Mystery of whale song unraveled by scientists, study says - CNN

Marina: Welcome to Deep Voices — I'm Marina, a marine biologist and ocean storyteller, and this is the show where we dive beneath the surface to explore the minds, voices, and lives of whales and dolphins. So glad you're here with me today. Marina: Before we get into it, a huge thank you to our sponsors: Ada, who helps businesses integrate A I into their workflows in ways that actually make sense; Ago Consulting — pronounced "Ahh-Go" — silicon development experts working across everything from A I to SoC; and Zen Semiconductor, an umbrella company with an incredible portfolio spanning the silicon industry. These folks make Deep Voices possible, and I'm genuinely grateful. Marina: Today we have got a lot to talk about. Scientists think they've cracked open one of the ocean's oldest mysteries — the structure of whale song. A humpback mother stayed beside her stillborn calf for days in a vigil that left researchers speechless. And we're going to explore what A I might mean for our ability to finally understand what whales are actually saying — and whether those same tools might one day help us talk to something even more alien. Let's go deep. Marina: Okay, thread one — Voices of the Deep. And I want to start with something that honestly made me stop in my tracks when I read it this week. Scientists have made a significant breakthrough in understanding the structure of humpback whale song — and what they found is extraordinary. Humpback songs aren't random sequences of sound. They're not just beautiful noise. They appear to be structured according to rules that look remarkably similar to the rules underlying human language. Marina: Now, let me paint you a picture of what humpback song actually sounds like if you've never heard it. Imagine you're underwater — total blue, shafts of light filtering down — and then it starts. This low, resonant moan that shifts and slides, rising into creaks and whistles and then dropping into something almost like a groan. It goes on for hours. It travels for hundreds of miles. And every male humpback in an ocean basin is essentially singing the same song — but the song changes, season by season, year by year, evolving across the population in real time. Marina: Researchers publishing in the journal Science found that humpback songs contain what linguists call "hierarchical structure." That means the songs aren't just sequences of notes — they're organized into phrases, phrases into themes, themes into the full song. Sound familiar? That's exactly how human language works. Words build into sentences, sentences into paragraphs. There's a grammar to it. A logic. Marina: And here's what really gets me. The study used information theory — the same mathematical framework Claude Shannon developed to understand human communication — and found that whale song follows similar statistical patterns to human speech. The sounds are not random. They carry information in a structured, layered way. Now, that does not mean we know what the information *is* — not yet — but it means humpbacks have evolved a system of vocal organization that, structurally speaking, rivals our own. Marina: The researchers also found something called "non-random silence." Pauses in whale song are not just rests — they appear to be meaningful, placed in ways that suggest they play a role in the structure of the message. Silence as syntax. I find that deeply beautiful. The spaces between the notes matter as much as the notes themselves. Marina: Male humpbacks are the singers. They sing during breeding season, and the leading hypothesis is that song plays a role in attracting females and competing with other males. But here's the thing — if it were just about broadcasting "I exist, I am fit, come find me," you probably don't need hierarchical grammatical structure to do that. A simple repeated call would do. The complexity of the song — the layering, the evolution, the shared cultural transmission across thousands of miles of ocean — suggests something richer is going on. We just don't know what yet. Marina: And that's the magic and the frustration of this science. Every answer opens three new questions. But the fact that we can now say, with mathematical rigor, that humpback song is structured like human language — that's a genuine landmark. These are not just beautiful creatures. They are complex communicators. And we are only just beginning to listen properly. Marina: Thread two — Culture and Decoding. So we've just talked about the *structure* of whale communication. Now let's talk about what happens when humans try to actually decode it. And this is where things get really exciting — and really humbling. Marina: There's a piece out this week from Canadian Geographic that I loved — it asks a beautifully simple question: can we speak with whales? Not metaphorically. Literally. And the scientists working on this are some of the most interesting people in biology right now. Because they're not just asking "what do whales sound like?" They're asking "what are whales saying?" And increasingly, they're using A I to try to find out. Marina: The most prominent project in this space right now is Project CETI — that stands for Cetacean Translation Initiative. They're focused on sperm whales, specifically the click-based communication system called codas. Sperm whales produce these rapid sequences of clicks — ta-ta-ta-TA-ta — and researchers have documented that different whale clans use different coda repertoires. It's like a dialect. A cultural signature. A whale born into one clan learns one set of codas; a whale in a different clan, separated by hundreds of miles of ocean, speaks a different one. Marina: Project CETI is deploying hydrophones, underwater drones, biologging tags, and cameras to record millions of sperm whale vocalizations in the waters around Dominica. Their goal is to feed all of that data into machine learning models — the same kind of large language models that underpin tools like the A I systems used in everyday life today — and look for patterns. Look for structure. Look for meaning. Marina: Now, The Atlantic ran a piece this week that connects this beautifully to something even bigger. The argument is this: if we develop the tools to decode whale communication — to take an alien acoustic system and find the meaning inside it — those same tools might help us decode genuinely alien communication, if we ever encounter it. The logic is elegant. Whales and humans share a common ancestor from hundreds of millions of years ago. We diverged so long ago, and evolved such different bodies and lives and environments, that in some ways communicating with a whale *is* communicating with