

We’re happy to share a special feature from our friends at Constant Wonder. Hosted by Marcus Smith, their "Mockingbirds" episode takes you through the complexity of mockingbird songs and why these birds mix hundreds of songs together using sophisticated musical techniques. Constant Wonder’s guiding principle is based on the idea that encounters with wonder and awe are real and spark a sense of mystery and surprise, and the show celebrates these experiences.
Darwin hated peacocks because he couldn't explain their excess beauty. He likely would have hated mockingbirds for the excessive complexity of their songs. Where many birds are content with a few simple chirps, mockingbirds learn hundreds of sounds from other birds and animals and mix them together using sophisticated musical techniques, the kind human musicians often employ. Their songs go far, far beyond anything necessary to find food, defend territory, or attract a mate. Why do they do it?
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Mockingbirds
[mockingbird sounds start]
Marcus Smith:
Mockingbird is mocking us. He's so much more advanced to get so much more what's going on in the natural world. The relationships between these bird timbres and rhythms, he's way beyond us. He's just making fun of us. People scratching our heads, trying to figure out what it all means. The Mockingbird might be the one who knows.
The Mockingbird is one of nature's first sampling artists or DJs, or like an electronic musician. He cuts and paste things together. He's doing exactly the same thing that electronic musicians are doing by cutting and pasting things from here and there, changing their speed, changing their pitch, changing their sound quality.
He hears an oven bird goes, teacher, teacher, teacher, teacher, teacher. And then he says, oh, well I, I'm gonna change that first phrase to a blue jay call and go, [imitating blue jay] like, that's kinda cool. And then I can put in something like a yellow throat, [imitating yellowthroat] and then it's some contrast. Put in a red tailed hawk [imitating red-tailed hawk call] it's like a whole phrase. It's all figured out. They do these things. And so I described that to some scientists. They go, what do you mean they do that? They go, yeah, just listen. That's what they're doing. He goes, oh yeah. Prove it.
[calm, uplifting music starts]
Marcus Smith: David Rothenberg is a composer, jazz musician, and the author of "Why Birds Sing: a Journey into The Mystery of Bird Song." He's a professor of philosophy and music at the New Jersey Institute of Technology, and that tells me that he's very likely the kind of person who would eagerly take up the challenge of describing, if possible, even proving what it is he hears in Birdsong. I'm Marcus Smith, and this is Constant Wonder.
[music fades]
Marcus Smith: At various times, Rothenberg has been found exploring the very outer limits of what's possible in the way of musical performance by playing his clarinet with animals, music-making animals like cicadas and whales. But we're gonna save those stories for a later episode. Today we're gonna sing a duet with him in praise of mockingbirds. Rothenberg has had an awkward relationship with mainstream bird scientists. I think you could call them "orthodox ornithologists." Ever since he published his 2006 book, "Why Birds Sing," that is where he issued them a challenge that frankly put many of their beaks on edge. Stop studying bird songs by tearing out the brains and syrinxes of birds, Rothenberg said, and start studying this from the perspective of the bird as a musician. I should let you know, by the way, a syrinx is what a bird has instead of a larynx.
Now, his challenge to them actually ended up cutting both ways. He was trying to call them out for their usual methodologies, but they threw it right back at him, which made him start to think... Let's get some
David Rothenberg: scientists together, come up with a study that might make them happy, because a musician has a very different criteria for truth. An artist has a very different criteria for truth and success than a scientist does. I can play one duet with a white-crested laughingthrush and say, oh, that's pretty cool. I like it. I think we got something there, and I can encourage people to listen to it and say, here's some music I made with this bird. But to prove that anything testable or duplicatable or, or repeatable happened there that really is a statistical significance, I gotta do it like a thousand times and measure what's going on. Now most artists and musicians say that's pretty boring, but those who want to study the musical phenomenon, well, they study things like that. So I figured if I collaborated with two different kinds of scientists, that I could really make some progress here and really show scientists that, you know, it's not just at the Mockingbird is, uh, using songs from hundreds of other birds. But the way he puts it together is very specific, an illustration of Darwin's idea that birds have a natural aesthetic senses. It's a perfect example of what he was talking about.
Marcus Smith: Do birds have a natural aesthetic sense? And if so, is that sense actually something you can observe in something like a mockingbird's song? If Darwin was thinking about this issue back in his day, when did the whole question go missing from the scientific discourse?
