ML 141211


Interview 13:44 - 23:53 Play 13:44 - More
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Ronald R. Hoy  







Hoy Lab description; Recorded 2 of June, 1999  

Black Field Cricket -- Teleogryllus commodus 23:57 - 32:40 Play 23:57 - More
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mechanical sound


Recorded 2 of June, 1999  

southeastern field cricket -- Gryllus rubens 45:28 - 51:35 Play 45:28 - More
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mechanical sound



Carolina Ground Cricket -- Eunemobius carolinus 1:06:06 - 1:16:00 Play 1:06:06 - More
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mechanical sound



Ormia ochracea 1:19:19 - 1:25:24 Play 1:19:19 - More
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mechanical sound



Interview 1:38:25 - 2:01:38 Play 1:38:25 - More
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Ronald R. Hoy  







Parasitoid tachinid flies and crickets  

NPR/NGS Radio Expeditions
3 Jun 1999

  • United States
    New York
    Tompkins County
  • Ithaca; Cornell University; Seeley G. Mudd Hall
  • 42.44722   -76.47917
  • Stereo
    Sampling Rate
  • 48kHz
    Bit Depth
  • 16-bit
  • Sennheiser MKH 30
  • Sennheiser MKH 40
    Equipment Note
  • Stereo=1; Decoded MS stereo; Sennheiser MKH40 Cardioid Mid Mic and MKH30 Bidirectional Side Mic; Split track; Neumann KMR 81

Show: Fly¿s Ear
Log of DAT #: 2
Date: 6/3/99

ng = not good
ok = okay
g = good
vg = very good

sound begins

3:00 ¿11:00

technical tinkering

cricket sounds begin

RH 13:37
Would you like me to, sort of, come in here and open up some of these barrels for you?

AC 12:44
Well, just tell me about this room. You¿ve got barrels and barrels of crickets in here,

RH 13:55
Yes, well this, actually, I¿ve been working on crickets for a long time and this room is, is heated and humidified to be like a tropical rain forest so the humidity should be running 80 percent or better and we keep the temperature at about, it¿s a little cool today, but we try to keep it around 86 degrees. And we give them 14 hours of daylight and 10 hours of dark. This is probably the largest colony of crickets for scientific use in the world. We maintain something like 9 different species here.

AC 14:36
How many crickets are in this room, do you think?

RH 14:39
Oh, in this, crickets in this room. If we include all the babies and the adolescents and everybody growing up, we probably have, oh, 100,000 crickets, conservatively. Because we have 8 dishes going all the time, and so we get tremendous hatches of crickets babies which we have to cull out. And at any one time, in order to feed the flies, we need to maintain, we need to keep hundreds of adults coming through the pipeline to make sure that we can maintain the flies. Because the fly life cycle is completed in about 3 weeks, but a cricket takes about two and a half to three months, so you can see that if we didn¿t have a lot of crickets on hand, we would quickly, the fly generations would be, we¿d only have enough to maybe maintain two or three fly generations and then we¿d be out of luck.

AC 15:40
Hold on just a second. They¿re not singing as much as they were. Is that because we¿re talking?

RH 15:49
No, I think we actually hear more that you think we are. There are, they¿re not as loud, but what we¿ve got, so we¿ve got Teleogryllus, that¿s one of the Australian species. There goes the German species, there goes the Mediterranean chirper. I think I hear Gryllus rubens, the Florida one. Yes, we have three different species singing right now. You know, one of the problems may be the humidity seems a little low. They¿re very sensitive to conditions and, oops, I¿m sorry (ran into mic)

AC 17:15
These are what, 10 gallon?

RH 17:19
These are 30 gallon, these 30 gallon garbage cans.

AC 17:22
So 30 gallon garbage cans with plastic lids and a little kind of air vent in the lid and the crickets are, live in here?

RH 17:32
Why don¿t I open up a bunch of them, okay? Because once I open them up, they¿re going to be a little bit disturbed and then they won¿t sing for a few minutes. So, oops, that one already has. Let me open up some of these.

AC 17:58
Aren¿t you, aren¿t you worried about taking the lids off that the crickets will jump out?

