The Extreme Maneuverability of Hummingbirds, with Roslyn Dakin
33:50 Share

This is an iHeart Podcast. When you're part of a military family, you understand sacrifice and support. At American Public University, we honor your dedication by extending our military tuition savings to your extended family. Parents, spouses, legal partners, siblings, and dependents all qualify for APU's preferred military rate of just $250 per credit hour for undergraduate and master's level programs.

American Public University. Value for the whole family. Learn more at apu.apus.edu slash military. Toyota is the best resale value brand for 2025, according to Kelley Blue Books, kbb.com. And with a wide range of dependable vehicles for any lifestyle, you can get everything you need in a vehicle today while investing in tomorrow. So choose Toyota and choose value. Shop

Buy at Toyota.com for great deals and more. Vehicles projected resale value is specific to the 2025 model year. For more information, visit KelleyBlueBooksKBB.com. Kelley Blue Book is a registered trademark of Kelley Blue Book Co. Inc. Toyota, let's go places.

Wells Fargo is proud of the important role they play for their customers, their communities, and the U.S. economy, covering more rural markets than many large banks and nearly 30% of branches in low- or moderate-income census tracts, also proudly serving more than 10% of small businesses nationwide.

Wells Fargo, the bank of doing. Learn more at wellsfargo.com slash say do. Wells Fargo Bank N.A., member FDIC. Today's episode is brought to you by USPS. I know, I know, you've got your shipping game on lock. But did you know, with USPS Ground Advantage service, it's like your shipment has a direct line to you.

You're in the loop the whole time. It leaves the dock, you know about it. It's on the road, boom, you know. And when it reaches your customer, you guessed it, you're in the know again. Here's the real game changer. It's one journey, one partner, total peace of mind. Check out USPS Ground Advantage service at usps.com slash in the know. Because if you know, you know. Welcome to Stuff to Blow Your Mind, a production of iHeartRadio.

Hey, welcome to Stuff to Blow Your Mind. Robert Lamb here. In today's episode, I'm going to be chatting with Rosalind Dakin, associate professor at Carleton University in Ottawa and principal investigator at the Dynamic Behavior Lab.

We're going to be chatting about hummingbirds as she and her co-authors just had a new paper published in the Journal of Zoology, Turning Tradeoffs. Hummingbird power reserves are used to decrease turning radius or increase turning velocity. So without further ado, let's jump right into the interview.

Hi, Rosalind. Welcome to the show. Hi, thanks for having me. So we're going to be talking about hummingbirds today. We're already really enjoying the company of hummingbirds down here in Atlanta. Have they arrived up there where you are? You're in Ontario, correct? Yes, exactly. I'm in Ottawa, Ontario, and they arrived the first week of May. The ruby-throated hummingbirds show up

almost like clockwork every year. It's always a joyous occasion here at my house when we finally see the first hummingbirds of the season appear at our feeders and flowers. And I think, you know, at first it's the magic of them being here, the way they move and all. But as you begin to observe them, you really begin to notice how intensely territorial they are about their flowers or about the cute little feeder we've put out for them. Can you...

Tell us, why are they so territorial about this? Sometimes as humans putting out feeders, we want to tell them, no, no, there's plenty you can share. And they're generally not having any of that. Yeah, that's right. They have super competitive behaviors. And that's something that we've been studying in my lab. Why they're like that, I think it all comes down to their super high metabolic rates.

Their lifestyle relies on having a steady stream of calories throughout the day. And if they go even an hour without feeding, depending on how much energy fat store they have in their body, that can be death an hour without a meal. So those food sources are really, really valuable to them.

And their metabolic rates are so high, if you could scale a hummingbird's body up to the size of the average adult human, it would be like if you or I had to eat 150 large pizzas in a day. Wow. Now, how can their wings move so fast to propel them to the air? Yeah. So in order to be able to hover, hummingbirds have to beat their wings depending on the species.

between 30 to 80 times per second. So if you think about a full wing stroke, that's your arm being fully extended back, coming forward and then back again and repeating that cycle for species like ruby-throated hummingbirds 50 times every second. It's incredibly fast.

So they have, so that's why they have such high metabolic rates, the highest of any vertebrate animal per unit body mass. But they have a lot of anatomical adaptations that are required to be able to do that.