something alien. If A I can crack that code, we're building the translation engine for the unknown. Marina: But here's what I want to sit with for a moment. Because I think it's easy to get dazzled by the technology and miss the deeper story. Sperm whale clans don't just share dialects — they share culture. They share knowledge. Grandmother sperm whales lead their families to feeding grounds they've known for decades. Young whales learn which sounds mean what. There are documented cases of sperm whales apparently coordinating defensive formations when threatened — the "marguerite formation," where they cluster nose-to-nose with calves in the center, tails pointing outward. That's not instinct. That's a learned, culturally transmitted strategy. Marina: So when we talk about decoding whale language, we're not just deciphering a code — we're trying to read the accumulated cultural knowledge of a society that's been around for millions of years. And A I gives us the first real tool with any hope of doing that at scale. Not because A I is magic — it isn't — but because the sheer volume of data you need to find meaningful patterns in whale communication is beyond what human researchers can process alone. You need a system that can listen to millions of codas and say: here's a pattern. Here's a structure. Here's a signal in the noise. Marina: We're not there yet. I want to be clear about that — we have not translated whale language. But we are closer than we have ever been. And I find that genuinely thrilling. To think that within my lifetime, we might have our first real glimpse into what a sperm whale is actually saying to her family — that feels like one of the most important things humanity could ever do. Marina: Thread three — a Cetacean and People story. And this one hit me right in the heart. I want to talk about grief. Because this week, researchers reported something that I think deserves a moment of real stillness. Marina: Off the Gold Coast of Australia, a humpback whale mother was observed staying beside her calf — a calf believed to have been stillborn — for hours, and possibly days. She didn't leave. She stayed close. She maintained eye contact with the calf. She nudged it, and positioned herself near it, in ways that researchers described as resembling caregiving and nurturing behavior. She was, as far as the scientists watching could tell, refusing to leave her baby. Marina: Now, I want to be careful here, because science asks us to be careful. We can't know with certainty what a whale is experiencing internally. We can't put words to it with total confidence. But what I can tell you is what researchers observed: a mother, exhibiting prolonged close association with her dead calf, in behaviors consistent with maternal bonding and caregiving — behaviors that in living calves serve to protect and nurture. She was doing the same things for a calf that could no longer respond. Marina: This is not the first time something like this has been documented in cetaceans. Bottlenose dolphin mothers have been observed carrying deceased calves at the surface for days. Orca mothers have done the same. There's a famous, heartbreaking case of an orca named Tahlequah — she's from the endangered Southern Resident killer whale population — who carried her dead newborn calf for seventeen days and over a thousand miles of ocean in 2018. Seventeen days. That story made international headlines, and it should have. Marina: What all of these observations point to is something scientists are increasingly willing to say out loud: cetaceans grieve. They have emotional responses to the death of individuals they are bonded to. And when you understand the depth of cetacean social bonds — the fact that humpback mothers nurse their calves for nearly a year, that orca calves stay with their mothers for life, that sperm whale families are multigenerational, matrilineal societies — the grief makes sense. Of course it does. Marina: The researchers who documented the Australian humpback mother say this observation offers new insight into maternal attachment and emotional complexity in humpback whales. What strikes me is the phrase "emotional complexity." Because it's one thing to say an animal has emotions — it's another to say those emotions are *complex*. Layered. Lasting. Not just a reflexive response but something sustained, something that shapes behavior over time. Marina: There's a human dimension to this story too, and I think it's worth naming. The people who observed this whale — the researchers and likely some members of the public nearby — were watching something extraordinarily intimate. A private moment of loss playing out in a very public ocean. And I think our instinct to witness it, to be moved by it, to report on it and talk about it — that instinct is right. Because when we recognize grief in another being, we are recognizing kinship. We are acknowledging that we are not the only creatures on this planet who love, who bond, who lose. Marina: That mother whale off the Gold Coast didn't know anyone was watching. She wasn't performing. She was just — there. With her calf. And I think that's one of the most profound things I've encountered this week. The ocean is full of stories like this, playing out beneath the surface, with or without us. Our job is to pay attention. Marina: And that brings me to the close of today's episode. I keep coming back to this image — a humpback mother in the blue water, and scientists on the surface measuring the structure of song, and engineers building A I systems to decode clicks, and researchers staying up late poring over recordings looking for meaning. All of us, in our different ways, trying to reach across a tremendous gulf of biology and evolution and say: we hear you. We want to understand. Marina: The ocean has been speaking for millions of years. We are only just beginning to develop the ears to listen. And I believe that when we finally understand what's being said down there, it will change us — the way we see intelligence, the way we define communication, the way we understand what it means to be a mind in this world. Marina: Deep Voices, brought to you by Ada, Ago Consulting, and Zen Semiconductor. Thank you to each of them for supporting this show and the curiosity that drives it. Marina: If today's stories moved you — and I hope they did — please subscribe to Deep Voices wherever you listen to podcasts, and share it with someone who loves the ocean, or who needs to. And check the link in show notes for more on all of today's stories — the humpback song research, Project CETI, the story of the grieving mother, all of it. Stay curious, stay kind to this planet, and I'll meet you back here next time. Deep into the blue.