Short Wave - Extracting Brains ... For Science

Episode Date: February 25, 2025

A year and a half ago, neuroscientist Kamilla Souza got the call she'd been waiting for: A baby humpback whale had died just offshore. She wanted its brain. That's because scientists know little about the brains of whales and dolphins off the Central and South American coasts. Studying them, like Kamilla is doing, can teach scientists about the inner workings of these animals — about their behavior and how they're adapted to living underwater. So, she has to race against time to save the brains. The heat in this area of Brazil accelerates decomposition. Minutes matter. This episode was reported by Ari Daniel. Read more of Ari's reporting.Curious about other biology research happening around the world? Let us know by emailing [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 to tell you about a treasure hunt. Though not the treasure you may be expecting. Yeah, almost certainly not. Ari, Daniel, you're a science reporter, and you're bringing us the story which took place like a year and a half ago, right? Yes.

Okay, so set the scene for us. Right. Okay, so that's when this Brazilian neuroscientist I met named Camila Soza gets the call she's been waiting for. A baby humpback whale is a drift just offshore in the waters off southeastern Brazil. It's just dying. And she wants its brain. It's like Alice in Wonderland. Give me the head.

I went from like sad to like now I'm just surprised. She wants the brain? What? I know. I know. But there are some really important reasons to study the brains of whales and dolphins. And I will get to that. Okay.

I trust you. Great, I'm glad. But first, let me finish telling you what happened to that baby humpback. Okay, deal. By the time Camilla and her colleagues arrive on the scene by boat, the whale has washed ashore on a tiny island. And they have a problem. They can only get so close without running or ground.

You look at the situation and you say, okay, I need it. I'll get this one no matter what. And then I didn't have time to think. You just have to go. So Camila grabs her scalpel and saw, and swims to shore. She swims? She swims.

She really wants that brain. Wow. She gets to the beach and she's totally soaked. But she whips out her tools and after a couple of hours she manages to extract the fresh, intact brain

from the recently deceased whale. Whoa. She is elated. It was the first extraction of a whale brain here in Brazil. Camila brings it back to her lab where it joins the ranks of what she says

has become the largest collection of whale and dolphin brains in all of Latin America. So today on the show, why this early career neuroscientist is going to all the trouble of getting her hands on so many whale and dolphin brains. And how she's recruiting a new generation of Brazilian researchers to roll up their sleeves to join her. I'm Regina Barber. I'm R.A. Daniel. And you're listening to Shortwave, the science podcast from NPR. Okay, all right, now that we're back. Clear something up for me. Like, does Camilla have to swim to shore every time she wants a brain?

No. Usually the brains come to her at the Orca Institute. That was where I met up with Camilla in mid-December. She was bedecked in marine mammal jewelry, dolphin earrings, a whale bracelet. You get the idea. That's adorable. Because people know that I like dolphins. The Orca Institute is a conservation organization outside of Victoria in southeastern Brazil, where, before recently, taking time off, for a short fellowship at Oxford, Camila worked as the scientific director. The morning I was there, a van had just pulled in. So there's a van with a special delivery? I would say yes.

It's a dolphin that stranded in a beach. The Orca Institute tends to any marine mammal that strands itself along its section of the coast and either rehabilitates and returns it to the water if it's alive, or, as is the case with this recently deceased Guyana Dolphi, being hoisted into the air, brings it back to their facility to figure out what might have gone wrong. We are going to analyze all the organs of this animal and to investigate the cause of the death. With an eye towards preventing similar deaths in the future. Ah, okay. I mean, when these dolphins and marine mammals get stranded,

do the scientists know why that happens, Ari? Well, one of the vets told me that often the animals become entangled with fishing gear, or they suspect loud underwater noises might cause them. the animals to surface too quickly. The staff here rotates through a daily on-call schedule because an animal can strand pretty much any time. But for Camilla, these animals are a means to an end. Those brains, right?

Yes. I think about the brain. You think about the brain. It's something she's been fascinated by ever since she was little. And here's why she thinks brains are so important to study. See, I knew it. I knew I could trust you. We're there now.

True to my word. Camila says there's actually very little known about the brains of whales and dolphins living in the waters off central and South America. But mapping how those brains are wired up can teach scientists about the inner workings of these animals, about their behavior and how they're adapted to living underwater. Plus, dolphins have Alzheimer's, encephalitis, meningitis. So it's an opportunity to understand diseases that can also affect. to humans. Really, Alzheimer's? That's fascinating. It's still early days of confirming the disease, Regina. But yes, there have been signs of the hallmarks of Alzheimer's and certain dolphins. So for all these reasons, Camilla's intent on gathering and studying the brains of cetaceans.