You know, another way to ask the question is this: where are today's Darwins who might risk making birds into artists? Somebody somewhere oughta be pursuing this still. If underpinning Darwinism is the whole bit about survival, you know what I'm talking about, go find food, don't die while you're at it and be sure to reproduce.
Is there any reason that natural selection should ever have resulted in any animals? Leisurely engagement? Pleasurable diversion? You know, something like the musical arts. Well hold on to these questions. We're gonna circle back to them. First, I want to consider what Rothenberg and his collaborators have been able to find in the musical structures, the musical habits that characterize the songs of mockingbirds.
David Rothenberg: They use so many techniques used by human musicians. When we decided to measure this, we tried to be very specific cause we knew how hard it was to do statistics on thousands of songs and phrases. So we just focused on the transitions, how the mockingbird moves one kind of sound to the next, and my hypothesis was that he doesn't change everything, he morphs gradually from one sound to to the next. And let's try and describe this in the simplest possible terms. Originally I had like 15 different ways he did this just by listening to them. Then 12 different ways. Then eight, we put it down to four and we figured out the four simplest ones we could demonstrate were happening most of the time. Cause you could statistically analyze that. That's how we figured that out. But it took three people with very different ways of understanding a natural phenomenon.
[sound of mockingbird]
David Rothenberg: So these four techniques are very common in human music, even in Beethoven. [hums the opening of Beethoven's Symphony No. 5] Same pattern, different pitch. You know, it's basic. Beethoven is doing the same things mockingbirds were doing. Now, he, he was in Europe, he'd never heard a mockingbird. If he had, he might have said, ah, he might have changed his pastoral symphony and it'd been way more complex if he had mockingbirds to reckon with.
[sound of mockingbird]
David Rothenberg: And today we recognize all kinds of noises and rhythms and beats as being musical. We can recognize all kinds of direct noises from natural sources, artificial sources can instantly be turned into music. And what mockingbirds do is they, they cut and paste sounds from the natural world, but the way they work with them most tellingly, the way they work with sounds is following these rules that we try to articulate and prove in a statistical way. We're actually there to make scientists happy.
[sound of mockingbird]
Marcus Smith: It'll be helpful here to bear in mind an important distinction: the difference between a bird call and bird's song. Some birds seem to emit only the kinds of sounds that perform specific functions conducive to survival. Others sing on and on and on with seemingly infinite complexity and with no apparent reason. So call and song. What's the big difference?
David Rothenberg: Bird calls are sounds the birds make that have very specific meanings, like, Hey, I'm hungry, or, watch out, there's a hawk flying overhead. And these sounds with specific meanings, interestingly enough, are often innate. The birds just know them. They're born with the ability to understand these calls and make these calls, but the songs in many species need to be learned. The little baby birds have to hear adults. In most species, just for a few months, they have the learning ability. In other species like nightingales, mocking birds, parrots, they have their whole life, they can learn new sounds. But learn the sounds they must. They actually have an ability to hear, listen to what they hear, and then learn to do. And these sounds are more complicated, they're more musical, they're more structured and shaped, and the function of them is usually thought to be to defend a territory or to attract a mate. That being said, what's in the songs is kind of separate from their function. Like a chickadee has a call, [mimics chickadee call], the bird's name is named after the call. The song is just two notes. [mimics chickadee call] then you have somebody like The mockingbird singing hundreds of phrases, copying other birds, learning from all kinds of different species. And its song has the same function: to defend a territory or attract a mate. Why does the mockingbird need something so complicated to do the same thing? Seems like a real waste of energy, doesn't it? Except the whole aesthetic of that species. The whole ethos of what it means to be a mockingbird involves having an incredibly complicated, ornate, unusual, weird song. That's just what that bird is about.
Marcus Smith: What a bird is about. This makes me think of the mysteriousness or wonder that is inherent in any living creature. Would this wondrousness evaporate completely if we finally figured out precisely what a certain creature is about? Its essential being, its core, its very nature. With what David Rothenberg just said, I think we're actually talking about a mockingbird's potential desire to experience beauty or take delight in the world, or its impulse to stay in the world for reasons beyond merely staying. Emily Dickinson famously wrote, "hope is the thing with feathers," and I think it's fair for us to ask with the philosopher, Rothenberg, is a bird more than just a hope for survival wrapped up in feathers?
