What we — and AI — can learn from nature's intelligence

Artificial intelligence is powerful, but what about natural intelligence? This hour, TED speakers explore the intrinsic genius in animal language, insect behavior, plant anatomy and our immune system. Guests include neuroscientist Greg Gage, computational neuroscientist Frances Chance, social psychoneuroimmunologist Keely Muscatell and environmental researcher Karen Bakker. We want to dedicate this episode to Bakker who passed away in August 2023, only a few months after giving her TED Talk. Her research and legacy continue to inspire. Original broadcast date: March 8, 2024 TED Radio Hour+ subscribers now get access to bonus episodes, with more ideas from TED speakers and a behind the scenes look with our producers. A Plus subscription also lets you listen to regular episodes (like this one!) without sponsors. Sign-up at plus.npr.org/ted http://plus.npr.org/ted. See pcm.adswizz.com https://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 https://www.npr.org/about-npr/179878450/privacy-policy

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Manoush Zomorodi?

  This episode's sponsor is HubSpot, which offers the following message: What if instead of updating your CRM, your CRM updated you? HubSpot's self-updating CRM keeps your customer context current so you can win more deals. Learn more at hubspot.com. This is the TED Radio Hour. Each week, groundbreaking TED Talks. Our job now is to dream big. Delivered at TED conferences. To bring about the future we want to see. Around the world. To understand who we are. From those talks, we bring you speakers and ideas that will surprise you.

• 0:37Speaker 01

  You just don't know what you're gonna find.

• 0:39Manoush Zomorodi?

  Challenge you.

• 0:40Speaker 01

  We truly have to ask ourselves, like, why is it noteworthy?

• 0:42Manoush Zomorodi?

  And even change you. I literally feel like I'm a different person. Yes. Do you feel that way? Ideas worth spreading from TED and NPR.

• 0:55Manoush Zomorodi?

  I'm Manoush Zomorodi, and on the show today, natural intelligence. And we're going to kick things off by going back in time to the 1750s and a marshy, swampy, subtropical wetland in North Carolina, where a man named Arthur Dobbs lived.

• 1:18Speaker 02

  Yeah, no, I like Arthur Dobbs.

• 1:21Manoush Zomorodi?

  This is our tour guide, Greg Gage.

• 1:24Speaker 02

  He was the governor of North Carolina. This is back in the 1750s, still under British rule.

• 1:31Manoush Zomorodi?

  And Arthur, he says, was a curious man, a bit of a gentleman scientist. So when Arthur started to hear a rumor about a very unusual plant growing not that far away, he decided to go check it out.

• 1:46Speaker 02

  And he heard these stories about this plant. He says, well, I'm the governor of this land. I should go investigate.

• 1:55Speaker 02

  He went out to the swamps. And so there's a little, small area. I think it's about six square miles.

• 2:02Speaker 02

  And then there, low to the ground, are these little tiny plants. And that if you watch them long enough, a bug will eventually fall into its little or walk across its little leaves and it snap shuts and it eats this bug. And so, of course, he's pretty fascinated by this.

• 2:18Manoush Zomorodi?

  Understandable because, well, no Europeans had ever documented a plant like this before. So.

• 2:25Speaker 02

  He does what scientists do at the time. They take out a letter and they write to their colleagues in Europe.

• 2:33Speaker 03

  The great wonder of the vegetable kingdom is a very curious, unknown species of sensitive.

• 2:39Manoush Zomorodi?

  He writes, "It's a dwarf plant. Leaves are like a narrow segment of a sphere consisting of two parts, like the cap of a spring purse."

• 2:49Speaker 03

  Upon anything touching the leaves or falling between them, they instantly close like a spring trap. To this surprising plant, I've given the name of flytrap sensitive.

• 3:01Manoush Zomorodi?

  The flytrap sensitive, or as we call it today, the Venus flytrap. The news of this remarkable animal-eating plant took off across Europe. And 100 years later, Charles Darwin would write an entire book called Insectivorous Plants.

• 3:17Speaker 04

  Eventually, the great Charles Darwin got to study this plant. And this plant absolutely blew him away. He called it the most wonderful plant in the world.

• 3:25Manoush Zomorodi?

  Here's Greg Gage on the TED stage.

• 3:27Speaker 04

  This is a plant that was an evolutionary wonder. This is a plant that moves quickly, which is rare, and is a plant that's carnivorous, which is also rare. And it's in the same plant. But I'm here today to tell you that's not even the coolest thing about this plant. The coolest thing is that the plant can count.

• 3:45Manoush Zomorodi?

  So let's pause for a moment. Greg Gage is not just an amateur flytrap historian. He is actually a neuroscientist and educator. And on the TED stage, he conducted a live science experiment.

• 3:58Speaker 02

  So I'm going to pretend to be a fly right now.

• 4:00Manoush Zomorodi?

  Surrounded by monitors, microscopes, and of course, plants.

• 4:04Speaker 02

  And here's my Venus flytrap. And inside the leaf, you're going to notice that there are three little hairs here. And those are trigger hairs. And so when a fly lands, I'm going to touch one of the hairs right now.

