Science Friday - How A Woodpecker Pecks Wood, And How Ants Crown A Queen

Episode Date: November 17, 2025

If you’ve heard the hammering of a woodpecker in the woods, you might have wondered how the birds can be so forceful. What does it take to whack your head against a tree repeatedly, hard enough to drill a hole? A team of researchers wondered that too and set out to investigate, by putting tiny muscle monitors on eight downy woodpeckers and recording them with high-speed video as they pecked away in the lab.Integrative organismal biologist Nick Antonson, co-author of a report on the work, joins Host Flora Lichtmen to peck away at the mystery.Plus, you can take two ant eggs with the exact same genes, and one can grow up to be a queen, the other a worker. Neuroscientist and evolutionary biologist Daniel Kronauer joins Flora to share recent research into how an ant becomes a queen.Guests: Dr. Nick Antonson is an NSF postdoctoral research fellow in the department of ecology, evolution, and organismal biology at Brown University.Dr. Daniel Kronauer is the Stanley S. and Sydney R. Shuman Professor in the Laboratory of Social Evolution and Behavior at The Rockefeller University in New York.Transcripts for each episode are available within 1-3 days at sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

I'm Flora Lickman, and you're listening to Science Friday. Today in the show, how do you drill a hole with your head? They're engaging everything from head and neck muscles, which you might expect, all the way down to muscles in their tail and hips. If you have heard the hammering of a woodpecker in the woods, you may have wondered, how do they do it? What does it take to whack your head against a tree repeatedly, hard enough to drill a hole? Well, a team of researchers wondered that, too, and set out to investigate by putting tiny muscle monitors on eight downy woodpeckers and watching them with high-speed video as they pecked away in the lab.

Joining me now is one of those researchers. Dr. Nick Antensen, he's an NSF postdoctoral research fellow at Brown University and an author of a report on the work in the Journal of Experimental Biology. Nick, welcome to Science Friday. Thank you, Flora. Okay, I love this question, but why this question? Yeah, so what we were really excited about with this question in particular is, you know, all birds peck, but woodpeckers are really special in that they take this to the extreme. And by investigating extreme behaviors, we can kind of figure out what the performance limits are of what things like muscles are actually able to do. When you say that woodpeckers take it to the extreme, how hard do woodpeckers peck?

A woodpecker can peck at about 20 to 30 times their body weight. What it feels like if you get pecked by one, as it feels like a sharp pinprick. That's actually really impressive for a bird that weighs about as much as a single double A battery. Well, I was going to ask, I mean, 20 to 30 times your body weight, is that a lot? Like, when I'm hammering, am I hammering as hard as a woodpecker or harder? So you would be hammering probably harder than what a woodpecker does. But with the woodpeckers, what's interesting is it's all of that hammering force down to a pinpoint. And so that's what we were really excited to set out to investigate here.

It's so much more than the force that your normal bird pecks with. So what did you find? What is driving this drilling power? I think one of the most stunning things that we found in this study was that it's muscles across the body of the woodpecker. And so they're engaging everything from head and neck muscles, which you might expect, all the way down to muscles in their tail and hips as they push forward during these strikes. I mean, this reminds me of my high school soccer coach, who would often tell us that if we were doing a header, we had to use our whole body. Yeah, absolutely. You just build more force that way. And the other thing that was really exciting with this, too, that I'm sure your soccer coach probably also would have recommended is to grunt while you do it.

And so the woodpeckers do that too, where they're actually grunting through each one of these strikes. Can you hear it? So you can't hear it. It unfortunately gets masked by the percussion of the drum beats that they're making. But we were able to actually measure the respiratory pressure from their respiratory system to tell when these birds were exhaling versus when they were inhaling. So that's what you mean by grunt. They did like a big exhale? Yes, they exhale straight through the strikes, similar to how, you know, an athlete like Serena Williams will when she's striking a tennis ball. What happens is by stabilizing those core muscles while you exhale, you can add extra power to those strikes in all of those instances. The grunt is making them stronger. Yes, so the grunt is actually making them stronger.

Can you make the sound for us, like what you would imagine it to sound like? I can give it my best shot. The other thing that's interesting about it, that I'll just add to that before I make the sound, because it'll give some context to the specific sound I'm making, is that they can do this repeatedly as well, and up to like 13 times per second. They can exhale on every single one of the strikes. And so if I were to kind of make the sound, I think it would sound something like, ha ha, ha, ha.