You know, questions like this don't seem to come up very much in the biological sciences. At least not in my experience. It's just not easy to get a scientist to conjecture for very long about, oh, a bird's personal mission statement. Its sense of identity. Its, its purposes, its hopes, its dreams, its aspirations for quality of life. David Rothenberg seems to me to be just about audacious enough in this very nebulous realm to consider these things in the way that bridges to science.
I want to introduce you now to scientist, Dave Gammon, one of David Rothenberg's collaborators. They've been working rigorously to produce analyses of mockingbirds' sonic production, or if you dare call it music, go ahead, I don't care. Uh, Dave Gammon began his career in biology studying the humble chickadee. Rothenberg mentioned this species just a few moments ago. Now, the chickadee is a straightforward vocalist that pretty much sticks to a very basic set of calls and songs. To introduce Dave Gammon, here's the lowly chickadee, pumping out a few notes.
[sounds of a chickadee play]
Marcus Smith: How hard is it to switch lanes from the chickadee lane to the mockingbird lane?
Dave Gammon: [Gammon laughs] Um, it, it was challenging, I suppose. It was a lot of fun. I mean, it-, to some extent, one prepared me for the other. It's, it's all birds, it's all sounds, similar, uh, tools of analysis. So it was, it was a switch, but I wouldn't say it was the hardest thing I've ever done.
Marcus Smith: And a chickadee, I presume, has an impoverished repertoire compared to the mockingbird.
Dave Gammon: Oh, yes. Right across most of the country, the chickadee has a lonely repertoire of just one song type, and that's it. And where I did my research, which was in Fort Collins, Colorado, we saw the evolution of a repertoire. There were three song types. Not one, but three. So that was quite dramatic, we think. But, uh, mockingbirds have several hundred song types and nobody's ever really quantified it very well. If you try to quantify the number of song types that they do, it seems to me like a black hole. I've never tried to do that and I never think that I will.
Imagine if you were gonna listen to somebody speak English and you had no idea how to interpret English, and you had no idea how many words there were. And so you just start copying every single word that you hear, and you think you've got most of them because you're not hearing that much new. And then somebody pulls out a word like spaghetti and you're like, spaghetti? I've never heard spaghetti before. And then several minutes later you hear, uh, you know, let's say the word Bolshevik or something like that, and you think, I've never heard that. And then you go for a month and you are cataloging more and more english, but you never hear the word Bolshevik. Uh, for mockingbirds, they have a lot of words that are like Bolshevik that they possess, they will use. If you listen to them for hours and hours, you will occasionally hear these really rare song types. But you just never get to the bottom of the barrel. Um, the, the person who did the most work to, to quantify that as Kim Derrickson. Um, he did this amazing study where he quantified the number of song types as well as anybody ever has for mockingbirds. And he figured out that about 25% of their song types are sung only once in this sample. He has exhaustive sample of thousands and thousands of songs.
Marcus Smith: So maybe the very project of assembling a grand catalog, an encyclopedic, uh, collection of these songs is just not the analysis that is gonna be attractive in the end
Dave Gammon: . Well, it's not the analysis that I've attempted , but it's, yeah. I mean, if somebody does it, I'll be very interested to see what they come up with. I expect it's gonna be hundreds and hundreds, maybe even thousands of song types, but, I don't anticipate that anybody will do that study anytime soon.
Marcus Smith: You know, there are things to do with language if you're studying it, besides just looking at dictionaries on lexicons. You could look at poetry, you could look at stories. There's lots of things you could look at. So what are you looking at in mockingbird song?
Dave Gammon: Right. So the fact that bird song is called song is kind of anthropomorphic and it, uh, gives an interesting suggestion of how you might look at bird song. So that was what led David Rothenberg and Tina Roski and I, to examine mockingbird song as a musician, a musicologist would examine human music. So, that was a lot of fun with that and we found that mockingbirds use these compositional techniques. That's sort of like what a composer would call variations on a theme. So we were able to show that that exists in songbird.
Marcus Smith: So the song of a single mockingbird isn't going to be consistently the same? They're going to tweak it and it's going to morph and it'll go through different variations?