So for example, their pectoral muscles that draw the wings down, that activate the downstroke are hypertrophy. They're really, really large. But similarly, they have another muscle, the suprachoracoideus muscle that draws the wing back up.

And it's also hypertrophied. It's also extra large in hummingbirds. They have skeletal adaptations as well. So the muscle, the bones that those muscles attach to have to be larger and more robust than they are in other birds that have more typical wingbeat frequencies. And they also have dramatically modified anatomy to the bones of their wing. These are the bones that we can't see. We just see the feathered part of the wing.

But inside the hummingbird's wing, their humerus is really, really short. It's so short, it's almost like a little dot. You know, it's just a couple of millimeters in length. And their wing is mostly hand. And what that does is it means that

the heavy parts of their arm bones are drawn in close to the body to make it easier to beat those wings so fast. But it also means that those muscles that are activating those wing strokes are working over a shorter distance. And so that makes it physically possible for them to beat their wings at this incredibly high frequency. So what evolutionarily has driven this development, this arms race of hummingbirds?

Is it just their diet and how they need to feed? Is it predators? Is it other hummingbirds? How does it all come together? Yeah, that's a super interesting question and one that we have hypotheses, but it's still an active area of research. If we go back, well, let's start with looking at what we have today. The hummingbird family is extraordinarily diverse. There's 366 different species and

And they live in the Americas, so South America, Central America, the Caribbean, and some species here in North America. That's incredibly diverse. And they've radiated, they've diversified into all of these species over the past 25 million years.

And if we look at their closest relatives in the evolutionary tree, the family tree of all birds, those are swifts, which are also super agile birds. They're distributed across the globe. We have swifts in North America. We also have swifts in Europe and Asia that are aerial insectivores. So swifts are...

spend almost all of their time in the air catching flying insects. So they have to be like little fighter pilots to be able to chase down their prey. So the first hummingbirds evolved around 30 million years ago from an ancestor that was a really, really acrobatic predator in the air.

And swifts have some of the same skeletal adaptations that we see in hummingbirds. They have an enlarged keel. That's the part of the bone on the breastbone where those pectoral muscles attach. And swifts also have changes in their wing bones that we see in hummingbirds as well. So that's part of how we know where the hummingbirds fit in anatomically. But also genetic studies have established what those relationships are.

So yeah, the first hummingbird was something like an insectivore chasing down insects. And somehow, you know, maybe they started to prefer insects that were associated with flowers. And maybe that led to them consuming some nectar. We don't know exactly what happened to produce this shift towards being so specialized on flower nectar. But the other mysterious part is that...

the earliest ancestor, the earliest fossil ancestor we have of hummingbirds is not at all in the same part of the world where we have all of the species that we, we can observe today. The, um, closest fossil ancestor of hummingbirds, they come from Europe. So, um,

Fossils with a lot of those hummingbird typical features, a long bill, an exaggerated keel, and different wing proportions. Those have been found in Poland and in France and multiple places. So they arose in Europe, we think, and at some point made their way over to the Americas.

30, 25 million years ago, and from there diversified into very many species today. And a lot of that is the diversification is probably due to specializing into different areas in the Americas and in the Caribbean.

So their enhanced maneuverability and their power reserves, which we're going to get into when we start talking about your study here, this is largely for inter-hummingbird competition, or do they have aerial predators they need to worry about as well? They may have some effective predators. That's not something that we observe very often, but we see a lot of competition both between species and also within species. So

especially among males within a species competing for a territory, competing for a food resource. The other area where we see them using their acrobatic skills is when they're courting mates. So in very many species, the males will try to impress females by doing an elaborate display in the air. And the way that display goes will differ in different species.

But often they're zooming back and forth, reaching really high speeds and turning quickly as part of that display, all at the same time as they show the female their colorful plumage and sometimes like make certain sounds while they're doing those displays as well.

When it's PCS time, you know the drill. Pack, research to new base, get the kids in school, because family supports family. At American Public University, we support military families with flexible, affordable online education that moves with you. As a military spouse, your tuition rate is the same as your partner's, just $250 per credit hour. American Public University, education that moves with you.