RH 18:06
I don¿t think they will. They generally fly toward, I¿m not taking the lids completely off, that one I do because I think this one¿s gonna be okay. Okay, so they¿re gonna be quiet for a little bit. There¿s some action in here. (loud chirps) Can you hear that? That¿s a calling song. That ticking in the background is courtship. I don¿t know whether you can pick that up. (ticking and chirping) Shall I move on? Okay. (19:13- dragging sounds) 19:35- Here¿s your best bet for right now. That¿s your best bet right there.

AC 20:02
How many crickets are in here?

RH 20:06
Okay, we have about, well, my guess is that we¿ve got on the order of, oh, between 50, 50,000, 100,000, crickets in here

AC 20:20
Plus you¿ve got all these vats of flies.

RH 20:23
Yeah, well, flies are much harder to rear, so we probably only have about 150, 200 flies right now. But the crickets are much easier to rear, and as you can see, we have 2, 4, 6, 8, 10, 14, ,16¿we have 22 barrels, 22 30-gallon garbage barrels of crickets. And plus in the nursery, we¿ve got 14, we¿ve got 14 nursery containers over there, and each of those containers probably have about 500 babies crickets coming up at any one time. So we have a whole lot of crickets. The reason why we¿re speaking quietly, of course, is that we¿re trying not to disturb them so that they¿ll come back on and start singing for us again. You can just start to hear over there¿ (silence and cricket sounds)

AC 23:15
What¿s this bin here?

RH 23:18
This is a bin that has singing Australian crickets and I¿m gonna put it down for a sec and hope they start singing again because they were singing very well.

AC 23:37
So what¿s in here? What are these, Ron?

RH 23:44
These are, these are Teleogryllus. It¿s an Australian, it¿s an Australian field cricket and they are, we use these also as hosts for flies.

Lots of cricket sounds
g sounds after 27:50

RH 32:59
Yes. This is the Mediterranean field cricket called Gryllus bimaculatus. What you were recording from before was an Australian cricket, Teleogryllus commodus.

More varied cricket sounds

opening and closing sound

sound resumes outside of cricket room

42:52 ¿ 43:10
generator or fan noise

ticking noise begins

high pitched beeps

loud, rapid ticking noise (Gryllus rubens cricket) at:


CT 52:06
What kind of cricket is that, doctor?

RH 52:09
Did you get it? It¿s Gryllus rubens, which is the host for Ormia ochracea in Florida and the host for the fly when we first started the project.

fight recording begins

g at 55:05, 55:45, 56:35, 57:30, 58:40

technical tinkering

g fighting sounds restart

g at 1:00:54, 1:01:40

¿Cricket Wars¿ end

1:06:06 ¿ 1:16:00
Eunemobius carolinus cricket sings intermittently

CT 1:16:40
And what were those crickets I just did?

Those crickets are Eunemobius carolinus and they¿re a colony that was collected in Mississippi and they¿re common throughout the Atlantic states and the Southeast.

CT 1:16:55
And another question for you generally about crickets. Do they always, when a bunch of crickets are together and singing, do they always sing in unison or is it randomized between them?

It depends. There are crickets that pay attention to each other and adjust their, the temporal patterns of their calling songs relative to what other crickets are doing that they can hear, but there¿s no general answer to that. It¿s sort of a mystery that people are studying, the timing of cricket calling.

¿random discussions¿

These are Ormia ochracea, they¿re tachinid flies, parasitoids of crickets.

1:19:18 ¿ 1:21:14
fly sounds

1:21:37 ¿ 1:25:25
single fly (Ormia ochracea)

¿technical tinkering¿

1:27:39 ¿ 1:30:50
intermittent fly sounds

1:31:10 ¿ 1:32:16
intermittent fly sounds

1:33:01 ¿ 1:37:55
ambi of cricket room

AC 1:38:26
This room is kind of a supply closet size room and it¿s got these plywood shelves on one side, on the left side, as you come in the, in the door and there¿s another shelf on the right hand side. The room¿s maybe 12 feet deep, maybe 12 feet deep and kind of normal heighth with these acoustic tiles and a bunch of shelves and trays and trays and trays of crickets.