Dave Gammon: Absolutely. If you listen to a mockingbird, you'll hear them tweak. Uh, they'll go from one song type to the next, but there's often this really cool acoustic relationship between successive song type. So it will be similar to the previous song type, but different in one characteristic way, such as the pitch went a little bit higher. [mimics a tweeting sound, from low to high] something like that. Or they might bring the pitch lower, or they might change the timbre a little bit, the sound quality of it. They might, stretch out the notes a little bit. And these subtle but musical, compositional techniques are used by mockingbirds anytime they sing.
[mockingbird call]
Marcus Smith: The call in my mind has a function perhaps that can be deduced by us humans, but maybe a song, not so much?
Dave Gammon: Um, no, songs have functions. They're just um, they're more complicated. So the way to think of it is, calls are short, songs are long. Calls have a clear function. Songs are, um, well, they all have clear functions. Songs are about breeding and, uh, In mockingbirds, they're about breeding, trying to impress a female mockingbird or to stimulate her in some way. In many other songbird species, songs can also be about males fighting with other males, but calls have a variety of functions, whereas songs have just a limited function. Um, there are some exceptions, but that dichotomy of songs and calls works fairly well for a lot of songbird species.
Marcus Smith: How confident are you that all songs you know, these universal statements are always risky, but, , all songs have functions.
Dave Gammon: Um, I, I'm not 100% confident of that at all, Marcus. So I think that it's safe to assume that most of them. But occasionally maybe they just ramble a little bit. I mean, sometimes I'm walking around the house cleaning and I start, something spills outta my mouth and there was no function at all to it. So why couldn't a bird do that?
Marcus Smith: You know how a cat plays with a mouse sometimes. It's not necessarily all about eating the thing that's, you know, there could be a diversion going on. There could be entertainment perhaps in the song. I don't know.
Dave Gammon: Yeah. And that's, that's a neat idea because, Darwin, actually the study of bird song was referred to by, uh, Charles Darwin, and he thought that bird song from a bird's perspective was probably a very aesthetic thing, which just subjectively that they like listening to it, sort of the way that people will listen to music while they're cleaning or doing their homework or something. That hypothesis of Darwin has never really been followed up on very well in the bird song community. I think part of it is that a lot of the STEM people are just not that interested in arts and humanities.
Marcus Smith: So what about you though? Are you inclined to think, I'm gonna make a little room for this idea of an aesthetic kinda bird song?
Dave Gammon: Right. I'm sort of the anomaly in there. It's fun going to the scientific meetings and talking about the bird song from a musical perspective, for me it seems fairly natural. Um, I was a music minor when I was an undergraduate at BYU. I still remember being in the Wind symphony with David Blackington and being on the marching band field and all that. And it was a lot of fun. But I think a lot of the scientists that go to meetings with me, they don't do much with music. They don't sing, they don't hear a lot of the things in music that I would hear. So they're just not as familiar with it. And I think it's not so much that they're anti art or anti music, it's just not a -- they don't see the relevance of it as well.
Marcus Smith: So when you meet somebody like David Rothenberg then, who is a musician, and he is also interested in bridging over with his music to the animal kingdom and what animals are generating in the way of song, so-called. What do you make of somebody like David? Are you immediately inclined to say, oh, a scientist can hang with .
Dave Gammon: Short answer, yes. But I recognize that he is an anomaly in his world for him to say, oh yeah, music can be found in non-humans. Sure. In animals, no problem. I can even communicate with them And so he'll, you know, connect his clarinet up to some hydrophone and then try to perform a duet with a whale. That is funky and that is not normally done in the musical world.. And so he, by venturing into the biological world, is sort of an anomaly in his world, and I, by venturing into the musical world am kind of an anomaly in my world. So that's why he and I get along so well.
Marcus Smith: Well, are you finding some kind of foundation where there's a synthesis going on between your two different disciplines?
Dave Gammon: Sure. But I think that that synthesis is coming along pretty slowly. There's really not a lot of people who look at animal sounds as if they were a musical thing. And so, um, yeah, it's wide open to try to discover that, cause I don't feel like that we as a scholarly community have a good -- we haven't really wrapped our heads around it yet.
