Denise Herzing: Do Dolphins Have A Language? We know that dolphins make distinctive clicks and whistles. But is that a language? Researcher Denise Herzing thinks it might be — and for the past 35 years — she's been working on unlocking it.

Denise Herzing: Do Dolphins Have A Language?

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It's the TED Radio Hour from NPR. I'm Guy Raz. And on the show today, Anthropomorphic - ideas about how we interact with animals and how those interactions help us understand the world and our place in it. And for our next Ted speaker...

DENISE HERZING: So I'm Denise Herzing.

RAZ: Animal interactions have been her life's work.

HERZING: I'm the research director of the Wild Dolphin Project, and we work in the Bahamas.

RAZ: I've seen lots of pictures of you underwater, holding a camera. When you're down there...


RAZ: Does it feel like it's almost like - I don't know - like, just a better place to be? I don't - do you ever get that feeling?

HERZING: Well, you know, it's an immersion into a three-dimensional world. You know, the tides and the currents and the salt and the waves and - I mean, that all feeds into your understanding of what their world is like.


HERZING: But, usually, when I'm down there, I'm, like, trying to follow behavior and making sure my camera's on.

RAZ: Right.

HERZING: It's actually mostly work, really.

RAZ: Right.

Denise Herzing has been doing that work every summer with the same group of dolphins in the Bahamas...

HERZING: Let's see. I just calculated it recently.

RAZ: ...For 35 years.

HERZING: Yeah, like, 3,000 encounters in the water with the dolphins, and then each of those encounters is about 20 minutes long, so...

RAZ: Over 1,000 hours of footage and observational data.

HERZING: So, yeah, it's a lot of data, certainly, for dolphins.

RAZ: And the point of all that data, of all that work, is to help Denise answer one question.


HERZING: Do they have a language? And if so, what are they talking about?

RAZ: Here's Denise Herzing on the TED stage.


HERZING: Now, I'm interested in dolphins because of their large brains, and we know they use some of that brainpower for just living complicated lives. But what do we really know about dolphin intelligence? Well, we know a few things. We know that their brain-to-body ratio, which is a physical measure of intelligence, is second only to humans. Cognitively, they can understand artificially created languages, and they pass self-awareness tests in mirrors. And in some parts of the world, they use tools like sponges to hunt fish.

Now, dolphins are natural acousticians. They make sounds 10 times as high and hear sounds 10 times as high as we do, but they have other communication signals they use. They have good vision, so they use body postures to communicate. They have taste not smell, and they have touch. And sound can actually be felt in the water because the acoustic impedance of tissue in water is about the same, so dolphins can buzz and tickle each other at a distance. So decades ago - not years ago - I set out to find a place in the world where I could observe dolphins underwater to try to crack the code of their communication system.


RAZ: Well, first of all, how do dolphins communicate to each other?

HERZING: Well, you know, we can actually hear a fair amount. Their whistles are fairly audible to us.


HERZING: They have clicks.


HERZING: They have burst pulses, which are also...


HERZING: ...Packets of clicks.


HERZING: So they have all these different cues, and they, you know, use body postures in combination with sounds that will basically communicate certain things to each other.

RAZ: You know, this is total anthropomorphization (ph), but, like, when you think of - like, when you see a dolphin animated or drawn in a kid's book, they seem to be smiling. But I - we should not interpolate that that means that they're happy all the time, right?

HERZING: Oh, definitely not, yeah. That is just a physical thing that they have going, yeah.

RAZ: How do you respond when other researchers say - you know, push back and say, hey, like, let's not do that; let's not anthropomorphize these creatures?

HERZING: You know, you just keep doing your work, I think. I don't even think it's a discussion anymore, honestly. Most of us that work with social mammals, I think, have kind of moved beyond that and just say, well, it's a valuable tool for thinking about how they might think. And let's do the work.

RAZ: Is it even weird to talk about dolphin language? Or is it - should we be talking about dolphin communication?

HERZING: Yeah, we don't really usually talk about language because we don't know if they have it yet. But thinking out of the box is - you know, it's like intelligence. You know, are there different kinds and types of intelligence? Are there different kinds and types of language? I mean, we know there's tons of kinds of language with humans, right?

RAZ: Yeah.

HERZING: But one of the big things about language is that you can communicate about a different time and space, right? Are they talking about the food they're chasing? Are they eating? Or are they talking about - hey, let's go to the reef in a couple days and meet up with this other group? You know, we don't know. And that's where, you know, anthropomorphism can be a tool for thinking about how animals might be thinking.

RAZ: Which brings us back to the Bahamas and a pivotal moment in Denise Herzing's years of work with Atlantic spotted dolphins there. It happened one summer...

