Short Wave - What are sperm whales saying? Researchers find a complex 'alphabet'

Episode Date: May 20, 2024

Scientists are testing the limits of artificial intelligence when it comes to language learning. One recent challenge? Learning ... whale! Researchers are using machine learning to analyze and decode whale sounds — and it's just as complicated as it seems. Curious about other mysteries of nature? Email us at [e-mail]. 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

You're listening to Shortwave from NPR. Hey, short wavers, Regina Barbara here. So when I think about whale songs, I think this. But not this. That's a family of sperm whales. Here today to tell us more about this whale conversation is NPR's climate correspondent Lauren Summer. Hey, Lauren, welcome back. Hey, Gina.

So, Lauren, I'm not going to lie, this whale chatter kind of sounds like bike spokes to me. Yeah, I kind of get like Morse code combined with microwave popcorn. Microwave popcorn. I need to eat lunch. Okay. So hearing these sounds makes me wonder, like, are these whales really talking to each other? And like, what are they saying? Yeah, what is happening there? You're not alone in wondering that. It's kind of this age-old question. Like, what are animals saying? Right, of course. Yeah, and especially whales, because sperm whales have big brains. They have close family groups. And they cordoned. a lot. They dive together, they hunt together, they even babysit for each other. Shane Garrow, who is a sperm whale biologist, who has spent years with these whales, he says he sees that kind of family

dynamic all the time. It's hard not to see cousins playing while chatting, to not see moms hand over to a babysitter and exchange a few words before sort of walking out the door, so to speak, to go eat in the deep ocean. Oh my gosh. I can relate to this. a lot as like the older cousin babysitter and as a mom. But as someone who has listened to a lot of audio, these sounds sound pretty complicated to decode. They have so many clicks. Yeah, it sounds pretty messy.

It's not easy for us to figure out. But that's where computers are coming in. Researchers are hoping artificial intelligence could tease out what the whales are saying. And as a first step, they figured out a sort of sperm whale alphabet. Ooh, okay, an alphabet? So this is starting to sound like a language. Language. Okay, that's the tricky word here. It's kind of a tough question. There's been a very heated debate for years about whether animals can have language or whether that's something special that only we humans can claim. So today on the show, how technology is helping us figure out the mysteries of animal communication. And if we could figure out what sperm whales are saying, should we try to talk to them? I'm Regina Barber, and you're listening to Shortwave, the science podcast from NPR.

So Lauren, sperm whales are somewhat famous for being like in Moby Dick, but what are their lives actually like? Yeah, so sperm whales are divers. They're the size of a school bus, they're kind of those, you know, those big foreheads, for lack of a better term, foreheads. And they spend most of their time diving in the deep ocean searching for their favorite food, which is squid. Me too. They can go thousands of feet below the surface. And so Shane told me they are in the dark a lot. So sound is everything to sperm whales. In the darks of the deep ocean, these are places where sunlight never gets to. So they navigate their world through sound, just like bats in the dark sky, they use echolocation. And they use sound to stay in touch with one another and coordinate with the families in which they live.

Wow. Yeah, it's also just hard to see underwater, right, in general. So I can see how sound would rule almost like everything. Yeah, yeah. And they live in these tight-knit groups. They're female-led. So there's grandmothers, mothers, and daughters. They all stay together their entire lives. The males get to hang out until they're adolescents and then they have to leave to head out on their own. I totally would love watching like these whales family dynamics. Right. Yeah, because they live a long time. And Shane studies these whales in the Caribbean. with the Dominica sperm whale project. He knows these families, and they vocalize a lot. They have long exchanges with each other. It's not rude in sperm whale society to talk at the same time and overlap one another.

It sounds like an extended family, like loud summer barbecue. Yeah, a lot going on. It sounds kind of messy. But actually, all those clicks can be broken up into patterns of clicks. ones that the whales use over and over. They're called codas. One that's really common in the Caribbean is the one plus one plus three coda, which sounds like this. You know, one plus one plus three. Sounds like a salsa dance. Yeah, it's cha, cha, cha, cha, cha. Yeah, it's cha cha, cha, cha. Yeah. So what sounds like a whole bunch of like clicking is actually like these discrete units, these discrete

chunks. Yeah, yeah, all kind of strung together. And family groups can have dozens of these different codas. They all have a different number of clicks or a different pattern of clicks. And researchers like Shane, you know, they've been recording these for years because they've been trying to tease out the patterns and how the whales use them. And more recently, they teamed up with artificial intelligence researchers in a collaboration called Project SETI. And their goal using that technology is to decode what the whales are saying. So AI has been learning human languages and researchers are trying to like test the limits of what it can do, but learning whales seems really complicated.

For sure, yes. You know, they kind of took this first step where they used machine learning to analyze more of 9,000 recordings of sperm whales. And Danielle Roos, who directs MIT's computer science and artificial intelligence laboratory, she told me it was key to use computers because it could find clicks that humans couldn't find on their own. It really turned out that spermwell communication was indeed not random or simplistic. but rather structured in a very complex combinatorial manner.

