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Interview 39:40 - 2:02:21 Play 39:40 - More
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Rex Cocroft  

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Treehoppers  

Environmental Recording 1:35:05 - 1:40:34 Play 1:35:05 - More
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General location ambi  

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NPR/NGS Radio Expeditions
13 Sep 1999

    Geography
  • United States
    Virginia
    Loudoun County
    Locality
  • Leesburg
    Latitude/Longitude
  • 39.10917   -77.55778
    Habitats
  • Rural
    Channels
  • Stereo
    Sampling Rate
  • 48kHz
    Bit Depth
  • 16-bit
    Recorders
    Microphones
    Accessories
    Equipment Note
  • Stereo=1; Decoded MS stereo

NPR/NGS RADIO EXPEDITIONS
Show: Bug Communication
Log of DAT #: 1
Date: 1999

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

Absolute Time total time 2.01.57

0.00.00 -0.02.17 messing around with camera and mic set-up.

0.02.17 -0.04.58 Alex explains to someone about how to make accelerometers and set them up.

0.04.58 -0.07.45 engineers talk about pre-amps with RC.

0.07.45 -0.08.20 AC: How does a biologist learn so much about electronics? RC: I took the most useful course I ever took, which was an electronics course at the community college up in Ithaca. I never learned anything that practical up at Cornell.! took a little course and got a little certificate that I'd completed this electronics course and I didn't really learn enough to be able to design my own circuits, but I learned enough to be able to follow one. So that's an extremely useful-that and Spanish were maybe the two most useful courses I've ever taken.

0.08.20 -0.09.11 Camera people talk about things.

0.09.11 -0.1 0.03 AC et al. Talk about coffee, camera stuff, general stuff.

0.10.03 -0.11.47 camera people get the accelerometers set up -lots of feedback, chatting about it.

0.11.47 -0.12.06 false start

0.12.06 -0.13.09 RC: Because these phono cartridges are so sensitive, that I thought it might be worth trying to rig up one for use in the field which is difficult, but by mounting it to this little clip, we can attach it to a branch and have the tip of the stylus touching some other part of the branch and get a pretty good signal but what I want to do now is use one of the ones that Dennis made up this morning that has a nice light cable which'll make positioning easier and then mount it on another little clip here so that we can attach it and then we'll run that down come out of the speaker. AC: So where are those that we had made at NPR RC: Oh, I've got them over here, and then what I was going to do is get a little bit of tape from Ned or somebody, and -this works, I was hearing some great calls just now... AC: we're probably too late, they probably won't call again ...

0.13.08 -0.14.14 RC setting up the accelerometer on a branch. Crickets, birds, far plane.

0.14.10 -0.14.36 Good ambi (cicadas!) with talking-RC: "let me just make sure this is connected and sounds good, and then we can try running it into the speaker ..." great ambi here or cicada -no planes!

0.14.36 -0.15.47 AC: What are you doing?

RC: I'm just trying to get a good contact here between the stylus on the phono cartridge and the part of the plant, mind you this is not in the manufacturers instructions for these phone cartridges

AC: What you're doing is,

RC: This is an awkward system, I think we could probably improve on it with another 15 minutes in the NPR shop,

AC: So you're clipping this little phono cartridge on the woody part of the stem and trying to rest the needle on one of the green sub-stems that comes off of it?

RC: yeah. The technique as I said, especially developed for Radio Expeditions -don't tell anyone I did this. All right, let's see how this sounds ...

0.15.47 -0.16.49
AC and RC chat about the sounds they're getting from their accelerometer. Then how they're recording it, and setting in up with a speaker.

0.16.49 -0.17.30 a lot of mic bumping here at the beginning (but good info) RC: There's a guy I know in Arizona who studied vibrational sounds of velvet ants, long before anybody else had really -most people had begun being aware of this kind of communication, And he's great at working out gadgets using every day stuff, so what he's got is he put an accelerometer on a Mesquite tree outside his house and hooked that up to a baby monitor, and then inside his house he's got the baby monitor speaker so he can just lie there and turn it on and see what's going on in the tree! [laugh]

0.17.30 -0.18.04 RC: That's why I was admiring those radio controlled, you know those little broad-transmitter, those little things you've got because that could potentially be pretty useful. Now there's an ant investigating the microphone here ...