• 4:14Manoush Zomorodi?

  Attached to the flytrap, EKG sensors, measuring any electrical signals generated by the plant.

• 4:21Speaker 02

  Ready? One, two, three.

• 4:23Manoush Zomorodi?

  And there, the monitor lit up as Greg grazed the hairs inside the flytrap.

• 4:29Speaker 04

  What do we get? We get a beautiful action potential. However, the flytrap doesn't close.

• 4:34Manoush Zomorodi?

  That's because it's waiting to see if it gets touched again within 20 seconds or so. Venus flytraps don't want to be hasty for several reasons.

• 4:45Speaker 04

  Number one is that it takes a long time to open the traps back up, you know, about, you know, 24 to 48 hours if there's no fly inside of it. And so it takes a lot of energy. And number two, it doesn't need to eat that many flies throughout the year. It only needs to need a handful. It gets most of its energy from the sun. It's just trying to replace some nutrients in the ground with the flies. And the third thing is, it only opens, uh, then closes the traps a handful of times until that trap dies. So therefore, it wants to make really darn sure that there's a meal inside of it before this flytrap snaps shut. So how does it do that? It counts the number of seconds between successive touching of those hairs. I'm going to touch the Venus flytrap again. I've been talking for more

• 5:27Speaker 04

  than 20 seconds. And then if I'm a fly moving around, I'm going to be touching the leaf a few times. I'm going to go and brush it a few times. And immediately, the flytrap closes. So here, we're seeing the flytrap actually doing a computation.

• 5:44Manoush Zomorodi?

  I mean, that sounds like this plant is pretty smart.

• 5:49Speaker 02

  Yeah, it's, uh, well, I mean, it definitely is competing. I always think that plants are, are kind of cool because, you know, humans, if, if there's a rough situation, we can just run away, right? We can just kind of like get out of Dodge. But these plants, they're stuck there. They're in the ground, right? And so they're got, they have got nothing to do except for try and feed themselves. They come up with very incredible ways of doing that.

• 6:12Manoush Zomorodi?

  We hear a lot about the powers of artificial intelligence. But all around us, nature continues to find extraordinary ways to survive and communicate that we are still just beginning to understand. So today on the show, natural intelligence. New findings about the brilliance of dragonflies, our immune system, and whales, and how they are influencing human behavior.

• 6:39Manoush Zomorodi?

  First, though, back to Greg Gage. He brought another surprisingly sensitive plant onto the TED stage.

• 6:46Speaker 04

  To the mimosa, not the drink, but the mimosa purica.

• 6:51Manoush Zomorodi?

  Greg, during your stage experiment, you also had this other plant that kind of looks like a fern, and it's called a mimosa.

• 6:59Speaker 04

  And this is a plant that's found in Central America and South America, and it has behaviors.

• 7:03Manoush Zomorodi?

  And you just lightly touch the leaves, and it kind of like wilted away from you.

• 7:09Speaker 04

  If I tap the leaf, the entire branch seems to fall down.

• 7:12Manoush Zomorodi?

  And my dad actually had a mimosa plant when I was a kid. And I was fascinated by this response. Like, I would touch it, and it would pull away from me. Like, get off me, you know?

• 7:21Speaker 02

  Yes, it's actually very, very similar to humans, right? So there's like a touch receptor, just like we do in our, in our skin. And when we press out on something, we feel it because an electrical impulse is being sent back up to our brains, and we interpret that impulse as the feeling of touch. Inside of this leaf, very similar cells are within there that will send an electrical current. Only this time, instead of using muscles, it again uses water, flushes the water out, and makes the plant move.

• 7:51Manoush Zomorodi?

  But why? Is it always about survival?

• 7:55Speaker 02

  I suspect so. And it's funny, because with the mimosa, there's a couple of theories of why. If an animal brushes past, it doesn't look as... I'm looking at mine right now. They don't look very tasty, right? Maybe I would eat a different plant if I saw that one. Or maybe it kind of freaks out some insects that would want to land on it. So that's a learning mechanism they can do, but that's kind of boring compared to some other experiments that have been done. Experiments where you can take a pea pod, and you let it grow in the dark. You have like a little tube that goes up, and it kind of goes like a Y. It's called a bifurcated tube. And if you shine a light in one of the tubes, say on the right side, and you blow a fan on the other one. You can do this protocol where you kind of,

• 8:39Speaker 02

  you blow the fan on the left, and then you shine the light on the right. And then the next day, you blow the fan on the right, and you shine the light on the left. Each day is kind of growing up this tube, trying to get to the top of it, right? And then on the experiment day, right, we're about to make a decision. You flip it again, but you only blow the fan. And then you ask the question, which way will the plant grow? Will it grow where it last saw the light, which makes sense, right? Or did it figure out the relationship between the fan and the light and grow to where the light would have been if it's going to come on soon, right? You get a majority of the plants that kind of figure it out. They kind of figure out that they have to go in the other direction and go away from

• 9:22Speaker 02

  where it lasts on the light, but where the fan was indicating where we go. To me, that's, that's kind of flexible. And then that's starting to show some decisions, right? That's starting to show a little bit of intelligence. So it's the ones that made it are the ones that it can sort of live on to, to tell the story, right? And so then those genes get inherited and move forward.