They found far more variation than researchers thought there was. Like, Shane says sometimes it's the same coda, the same set of clicks, but they make it slightly longer. So that one plus one plus three coda we talked about might be half a second long or it might be 1.3 seconds long, nearly three times as long, right? And the same whale will make short ones and long ones and different families will make short ones and long ones. Which kind of sounds like this.

That's subtle, right? Yeah, to us humans. But wheels actually pick up on these differences and they even repeat them back to each other. So, you know, sometimes it's the tempo of the clicks that's different. Sometimes the whales throw in an extra click at the end of the coda, Daniela says. And this was very interesting. We started wondering, is this extra click sort of like the end of a sentence or something else? And doing this analysis, they identified what they're calling the sperm whale phonetic alphabet,

which catalogs all these variations. It's actually making me think, like, what if they're slang? We're, like, with the different family members. Okay, if we're using, like, the word alphabet, that, again, makes me think of language, like, are all these different codas different words? Are they, like, parts of words, you know, like the sounds that make up an alphabet? Right. And that's what's hard to figure out, because the thing that researchers say is exciting

is that these codas don't seem to be random. They can be predicted by machine, learning in the same way in which you might predict the sequence of syllables or the sequence of words in a sentence. She's saying there could be a possibility of recombining these codas to make meaning. And that's something we do as humans in language, right? We take sounds that don't really mean anything on their own, like short, right? Short becomes short.

And we combine it to make something that has meaning. Okay, but like just because you understand like the rhythm of the click, doesn't mean you might understand, like, what they mean. So could scientists understand what the sperm whales mean? Like, how could they prove sperm whales are conveying complex things like language? Yeah, that's really hard to do. Shane says they're working on recording sperm whales and observing their behavior at the same time to kind of build up a data set. But, you know, it's kind of hard to know if you're capturing their world and what's important to a sperm whale in that moment.

If we only ever studied North American English-speaking society in the dentist's office, first of all, we'd walk away with the fact that the key part of their communication system is the word root canal, right? And we'd just be wrong because we didn't have a comprehensive picture. Yeah, I mean, that's a really good point. And those are two words in a dentist office I'm really actually scared of. Yes, very much so. And it kind of just shows like we're used to looking at things in a very human-centric way. And people have been debating this animal language question for a really long time. It goes back, you know, 1970s researchers were teaching chimps and gorilla sign language, you might remember. Yeah. And the question was whether they were copying us or really using language the way we do. And there's a lot of other examples.

Like bees, you know, they do that special waggle dance in a hive. It tells other bees, like how far are the flowers and what direction they are. And I talked to Taylor Hirsch about this. She's a researcher at the Marine Mammal Institute at Oregon State University, and she studies sperm whales. Some of what they're doing may be totally different from our way of communicating, and we're probably never going to be able to fully grasp those differences. So I think there is value in seeing if patterns in animal communication mirror patterns in human language. But I think it's important to remember that perhaps just because we don't find evidence of something

doesn't mean that that system isn't complex in ways that we don't understand. Right. Like, can our human brains comprehend whatever system these sperm whales have worked out for themselves? Like, it actually makes me think of like a rival that film. Oh, yeah. But all we really know is how our own language works, right? And that's, I guess, where we start. Yeah. And researchers like Shane, he agreed that looking for those similarities is valuable. You know, when we can talk about whales and how important their grandmothers are or how important being a good neighbor is or learning from different cultures is and the important. of cultural diversity in society, that really sort of resonates with people and can drive change in human behavior in order to sort of protect the whales. And, you know, sperm whales are still coming back from commercial whaling where their numbers were just decimated. Today, they face threats like ship strikes and plastics in the ocean. So Shane said it's important to appreciate what they share with us because we have such a big

impact on their world. So if artificial intelligence figures out, out sperm whale language, what's the next step? Like, are researchers hoping to talk to them? Yeah, it's kind of an ethical question, right? Like, do you play some sounds back to sperm whales to try to say something to them? What does that do to them? Especially if we don't really know exactly what we're saying to them. Right. Like, are we going to scare them? Like, I would be a little worried. And do we want to, like, hear what they say back to us? Like, humans, they might not like us. Leah, we don't have a great track record. Right. And, you know, everyone I talked to in reporting this, all these researchers told me they get asked a lot of what they would want to say to sperm whales. And Taylor told me, you know, she's not like wearing to go on this. There's this implicit, like, do I have the right?

What gives me the right to say anything to them? I mean, sperm whales have been communicating with each other a lot, long. than humans have, right? They've been doing it before humans had language. So clearly they've got it figured out on their own. Wow. Lauren, thank you so much for communicating all of this to all of us. Thank you so much. Yeah, thanks. Before we head out, a quick shout out to our Shortwave Plus listeners. We appreciate you and we thank you for being a subscriber. Shortwave Plus helps support our show. And if you're a regular listener, we'd love for you to join so you can enjoy the show without sponsor interruptions. Find out more at Plus.

NPR.org slash Shorewave. This episode was produced by Rachel Carlson and edited by our showrunner Rebecca Ramirez. Lauren checked the facts. Patrick Murray and Stacey Abbott were the audio engineers. Bet Donovan is our senior director and Colin Campbell is our senior vice president of podcasting strategy. I'm Regina Barber. Thanks as always for listening to Shorewave. The Science Podcast from NPR.