0.18.04 -0.18.28 Camera stuff.

0.18.28 -0.19.44
RC chatting with AC and camera people about hearing the accelerometers and their set-up.

0.19.44 -0.21.01 Sounds of the treehoppers -with a lot of induction hum! Being played on speaker into mic (it sounds like) with cicadas in background. Rex talks about how to set it up with headphones.

0.21.01 -0.22.39 RC: Okay, mostly you're hearing wind right now, and if you want to adjust the gain it's right here, but you'll notice, once the wind stops,

AC: Wow!

RC: Yeah, it's a tremendous amount of noise all through the whole plant.
(good ambi of cicadas)

AC: There's this tremendous amount of clatter that I'm hearing in the wind and it must be the -these leaves kind of rustling, but ... I try to think of something to compare it to, but I can't think of anything this actually sounds like -it's just an enormous clattering racket.. And I don't hear, I don't hear the treehoppers calling at all.

RC: That's what I've noticed too, that during the gusts of wind they completely quit calling. Because you would be able to hear them over that wind - they use different frequencies. So I don't think it's that we're just not hearing them, that they're masked by the wind, I think it's that they're not calling.
[bug sounds barely audible]

0.22.39 -0.23.09 AC: There they are ... [barely audible bug sounds] RC: A few calls right between the window-AC: The wind stopped and just for a moment the wind stopped, and right away there were 2 calls. [ambi, very light bug sounds]

0.23.09 -0.23.59 Stylus becomes displaced. Rex turns it off to move it a bit. Talks with Alex about the difference between accelerometer and the stylus thingy.

0.23.59 -0.24.47 camera schtuff. RC re-does something for the camera.

0.24.47 -0.25.25
AC: God! The ants are attacking the phono-cartridge and there's a lot of crackling up there from them

RC: yup

AC: and there's this great humming going on... There was great humming going on, but then this gentle little breeze which you could probably just barely hear on the microphone came up, and in these headphones connected to the phono cartridge, it just sounded like a gale was blowing through a saloon and knocking over all the pitchers of beer and the chairs and everything else in the way - it just sounded horrendous.

0.25.25 -0.26.20
Becomes disconnected again, try hooking up the accelerometers .. AC and RC talk about how to do it.

0.26.20 -0.26.40 Messing around with camera etc, trying to get a good shot,

0.26.40-0.29.48
RC: So I'm sticking the accelerometer onto the stem, [something] and then I'm going to clip the cable on down here to support it, and you're ready to roll..

AC: I don't hear anything [mic bumping] They try to work out problem -(they aren't getting signal)

0.29.48 -0.38.14
RC and everybody getting into position. Plane flys over. Still trying to get signal from bugs. More engineering talk. Banter about Radio Shack. move from line to mic input.

0.38.14 -0.39.40 AC listens to the first bug sounds with the new set-up AC: Oh my God, its just this, gail blowing through the saloon again ..But they're calling a little bit behind it. [ambi, very faint bug sounds in background]

0.39.40 -0.40.35
AC: So one call goes rrrrrrr and then there's this kind of lower throatier kind of rrrr-rrrr-rrrr

RC: those are both produced by males and then the ta-ta-ta-ta-rrrrrr is the advertisement call, so that's the one that males go around when they're mate-searching, and if the females accept, they should respond to that with another call, but the other little brr-brr sound is from males that are, that either two males meet each other on the branch, they'll give those signals, or if the male's sitting in a little group and another male comes up, they'll give those signals and so it's by context alone, it seems to be a kind of male-male aggressive signal, but how it works and why other males would pay attention to it, I don't know. It could jam the female's response signal, or it could simply advertise that there are other males around.

0.40.35 -0.41.13 good long ambi track without planes! Birds crickets.

0.41.13 -0.42.35
AC: Now we're sitting here beside the tree, which is really a, more shrub than tree, you wouldn't think of it as a tree, but it's a young black locust, and Rex is listening on the headset that's plugged into the accelerometers that are on the stem ... And the wind has stopped blowing, and there's a smile on Rex's face, so

RC: I'm hearing lots of calling probably from males from that little group there, they're about 3 or 4 inches away from the, where we're plugged in. AC: That's 3 or 4 inches up this, the real woody part of this stem, and if! were just to guess looking at that, I wouldn't even think that a sound vibration would carry through that.