• 9:43Manoush Zomorodi?

  So we have covered plants, which seem like a more simple life form than, say, mammals, yet kind of display some very seriously smart behavior. But you are also really interested in, it seems strange to say this, but you're really excited about slime mold, which is not a plant, but...

• 10:04Speaker 02

  No, but a mold is a cell, right? A slime mold is a single cell. They, they kind of sit in a Petri dish and you feed them, you feed them little oats and they kind of wrap around it and they kind of suck up the nutrients and they kind of can go dormant for many, many years and they can come back alive again.

• 10:18Manoush Zomorodi?

  Wow.

• 10:19Speaker 02

  Yeah, they're absolutely fascinating, but they're...

• 10:22Manoush Zomorodi?

  You can see them though? Even though they're single cells?

• 10:25Speaker 02

  They could be, yeah, they could be, a single cell could be like, you know, a meter long. They're, they could be big, so they're macro. And so we, we were doing an experiment, one of the experiments we did was we put a piece of food in there, we watched how often would it go towards the food? And not surprisingly, it goes towards the food a lot, right? But slime molds are kind of, they don't want to be dried out, so they don't like sunlight. And so if you shine a light there, you know, then they will shy away from it. They'll try to go around it, but they won't go through, they try not to go through the light. That would make sense if it was an animal. You're like, okay, well, their eyes are seeing it. The eyes are sending the message back to the brain and the brains are telling the muscles which way to go. But then you realize, wait a minute, there's no brain, right? There's no, there's just, it's just cells, right? So they have these sensors on the outside of the cell that's sending back information,

• 11:09Speaker 02

  but that information's being processed inside the cell itself.

• 11:14Speaker 02

  And so I think there's a lot to be said about the about the cell. I mean, the cell is basically a little computer. It's got a little Turing machine inside of it, and it has goals, right? It tries to do things. And so it has a lot of, a lot of things in its resources to be able to do.

• 11:32Manoush Zomorodi?

  I recently went to a lecture about the crows that are the only birds that we know that use or fashion and then use tools.

• 11:40Speaker 02

  Oh, corvids, yeah.

• 11:41Manoush Zomorodi?

  They're amazing. And just every so often, you hear this incredible story that shouldn't blow our minds, but does, about how the natural world is so incredibly smart. And I guess I'm wondering, you know, should it, should it expand our definition of intelligence? How, in simple terms, how do we define what intelligence is?

• 12:06Speaker 02

  Yeah, I think the simplest way, given what you've got, right? You've got to figure out how to be able to get to what you want, right? And so that's kind of my, kind of the back of the envelope sketch of intelligence, is being able to get to what you want, given what you have. And that's what intelligent things do. You look at a dog trying to get through a door, it'll kind of go check the other door. It's doing, it's trying to figure out what it needs to do. And so you could look at these, these plants, you know, in the, in the case of these plants that are trying to find the light, they're doing, they're taking what they, what the information they have to figure that out. You know, you could look at, uh, single cells doing that. I think the joy of intelligence is really in every living thing. I think every cell is intelligent. I think everything that comes from cells is intelligent.

• 12:53Manoush Zomorodi?

  That's Greg Gage. He's a professor at the University of Michigan and co-founder of Backyard Brains, a company that builds neuroscience experiments for kids. You can find all his talks at ted.com. On the show today, natural intelligence. I'm Manoush Zamirodi, and you're listening to the TED Radio Hour from NPR. We'll be right back.

• 13:31Speaker 05

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• 14:36Manoush Zomorodi?

  It's the TED Radio Hour from NPR. I'm Manoush Zomorodi. On the show today, natural intelligence, which is actually where some computer scientists are looking for inspiration to design the next generation of artificial intelligence.

• 14:54Speaker 07

  Yeah, so African dung beetles, they roll up balls of feces and balls of dung and roll them away as quickly as they can.

• 15:02Manoush Zomorodi?

  Because even the smallest creatures on Earth can execute some amazing feats.

• 15:08Speaker 07

  So they're standing on their head, they're rolling the ball of dung with their hind legs, and they're using various cues to roll in a straight line. If they're nocturnal, they're known to use moonlight to be able to make sure that they're going in a straight line. And I wouldn't be able to roll anything standing on my head.

• 15:26Manoush Zomorodi?

  This is Frances Chance.

• 15:28Speaker 07

  Sahara desert ants, when they find food and they want to bring it back to their nest, they know how to calculate the straightest path back to their nest.

• 15:35Manoush Zomorodi?

  Frances sounds like an entomologist.

• 15:37Speaker 07

  Oh, and honeybees, you know, they also forage.

• 15:40Manoush Zomorodi?

  But she's actually a computational neuroscientist. At Sandia National Laboratories, she researches how natural intelligence can help develop new security technology. For example, what missile defense systems might learn from the dragonfly.

• 15:57Speaker 07

  So they're very good at what they do.

• 15:59Manoush Zomorodi?