HERZING: I guess in the mid-'90s...

RAZ: The dolphins did something they had never done with Denise before.

HERZING: We just started noticing the dolphins would just start doing things - and this is completely wild, right? But we knew the individuals, and they would start doing things like mimicking our body posture; in some cases, mimicking, like, the rhythm of our sounds in the water if we were doing anything vocally. And we just kind of thought, man, wouldn't it be cool to see if we empowered them to communicate back to us?

RAZ: And the key to unlocking that communication turned out to be play. Dolphins, just like humans, love to play games, mostly with toys - a piece of rope, a bit of seaweed, anything they can pull around in the water.

HERZING: Correct.

RAZ: So what kind of games do they like to play?

HERZING: Well, it's mostly called keep-away. That is, if they get the toy, then the idea is - they like to be chased. They like to let you get almost close enough to grab the toy, but then they speed off. And that's the game. That's how they play with each other, actually.

RAZ: The only question was how to use that play to crack the code - the code that would unlock the meaning behind the dolphins' noises.


HERZING: Now, one way to crack the code is to interpret these signals and figure out what they mean. But it's a difficult job, and we actually don't have a Rosetta stone yet. But a second way to crack the code is to develop some technology, an interface to do two-way communication. And that's what we've been trying to do in the Bahamas and in real time. So we built a portable keyboard that we'd push through the water, and we labeled four objects they'd like to play with - the scarf, rope, Sargassum and also had a bow ride, which is a fun activity for a dolphin.


HERZING: And that's the scarf whistle, and these are artificially created whistles. They're outside the dolphins' normal repertoire, but they're easily mimicked by the dolphins. And I spent four years with my colleagues Adam Pack and Fabienne Delfour working out in the field with this keyboard, using it with each other to do requests for toys while the dolphins were watching. And the dolphins could get in on the game. They could point at the visual object, or they could mimic the whistle.


RAZ: Another way to imagine this experiment, Denise says, is think of how you try to teach words to a baby.

HERZING: And you're trying to get them to understand the word milk. So you have a glass of milk, and you're going...


HERZING: Here's some milk. Or, do you want the milk? Or would you like some milk?

So we're not really teaching them commands. We're exposing them to the communication system with the hopes that they'll learn to use it to communicate back to us what they want.

RAZ: OK, so an underwater keyboard - four buttons, each with a different whistle sound for a different toy.

HERZING: So the dolphins were actually doing really cool things like - we would play a computer whistle, say, like (imitating dolphin whistle) for Sargassum, which is a piece of seaweed they play with. (Imitating dolphin whistle). And the dolphins would immediately tag on another whistle to the end of the computer whistle.

RAZ: So yeah. The answer to the question - do dolphins have a language? - is maybe, kind of. They certainly have a desire to communicate. So now Denise and her fellow researchers are teaming up with a group of computer scientists to use machine learning to try to parse and analyze those extra whistles and figure out what they might mean.

HERZING: So that's actually what we're going to be doing late this summer.

RAZ: Well, like, when an anthropologist stumbles on a discovery and some ancient tablet - right? - they can spend a lifetime trying to decipher it and then figure out what the symbols meant. But that's a physical thing that you can look at, right? I mean...


RAZ: ...You can imagine that this is a version of that. But with increasing computing power, I mean, you could potentially imagine a scenario where the hieroglyphics, so to speak, in dolphin communication could be decoded.

HERZING: Yeah, well, that's what we're working on. I mean, remember, you know, hieroglyphs is a written language...

RAZ: Sure.

HERZING: ...And that's something that dolphins will never have. At least I can't imagine it. But, you know, maybe they have an oral history that they produce like humans did - right? - before we even had writing. But yeah, I have no doubt that machine learning's really going to help us parse out the information.

RAZ: So if you or I went to Europe 20 years ago, we would have a little phrase book, and that might be all we had. And now you can just speak into Google Translate, and then it will - and then you can play it, and it will play it for someone. You can imagine, in 20 or 30 years from now, traveling to Asia and speaking in real time and having, like, a headset around your head that was a simultaneous translator, an AI translator that would enable you to have a really serious and deep conversation with somebody in their language.

HERZING: Yeah, sure. I mean, that's probably coming in shorter than 20 years, I would bet.

RAZ: Yeah. Right.

HERZING: And, you know, what's really interesting is if you look at how other animals communicate with each other - and they do, right? We're way behind the times because we don't have to communicate with animals, right? But there are a lot of birds that really know the alarm calls of their neighboring species because it helps them survive. So nature already communicates in many ways just without us in the loop. So we probably should get in the loop.


RAZ: That's Denise Herzing. She's the research director of the Wild Dolphin Project. Her full talk is at

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