RC: On a really thick trunk they don't carry that far, but actually a woody stem is better at transmitting these sounds than a really fleshy succulent stem. So that's actually a pretty good little vibration channel there, it's about as thick around as a pencil and it's a dense woody stem, so it transmits these sounds really well.

0.42.35 -0.43.14 [a few good seconds of ambi]
[mic bumping throughout] RC: We can try also a few other --I heard some good stuff, nothing super close, but we can also try other areas like, I don't see a lot of male calling activity down here, down in the shade and they're less likely to be really active there in a cooler shady spot, but we can try listening down near there. We can also try listening down near those trees like out in that are, although they're a little more exposed and windy

0.43.14-0.44.16 messing around, setting up mics, camera, etc.

0.44.16 -0.45.29 RC: ... would be goldenrod, because that's supports a whole insect community. So that's another sound recording task of lower priority than getting good recordings of these

AC: yeah. Well I don't want to clip this stem now, because once you clip it, then we'd have to find another colony, and this is sort of your best local group, right? RC: Yeah, best right around here -I haven't looked too much farther, I've looked a little bit, but it could take a little while to find another good group. AC: so in terms of -if we want to get the best recordings we can, you're saying we should actually clip the stem to get the best recordings we can -but maybe we should just try getting stuff here first RC: Yeah, we can just try getting stuff in the field and that'll be good because we'll get wind, and maybe get that effect of you've got some wind and then it stops and the bugs start calling, that's kind of neat. Sort of interesting phenomenon, it's fairly robust.

0.45.29 -0.45.51 CJ: Is this the best time of the day to be -RC: anytime that it's warm anytime after, say, 10 o'clock, if it stays warm in the evening, they'll call into the evening, but sort of 10 to 4 is a good time.

0.45.51 -
AC and RC talk about where they are positioning the accelerometers. And how they're going to record him looking for the right branch ...

0.47.35 -0.48.30 RC: ... wind in the trees. AC: You've never heard it like this before? RC: No, not in stereo! It, [pause] it's weird because it's hard to translate our having 2 ears in a three-dimensional medium into what it would be like to hear something in stereo on a plant stem, but I all of a sudden feel like I'm surrounded by waving leaves hitting against each other, it's neat! [barely audible track of leaves] Ambi

0.48.30 -0.49.57 ambi, airplane. AC talks about pop on tape RC and AC laugh at party analogy to amplified leaves. Good ambi, with light bug sounds.

0.49.57 -0.51.20
RC: The insects have now turned into mollusks and they're just holding limpit-like onto the branch. [pause] Now it's calling, a little break in the wind. RC talks about the wind in this vein. How to get a good stereo recording.

0.51.20 -0.53.42
RC and AC talk about getting a good stereo signal, bugs talking to each other. Long pause as they listen, couple planes go by.

0.53.42 -0.53.52
RC: You're face is a good insect-o-meter, because every time one calls near by, your face lights up ...

0.53.52 -0.55.17
RC and AC listening to the accelerometers, very faintly recorded on tape, ambi.
Airplanes.

0.55.17 -0.56.12
RC: What I'm hearing is that we're definitely getting a spatial effect, but the one signal is dying out so much by the time it travels this 20 cm down here, 15 cm, that we're not, it's more like you're hearing it almost only in this ear, or only in this ear. AC: I think you should put this on and listen to it and record for a while, but I also think we gotta solve this little clicking problem,

AC and RC talk about engineering so there's no clicking.

0.56.12 -0.56.25 mic bumping.

0.56.25 -0.57.10
RC: Okay, were going to go look for other insects on plants, right now we're in an environment surrounded completely by plants and we're looking for things about 3 millimeters long, so it looks like a tough task, but it's made a lot easier by the fact that these are host specific, so there only on black locust. So that's our first way of narrowing down environment, we'll look just on black locust. And then, because these are mutualistic with ants and they have to be in order for colonies to maintain themselves, your first clue that you're finding insects is often the ants that are running around on the branches, so what we'll do is we'll go out and look along this row of black locusts and look for one that has ants on it, and they'll show us the treehoppers.