RH 1:38:56
Garbage cans and garbage cans of crickets. Right. We keep these crickets in 30 gallon garbage cans. You can raise Drosophila in milk bottles, but crickets take up a lot more room.

AC 1:39:17
How come you have the paper towels in the can?

RH 1:39:21
The paper towels serve as a shelters for the crickets. We raise them at very high densities so that within a 30 gallon garbage can we can have as many as 200, 300 crickets and if they were, if we didn¿t have any shelters for them, they would be literally running all over each other and when they molt, if they¿re not all adults, if they molt, then they would eaten by the others, so we do it to keep down cannibalism and we do it to keep down the certain amount of conflict. It provides hiding places.

AC 1:39:57
The can is full, the garbage cans are full about halfway with these crumpled up brown paper towels and the crickets are all down among them, so when you, when you are listening in the can, you hear all this scurrying around and then you hear some singing, and that kind of, kind of crinkling sound you¿re hearing, that¿s actually crickets scurrying.

RH 1:40:24
That¿s right. You¿re hearing the footfalls of the crickets.

AC 1:40:27
And there are maybe 200 crickets in a barrel.

RH 1:40:31
That¿s right. In a typical barrel, and in the barrel that you¿ve got your microphone down in, it would certainly be 200, maybe 300.

AC 1:40:44
I¿m actually not hearing 200 cricket voices, though. I¿m only hearing a few.

RH 1:40:48
Right now, yeah, that¿s true, because crickets only call when there¿s a reason for it, the reasons being related to fighting. So when a couple of males come upon each other, they¿re gonna fight. And if a male comes upon a female, he¿ll start courting. All that, all that crumpled up paper reduces the probability of two crickets colliding and that¿s partly the point.

AC 1:41:17
When you listen in this can, you¿re hearing crickets actually the way the fly hears them.

RH 1:41:24
Yes, pretty much, that¿s right.

AC 1:41:27
Is there something that the crickets are doing that would be more attractive to the flies than something else?

RH 1:41:33
Well, what the, what the crickets are doing, in fact, in the background now I can hear couple of crickets calling. The crickets primarily call in order to attract females of their own species for mating and as I¿m listening, as I¿m listening I can hear three different kinds of calling songs, so this is what the fly would hear, and presumably, she would for whatever reason, she would pick one of these out and home in. Now of course the male cricket singing to get a female cricket is not singing to get a female fly, but that¿s what this, that¿s what this parasitic relationship, this parasite-host relationship has evolved to accomplish. And one that we¿ve been having great fun exploiting to study.

AC 1:42:24
You actually wanted to talk again about how you came upon this idea of doing this.

RH 1:42:29
Yes, right. This relationship between the host, between a cricket and a fly, really piqued my interest when I read a paper by a friend and colleague named Bill Cade at the University of Texas. For his Ph.D. thesis, he was studying cricket songs and he noticed that in playing cricket songs, sometimes he would capture a fly on his speakers instead and the result of this was that he was able to establish that these flies were parasites, parasitoids, on crickets and that the flies found their hosts by using ears, they had evolved, they had evolved ears to hear the crickets. And what the fly gets out of it is that, these are female flies, gravid with larvae, maggots if you will, and when she finds the host, she flies down and deposits a few, two or three, maggots on the host and then flies off and looks for another cricket. This was about the mid 70s, and so now we have this phenomenon of acoustic parasitism. The question is, ¿How, we have the phenomenon, but where are the ears?¿ And this was, so when I read about it, I said, ¿Gosh, that¿s going to be a really interesting project, but life gets busy for us all and it wasn¿t until 1990 that I revisited this and the occasion was when a very talented postdoc from Switzerland named Daniel Robert joined my lab and was looking for a project and I said, ¿How¿d you like to go to Florida?¿ And so Daniel took this up for his project and he was joined there with Dr. Tom Walker who has been studying mill crickets for a good part of his life. And mill crickets are interesting in this regard because they, too, are hosts for parasitic flies. And the problem with mill crickets and what motivated Walker to study the phenomenon is that mill crickets tend to dig very large holes in turf. So in Florida, you can imagine that would be a real problem, especially in golf courses. So Professor Walker¿s research had been funded by the golf association for a long time because mill crickets do a lot of damage and so by introducing parasitic flies, the notion was to reduce the population of mill crickets. So Tom has had a release program in golf courses in central Florida for a long time and presumably, it¿s keeping it down, so the putting greens are, Tom¿s helping keep the putting greens safe. Anyway, what Daniel did was in conjunction with Tom, get a, start up our own colony of flies, and Daniel was able to discover, in very short order, the fly¿s ear, and it¿s up on its thorax, up on the chest of the fly, if you will, and we¿ve been going, we brought the flies back, we bred them at Cornell, as you look back of you, Alex, you can see the results were in our 59th generation of flies from Florida and we¿ve just had fun for these past seven years doing it.