Learn more at apu.apus.edu slash military. This July 4th, celebrate freedom from spills, stains, and overpriced furniture with Anabay, the only machine washable sofa inside and out where designer quality meets budget friendly pricing. Sofas start at just $699, making it the perfect time to upgrade your space. Anabay's

Pet-friendly, stain-resistant, and interchangeable slipcovers are made with high-performance fabric that's built for real life. You'll love the cloud-like comfort of hypoallergenic, high-resilience foam that never needs fluffing and a durable steel frame that stands the test of time.

♪♪♪

We get it. There are too many car insurance companies trying to convince you that they have the best car insurance rates. We don't think we need to convince you. We're rude, and we do car insurance differently. We don't think it makes sense to only base your car insurance rate on things that have nothing to do with your driving, like your occupation or education.

We'll be right back.

Good drivers could save up to $900 a year when they switch to Root. We're taking an old industry and making it fair. Root Insurance, because better drivers deserve better rates. Download the app today and see how much you could save. Terms and conditions apply, subject to underwriting review. See Root.com for details.

So you want to start a business. You might think you need a team of people and fancy tech skills, but listen to me when I say you don't. You just need GoDaddy Arrow. I'm Walton Goggins, an actor, and I like the sound of starting my own business, Walton Goggins Goggle Glasses. But I couldn't do this on my own.

GoDaddy Arrow uses AI to create everything you need to grow a business. It'll make you a unique logo. It'll create a custom website. It'll write social posts for you and even set you up with a social media calendar. How cool is that? Well, listen to this. For a limited time, you can get Arrow All Access for just a dollar a week for 12 weeks. We're talking all the AI power of GoDaddy Arrow plus a domain, e-commerce store, payments, professional email, a unified inbox, all the

All for less money than I spend on deep tanning lotion while sunbathing off the Amalfi Coast. You know what that sounds like? A plan. Get started at GoDaddy.com. Terms apply.

So getting into your research a bit more here, tell us a little bit about the Dynamic Behavior Lab and how hummingbirds factor into your work there. Yeah, so we are interested in differences between individuals and differences between species. And when performance is such an important part of how they survive,

How is it that, like, what determines which individuals are dominant over which others? Who's winning those competitions? What traits determine who wins? But also for individuals that are subordinate, what options do they have? How do the subdominant individuals make a living? Those are some of the questions we're studying in my lab. So we measure things like an individual bird's ability to generate power, intelligence,

in flight, and we also measure their behavior in big arenas where we can pit multiple birds against each other, competing over a food resource and seeing both who's dominant, but also how are they using flight maneuvers to outdo each other. Now, how do you go about studying something like this? Because hummingbirds, I imagine, are not easy creatures to study anyway. And then you're dealing with some difficult to measure properties here, right? Yeah, it takes a lot of patience.

And one of the nicest assays that's possible to do with hummingbirds is a load lifting assay where we can measure the maximum power they're able to generate with their flight apparatus, with those muscles that are activating the wings. And we do that assay in a chamber that's, think of like a vertical cylinder.

um, with kind of an open bright light at the top and a hummingbird at the bottom of that chamber is going to be highly motivated to fly upwards, try to escape. Um, and, and we use an assay that was developed, um, decades ago by other scientists where we put a little, um,

ring around the bird's neck that's attached to a string of beads. And when we know the weight of the beads along that chain, we can record what's happening when the hummingbird gets released from the bottom of the chamber. And if everything is set up suitably for the bird, as they try to escape upward with everything they've got, we're able to measure exactly how many weights, how many, you know, the exact weight of the beads on that chain that they're able to lift. The higher they go, they're lifting more and more weight until they hit a maximum of

and return back to the bottom of the chamber. So we're able to develop an assay that just fits with their capabilities, their motivations to measure their maximum weightlifting ability. So essentially the tiny necklaces on hummingbirds is a part of the study? Exactly. Yeah, yeah, yeah. So we have to make those necklaces. Yeah. Oh, wow.

So this latest study published in the Journal of Zoology really gets into their maneuverability and their power reserves. Can you lay out how these two aspects are linked? As I was reading the paper, I really kept thinking of hummingbirds in video game terms and imagining little meters at the top of the screen. Yeah. So a couple of questions motivated this study. And it was led by my colleague Paolo Segre and my co-author Doug Altshuler.