Cetations? Is that a word for whales and dolphins that I don't know? Yes, yes. Okay. And now you know it. Now I do. You're teaching me so much today. I do what I can. So back to Camila. She's collecting and gathering cations. from this part of the world and is making real progress. She points to the 200-pound suspended Guyana dolphin, a coastal species that lives in the Atlantic off Central and South America. We have a lot of studies about the behavior of this animal, but studies about the brain, we didn't have.

So we published the first brain description for this species. Wow. Okay. So how do they, like, study these brains? Like, what can they learn from a brain that's, like, no longer all? for lack of a better word. Yeah, well, a few years back, Camilla and her colleagues used an MRI to describe the neuroanatomy and internal brain structure of a Guyana dolphin that washed ashore west of Rio de Janeiro, which was a real achievement. Because these brains are really hard to get, right? Bingo. And that becomes super clear when Camilla takes me to the necropsy room.

Oh, my goodness. What is that sound? That, Gina, is the sound of knives. being sharpened. The vets are dissecting another dolphin, a female, that recently stranded, and a parade of organs appears on the table before me to be measured and photographed.

Oh, my God. And you saw this? I did. I saw the heart. I saw a kidney. Wow. The uterus. Camila brings me around to the head. Oh, no. So here we have the skull. There is no brain. Okay, it's liquefied. Yeah, exactly. And that's

the point. We need to have a fresh Carcas. Okay, so like fresh as in the brain hasn't turned to goo, like so they can still study it. Right, and that's a challenge in a big country like Brazil. The heat accelerates decomposition, so minutes matter, which means that sometimes Soza has to extract the brain from an animal right on the beach and put it in preservative. This all makes sense now, like why she had to like swim to that baby humpback? Precisely. We have to do with people, animals, the weather. Sometimes. Sometimes it's raining.

But Camilla's relentless, Daniela Tellis told me. Daniela is one of the Orca Institute vets. She can find the treasure that it's hidden inside all of this flesh and carcass and smell and all. She finds the brain and all and studies it. And it's amazing. So whenever the conditions do conspire in her favor, Camilla gets herself another brain. I mean, I love the way they talk about these brains. But did you actually get a see one?

I did. What do you think I've been building? up to, Gina. I don't know. I'm in suspense. I follow her next door to her office. This is definitely a refrigerator filled with brains. In this fridge alone,

she's got a brain from a pygmy sperm whale, various dolphin species, and more. She lifts a brain out of the largest plastic container. It's from that baby humpback she swam ashore to dissect, and it's twice the size of a human brain. So this brain is huge. I need the two hands to hold this brain. Wow.

Wow. There before me is arguably the convoluted essence of a humpback whale, the thing that lets it swim and sing and so much more. All right. I really like this story. It's fascinating, but it's also kind of gross. And like Camilla, she's so cool. I mean, she's early in her career.

Like, what is she planning to do next? Like, where is she going to go? Well, Camila says she'd, likely be able to work abroad. She's got all this expertise. She has access to these understudied species. She's even done stints abroad. But there's only one place she wants to be. And that's Brazil. I'm here because I want. I want to do this kind of research here. I want to bring this knowledge to Brazil. I want to inspire Brazilian people to do something new, to do something special. People like Hittor Min Singh, a PhD student in the lab, who

developing a fancy tool to model the cetacean brain in 3D. He too wants to contribute to the field from Brazil. We don't have to always rely on other countries. We can actually do it on our own and show the world that we can actually do good science. Being able to be a scientist in Brazil, that's very different. It feels like part of me. Oh.

My last stop on my trip is a nearby stretch of beach. Camila looks out at the ocean and she considers the trajectory that brought her to this moment. I think that I did the right thing because I'm super happy with my work and with the things that I'm doing for my country and for me as I researcher. Camila says that little girl she used to be

would be happy. Oh, I just love the way she talks about it work. It's so joy-filled. It sounds like it's healing her inner child. Yeah. Ari, thank you so much for this lovely story about cetacean brains, right? You got it, cetacean brains. Of course, my pleasure, Gina.

Thank you. New word. For all you listening, if you liked this episode, make sure you never miss a new one by following us on whichever podcasting platform you're listening from. And if you have a science question, you'd like us to investigate, send us an email at Shortwave at NPR.org. This episode was produced by Hannah Chin and edited by showrunner Rebecca Ramirez.

Tyler Jones checked the facts. Beth Donovan is our senior director and Colin Campbell is our senior vice president of podcasting strategy. I'm Regina Barber. Thank you for listening to Shortwave, the science podcast from NPR.