AC: okay.

0.57.10 -0.57.47
Walking off into the forest to look for treehoppers. Ambi, footsteps, mic bumping,
crickets.

0.57.47 -0.59.20
RC: So we can also narrow down the search quite a bit by looking on young trees and saplings, because the nutrition is best for the insects at growing places on the plant, so if we look at young growing plants, those are going to be good host plants.

AC: is this a black locust here?

RC: yes, and this is also a good spot to look because it's in an area that gets a lot of light, and the insects like a high-light environment. Okay, so here we are, there's ants running around, and low and behold, there's an aggregation of about 8 treehoppers, when you first look at it almost looks like there're 50 insects there, but it's just because they're covered with ants, there really are, only about, oh here's a few more, maybe 10 treehoppers in this stretch.

AC: And if we put the microphones on the stem, we put the accelerometers on the stem, we would hear those things, they're calling now, you think?

RC: Probably. Okay, and up at the very top of this tree about 9 or 10 feet up you can see a couple of really large aggregations, 30 or 40 individuals, and Oh, okay over here on this branch there's another really big aggregation. And on the farthest branch over there's another so there's probably 150 insects on this tree, and if we were up there in one of those concentrations there's probably complete pandemonium of signals.

AC: But right now I don't think you could hear it anyway, because of the wind blowing up there.

0.59.25 -1.00.42
RC: No, but in little, these little breaks we're getting between the wind there's probably a burst of signals

[AC and RC talk about neighbors dog]

RC: Okay, well that's a good spot where we could try to make some recordings, but it's pretty high up. So, I think we're running out of black locusts on this stretch but if we go up the road and on the other side of this hedgerow I think there's another... Oh here's another one... This is an older tree, and it just doesn't

AC: because it's an older tree it wouldn't be ...

RC: It might be, but -here's some ants, but there's -here's one female and an immature nymph and about 15 ants, so they're a pretty reliable guide to treehoppers but I don't think there are too many on this tree.

1.00.42 -1.03.27
A C : Now that, see that, this is a female treehopper and that's a nymph you call it. a young tree -is she the mother of that nymph?

RC: Probably not, she could be an older sibling, but females lay eggs over a period of about 4 or 5 weeks, and they lay them all up and down the stem here in these old leaf scars, where there are two thorns and the leaf has fallen off they lay there eggs right there, and then other females will come by and lay eggs in the same places, and then they move around the plant, so when you see a little group it's going to consist of relatives and non-relatives, and the fact that they're in groups of typically un related individuals may have some consequences for their social behavior. AC: In any even these are actually not the species of treehopper that you've done the work of finding this just amazing maternal care. RC: Right. These don't have any maternal care at all. They just lay their eggs into the plant, in scattered locations and leave them. And the eggs spend their winters in the stems and the eggs hatch out in the next spring, and in fact there are no adults around -the whole species exists only as eggs in the plant, and then only as nymphs and then the first adults come out, so in fact the first males of that spring generation are producing calls but none of them have ever perceived any of these calls, they've never interacted with adults. And most of the species, here's another female, most of the species in North America don't have parental care. But in the tropics parental care is really common. It's not really clear why -partly because there's many more species in the tropics, so you've got opportunity to have more absolute numbers of ones with parental care but it may also be the intensity of ant predation in the tropics, so for some way of dealing with them, or also not just of predators like ants, but also of egg parasitoids so, what's really common is for females to lay their eggs in a little clump in the bark and then they can stand over and they'll just stand there over their eggs for 2 or 3 weeks, and if a little egg parasitoid, a little wasp that's hardly bigger than the eggs comes around then they'll kick it off, brush it off.

1.03.27 -1.04.31 RC: and most of those then end up having the same kind of mutualism with ants, where the ants in a sense kind of take over the parental care cause the female will leave and the ants will stay there and take over the nymphs, in exchange for honeydew. Well let's AC: I just felt this ant biting me -it's indeed as you said, that the ants are defending the treehoppers. RC: These, yeah this is Formica, a genus of ant, and these are really aggressive. Actually these are I think pretty good mutualists for the treehoppers because they are very aggressive, and there are some other ants that wont attack you at all, in fact it'll just kind of run away, and probably aren't quite as good partners, but these are excellent because yeah, they'll attack anything that moves, including my finger or something inconceivably more massive than they are.