[bird call sound]
Marcus Smith: Dave Gammon, David Rothenberg, and a third collaborator, Tina Roeske, may be sailing in mostly uncharted waters here. And so they've decided to make a few charts of their own. For one thing, they've already mapped out some very specific techniques that are used by mockingbirds in their sonic production. I say sonic production because frankly now I'm a wee bit nervous about calling it music. Even just calling it bird song seems a little bit risky. Stick around if you want to explore this handful of techniques a little later on with Dave Gammon. He's gonna give us an audio guided tour through the aspects of pitch, timbre, and tempo. All of these three things manipulated by mocking birds in their very adroit mimicry. Right now though, we're gonna put our ears to some of the more basic aspects of how a mockingbird mocks. We're also going to test our ability to distinguish between a virtuoso mockingbird and a rank beginner.
[mockingbird chirps]
Marcus Smith: Well, I do have here with me some clips. You knew that I'd be coming with some bird calls or sounds. Aside from the amphibian that we're going to hear from. These are, these are mocking bird sounds. Here's two sounds and I'll play 'em back to back and you can explain for us, okay, here goes.
[Two sounds play, one of the Pacific tree frog and one of the mimicking the frog]
Dave Gammon: The first sound was the ribbit call of the Pacific tree frog. The second one was a mockingbird mimicking the Pacific tree frog.
Marcus Smith: Have you nailed that down? You know, that that was actually the Mockingbird borrowing the sound from that amphibian?
Dave Gammon: There was no question in my mind that that second one was a Mockingbird imitating a frog. This is a study that I did with Anna Corsiglia, who was an undergraduate at Elon University with me. And she memorized dozens and dozens of frog calls from all across North America and then listened to dozens and dozens of hours of song from mockingbirds. That was definitely a mockingbird imitation of a frog.
Marcus Smith: Why would a mockingbird want to imitate a frog ?
Dave Gammon: Nobody knows that, but we know that they do. I can think of several hypotheses. Uh, mockingbirds are generally not speaking with frogs as far as I know. They copy the sounds of frogs, but the frogs don't listen to them, and they don't listen to the frogs. Who is listening is the female. So it could be that the female is particularly impressed by a wide variety of sound. And what could be more variable than to mimic several species besides yourself and even some non bird species such as amphibians. So that would be my best hypothesis, but we've never done a study to prove that that's what the function is..
Marcus Smith: Am I to understand that this mocking bird, the male, is behaving like a strutting peacock and instead of lots of feathers, the male comes equipped with lots of sounds?
Dave Gammon: I think that's a great analogy, Marcus. Sure. A mockingbird is a peacock with songs, mimetic songs, instead of feathers coming out. Great.
Marcus Smith: Let's go on to the next sounds here.
[two sounds play, one of the Cope's gray treefrog, and another of a mockingbird imitating it]
Marcus Smith: Same trick?
Dave Gammon: Yes, yes, but that's not a mockingbird in California like the last one. This is a mockingbird from my home turf here in North Carolina. And we have a different set of frog species. The first one you heard is called the Cope's gray treefrog, and the second one was a mockingbird imitation of it.
Marcus Smith: Okay, help me out. Tell me a little bit more about why, other than just being able to observe this, and record it, and maybe write some kind of an article about it where it's been observed and documented. Does it go beyond that for you?
Dave Gammon: Maybe, so the story of how this study came to be is a really fun one. I was in Canada at a scientific conference and I was listening to a friend of mine present on something completely unrelated. When suddenly it hit me that a study that I just published on Mockingbird, imitating other bird species could be applied to more than just birds. The finding that I hadis about a topic called model selection. So it's if you are a mimic, then you hear all these things, you hear squeaky wheels and you hear trains going by and you hear cars, and you hear whistles, and you hear lots of birds. How do you know what you're gonna mimic? You've got this incredible capacity to imitate. So what are you going to mimic? And what I found in this earlier study, gamin 2013, is that they mimic the sounds in their environment that already sound similar to the sound, to the non mimetic sounds that they make. And that worked pretty well for the birds. But in the process of doing that study, I'd noticed that mockingbirds around here imitate a copes gray tree frog. And I started thinking, do they mimic other frogs? And I thought, well, they only rarely mimic Copes gray tree frogs, but mockingbirds imitating frogs, that's kind of cool.