AC 1:45:48
You know, you were saying in your office earlier that the discovery of this relationship and then the discovery of the ear and then the idea of what you could do with that knowledge has been, it¿s just been very rewarding for you, and how is that?

RH 1:46:08
Well, I¿ve been studying insect ears for almost 30 years, at least 27 years. And while it¿s been great fun to discover new ears in new bugs and my colleagues reward me with a, ¿Gee whiz, who would have imagined that?¿ and of course, it¿s been good for my career, I couldn¿t help but feel, especially when I¿d go home sometimes and I¿d tell my parents or tell my mother. She¿d say, ¿Well, tell me what you¿re doing. Teaching, well that¿s good. And you¿re doing research, too?¿ I¿d say, ¿Yes.¿ ¿On what?¿ And I¿d explain about insect ears and she¿d usually say, ¿That¿s nice,¿ but I¿d know what was going on in her mind was ¿Bug ears?¿ Which is in fact what some of my colleagues in molecular biology will say. ¿Gee, Ron, when are you gonna study something else?¿ So¿ (AC: When are you doing to do something useful with your life?) Why didn¿t you become a real doctor? But, when we came upon the fly¿s ear and started the collaboration with Daniel and then brought Ron Miles on in mechanical engineering. When we discovered that the fly had invented a different kind of ear, that was extremely rewarding in the basic science sense. But then Ron and Daniel realized that gosh, you know, it¿s a small ear, and it¿s, for a direction-finding ear, it¿s unique. So maybe, what if we, in engineering, could make an ear like that and put it into something like a hearing aid. That just made my, it did my heart good. I felt so great, because I didn¿t know that I¿d been suppressing this, or internalized my parents¿ and my friends¿ message. Why are you studying bug ears? And when I heard that, my God, this could actually turn out to be worth something and might be worth something out there in the real world, I was just delighted, and it was, so that¿s for me, this has been one of the highlights of my life.

AC 12:48:12
But you didn¿t actually know you felt that way.

RH 1:48:14
No, I didn¿t know. No, of course not, because we tend to rationalize our work and of course I¿m proud of my accomplishments. I feel that we, and it¿s been fun along the way, too. I¿ve met a lot of wonderful students and had some wonderful colleagues, but I didn¿t think that I really needed to justify what I did. So I was surprised when it became clear, that gosh, somebody was, the NIH might, in fact, be interested in realizing the fly¿s ear as a hearing aid, which you¿ll hear about from Ron Miles. I was just, I couldn¿t have been more pleased. It was just a great moment.

AC 1:48:55
You know, you must have this, I mean we¿ve talked about it, that you¿ve had this sensation, or this has occurred to you, repeatedly probably. You meet some people, you¿re at a cocktail party or your neighbors or something and you¿re introduced, oh, you¿re Ron Hoy, you work at Cornell, oh, what do you do. What do you really study? You say, ¿Cricket¿s ears¿ and people say to do, ¿Well, what is interesting about cricket¿s ears?¿ What do you tell them? And you¿re dealing with people who are like me, who are just kind of normal people who don¿t know what¿s interesting about cricket¿s ears and are not scientists.