So to us, that sounds like hyperventilation, but to them, this is just like well, within their respiratory capabilities. Amazing. How do they deal with kickback? Like, why don't they fly backwards after they hit the tree? Yeah. So another one of the really exciting things we found is that when these birds are going in for these strikes, the first things they do is they'll activate the neck muscles that pull the

head forward. Then it's the hip flexors to pull the entire body forward. Then their tail pushes against the tree as a brace. And then following that, there's a collection of head and neck muscles on the back of the head that actually stiffen. And so right as they're going into that strike, they engage those abdominal muscles to exhale and then push their way into the wood. And so they're not just bouncing off and their neck's not just like collapsing as they take the force of basically a car crash. They're powering their way into the strike. And then they very measuredly just pull themselves back out

and inhale as they're pulling themselves back out. Wow. Sounds like there's a lot of choreography here, muscle choreography in their bodies to achieve this. Absolutely. And we looked at this as well, specifically with the repetitive strikes that these birds are performing, where they're pecking multiple times in a row without taking a break. And one of the really striking things that we found in doing that was that the timing of when they're activating each of these muscles in sequence was incredibly precise.

was incredibly precise. And so there was never kind of a misfire where one muscle fired out of order where it wasn't supposed to. Let's talk about the experimental setup. Was it difficult to get the woodpeckers to peck in the lab? So the woodpeckers are voracious. And so they actually love to peck on any wood that you provide for them. As many homeowners know. As many homeowners know, yes. So in order to collect the data, we had these birds hooked up to their sensors, and then those sensors actually went to a custom-made backpack for each bird so that it comfortably rested on their back, so that they could freely move throughout our recording chamber and peck on kind of a variety of woods. So we gave them kind of a charcutory board of different woods to peck from.

Are there any other special adaptations that a woodpecker has to live this pecking lifestyle? Yeah. So I think one of the most exciting other things that we've found with the woodpeckers was that they can exhale on every single one of those strikes. They can exhale at a rate of 13 times per second. And then as they're pulling away with each strike, they can inhale on the order of 40 milliseconds, which is less than the blink of an eye. To take a quick breath in and get ready to oxygenate all of those muscles and their airways between each one of those strikes. And in birds, this is really only a respiratory adaptation we've seen to this point in songbirds when they're doing their singing behaviors. They can intersperse these little inspiration breaths

between each one of the syllables of their song. And so woodpeckers aren't very closely related to songbirds. And so it's really interesting to find that woodpeckers have found a similar adaptation for their pecking behaviors. Okay, while I have you, Nick, I have a very important question. I've heard for many years that the tongue of a woodpecker wraps around its brain, and the purpose of that is that it's a shock absorber. True? No.

So actually that it's become a very popular science myth. And so... That's the second gasp. I've gasped twice. So what's interesting about this is their tongues do wrap around their head, but they wrap around the outside of the skull. And so they're not providing kind of the cushioning to the brain. The brain is still smacking against the front of the skull when they're doing these repetitive impacts. What the tongue wraps around the skull for is actually to be a projectile.

So they can actually shoot their tongues like chameleons can to spear insects in the holes that they've drilled in trees. To spear them? Yeah. They're pointy at the end? Yes. So at the end of a woodpecker's tongue, there's a barb so that they can skewer through those insects. I love these birds so much. So are they wrapping, is it just that it's a convenient place to hold the tongue?

Yeah, it's a convenient place to store a really long tongue. With some woodpeckers, their tongues can even be three times the size of their head. Wow. The other thing I'll mention about this, too, is that the reason that woodpeckers don't get concussions, or at least as far as we've seen so far, is because their brains are small enough that they don't build the G force to smack against the front of the skull that would be necessary to cause a concussion. Is this just a force equals mass times acceleration thing, like small mass equals small force? Exactly. The forces that the brain is smacking the front of the skull with aren't actually enough to cause a concussion. because their brains don't weigh very much. Gotcha.

This is so fascinating, Nick. Thank you so much for taking the time to talk with us today. Thank you for having me. Dr. Nick Antinson is an NSF postdoctoral research fellow in the Department of Ecology, Evolution, and Organismal Biology at Brown University. We have to take a break, but don't go away because when we come back, what does it take to be a royal? Ant, that is.

Turns out how Aunt queens are crowned is a hot topic. in entomology circles. Stick around. Turning now to another heady creature question, how do aunt queens get crowned? This is a royal mystery because, and this is wild, you can take two ant eggs with exactly the same genes and one can grow up to be a queen and the other a worker.

How does that happen? It turns out that's a hot topic in the ant world and a recent paper provides some insights. Here to tell us more is study author, Dr. Daniel Kronauer, an evolutionary biologist at the Rockefeller University in New York City. Daniel, welcome to Science Friday. Thank you very much. You study the social lives of insects.

What drew you to this particular antill? Well, I've been really fascinated by insects since I was a little kid. So I grew up in Germany in Heidelberg, as you might be able to tell for my accent. And my mom tells the story that she often couldn't find me during elementary school pickup because it turned out that I was punched over in some hedge watching ants on the floor or looking at a beetle or something. You know, when you watch insects, they just look very exotic and almost like on a different planet or like some alien creatures. And for me, that was always very fascinating, like thinking about how they experience the world and how they communicate. and what their behavior means to them and how they live. And then I made that early childhood fascination my profession.