So I talked to some friends about it and they said, yeah, you know, we can help get you some recordings. So, my student, Anna Corsiglia and I formed this really amazing network of friends all across North America and we were able to collect mockingbird sounds. Not just from North Carolina and Texas where I had lived, but from all across the country. And we were really excited to test the hypothesis from my earlier study, and it ended up fitting really well with the frogs. So they were more disproportionately likely to mimic the frogs that already had the right kind of pitches, the right kind of tempo. And in some cases they even modified the frog sounds. When the toad itself sings, it'll go [mimics trilling sound of toad] And then it'll go on for another 20 seconds. Something like that. Well, there's no way that a mockingbird could sing for that long. So they go, [mimics trilling toad sound three times] so they do just the first part, which is all they can do with their breath supply.
Marcus Smith: So I'm gonna do a little recap here just and, and you tell me if I'm getting this right. If there are sounds made by other animals, I don't know how wide that net goes, if it includes squirrels and armadillos. I don't know. I don't even know if an armadillo makes a sound for that matter. But if animals around them that are, they're in the proximity of other creatures, and if those other creatures are making sounds, they might be tempted to imitate those sounds, if, and maybe only if, it's within the scope of their vocal apparatus.
Dave Gammon: So this is a finding that applies to mockingbirds. I don't know if it applies to other species. I think probably not because the ability to imitate another species is pretty rare. Most songbirds like chickadees or towhee that you mentioned earlier, they are not going to imitate another species. But mockingbirds can do it. Starlings can do it. Blue Jays can do it. Crows might be able to do it. So there's just a handful of species that do it. Um, I have some friends in my scientific circle who have looked at model selection in other mimicking species such as the liar bird of Australia. And my hypothesis of imitating the sounds that already sound similar, doesn't seem to apply in the liar bird. So it might be just a, mockingbird rule.
Marcus Smith: So if it's a rule, then a mockingbird is absolutely disinclined to imitate, if it could even hear it, the song of a whale or an elephant. Or a lion. It has to be within their zone.
Dave Gammon: Right. It has to be, can't be too high. Can't be too low pitched, can't be too fast. So like a junko, they do this really fast trill thing. Mockingbirds are never gonna imitate it, it's just too fast for them. And then there's some things that are just too rambly for them, like a robin. If you wake up, and I'm sure you'll hear this in Provo, you wake up at 5:00 AM and the very first bird calling is probably a robin, as it sings its song. Well, its song is just jumbled up [whistles the song of a robin]. You know, it's like every sound is different from the previous one. But in mockingbirds, they have to repeat it. So it's like [trills the song of a mockingbird] something like that. And because robins don't make a repetitive sound, they're ignored by the mockingbird. But robins do make a call that sounds more like [trills the call of a robin], something like that. Well, that's repeated. So mockingbirds will imitate that.
[the sound of a mockingbird imitating the robin call plays]
Marcus Smith: Yeah. I'm just looking for the candy that the mockingbird is going after, you know? I'm looking for what really is appealing there, of course. But it has to do, it has to do with their... I don't know, aptitude, or their apparatus. What they can do, they'll try to do.
Dave Gammon: Yeah. So in, in, in a very broad sense, this is just rules for how learning takes place. So when we humans are learning our song, our language, then we disproportionately pay attention to certain kind of sounds. For example, if they come from parents, other humans. And then we disproportionately ignore sounds that don't fit, those cues that we're looking for. So mockingbirds are learning their songs just like humans are learning our speech. And mockingbirds have rules that governs what they pay attention to and what they're willing to learn from.
Marcus Smith: So now that you've talked about learning, and that has to do with whether they're humans or mockingbirds, we're talking about juveniles versus adults. We do have some samples of, different types of Mockingbird songs drawn from different, uh, parts of life stages. I guess I'll play three different samples of mockingbird songs and I'm gonna call them A, B, and C.
Let's listen to them each individually and you can guide us through what's going on here. Here's A.
[mockingbird sound plays]
Marcus Smith: Sounds like that bird's jumping around from different, you know, kinds of little tricks.
Dave Gammon: Absolutely. So, Marcus, that A is sung by an older male, an older male Mockingbird. If you listen to it carefully, you can see it's highly stereotyped, that it repeats a sound many times in a row. And when that happens, that signals to anybody listening such as a, a female that might want to be impressed by a male that he knows how to repeat sounds well. He has a well refined song. That kind of sound also contains more mimicry than less refined song. If you listen carefully, between A and B, B is gonna come across as a little bit less stereotyped.
Marcus Smith: Well, let's hear it.
[another mockingbird sound plays, this one less organized]
Marcus Smith: That sounded to me like a tentative bird.