1.04.31 -1.05.07 RC: all right, well let's check, there's a couple small trees over there, let's check over on the other side of that road

AC and RC chat while walking across the road, looking at more black locusts ...

1.05.07 -1.05.53

RC: This is another species of ant, these are a different genus, Crematogaster, and what's actually neat is that they're building a shelter over the treehoppers, so if you look you'll actually see a little construction there that looks like a little mud, mud igloo, and there's one female on the outside there, one there, and then inside there, if we were to break that open, I can just let that one side, there will be other treehoppers and ants, and oh there're a couple that just hopped out -here are some other little mud shelters up here.

1.05.53 -1.07.15
AC: We should try putting our accelerometers on there [walking throughout this]

RC: When I first got interested in the species because of the interaction between ants and treehoppers and I was sure that there would be a kind of interspecies communication and I didn't find any evidence for it in this species, I have found some pretty clear suggestions of that in some tropical species, but I don't know if you've ever learned the name of Phil Devries, he's a tropical biologist who works on couple different families of butterflies, and the caterpillars of those butterflies are ant-tended. And have signals that function in attracted and maintaining ants around them, so ants themselves often communicate with vibration, so it's very, it's a very easy step I think for other things that are communicating with vibrations to begin communicating with ants in that same context.

1.07.15 -1.07.42
RC: Now we could try listening to some prematures, which are the ones that I would expect to be calling ants, because those are the first ones out in the spring, so when the ants come along and they're first finding groups of the very smallest nymphs that have hatched out, and if we got some signals from them that would be, really neat. So far I've never heard any.

1.07.42 -1.09.09 [walking and mic bumping] RC and AC talk about bam.

1.09.09 -1.11.43
RC and AC walking through woods, chatting. Locust leaf miners, looking for ants and
treehoppers. Lots of walking, some mic noise.

1.11.43 -1.12.46
RC: It always amazes me how just a little bit of knowledge about the behavior of these animals increases your effectiveness a thousand fold in looking for them, because if I had said, okay Alex, here's what these insects look like, why don't you go out and find some, and you know they live on plants and that was all, so you'd wander out here and be looking on every little stem and you'd probably spend 6 weeks before you'd actually find some. So there's a huge batch of locusts over there, young locusts that look very succulent and tasty but I don't, I've been over there and I haven't seen any signs of ants or treehoppers.

AC: Let's go back and see if the suns come around and lit up that branch that we're connected up to and see if we can get anything

RC: Okay, and if it hasn't then we might want to think about trying to see if we can get recordings from that other tree we found, that second one we found that has aggregations up at the top.

AC: yeah, okay

RC: Cause I bet there's a lot going on there.

1.12.46 -1.15.06
RC and AC chatting about the bugs in the original branch. Dog panting.

1.15.06 -1.17.59
AC: Rex, it's like being in a herd of tree hoppers because I can hear some right here beside me and then in the far pasture I hear them kind of lowing ... AC and RC listening to the treehoppers and commenting. Talk about moving the accelerometers...

1.17.59 -1.19.22
AC: ... When you are listening to this, I saw you before, suddenly you looked up there and you were looking at the stem and I think you were trying to see if there was something going on that you could see that might be associated with that sound _ can you?

RC: Well there's two different kinds of signals I'm hearing - one, these males have two different mate-searching strategies. One is to go walk along the stem and walk out onto the base of a leaf, beat their head against the leaf and then do that down sweeping whine (AC makes sound fx here), The other is to find a female, one of the females in these clusters, and walk onto the back of the female and to tap their head onto the field, but it's a rather different signal in both cases that they use, whether they're mate searching on the branch or on the female, so I can hear the signals of males calling on females, that's what I was looking up to see. And I can see here, there's a male right on the side of a female, and if you watch one for a while, you'll see that -beating their head on the side of the female just the way they do on the branch. And it's not as loud to us, because it's got to travel through the female and then into the branch.

AC: It must be pretty loud to her! [laughter]

RC: she's got a front row seat.

1.19.22 -1.21.46
AC and RC talk about the level and the signals.

