanging out and.. 

JERRY COYNE: It's a little bit more risqué than that! 


JERRY COYNE: And I said... 

SARAH ROGERSON: He reached up and said, "It's gone!" 

JERRY COYNE: "It's out!" 

SARAH ROGERSON: "It's out!" 

JERRY COYNE: We gotta find it. I turned on the light, and there it was on the pillow and it was horrifying. 

ROBERT: What did it look like? Is it a wiggly little wormy thing? 

SARAH ROGERSON: It's sort of bulbous on one end and then it tapers down to a little tail. It's white.

JERRY COYNE: Big fat white grub worm.

SARAH ROGERSON: An inch and a half long.


SARAH ROGERSON: And it has little black teeth. 

JERRY COYNE: Now I thought, "Oh my God, this, that's what was in my head." Had I known that I might have been more freaked out. 

ROBERT: When you are greeting your baby there...


ROBERT: Did you have a feeling of—of pride? Or just a.. 

JERRY COYNE: Well, no. Extreme curiosity. The one thing that was extremely striking to me was that it's—it—it's exit was completely painless.


JERRY COYNE: You know, it's painful when it's in there, but when it comes out it does so very painlessly. And that's another evolutionary phenomenon. Of course, it's the—if the worm was—did it painfully in exiting, then the horse or the monkey or whoever it's infecting would just slap it and kill it. 

ROBERT: So what did you do once you had the baby there on the pillow?

JERRY COYNE: Well, then I decided I was gonna try to rear it into an adult fly. You know. I'm... 

ROBERT: [snorts]

JERRY COYNE: I'm a scientist, right? [laughs]

ROBERT: [laughs] 

JERRY COYNE: That's what you'd do! So I—I had prepared a jar of sterile sand. I took the worm and I dropped it into the sand and put the top on with air holes and hoped that it would pupate. But unfortunately it died. 

ROBERT: Did you get sad?

JERRY COYNE: I was extremely sad. You know, in the temperate zone in Boston, a botfly is not gonna make it. It just can't live. And so it was doomed from the start, but I wanted to see it complete its life cycle and unfortunately it didn't quite make it. So.. I did the best I could with what I knew. You know, I think it's as—it added some richness to my life, it really did. People still get completely horrified when I tell 'em the story, even though to me it's, you know, it's sort of a nice story. [laughs]

JAD: Jerry Coyne works at the University of Chicago and his forthcoming book is called "Why evolution is true." 

ROBERT: And we have time for one more story. A couple years ago I sat down with one of the great bug scientists, insect scientists in the world. His name's Tom Eisner. He teaches up at Cornell and has taught more scientists to love insects than anyone in the world probably. And I guess I wondered if you spent your whole life having feelings and very sophisticated feelings about tiny, almost alien life forms. How does that happen? We spoke at the 92nd Street Y in Manhattan.

ROBERT: Your interest in insects. Can you remember when it began? 

TOM EISNER: According to my parents, when I first stood on my feet.

ROBERT: Really?

TOM EISNER: All I cared about was bugs. Indeed. Beetles, caterpillars, ants, termites, cockroaches. I picked them up. I learned quickly not to put them all in my mouth. [crowd laughs] I kept them in my room. My room was a zoo. 

JAD: You were born in Berlin?

TOM EISNER: Correct.

JAD: From a Jewish family? 

TOM EISNER: Mm-hmm. 

JAD: You were what—about three years old when you left or thereabouts? 

TOM EISNER: Three years old. Went to Spain. 

ROBERT: So you went from the Nazis in Berlin to Spain?

TOM EISNER: Yes. And the Spanish Civil War, fled for France. My parents decided we should really start somewhere else and we went to South America. And that was an entomological paradise. Every living organism has some sort of odor. You can build these up in your memory. And I used to take a whiff of an insect and classify them in my mind's eye according to what they smelled like. Caterpillars and beetles.

ROBERT: [laughs] And do you ever dream of insects? 

TOM EISNER: Yeah. I—I tend to dream that I am an insect. 

ROBERT: What does that mean? That you dream that you are an insect? I mean, you were scurrying and..


ROBERT: Walking upside down on the ceilings or..

TOM EISNER: Indeed, indeed. Even escaping swatting. [crowd laughs] The weirdest situation that I ever got into in a dream was I dreamed that it was an insect and I was telling another insect that I occasionally dreamed that I'm a human. [crowd laughs] 

ROBERT: That's your meta dream. [laughs] 

TOM EISNER: Insects were somehow my great love. I was very much a loner and, if I didn't have a room full of insects, live, I was unhappy. 

OLIVER SACKS: No, I—Tom. I wanted to ask you... 

ROBERT: At this moment, Oliver S Sacks, who was on the stage with us, he asked Tom this question. 

OLIVER SACKS: Whether you feel that insects respond to you. You know, whether—whether you feel them sort of purring and whether they—they know that you are gentle and reliable, and for them?

TOM EISNER: You know, it's—it's a—it's a good question. I don't—I don't presume to read responses on the part of the insects. But the older I get, the more difficult I find it to experiment with 'em. And there were ways that killed them. Bombardier beetles can live for one, two, up to three years in your lab. You become very attached to them. You give them names. And when they die, it's—it's an event. So you must somehow have moments where you feel that things are going on in that tiny little brain. That they have secrets hidden up their sleeves that they might reveal if you found a common language. I find that I can love nature no matter how distant the individual organisms are from me. But I reach out and hope that I can shorten the distance and create some feeling of coexistence.

ROBERT: Tom Eisner's book is called "For the Love of Insects." 

JAD: That's really what it's called?

ROBERT: Yeah. 

JAD: Well, we should go check our website, for more information, and you can always send us an email at 

ROBERT: Radiolab is one word. 

JAD: Yes it is. I'm Jad Abumrad. 

ROBERT: I'm Robert Krulwich. 

JAD: Thanks for listening.


[LISTENER: Message three. 

JERRY COYNE: Hi, this is Jerry Coyne, the botfly man. Radiolab is produced by Amanda Aronczyk, Jad Abumrad. Our staff includes Lulu Miller, Soren Wheeler, Jonathan Mitchell, Ellen Horn, and Jessica Benko. None of whom are afflicted with botflies. Other help. Ike Shu Kenderaza Chi Chan Lynn. Special thanks to Pauline Davies and Kate Edgar.

LISTENER: End of message.] 





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