So your latest study is about how a queen ant becomes a queen, which I take it as kind of mysterious and a little bit of a hot topic in the ant world. Yeah, so the interesting thing is that in an ant colony, you can start with, say, two eggs that are genetically identical. And depending on how you treat those individuals, during the larval stage when they're growing up and they feed a lot, they can develop into either a queen, which is very large, lays a ton of eggs, lives quite long in some species for decades,

or you can raise it into a worker, which is small, usually can't lay eggs or doesn't lay eggs, lives only for a few months often, and performs all the other tasks in a colony. So from one genome, you can make very, very different types of organisms. Like stem cells. Exactly. I was about to say, right?

It's a little bit like you start with the stem cell, and then you make either, say, a neuron or skin cell, right? And that's actually the analogy that you hear a lot when you read about insect societies. The analogy of the insect society as an organism, or sometimes people talk about the superorganism. The superorganism. So do we understand what determines whether that ant, egg becomes a queen or a worker.

Yeah, so there's a lot of research that's being dedicated to that still, and it has a lot to do with how much food the larva gets. And so the workers can feed a larva more or less food, or they can feed it different types of food. You might have heard of royal jelly and honeybees. So if a larva gets fed a lot of royal jelly, it tends to develop into queen. So ultimately, it has a lot to do with what size the larva reaches and how large it can grow. But who's determining how much food that larva gets?

Like, and are all the larva getting the same amount of food and some just get bigger than others and become the queen? Yes, it's a bit complex, right? Like, I think the simplest scenario is that the workers who feed the larvae, right? They go out, they forge, they bring food back, and then they give the food to the larvae. Those are the ones that kind of decide how much food the larvae get. And so what a lot of ant species do is that they raise new workers or new queens. in separate cohorts. So, you know, sometimes in the spring you see kind of winged ants that kind of fly around. Those are queen ads, the bigger ones. Oh, so you can have multiple queens in a

generation. It's not one that's being picked out. No, exactly. So most ant colonies, you know, they have often one queen in the colony that lays the eggs. But when they raise queens, they raise many, many queens, like hundreds, sometimes thousands. And those queens, they have wings initially, and then they go on a mating flight. Then they mate. Then the males usually die, and the queens shed the wings. And then they start to dig a little hole in the soil, and they found a new colony. And then you have a new colony that has one. Okay, so we know that size is a biggie for determining how that queen program is going to get switched on in an ant, and size is determined by genes and by the environment. But your new study in clonal raider ants shows that it's not that simple,

Right? Yeah, I would say if you wanted to distill these findings down into kind of one main conclusion, it's that basically what the study shows is that there are genes that affect the body size of an individual and therefore the caste phenotype. And then there are genes that affect the relationship between the caste phenotype and the body size. There's basically two different ways to be a queen, right? One is to be larger and one is to have a genotype. where queen development sets on at smaller body sizes.

And when does this queen program initiate? Like, is it when they're in the larval stage after they've hatched? I mean, when do they know that they're big enough to be queen-like? That's a very good question. And I think there we still have to do a lot of work. There are some ant species where it's determined very, very early during development. You can almost tell at the egg stage. Oh, wow.

And then there's other ant species where it's probably determined pretty late during the larval stage, right? And it really only becomes clear once the larva enters a pupation, basically metamorphosis. So there's a lot of diversity in ants, I think. And that's going to be very interesting to study more carefully at the developmental level and at the molecular level. I mean, is it good to be the queen? Would you want that if you were an ant? So, yeah, exactly, right? You think of the queen as the one individual in a colony that has all the power.

But in ants, that's not really true, right? Like, the queen is basically this individual that just lays eggs and doesn't do much else. I don't know. That sounds horrible, actually. It's almost like an egg laying machine or something. So I wouldn't, you know, I don't know if I would want to be an ant queen. So I was reading that this is a hot topic in the ant world. Yeah.

Tell me why. What's the drama around this? Well, I think it's just a very interesting question, right? It's this extreme case of what people call phenotypic plasticity, right? A lot of developmental biology, evolutionary biology, is about this question of what's classically discussed as nature versus nurture, right? Like how much of your existence or your phenotype, the way you are is determined by the genes you inherit it, and how much is determined by, the environment you've experienced, right? Or maybe even chance events. And that's a, it's a really interesting and important question.

And I think ants are just very, very well suited to address those questions. Daniel, thanks for talking to me today. Thank you so much for having me. Thanks for listening. Don't forget to rate and review us. Wherever you listen, it really does help us get the word out and get the show in front of new listeners. Today's episode was produced by Charles Brawerex. Burquist. I'm Flora Lichtman. Thanks for listening.