1.21.46 -1.23.11
AC: You're being very careful, but even so, you are this incredible giant placing this thing right beside these creatures, within a couple of inches of them, and it doesn't seem to bother them.

RC: I think it does though -at some point if I were a little more clumsy about it, they would take off -it would be like a bag full of popcorn all exploding at once.

AC: So these all fly. These are flying insects although we haven't seen them fly.

RC and AC chat as they move the accelerometers around.

1.23.11 -1.25.51
ambi -birds, occasional dog panting, AC and RC listening to the treehoppers. Occasional comments by them. RC: I can see the males over here flying around calling on a branch -wait for a few seconds if they don't get a response from a female, they'll fly to another branch, fly to another branch. So there's a lot of calling over here. Here's a male that just flew in and landed ... RC and AC listening to the bugs. RC: Some of that purring is pretty close and personal .. I got very good up close signals.

1.25.51 -1.28.06 AC and RC listening to the bugs. RC: As I look across this tree there's about 6 or 8 branches I can see and there are males flying back and forth between all these branches, calling, waiting for a few seconds, and then flying off, landing on another branch calling, it's happening all over this branch -we don't actually hear it from where we are, it's too far through the plant, sound like here it may be a meter or two through the plant ...

AC: Is that cause there's a little more sun over there?

RC: I think so ...

AC and RC move back over to the other place.

1.28.06 -1.28.33 Walking in woods RC talking

1.28.33 -1.32.05 RC: ... especially in insects they're variable. So those males are flying around from tree to tree and some of the trees over there had very small groups of maybe two females and a male, and others had huge groups. So there's really really different social environments. And in some contexts these individuals might be cooperative say in forming aggregations to more reliably attract ants. In that case everybody has an overlapping interest _ everybody wants to aggregate, the ant attendants benefit, everybody benefits everybody _ maybe not the same way, because the ones on the edge might still be more vulnerable to predators than the ones in the middle of the group, but everybody's benefiting from an aggregation. But then when you've got males searching for mates, it's completely males' self-interest, and there's a complete conflict of interest between all the males that are out there looking for a small number of females, and so the that's one of the important parts of this social environment, is the ratio of males to females, and it's not so much the overall ratio but really the ratio of males that are ready to mate to females that are ready to mate, and females are only ready to mate at a very short period of their lives, and males are ready to mate, you know, as soon as they become adults, so you've got a really really biased sex ratio of lots and lots of males competing for a few females. And depending upon where the females are, they might be in the midst of a big group, or they might be solitary out on a branch somewhere, and so there's a tremendous amount of social competition, and then there's a huge amount of variation in their social environment. And if you listen to the signals of these things, or record lots of them, you find that there's a huge variation in their signals also. So if you have males that have been on a plant that only has a few individuals, they'll give a much simpler call, maybe skipping the tapping and just going rrrrrr rrrrrr, versus males that have been on a plant with lots of individuals will be doing more like what we've heard ta-ta-ta-ta rrrr rrrr, So there's a whole range of complexity of these calls which I would guess, it would be a place where I would look for adaptation to deal with that kind of variation in their social environment. And the way they perceive it is probably either by running in to or physically encountering -females, or by listening. And then you've got females also trying to assess you know they're ready to mate, and we don't know anything about choosing or being choosey about a particular mate in this species, but they also are dealing with very variable social environments. So when you look at something like this male mate-searching, when you try to understand it at least one way to approach it would be to look at as an adaptation to deal with a very competitive social environment. And they've got two really different behaviors, one is this, males walking out and not finding females at all but just essentially fishing, they're going out onto a stem and signaling, if there's a female there great, it there's not then go on to the next one, the next one, the next one, almost sort of, not blindly, but just searching space for females, and then the other one is walking on a branch, they encounter a group, and then they start calling and we get really different signals in those two contexts.