  These graceful, fluttering creatures also use a very special technique to hunt.

• 16:07Speaker 07

  Dragonflies are really good at hunting. We know that they fly to intercept their prey. They fly really fast, and they're very successful. It's known that dragonflies catch up to 95% of the prey that they choose to go after. And even though they're really fast, they don't just fly straight at their prey. They fly on an interception pathway, which means they're aiming slightly ahead of where their prey are.

• 16:36Manoush Zomorodi?

  So is that like Gretzky, the hockey great, saying like, "Don't go to where the puck is, go to where the puck is going to be?"

• 16:43Speaker 07

  Exactly. We need to aim ahead of where the puck is going to be.

• 16:46Manoush Zomorodi?

  Mm-hmm.

• 16:48Speaker 07

  And so the dragonfly is constantly reacting to changes of the prey's direction or the prey's speed to calculate how far ahead of the prey they need to aim.

• 17:00Manoush Zomorodi?

  By understanding how these nearly instantaneous calculations happen in the dragonfly's brain, Frances hopes to build AI that mimics it and is just as efficient. Here she is on the TED stage.

• 17:16Speaker 07

  So when dragonflies are hunting, they do more than just fly straight at the prey. They fly in such a way that they will intercept it. They aim for where the prey is going to be. To do this correctly, dragonflies need to perform what is known as a coordinate transformation, going from the eye's frame of reference, or what the dragonfly sees, to the body's frame of reference, or how the dragonfly needs to turn its body to intercept. And dragonflies are fast. This means they calculate fast.

• 17:44Speaker 08

  The latency, or the time it takes for a dragonfly to respond once it sees the prey turn, is about 50 milliseconds. So, in the brain, a computational step is a single neuron or a layer of neurons working in parallel. It takes a single neuron about 10 milliseconds to add up all its inputs and respond. The 50-millisecond response time means that once the dragonfly sees its prey turn, there's only time for maybe four of these computational steps, or four layers of neurons, working in sequence, one after the other, to calculate how the dragonfly needs to turn. In other words, the neural circuit that I need to understand

• 18:27Speaker 08

  can have at most four layers of neurons. This is a small neural circuit, small enough that we can identify it and study it with the tools that are available today. And this is what I'm trying to do. I have built a model of what I believe is the neural circuit that calculates how the dragonfly should turn. In a computer simulation, I can predict the activities of individual neurons while the dragonfly is hunting. To test the model, my collaborators and I are now comparing these predicted neural responses with responses of neurons recorded in living dragonfly brains. These are ongoing experiments in which we put living dragonflies in virtual reality.

• 19:11Speaker 08

  Now, it's not practical to put VR goggles on a dragonfly. So, instead, we show movies of moving targets to the dragonfly, while an electrode records activity patterns of individual neurons in the brain. If the responses that we record in the brain match those predicted by the model, we will have identified which neurons are responsible for coordinate transformations. The next step will be to understand the specifics of how these neurons work together to do the calculation. But this is how we begin to understand how brains do basic or primitive calculations.

• 19:48Manoush Zomorodi?

  So you are building computer models based on the dragonfly's brain that can intercept things in just a few steps. The dragonfly, it must be doing really complicated math really fast. Is that what you are trying to figure out, those calculations?

• 20:04Speaker 08

  Yeah, so what I'm really interested in are what are the fundamental operations that neurons are capable of? Or what are the fundamental operations that neurons do? And that's what I want to bring to a computer. It may be something like basic trigonometry, or it may be something that's kind of a different type of math than we're used to thinking about. But that's what we're trying to understand. Because if we can understand the operations, then we can begin to understand what the algorithms, or say, the computer programs of the brain are. The way that these neurons compute may be different from anything that exists on a computer today. And the goal of this work is to do more than just write code that replicates the activity patterns of neurons.

• 20:49Speaker 08

  We aim to build a computer chip that not only does the same things as biological brains, but does them in the same way as biological brains. This could lead to drones, driven by computers the same size as the dragonfly's brain, that capture some targets and avoid others. Personally, I'm hoping for a small army of these to defend my backyard from mosquitoes in the summer. The GPS on your phone could be replaced by a new navigation device based on dung beetles or ants that could guide you to the straight or the easy path home. And what would the power requirements of these devices be like? The human brain is estimated to have the same power requirements as a 20-watt light bulb.

• 21:34Speaker 08

  Imagine if all brain-inspired computers had the same extremely low power requirements.

• 21:40Speaker 08

  Your smartphone or your smartwatch probably needs charging every day. Your new brain-inspired device might only need charging every few months, or maybe even every few years.

• 21:50Speaker 07

  You know, computers touch us in all sorts of ways that we totally take for granted. But one resource that limits what computers can do today is being able to power them.

• 22:03Manoush Zomorodi?

  Yeah, and you you mention a future scenario where maybe we wouldn't need to charge our devices every day. Maybe we could go months or even years. Could we potentially scale back big time from using all the energy we need right now to run massive servers and data centers all over the world?