Dave Gammon: Right, yeah. And that tentativeness is a lack of stereotype. If it's[mimics sound B] you know , it's just repeating exactly the same way over and over again. That's highly stereotyped. So that second example is maybe it's not as old of a bird, or maybe it's a bird with a less refined song. I assume that a female would be less impressed by sample B.
Marcus Smith: Well, I certainly was less impressed. [Smith and Gammon laugh] With your help, you're guiding me through this of course, Dave, here's my last sample, and maybe this is Goldilocks in between young and old. I don't know.
[a third mockingbird sound plays]
Marcus Smith: What have we got there?
Dave Gammon: So hopefully you could hear that there's really not a lot of stereotyping to that. There, there is some attempt to repeat syllables, but it's kind of buzzy. It's just not very stereotyped. There was not a bit of mimicry in that very, in that last one.
Marcus Smith: So it's an undisciplined bird. It's a lazy bird.
Dave Gammon: Um, I think better than lazy is a young bird. So the mockingbirds, they hatch for the first time in the spring, and then the babies don't make any singing at all for several months. So what you heard is probably the first few songs of an individual. So meaning like, it probably just started trying to sing maybe a couple or three weeks earlier than that.
So it's just really un stereotyped song, no mimicry in there. It'll get better and probably within a month or two he'll be singing better than that. But that shows some of the developmental progress that males have to make in their singing before they'll ever impress a female, get a mate, have kids.
Marcus Smith: Well, I wanna go back now to this interesting, uh, foray that you have made, an excursion kind of away from your scientific discipline into the artistic realm. And you've done this with David Rothenberg and Tina Roeske. You each come with different things to add to the, to this recipe. What have you been aiming for as a team?
Dave Gammon: Right. Uh, we would like to get a very interdisciplinary understanding of bird song as a musical phenomenon. So my role was to be the naturalist, the one who goes around chasing birds in their natural habitat and understands what's going on in the ground, on the trenches.
Tina Roeske was amazing at doing this signal analysis. So she would make these fine grained acoustic measurements that, uh, then she assessed with complex statistical analysis and she is also trained in neuroscience, so she could look at things in a very technical lab-y sort of way. And then David Rothenberg is trained in more of the arts and humanities tradition. And so he could examine the notes from a musical perspective and bring up insights that wouldn't come as naturally to me as a scientist.
Marcus Smith: It seems to me that there's an issue here of freedom in a bird. The whole question of instinct or, uh, maybe is it just utter randomness of imitation? Or is there any kind of self-awareness? How would we ever know that about a bird? Whether a bird is self-aware, to the point that the bird could say, well, right now I've gotta call a mate. Or, well, right now I'm just practicing my songs. Or right now I'm just having fun. I don't even knowhow anybody could tease that out with any kind of a basis for making any claims about it.
Dave Gammon: [Gammon laughs] What we need is to train the birds how to speak in English so they can tell us for themselves. . Oh my goodness, yes. I mean, you've hit on the million dollar question, how to understand the intense and perceptions, the subjective perceptions of a bird. Because we're thinking about that all the time. The paper that Tina and David and I did, we're very transparent that we're focused on human perceptions of the bird song. It would be so much better and so much more convincing if we could look at birds' subjective impressions of the bird song, but we just don't have the tools for that yet. So when you get ideas for it, let me know and we'll become famous.
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Marcus Smith: Dave Gammon has become my favorite mocking human . He makes those bird call sounds with, with such panache, you know. He has a vast repertoire when it comes to imitating bird calls and songs. Well, in the forthcoming episode, we're gonna circle back again to visit with David Rothenberg some more, whom I also greatly admire. We'll talk with him about making music together with whales, cicadas, and other non-human makers of sound. And in just a moment, we're going to dive into today's. promised bonus feature. That's an audio guided tour with Dave Gammon sorting out with some greater precision what it is a Mockingbird does an altering pitch, timbre and tempo to generate their songs.
David Rothenberg is a professor of philosophy and music at the New Jersey Institute of Technology. David Gammon, the Professor of Biology at Elon University. Our thanks to both of them for sharing their time and expertise. This episode of Constant Wonder produced by Eric Schulzke with Paige Krumperman Darrington. Thanks to Parker Schmidt and the BYU Broadcasting sound design team. I'm Marcus Smith, for Constant Wonder.