So one of the questions was when we're measuring their maneuvering performance, which includes lots of complex behaviors that have a lot of degrees of freedom, how tightly can they turn? How fast can they move when they're turning? How fast can they accelerate, decelerate? When we're measuring those maneuvers, it's really hard to capture what is a bird's maximum ability.

The more freedom you give them in a space where you're capturing what they do, the less well-defined maximum is because there's so many different ways to move in a completely open environment. So we've been studying maneuvering ability across different hummingbird species for some years.

But we wanted to know, is the power they're able to generate in a more constrained assay, like our load lifting assay, is it predictive of some maximum that we're able to capture in this free flight assay? That was the motivation for that study.

So led by Paolo, what Paolo did was he reasoned using fundamental physics that one of the basic maneuvers that they use very frequently to turn, which we're calling an arcing turn, which is basically just a level turn that if you look at it from above, it follows a smooth arc.

He reasoned that those arcing turns, that we can build a physical model of the forces that they need to produce those arcing turns.

And we can test whether the maximum load that a bird is able to lift in our load lifting assay, does that correspond with the maximum that they're hitting up against as they redirect forces during those arcing turns. So one of these arcing turns you're describing here, would this perhaps be one of these maneuvers we see when one hummingbird chases another hummingbird away from a feeder or flowers in our yard? Um,

Yes, absolutely. Yeah. And yeah, definitely they'll use arcing turns during chases. They'll also use arcing turns during obstacle avoidance, which is really important to a fast moving animal. Those collisions could be deadly.

Yeah, the collision avoidance turns, I guess I don't notice as much because if they're avoiding collision with my head, it's all happening so quickly. But sometimes we'll be watching them off and we'll be watching them and we'll see one chase the other off. And it sounds like that's what you're talking about here. Exactly. I'm sorry, but I got us off topic here. You were describing your analysis of these turns.

Right. Yeah. So in those free flight assays, we aren't telling the birds what to do. They're performing at a sort of routine flight level of performance as they're trying to avoid the threatening experimenters, avoid collisions with the sides of the flight chamber.

But we can capture thousands of maneuvers from each individual over a relatively short span of time because everything hummingbirds do just happens on a much faster time scale than other species or than their own lives. So if you record a hummingbird for two hours, you might capture 2,000 arcing turns, for example.

And so we can computationally pull out the segments of flight that represent the arcing turns that were limited to a level plane. And we can apply the physical model that Paolo built to say, okay, the redirection of forces as the bird is banking its body to execute that turn

What's the kind of space of what that looks like for the many, many thousands of turns that we captured from the different hummingbirds in our study? We studied about 20 individual hummingbirds in that study. And does the limit of that distribution, how does that align with our predicted limit from how much weight those birds could lift in our highly constrained load lifting assay?

And what we found was that overall, collectively, the model predicts really well the maximum turning performance of the birds in that chamber. So the Anna's hummingbirds that we study, they're from the west coast of North America, slightly larger species than we have here in Ottawa or where you are. But they have, in our loadlifting assay, they can lift about two and a half times their body weight.

on average. And we can model what that would translate to in terms of being able to redirect forces to execute that turn. And the birds in our free flight experiment, their peak performance matches that peak of what we would predict based on their maximum ability.

So it's really satisfying. It aligns with our hypothesis that in order to be maneuverable, that power has to come from their muscle capacity in flight and their kind of excess muscle capacity, their ability to just lift weights vertically is going to determine power.

how well they can execute these high-performance acrobatic maneuvers. So as they're flying about during the day, how often are they absolutely using up their power reserves? Yeah, that's a really good question that we don't know the answer to yet.

And how often are they hitting their maximum out in nature? Probably not that often compared to, you know, when you think of like the lifespan of a hummingbird and how much they do during the day.

I would estimate, I would hypothesize that it's pretty rare that they're executing maneuvers that are hitting their max. But in our flight chamber, you know, it was a pretty small proportion, maybe 1% of the turns are kind of hitting that maximum envelope. And maybe it's similar out in the wild, but that's something that we'll be able to test in the future, hopefully.

For example, by having sensors small enough to put on a really small bird. That's kind of the challenge there. But a lot of the time of the day, they spend perching. And probably one of the biggest challenges for them is maintaining the muscle mass that they would need to execute those rare, super high-performance maneuvers. That's absolutely fascinating.