• 22:24Speaker 07

  Yeah, I think that it could have long-reaching impacts by decreasing just human carbon energy footprint on the world. Definitely. As it is, a lot of these data centers need to be next to some natural resource, like a river, to be able to generate enough power to use these algorithms like Google Search. So I think that there's a lot of potential there that we may be able to bring that cost down.

• 22:52Manoush Zomorodi?

  So bring this back to what you do at Sandia for us. I mean, I know you can't get into the details, but when it comes to national defense, it makes me think of Israel's Iron Dome. And leaving aside the politics, is the aim to find ways to make missile defense systems like those more efficient?

• 23:13Speaker 07

  Well, I, you know, Sandia is interested in national security missions that requires a lot of computer power. I'm not necessarily going to talk about what those are. But if we're doing our job, you won't necessarily see the impact of that.

• 23:30Speaker 07

  So being able to understand how neurons do what they do for low power means that the cost of each of these individual operations, or the cost of each of these interactions of a human with, say, something in the cloud, is going to come down. And so what I'm interested in is how the dragonfly brains are able to do this calculation with low power and really remarkably fast.

• 23:58Manoush Zomorodi?

  There is a debate about whether artificial intelligence can actually be intelligent. What about the dragonfly? Do you think of it as intelligent?

• 24:09Speaker 07

  Yeah, so I think there are a lot of different definitions to what intelligence is. When I think about human intelligence, it's our ability to adapt or take in new information and behave differently based on new situations. For dragonflies, they're examples of neurons solving a task in what I would say is maybe even an optimized way. You know, the dragonfly has evolved to do this particular task very well, very fast, very efficiently. So I call them clever, you know, clever solutions. They're examples of what intelligence could produce.

• 24:52Manoush Zomorodi?

  That was computational neuroscientist Frances Chance. You can see her full talk at ted.com. On the show today, ideas about natural intelligence. So far, we've heard about plants that can count and dragonflies that intercept their prey in milliseconds. But what about our own natural intelligence? The one in our bodies? How are you feeling?

• 25:20Speaker 09

  I'm feeling not so good.

• 25:25Manoush Zomorodi?

  That's our senior producer, Sanaa, and her daughter, Mina.

• 25:29Speaker 09

  I feel a little nauseous, like there are pebbles or rocks in my stomach and my head just occasionally it hurts.

• 25:44Manoush Zomorodi?

  Mina is homesick with a virus, and she doesn't want to do much of anything.

• 25:50Speaker 09

  Right now, I'm sitting on the couch. I just want to watch a movie and like watch something on my iPad.

• 26:04Manoush Zomorodi?

  As we know, these symptoms are coming from Mina's immune system that is trying to fight off that virus. Leading the charge are molecules called cytokines.

• 26:15Speaker 10

  They're basically like the chemical messengers of the immune system.

• 26:21Manoush Zomorodi?

  Keely Muscatell is a psychology and neuroscience professor at UNC Chapel Hill. That's where she studies the links between our physical and mental health. And she says these cytokines float around in our bloodstream, looking for anything suspicious. And when they find something, they sound the alarm.

• 26:42Speaker 10

  It's like, oh, there's a problem here. We need to do something to try to contain this. And it's trying to signal to other immune cells to come and like, try to figure that out.

• 26:55Manoush Zomorodi?

  And that causes inflammation.

• 26:57Speaker 10

  And that's what we tend to experience when we have, you know, been infected with a virus or some sort of other pathogen, is that widespread systemic inflammation. Now, in doing this, cytokines cause the physical symptoms we commonly have when we're sick.

• 27:14Manoush Zomorodi?

  Keely Muscatell continues from the TED stage.

• 27:17Speaker 10

  Things like fever and achiness and fatigue. So even though we usually think of those symptoms as being caused by a virus or a bacteria itself, they're actually caused by our own immune systems, activating to try to eliminate the pathogen. But in addition to those physical symptoms, decades of research, both animals and humans, clearly shows that cytokines also cause changes to our mood and to our social behavior. So inflammation in the body can signal to the brain to cause us to feel down, depressed, and even hopeless.

• 28:01Speaker 10

  Inflammation can also make us want to socially withdraw from other people, to avoid interacting with individuals in our social networks. So this research shows the powerful influence that the immune system can have on our mood and on our social behavior. Changes in inflammation in the body can signal to the brain to cause us to feel depressed and even lonely.

• 28:28Manoush Zomorodi?

  You know, earlier, we heard from our colleague's daughter, who was homesick. And she loves school, she loves sports, but she did not feel like doing anything that day. And that's exactly what you're describing.

• 28:41Speaker 10

  Yeah.

• 28:42Manoush Zomorodi?

  That when we are sick, it is actually our immune system saying, "Stay home." Yeah, it's OK that you're a little depressed. Just lie down.

• 28:53Speaker 10

  Exactly, exactly. So your body is gonna send signals to your brain that cause kind of a loss of joy or a loss of interest or pleasure in things that normally would bring you tons of joy, like going to school or, you know, whatever it is that makes you really happy. And the idea is that that's a really good thing, right? Because if you're sick, then you really should be staying home and letting your body recuperate and recover, letting your immune system do its job. And also kind of containing the possibility of spreading whatever you have to other people.