1.32.05 -AC: And there's a sort of a there's a It's not just sort of polar, there's a range of variations, you could be in a kind of a semi-crowded, when the treehopper comes from a large group, come to small group display large group behavior? Or

RC: At least initially they seem to display large-group behavior, but I don't know what happens, what I expect to happen is that that would probably change fairly rapidly, and the other thing is that it changes over time. So spatially we've seen, okay, there's really different social context on different plants, but if you follow the numbers of individuals over a season, these have two generations per summer, you start out with all immatures, which hatch into adults first. And it takes a few days for their cuticle exoskeleton to harden up. And become able to call and then shortly after that females become adults, and then the numbers, quickly changing day by day, and they reach a peak and then they drop over a period of 5 or 6 weeks, and even within a day you look at the number of males signaling, it will start off early in the morning with no males signaling and then you could have up to maybe a quarter of the male population signaling, and then dropping off again, so it's incredibly variable.

AC and RC listen to the tapes.

1.34.41 -1.34.59 AC and RC trying to set up accelerometers

1.34.59 -1.40.35 AMBI really good crickets, birds, frogs, in stereo.

1.40.35 -1.41.25 AC: I'm asking you about this goofy look that people get when they hear this, we're putting a headset on different people and everybody gets this same kind of goofy grin when they hear it. And why is that? RC: I think in part because it's bugs, and people don't expect bugs to do something like that, and because it's a sound they've never heard before, and part of it is just the sound itself, if it was a really boring sound they might not do it, but the sounds are crazy, they put together these really strange and different acoustic elements and odd combinations that somehow just make you laugh.

1.41.25 -1.42.37 AC: I will think differently about bugs forever because of this, but I'm just a guy who doesn't know much about bugs. Do you think differently about insects after what you've discovered?

RC: sure .. .r was never very interested in the idea of these insects that would communicate through grass stems, because I thought well, those signals are just going to be boring, and little wispy tappings, and I had no idea and the first time I listened to these treehoppers especially which seemed to have particularly bizarre signals, it completely expanded my concept of insect sound, and yes, once that happened I could never go back to thinking of insect sounds as just what crickets or katydids do -I love those sounds, I love listening to a chorus of crickets or katydids at night, but these are completely different.

1.42.37 -1.45.41 AC: It's not just that the sounds are so different, it's that the things that they're talking about, if you will, are things that I didn't think insects talked about. I had no idea that an insect young could call to its mother and say, hey there's a bully over here, come and do something about it. RC: Well, I didn't either, in fact, these studies with treehoppers are really the first time we've had a detailed look at any insects for communication between parents and offspring. The closest -see I would've expected maybe a complex communication system maybe in ants or in honeybees, that have these very famous well studied communication systems that allow them to do all kinds ..

AC: Big groups and they dance and they show each other where the stuff is and they lay trails and all that kind of stuff yeah. RC: But particularly for insects otherwise seem to have the most boring behavior possible of sitting on the stern of the plant and sucking sap and growing. To find that in fact they're constantly monitoring their environment and communicating about it to each other so that the end of a branch has a very active communication network and they're communicating in ways that at least in some context effectively unite a whole group of disparate individuals into a functional unit, like in a thorn bug family when a predator appears, the first nymphs spot it and then signal, and then signal sweeps through the whole group and even if the other individuals haven't detected a predator at all just the sound of signals from their other siblings, group mates cause them to chime in with their own signals and you get this whole group responding, which causes the mother immediately to come up and begin defending them, and this communication system is crucial to their biology, because maternal defense is really important to reducing predation, and if the mother disappears then you can lose the whole group quite quickly to predators. But it's not at all obvious, if you were just watching these things you might think well, okay they're just little bumps on a plant that are just sucking sap and nothing else. So it really

camera guy stops the interview.

1.45.41 -1.47.13 RC: The other things that are maybe, this is sort of a separate thought, but comparable outside of the bees and ants are caterpillars, tent caterpillars that have chemical communication systems that are analogous to the most highly social insects. There's a guy who's now ... But that's kind of neat too, because they lay silk trails, and if you watch ... [explains the chemical communication of tent caterpillars]

AC: we'll pick this up again tomorrow.

1.47.13 -1.48.22 AC and RC packing up the equipment with Ned.

1.48.22 CLAP SLATE (synchs also with accelerometer)

1.48.22 -1.50.22
Rex explains each signal and what it means (to be synched with the accelerometer tape) [lots of good ambi here]

1.50.22 -1.56.50 Rex continues to explain the accelerometer tape.

FROM 1.56.50 TO 2.01.57 COULD BE LISTENED TO MORE CAREFULLY

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