RH 1:49:33
Sure, and in fact, one of the reasons why I studied insects in the first place was that in studying animals less complex than ourselves, but are still, are still engaged in the act of hearing, we¿ll still learn something about the hearing process. In fact, this is an old strategy. I mean, a lot of what we know about the enzymes that digest our food and the role that vitamins play in our body weren¿t necessarily learned in studies of nutrition directly, but especially the biochemistry and the molecular biology, we learned about it by studying these enzymes in bacteria and so this is sort of a model systems approach. The leading question here is the extent to which we can use simpler organisms to explain how nervous systems generate behavior. That¿s one of the things that interests me. And a cricket has a far simpler nervous system than a bird, a frog, or a human, and yet we all hear 5 kilohertz. You and I can hear the cricket¿s songs. Whether or not we process them in exactly the same way the cricket does isn¿t completely clear, but nonetheless, it serves as a model, as stepping stone.

AC 1:50:15
How many crickets are in this room, do you think?

RH 1:51:17
Oh, probably about 50,000 crickets and about 200 flies.

AC 1:51:28
What¿s that down there? There¿s a cricket down there in a pail of sand.

RH 1:51:34
Oh, yes. I don¿t think it¿s alive, I think it¿s just a¿(Alan comes in and jokes)

AC 1:52:04
What¿s your name?

AW 1:52:05
My name¿s Alan and I was recently hired by Professor Hoy to be a research assistant and to help take care of the flies here in the lab.

AC 1:52:12
Alan what?

AW 1:52:13
Alan Willams.

AC 1:52:15
And you¿re a sophomore at Cornell?

AW 52:16
I¿m going to be a junior this coming year, after the summer.

AC 1:52:21
And you take care of the flies?

AW 1:52:23
Well, I¿m the breakdown, I¿m actually going to be paid and I¿m gonna be getting some credit for working here. As Professor Hoy would tell you, the paid component of my job will be to taking care of flies whereas I¿ll also be getting credit to work with Andrew on his flies and basically looking at different projects throughout the lab.

AC 1:52:44
One of the things that, one of the things Dr. Hoy has just mentioned in passing that struck me as odd was that it¿s much more difficult to raise flies than it is to raise crickets. It¿s easy to raise crickets, it¿s much more difficult to raise flies. Why is that?

AW 1:53:00
Well, I can¿t say that I have much experience with it, seeing as though I¿ve only been here, actually it¿s only my third day being here, but I can tell you just from getting back in the other lab and dissecting flies that it¿s all about scale, it¿s all about size. That¿s a big factor in that the flies are a lot more mobile and a lot more smaller and harder to deal with in that case, but I can¿t say I know much more about it than just that.

AC 1:53:24
When you tell your friends that your summer job is tending a bunch of flies¿

AW 1:53:35
Well, they laugh, but compared to what they¿re doing, I can say that I¿m having a lot more fun and getting a lot more experience than what they¿re doing, so if they laugh, I just ignore it because I know that I¿m doing something good.

AC 1:53:48
What are they doing?

AW 1:53:50
Well, I have one friend who¿s painting a house. I have another friend who¿s working at the Gap. Most of my friends are just hanging out for the summer because they don¿t really see the future, so they just want to hang out and have a good time while they still can., whereas I know that there are more important things right now and that I need to get some experience, put things on my resume, you know, and just have a good time.

AC 1:54:33
Well, you were gonna tell me about that cricket down there. There¿s a cricket, we¿re here in kind of the storage room and I see there¿s a bucket of, I think, sand down there, and there¿s a cricket lying on top of the sand.

RH 1:54:43
Well, you know, I think that¿s just leaving. It¿s a dead cricket and I think that when we were washing the dishes, one of them just kind of slipped out. So that, it¿s just a hoax.

AC 1:54:56
Do you ever lose crickets in here? What happens when the crickets escape?

RH 1:54:59
Well, we have seals around, around the room and this is a room within a room, so the crickets really don¿t escape out into the halls, although people accuse me of having crickets that escape because a lot of people here raise snakes, they raise lizards, and they raise frogs, and to feed them, they need live food. And the most common food to feed animals like this are crickets, but they¿re different species from what we use here, so the real cricket farm around here is in Baton Rouge, Louisiana, Fluker¿s Cricket Farm, and they provide the aquarium industry and the museums, zoos of the world, of the United States with crickets. And so these are the little tan crickets that you can buy at any pet shop for a quarter or a buck a piece depending on the store. So, but they¿re not mine, we don¿t study those kinds of crickets. They¿re a little too common. We like the exotic stuff.