• 29:31Speaker 10

  While we can't know for sure why this happens, evolutionary theory provides some good food for thought. The fact is, revving up and running the immune system takes a lot of energy. Getting cytokines to swim through the bloodstream and send signals to immune cells takes calories. And what else takes calories? Pretty much everything, especially things like going out and seeking pleasurable experiences, interacting with strangers, and just generally moving about the world. So the theory is that the immune system is telling the brain to feel depressed and to withdraw from socializing

• 30:14Speaker 10

  because it wants you to stay at home and rest.

• 30:19Speaker 10

  And if things that would normally sound fun just don't seem all that fun, and if interacting with other people seems exhausting and maybe even a little threatening, then we'll be less likely to do those things and more likely to stay at home and let our immune systems use our calories. But it turns out, the influence of inflammation on our social lives isn't as simple as always making us feel more disconnected and socially withdrawn. One of the most important discoveries that we've made in this area of research recently is that inflammation might actually make us more motivated to seek some social interactions,

• 31:03Speaker 10

  specifically those with the people who we're closest to. So it's not that inflammation makes us less social across the board. It may just make us more motivated to seek interactions with people who could provide us with comfort or care, those who could be a shortcut to chicken soup.

• 31:24Manoush Zomorodi?

  This all feels incredibly intuitive, but it's also fascinating that there are evolutionary reasons why my body is making me feel this way when I don't feel well.

• 31:37Speaker 10

  Totally.

• 31:38Manoush Zomorodi?

  Would it be fair to say, though, that our immune system is smart?

• 31:44Speaker 10

  Yes, I think it is. I think it is smart. I think it evolves to do its job and do its job very well. And what I think is really interesting for for humans is that it's also evolved in the context of having this brain that is able to ignore it. And there's kind of that push and pull there where I think the immune system sends those like appropriate signals to the brain, but we have this beautiful prefrontal cortex that can say, I hear you, immune system, but no, I'm not going to take these steps to help myself recover. And that's the cutting edge of of being a human and having the brains that we do.

• 32:28Manoush Zomorodi?

  The brain can be the idiot, no matter how smart the immune system is being.

• 32:32Speaker 10

  Yeah, kind of. I kind of think that's true.

• 32:36Manoush Zomorodi?

  In a minute, Keely Muscatell explains what can happen when inflammation doesn't go away and becomes chronic. On the show today, natural intelligence. I'm Manoush Zamirodi, and you're listening to the TED Radio Hour from NPR. Stay with us.

• 33:09Speaker 06

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• 34:25Manoush Zomorodi?

  It's the TED Radio Hour from NPR. I'm Manoush Zomorodi. On the show today, ideas about natural intelligence. We were just talking to Keely Muscatell. She's a social psychoneuroimmunologist, which means...

• 34:41Speaker 10

  I study the relationship between the immune system and social behavior.

• 34:46Manoush Zomorodi?

  Keely says that, over the years, research has shown that inflammation in our body affects our mood and our behavior.

• 34:57Manoush Zomorodi?

  So we hear about inflammation, I feel like, all the time right now. Like, you know, the hot thing is to be on an anti-inflammatory diet and to eat blueberries and almonds rather than processed foods. But are we talking about a different kind of inflammation? And if you don't eat healthy, we think of that, you know, you're not consuming the right fuel to give you energy and maybe you do feel depressed, but are those different?

• 35:23Speaker 10

  No, exact same, exact same process, same, same inflammation that you have in response to like an acute infection is part of what's contributing to chronic disease. And that is responsive to the types of things you put in your body, the amount of physical activity that you engage in, the amount of sleep you get. I'm a new mom, I've been chronically sleep deprived for the last 11 months and it's been great, but also I often wonder, you know, how much of an impact is this sleep deprivation having on the levels of inflammation in my body? And how is that influencing, you know, my mood and my ability to think clearly and engage with others?

• 36:07Speaker 10

  So, yeah, it's not to say that these responses that the body has to acute instances of sickness or infection, or even stress are, I think, adaptive, but if they play out over a long time course, that could be really tough for people. And I think especially in the face of, of chronic stress, it's sort of this spiral, right? Where stress can cause inflammation, that inflammation can signal the brain, you know, for people to maybe disconnect or withdraw, which can lead to more stress. You don't have the same support network that you had or that you need. And that can be a really tough cycle to break.

• 36:49Manoush Zomorodi?

  So it's not just a matter of, come on, go and get yourself out there. There's a lot more going on behind the scenes.

• 36:54Speaker 10

  100%.

• 36:56Manoush Zomorodi?

  All right, so this baby that you've got, when they grow up and they're like, Mom, I don't feel well, I want to stay home, what will you say?

• 37:03Speaker 10

  Oh my God, that's such a good question. I've thought about this a lot. I mean, because this is the other thing about human brains, right? Is like can also be deceitful. And I guess I hope that little baby Archer doesn't want to just stay home to hang out with me and watch cartoons or whatever, but. What I hope is that we can teach him that signals from our bodies are important to listen to. And the other thing this makes me think of is that I'm so fortunate to have a job in a position where I could stay home with him. I would be able to accommodate those signals.

