Short Wave - A Kazoo And The Evolution Of Speech

Episode Date: June 19, 2020

Encore episode. Researchers discovered that this simple instrument could offer insights into the evolution of human speech. Short Wave reporter Emily Kwong talks with primatologist Adriano Lameira about a growing body of evidence that humans may not be the only great apes with voice control. Read the paper he published last year.P.S. Sign up for our trivia night this Tuesday, June 23, at 8 pm EDT!Follow Maddie Sofia @maddie_sofia and Emily Kwong @emilykwong1234. Email the show at [e-mail] pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

Hey, everybody, Emily Kwong here. Maddie Safaya, too. We are hard at work on some really great new episodes. So in the meantime, we're breaking out an old episode you might have missed. That we both cherish. It really sealed our bond. I mean, Kwong, this is the episode that inspired my very first gift to you. How could I forget, Maddie Safia?

Oh, you've gotten better at that. So stick around past the end because we also have a very special announcement to share with you. all. And if you haven't subscribed to or followed Shortwave yet, first of all, how dare you? Second of all, we forgive you. Especially if you go ahead and do that right now. Yeah. Thank you so much. You're listening to Shortwave from NPR. Hey, everybody. Maddie Safai here with Shortwave reporter Emily Kwong. Hey, Maddie. Hey, you. So, Kwong, you've got a story today about the evolution of voicing. That's right. Featuring the voice of this guy, a primatologist.

Hi, my name is Adriano Lemaida. I'm an assistant professor at the University of Warwick in the UK. Adriano is one of many scientists chipping away at this long-standing idea that humans are the only members of the hominid family, the great apes, to possess what's known as active voicing. Okay, active voicing. Is that like my bossy voice? Not exactly.

Here, let me ask you, what would you do if you accidentally burned your hand, like set it down on the stove? Let out a little yelp. Okay. Adriano says he would yelp to. But that scream is rather uncontrolled. It's involuntary.

It's a reflex. It's something hardwired, similarly to laughter or a baby's cry. And so in that case, there is voicing, but there's no active voicing. And for decades, it's been thought that only humans demonstrated active voicing among the great apes. So chimpanzees, gorillas, orangutans could not voluntarily control their vocal cords. Got it. That was the theory. But that we, very special humans, could.

And that ability evolved fairly recently, like within the last two million years. A hot minute in Earth time. Yes. But Adriano wondered if this was true. And he used a pretty ingenious device to suggest that this may not be true after all. You're kazooing. Just to be clear, you've brought a kazoo in here for a reason. After studying orangutans these last 15 years, Adriano and his colleague Robert Shoemaker, president of the Indianapolis Zoo, published a recent study which suggests that orangutans

may have more voice control than we previously thought. So today on the show, if you give an orangutan a kazoo, can it produce a sound? We'll tell you about that experiment and how it helps us understand the evolution of speech in humans. All right, Kwong, you know I love experiments. Yes, you do. And this one involves a kazoo? And some orangutans. Okay, so orangutans are like the reddish-colored apes, right?

Yes, they're the ones with long arms, too, for their tree-swinging life. They're also very solitary and share 97% of our genes. Wow, evolution. So they're not as closely related to us as chimpanzees or bonobos before you get too excited, but they're definitely a relation. Like you get a holiday card relation. I would like to see the Christmas card you write to an orangutan, honestly. But you'd have to postmark it to Southeast Asia because these apes only reside in the rainforests of Sumatra and Borneo. They're endangered, their natural habitat threatened by deforestation and other human activity.

Adriano has studied them in the wild, but to isolate active voicing, he had to work with orangutans in captivity. Why is he so interested in active voicing? Well, it's been a polarizing debate within primatology. How much voice control do great apes have? And there's a growing pile of data from chimpanzee researchers, especially, that great apes do have some voice control. It's not just humans. And Adriano wanted to come up with a diagnostic tool to settle this debate, at least for orangutans. Gotcha.

But I imagine something like active voice would be super hard to prove. Oh, yeah. You can't open up an orangutan's mouth and say. tell it to say, ah, and see if the vocal cords are moving. It's not going to work like that. You could theoretically put the orangutan into an fMRI machine to observe if there's some kind of connection between the motor control area in the brain and the muscles and the larynx.

But doing that sounds very expensive, logistically complicated, and Adriano says it could be ethically questionable. Although this would be, say, the golden proof, we had to become more innovative to try to circumvent this situation because otherwise it would be literally impossible and it would remain in an unknown. But then, Adriano had a lightbulb moment. He realized that a musical instrument could be a way to monitor what's going on with the vocal cords of the orangutans in a non-invasive way. Which is the kazoo.

You're getting into it now, Sophia. So a kazoo, it's a type of membraneophone. So whatever oscillating air pressure is coming from your vocal folds, basically your vocal cords, will be mirrored by a thin piece of membrane inside the kazoo. It's a playful instrument in the sense that it's used in parties and by clowns in circus. So it basically distorts your voice. It exaggerates the intonation of your voice. And the kazoo presented two enticing possibilities to researchers. They could monitor the voices of a.

orangutans, but they could also check out their vocal control, so the frequency and duration of the sounds being produced through the kazoo. And then we would have this evidence for active voicing and therefore the evidence that their vocal capacities differ from our own, not in kinds, but in level, not in quality, but in quantity. So to test this hypothesis, here's one. But they did. Robert and Adriano worked with six orangutans at the Indianapolis Zoo. Okay. And three of them, Rocky, Nobby, and AZ can produce when asked this novel vocalization. It's like a signature call or sound that they make. So cool.