AC 1:55:54
If they ran out of their crickets, would they ever come in here and say, aw, to heck, Ron¿s really not gonna miss a handful of crickets and they¿re really gonna matter to my frog.

RH 1:56:08
I get asked a lot. Look, the crickets didn¿t come in this week. Can I have about 50 or 60 of yours? And yeah, sometimes I give them a few. So, but, and unfortunately, they like mine better because they¿re livelier and they¿re bigger. But I do not provide people with lizard food.

AC 1:56:26
These are serious research crickets.

RH 1:56:29
Right, that¿s right. I have teams of undergraduates who keep this, who devote a good part of their lives, working lives, anyway, to making sure that we have healthy crickets.

AC 1:56:44
And crickets, you are interested in crickets, really, because they¿re the right, I mean, you could be studying frogs or flies or, but the nervous systems of crickets are simple and clear enough and they¿re, maybe they¿re big enough, they¿re the right size. They¿re not too small, they¿re not too big.

RH 1:57:02
Well, the thing about crickets that attracted me was that , yes, they have a simpler nervous system, but they use their songs for the same reasons that frogs chorus or call, birds use, that birds sing, so it¿s basically about territory. Two males call to dispute over a territory or they¿re fighting over a female, fighting over some resource. Crickets do that and the other context is males often call to attract a female and this is true for frogs, it¿s true for some birds, and crickets do that. And I would maintain that it¿s not totally unfamiliar in the mammalian realm, either. So, in terms of model systems, I think that what we learn about crickets and how the nervous system mediates these behaviors will inform, will tell us something about how frogs do it, maybe birds do it, and who knows, maybe Cole Porter had it right, the bees do it, fleas do it, and my crickets are pretty educated, too.

AC 1:58:12
Just about the flies and the crickets. How, how did it seem to you when you first kind of recognized this relationship between the fly and the cricket aesthetically?

RH 1:58:30
Well, as I said, I came upon the relationship by reading about it because Bill Cade had discovered it, but I thought it was just really, really cool that here you¿ve got a fly which has broken the cricket¿s communication code, as it were, that you¿ve got a fly playing the game of cricket. I mean, crickets, male crickets are out there calling to attract females in order to reproduce and here¿s a fly that has essentially broken the code. She is using the cricket¿s song in order to find a male to complete her reproduction and this is an example of co-evolution. It¿s one of the most fascinating aspects of evolutionary biology and here was an opportunity for us to figure out mechanistically how these animals bring this off.

AC 1:59:28
When you go out to talk to people, grade school kids about biology, about your work, you use this example for popular culture that¿s very familiar to all of us when you¿re talking about the flies and the crickets.

RH 1:59:47
You mean Alien, of course, sure. Well, everybody in the world and especially school kids, high school kids love it, but even elementary school kids seem to recognize it even though the movie is R the last time I checked. I think that the, well, in fact, what actually happens, the nitty gritty of the fly completing its life cycle is that the female fly deposits a tiny little maggot that you can hardly see, it¿s half a millimeter long, and then it grows up to be a bigger and a bigger maggot within the cricket so that when it pulls out of the cricket, it¿s almost a half an inch long, and when they chew their way out of a cricket, you can¿t help but think of the image of Alien and so, it¿s a compelling one. I use it all the time in, I have pictures of it and I show it up on slides. Kids love it, so it¿s¿

AC 2:00:49
Are you ever horrified by what you see?

RH 2:00:53
Well, not really. I¿m an entomologist and, you know, there¿s a wonderful diversity in life. I would maintain that a lot of filmmakers study entomology books in order to get models. Now, true it may be for horror movies, but, you know, just a quick run-through of some of the action features and the monsters and what they call aliens. They¿re not much more than real big colorful bugs in many ways. So does it horrify me? No, you know, being a biologist, we sort of know that there are an awful lot of different takes on the world and I suppose if I was anthropomorphic about it, it would be bothersome, but no, I just love the diversity of life.

AC 2:02:15
end of sounds

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