Short Wave - If You Give An Orangutan A Kazoo...

Episode Date: December 6, 2019

If you give an orangutan a kazoo, will it produce a sound? Researchers discovered that this simple instrument could offer insights into the vocal abilities of orangutans — and 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. See 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, hey there. This is Emily Kwong, shortwave reporter. You know, I feel really lucky to be working on this show. It's full of incredibly talented people. We get to interview such a diverse array of scientists doing fascinating, cutting edge work. It's a scientific take on the news. Where are you ever going to get that anyplace else but NPR? We love making it for you. It brings us so much joy. But in order to keep doing it, we need your help. Because this podcast is a product. of public radio. So to keep it coming to you each and every weekday, we're asking you to go to donate.npr.n.org slash short to find your local public radio station and give. Even a little bit really helps. Again, donate.npr.npr.org slash short. Thank you so much. You're listening to Shortwave from NPR. Hey, everybody. Maddie Safai here with Shortwave reporter. Emily Kong. 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 longstanding 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 action.

voiceing 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 that. like active voice would be super hard to prove. Oh, yeah. You can't open up an orangutan's mouth and 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 light bulb 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. of membranophone. 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 read. researchers. They could monitor the voices of 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 what 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 AZ, 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.

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 Aizzi? Aiz 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 the kazoo anyway. 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 kazoo's. 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 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. Adriano 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 cords with which to communicate with you, Maddie Safaya. Erridae. Would you like me to play you out?

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 Mebane was the engineer for this episode. Thank you, Ted. We'll see you next time.