Yeah. And it's something they learned in captivity. And there are three other orangutans that don't have this special call. And all six of them were given the opportunity to play the kazoo. Okay. So do they, like, train them how to use the kazoo? Wouldn't that be cool? They don't, actually. It's important that they don't. Initially, all six orangutans were allowed to freely investigate the kazoo, which the paper says, quote, inexorably resulted in

the destruction of the kazoo. Sometimes you've got to smash a kazoo out there. Right. So they got that out of their system. And the researchers figured out something else. They gently placed the kazoo near the lips of these orangutans. Okay. And the three, Rocky, Nobby and Azee that had a novel vocalization, they were asked by researchers to make it, their distinct call. Okay, so what happened? Well, Rocky, he figured out how to use the kazoo in 11 minutes. Dang, they took me way longer than that. Don't feel bad, Maddie.

He comes from the entertainment industry. He really wants to please his human caretakers. And he has this novel vocalization that they call his wookie, like the Chewbacca character. So here it is. No, just on its own. Just on its own. Yep. That's the wookie.

sound. Then Rocky was asked to make the same sound, but with the kazoo touching his lips. Is that him playing the kazoo? That is. See, same sound. Beautiful. And remember, the only way to play the kazoo is to have control over your vocal folds. The kazoo will mirror your voice, so the orangutans are able to do that. It appears. Nabi figured out how to use her kazoo in 34 minutes. Pretty good. It's a respectable amount of time. Here's her novel vocalization, which they call her hug sound. Okay. I think it's cute.

All right, sure. Here's Nobby then through the kazoo. Somehow it sounds more aggressive. She's trying. And what about Azee? Aze struggled to produce his novel vocalization through the kazoo. Respect. Which the paper says involves a fast open-closed mouth movement,

which isn't really suited for serenading a person with a kazoo any. way. Right. It'd be like that sometimes. Yeah, it's true. So what's interesting, though, is the other two, Rocky and Nobby figured out different strategies for using the kazoo and got better at it within the hour. And this suggested to Adriano something important that the kazoo was an extension of their voice. And by manipulating the kazoo to sound more like themselves, they were demonstrating active voicing. And he recognizes this is a small sample size. Yeah, I mean, it's just two out of three orangutans, right? You would definitely want to reproduce these results.

Yes. Adriano said he would like to see his study expanded. Perhaps the orangutans can have more time with the kazzoos. But for him, the important and telling information is that these two orangutans were able to demonstrate active voicing at all. And to be clear, this is all happening in captivity, right? So he's not necessarily saying they're doing active voicing in the wild. No. In fact, you couldn't really do this study in the wild because those orangutans in those. in those rainforests, they have to be given a really wide birth when you're researching them. You can't go up and put a kazoo in their mouth.

Yeah, shouldn't probably. But this study does open the door for some really interesting questions and some bigger ones too. Like for Adriano, he thinks that what he's discovered with these zoo orangutans could say something very compelling about the origin of human speech. That the way we speak may have evolved more slowly than we think over the course of, say, 14 million years. And the orangutan is like our long-lost cousin in this shared ability to do active voicing. Long-lost by millions of years. Something like that. Of course, it would take a lot more research to identify a linguistic ancestor.

Andriano wants to find out, though, because that ancestor is potentially at the root of how you and I are speaking to each other today. When did that ancestor live? How did they communicate? Those are the questions that interest him. We owe a lot to language. Without language, we couldn't keep a society going. We couldn't transmit information or knowledge between generations. So it really what makes us distinct in anything that has ever appeared in the natural world, really.

I think you're distinct in the natural world, Emily Kwong. I'm glad I have my vocal chords with which to communicate with you, Maddie Safaya, Eraday. Would you like me to play you out? On your new favorite instrument, the kazoo? Absolutely. Yeah, let's do it. Oh, what beautiful kazooing. So you've been listening to Shoreway from NPR.

That's Maddie Safaya. I'm Emily Kwong. This episode was produced by Rebecca Ramirez, edited by Viet Le. Plus, Ted Mebain was the engineer for this episode. Thank you, Ted. Ah, the humble kazoo. Such a good instrument. And honestly, we aren't kidding.

After this episode, Maddie got me a silver kazoo engraved with my name because she is a very good friend and also a very competitive gift giver. Speaking of competition. Your favorite thing aside from facts. We will combine both of those beautiful things in our very first shortwave trivia night. That's right, nerds. Come join me and Emily Kwong on Tuesday, June 23rd at 8 p.m. for virtual trivia. We'll ask sciency questions. You'll give us, hopefully, sciencey answers.

It's going to be so much fun. And to participate, you've got to register in advance by going to NPRPresents.org, you and your whole team. That's NPR presents.org. We'll put a link in the show notes. See you there, nerds. Bye.