• 37:46Speaker 10

  And I really feel for people who don't have that safety net and who might have to push their kids to go out and go to school even when they're not feeling well. So maybe Archer can also push for some broad scale society change in terms of giving people the sick time they need.

• 38:05Manoush Zomorodi?

  No pressure, Archer.

• 38:06Speaker 10

  Yeah, exactly.

• 38:09Manoush Zomorodi?

  That's Keely Muscatell. She's a professor of psychology and neuroscience at the University of North Carolina Chapel Hill. You can see her full talk at ted.com. And many thanks to Mina Meshkempur Agdam too.

• 38:25Speaker 09

  Do you want hugs from mommy?

• 38:27Manoush Zomorodi?

  Uh huh. And kisses.

• 38:38Manoush Zomorodi?

  To close our show on natural intelligence, we want to talk about how animals communicate to each other and what they're saying. Scientists are using new technologies to try and translate different species' conversations, specifically using artificial intelligence to interpret their sounds. Environmental researcher Karen Bakker explained how these technologies work and what they're revealing in a talk she gave in 2023. Tragically, Karen died just a few months after giving her talk, and so we want to share with you now the entirety of it. Here's Karen Bacher on the TED stage.

• 39:21Speaker 11

  So we're in the middle of a fierce debate about how artificial intelligence will change human society. But have you thought about how AI will transform your relationship to the non-human world? So these are bioacoustic recorders, and I've spent years studying how scientists use devices like this combined with AI to listen to the hidden sounds of nature and decode non-human communication. Hidden sounds, because much acoustic communication in nature occurs in the high ultrasound, above your hearing range, or in the deep infrasound, below your hearing range. So I'm gonna play a sound.

• 40:03Speaker 11

  I want you to listen and try to guess who or what this is.

• 40:18Speaker 11

  So that was a bat. That was bat ultrasound, recorded above your hearing range, but slowed down so you could hear. So that was an advertisement call from the peak of the mating season. Scientists can decode these calls. So a sample bat-to-English translation would be, and I quote, "Pay attention. I'm a Pippastrellus matuzzi bat, specifically male. My name is X. I am landing here, and we share a common social identity and common communication pool." For a pickup line by a bat, not that. So scientists have recorded millions of bat vocalizations like this, and they've decoded many of them using AI. And they've revealed that bats have dialects

• 41:02Speaker 11

  that they pass down from one generation to the next, and that baby bats learn to speak just like you did by listening to the adults around them and babbling back until they speak adult bat. So bats have far more complex communication than we knew, and they're only one of many examples. Listen to this.

• 41:30Speaker 11

  So those are orcas. Scientists can decode individual orca calls using AI, and they've revealed that orcas also pass down their dialects from one generation to the next. So when we first learn about these secret sounds of the world, we're often surprised because humans tend to believe that what we cannot perceive does not exist. And so we miss a lot. One of my favorite examples is this peacock. So to you, this looks like a visual mating display, and it is. But this peacock is also making very loud infrasound with its tail, which you cannot hear, but female peahens can. And it is an important factor in their mating decisions.

• 42:12Speaker 11

  So this peacock is giving a rock concert. Now, we have lived with peacocks for millennia, but we only just figured this out. Even creatures without ears are exquisitely sensitive to sound. So this is a coral larva. When coral larvae are born, usually at a mass spawning event, a few days after the full moon, they wash out to sea. So scientists used to think that these little larvae, these tiny dots that you see here, were helpless, randomly pushed around by wind and waves and currents. But it turns out that coral larvae are acoustically attuned. They can hear the sounds of healthy reefs. They can hear the sound of their home reef, their mother reef, and they swim back home

• 42:57Speaker 11

  across miles of open ocean. So these are tiny creatures with no central nervous system. But we think they do that with these hairs that you see on the outside of their bodies. They're a lot like the hairs inside your ears that are enabling you to listen to me right now. So you can think of a coral larva a little bit like an inside-out ear, except that its sense of hearing is profoundly more sensitive than your own because they hear with their entire bodies. Even our planet makes sound. Volcanoes, earthquakes, sound so low and strong and powerful, they travel very far, passing through soil and stone

• 43:40Speaker 11

  and even solid walls. So in nature, sound is everywhere, and silence is an illusion.

• 43:51Speaker 11

  So scientists are also listening to the vast extent of interspecies communication. So this bat is using ultrasound to hunt this moth. Its echolocation beam is locked onto its prey. But the moth is also emitting ultrasound. It's jamming the bat's sonar in an attempt to escape. This plant is also emitting ultrasound, which varies depending on its condition. Scientists have trained an algorithm to listen to this plant. Simply by listening, it can detect with about 70% accuracy whether the plant is healthy, dehydrated, or injured. So this is peer-reviewed research, by the way.