When it's PCS time, you know the drill. Pack, research to new base, get the kids in school, because family supports family. At American Public University, we support military families with flexible, affordable online education that moves with you. As a military spouse, your tuition rate is the same as your partner's, just $250 per credit hour. American Public University, education that moves with you.

Learn more at apu.apus.edu slash military. This July 4th, celebrate freedom from spills, stains, and overpriced furniture with Anabay, the only machine washable sofa inside and out where designer quality meets budget friendly pricing. Sofa start at just $699, making it the perfect time to upgrade your space. Anabay is

pet friendly stain resistant and interchangeable slip covers are made with high performance fabric that's built for real life you'll love the cloud like comfort of hypoallergenic high resilience foam that never needs fluffing and a durable steel frame that stands the test of time with modular pieces you can rearrange anytime it's a

♪♪♪

Hey, good drivers. Yeah, we're talking to you. The ones who don't speed, the ones who avoid those fender benders, and who always use their turn signal. Congratulations, you're a better driver, and that means you could get better rates with Route Insurance. It's time to stop paying for other people's bad driving habits. You know, like the ones who cut you off just to slam on their brakes. Woo!

or the lead foot speeding to work every day. With Root Insurance, you'll get a quote based primarily on your driving. Just download the Root app, drive around like you normally would for a couple of weeks, and boom, you'll get a quote that actually makes sense. It's that easy. Root. Because better drivers deserve better rates. Download the Root app today and see how much you could save. That's Root Insurance. Terms and conditions apply. Subject to underwriting review. See Root.com for details.

So you want to start a business. You might think you need a team of people and fancy tech skills, but listen to me when I say you don't. You just need GoDaddy Arrow. I'm Walton Goggins, an actor, and I like the sound of starting my own business, Walton Goggins Goggle Glasses. But I couldn't do this on my own.

GoDaddy Arrow uses AI to create everything you need to grow a business. It'll make you a unique logo. It'll create a custom website. It'll write social posts for you and even set you up with a social media calendar. How cool is that? Well, listen to this.

For a limited time, you can get Aero All Access for just a dollar a week for 12 weeks. We're talking all the AI power of GoDaddy Aero plus a domain, e-commerce store, payments, professional email, a unified inbox, all for less money than I spend on deep tanning lotion while sunbathing off the Amalfi Coast. You know what that sounds like? A plan. Get started at GoDaddy.com. Terms apply. Now, I have another question or two about just studying the hummingbird. Like we...

as we observe them you know we we obviously pick up that they are they're very powerful creatures in their own right but we also get the sense of fragility about them are they are they fragile to deal with like what how is it different dealing with hummingbirds versus other birds you might be studying in your in your work yeah um i would say um

In the lab, they're relatively easy to deal with compared to other species. And part of that might be they're so specialized. If you kind of know the conditions they need, they're

relatively easy to keep healthy. The main point of fragility is that super high metabolic rate. If they run out of food, that's catastrophic. But if you've got the right conditions for them, kind of unlimited food, the right physical space, they're pretty easy to deal with in the lab.

But we have to house them separately. And that's different than other birds because, yeah, they're so aggressive. They would exclude each other from feeding, for example. And their bills can be a weapon. So when they're kind of housed in captivity, we keep each individual on its own.

And you don't see it that often in the wild, but, but if you, if you have video footage, high speed video footage of birds interacting and fighting at a feeder, you know,

you'll see how that bill is really like a long dagger and that they're, when they're facing off, they're making sure they orient their bills towards each other. And you can imagine a collision with those long bills would be really catastrophic for an animal that only weighs two and a half grams. Oh, wow. Yeah. That was going to be one of my questions. Like what, like what, what is the, we see them chasing each other. Like what are they actually doing to each other? If they catch it, it's kind of sounds like it's like a joust in a sense. Right.

Yeah. And it's really hard for us to capture what that, like, what are the consequences of that in the wild? The best examples we have are footage that people can capture at a feeder. And when birds really get into it close to a feeder, what happens? And you see them grabbing each other's feathers and using their bills to defend that space, to displace another bird. And, yeah.

And there's still a lot of open research questions about, you know, exactly how, like what signals or outcomes are determining who wins those competitions.