• 44:35Speaker 11

  So we cannot hear these sounds, but we think many insects can. Does this mean that humans could use digital tech to one day communicate with other species? Well, some scientists think so, and they're using machine learning to try to decode the acoustics of other species. So there are teams of computer scientists and linguists and biologists working on decoding sperm whale bioacoustics. They're also building entire dictionaries. So there's an elephant dictionary with thousands of sounds. Elephants, for example, have a specific signal for honeybee. So I'd love to share just one of these sounds with you. It was recorded at a moment of great joy and celebration,

• 45:19Speaker 11

  the birth of a new baby.

• 45:38Speaker 11

  So the further we listen across the Tree of Life, the more complex interspecies communication would be. Listen to this honeybee.

• 45:54Speaker 11

  Now, listen to this honeybee queen.

• 46:05Speaker 11

  So you thought you knew what honeybees sounded like? Okay. Honeybee communication is incredibly complex. It's acoustic, positional, spatial, vibrational. The queen has her own signals. So scientists are encoding these signals into robots. This robot is attempting but not succeeding to communicate with the hive. The bees mostly ignore or attack it. But, one day, we hope, the inventors hope, that this robot will communicate well enough to allow scientists to monitor the health of the hive. Now, would that be a good thing? Some believe that interspecies communication would help foster respect and empathy for nature. Others believe that it is profoundly disrespectful

• 46:49Speaker 11

  and unethical to eavesdrop and engage in this way. Interspecies communication needs strong ethical guardrails. And anyway, maybe it's a bit self-centered to think other species would even want to communicate with us. So, what if we were to use bioacoustics for something of immediate practical value? Like, doing something about our massive biodiversity crisis? Let's go back to the coral reefs. Listen to this healthy reef sound.

• 47:29Speaker 11

  Pretty lively, right? But coral reefs are disappearing. If you were to go to most coral reefs today, you'd hear something like this.

• 47:43Speaker 11

  It's like a ghost town of the sea. When we lose species, we lose voices. When we lose landscapes, we also lose soundscapes. There is a ray of hope. The healthy reef sounds that you just heard can be used to regenerate coral reefs. Scientists are doing this. It's a bit like music therapy for nature. So this is not going to solve all the problems coral reefs face, notably, climate change. But, if we can address the massive epidemic of noise pollution that is harming and killing marine creatures, we could use bioacoustics to restore some biodiversity.

• 48:19Speaker 11

  Bioacoustics could also help protect animals on the move. So this baby whale was killed by a ship tragically. This is a common cause of death of North Atlantic right whales, one of the most endangered species in the world. So to address this, scientists are now launching a new bioacoustics program off the east coast of North America to triangulate the locations of whales and convey the information to ship captains in real time. The ships then have to slow down, stop, move out of the way. Not a single right whale has died of a ship strike in this zone since this program was launched.

• 49:02Speaker 11

  So this may be the thing that saves this species. So think about it, a few decades ago, we were harpooning these whales nearly to extinction. Today, we've invented a technology that allows a community of less than 400 whales simply by singing to guide the movements of tens of thousands of ships in a watershed that's home to tens of millions of people. One day, these whale lanes may be everywhere in the oceans. For the orcas who live here in the Sailor Sea, this would be just in time because there are only a few dozen left. A final thought.

• 49:41Speaker 11

  About 400 years ago, the inventors of the telescope were gazing up at the stars, not knowing their invention would allow humanity to look back in time to the origins of the universe. Optics decenters humanity within the solar system, within the cosmos. Bioacoustics decenters humanity within the tree of life. Our commonality is greater than we knew.

• 50:09Speaker 11

  Now, today, we're using bioacoustics to protect species and decode their communication. But tomorrow, I believe, we'll be using bioacoustics combined with machine intelligence to explore the frontiers of biological intelligence. Many biological intelligences are very different than our own, but they're no less worthy of exploration. And maybe one day, in a speculative future, instead of a human here on stage, maybe bioacoustics would enable an orca to give a TED Talk.

• 50:40Speaker 11

  Why not? Sharing orca stories about dodging ships and seismic blasts and human hunters, stories about desperately seeking the last remaining salmon, stories about trying to survive on this beautiful planet in this crazy moment in our era of untethered human creativity and unprecedented environmental emergency. Now, those would be ideas worth spreading.

• 51:11Manoush Zomorodi?

  That was Karen Bakker. Her latest book is Gaia's Web: How Digital Environmentalism Can Combat Climate Change, Restore Biodiversity, Cultivate Empathy, and Regenerate the Earth. And we want to dedicate this entire episode on natural intelligence to her. Thank you so much for listening. This episode was produced by James Delahoussaye, Harsha Nahada, Katie Monteleone, Matthew Cloutier, and Fiona Guerin. It was edited by Sanaz Meshkhanpour and me. Our production staff at NPR also includes Rachel Faulkner White. Irene Naguchi is our executive producer. Our audio engineers were Robert Rodriguez and Gilli Moon.

• 51:56Manoush Zomorodi?

  Our theme music was written by Ramtin Arablouei. Our partners at TED are Chris Anderson, Michelle Quint, Alejandra Salazar, and Daniela Balarezo. I'm Manoush Zamirodi, and you've been listening to the TED Radio Hour from NPR.

• 52:14Speaker 05

  Stay tuned for the following announcements and messages from our sponsors.