And that's an active area of work that we're studying now in my lab. But even in the lab, we'll see them rarely make physical contact with each other. So if one bird wants to displace another from a perch, sometimes they'll get into little scuffles where they're making contact. And I think at high speeds, those kinds of scuffles would be really dangerous to both individuals. So that's a real game of chicken.

Now, when you're studying hummingbirds, is it completely seasonal? Is seasonal availability very much a part of this, or do you have hummingbirds in captivity that you can study year-round?

Yeah, so in my lab here in Ottawa, we're studying ruby-throated hummingbirds and they are migratory. And so we've been catching birds here since the beginning of May and we've got a group of males in the lab now that will release again prior to their autumn southward migration. So we're only working with them within the breeding season here and only studying the males.

And remarkably, many individuals, many of the migratory species, an individual hummingbird will come back to the very same feeder. So one of the birds in my lab now is a bird that we caught and released on campus last year, attached a little band to his leg with an identifying number.

And he would have migrated all the way to Mexico. And then this spring, the first two weeks of May, like clockwork, he showed up at the exact same feeder. We captured him again this year. So it really is remarkable, not only the physical feats that they do, but also the

They have remarkable memories. And so they're and that's all part of their high metabolic rate. They need to know where those reliable food sources are. So this male ruby-throated hummingbird came back to the exact same feeder after this cross-continental journey. That was going to be one of my follow-up questions about what's going on in the mind of a hummingbird. Because, again, they're such drastically different creatures.

They're living on this time frame that's so different from ours. And then vast distances in addition to vast speeds. So what else do we know about the way their little brains work? Yeah, it's really fascinating. So there's a lot of excellent research coming out of my co-author, Doug Altshuler's lab on how their brains work and how the visual system works. And we also have studies of their brain

spatial memory. And so a really beautiful study from about 20 years ago now on a species of hummingbird that lives in the Rocky Mountains looked at their ability to learn flowers that change in nectar availability through time. So real flowers are not like feeders. Real flowers will be depleted and will replenish themselves over some seasonal period.

And hummingbirds that have a territory with lots of flowers in them, they need to know where their next meal is coming from. And they're able to learn the locations of many flowers. As an example, this bird that came all the way back to my feeder from Mexico, he would have remembered other places along that route, we hypothesize. So what the researchers did in Alberta, Canada, was...

create an experiment where they could track one male in the wild who had a territory and they had dynamic feeders in that territory that went on different time schedules. Maybe some feeders would replenish on five minute intervals, others on 10 minute intervals, others on 20 minute intervals. And if a, if a bird had multiple of those variable timed feeders available, would they be able to learn those different time schedules?

And they found that indeed they could. So not only can they remember where the food resources are, but they can keep track of multiple variable schedules within their territory, like all in their head, right? So they've got like a calendar in their head to determine which resources have food, where are they, and when are they going to become profitable again?

Um, and, and their brains are really, really small. Remember, cause their, their whole bodies are miniaturized. So their brains are much, much smaller than the brains of other birds. Um, so it's really quite incredible that they can do that. Yeah. I'm really impressed by their ability to map all that out. And then I feel a little, I can't help but feel guilty because

by how, like if I forget to refill the feeder or to change out the nectar in a feeder, now I'm going to feel even worse because I'm messing with their finely tuned mental map of where all the flowers in the feeders are. Yeah.

It is important. If you're maintaining a feeder, it's important to keep it going. But they're really resilient as well. They've been around for millions of years before we started providing feeders.

And, uh, and so the birds that are in your, your yard there and in your neighborhood, they're going to have other food sources mapped out. Um, so yeah, it's, it's important, but, uh, it, it's unlikely to be catastrophic if one person, you know, forgets to refill their feeder. Um, but what's also fascinating is that we're learning how those feeders are changing, are causing contemporary evolution in hummingbirds. Um,

The species that we have on the eastern North America here, ruby-throated hummingbirds, their populations are doing quite well despite lots of threats that humans are creating for other bird species. And probably a big part of that is humans providing food to them. On the west coast, the Anna's hummingbird is a species that has expanded its range. So it used to only live in kind of

warmer states in the southwest of the U.S. And now we find that species Anis hummingbird as far north as Vancouver, Canada, where we conducted our research. They've expanded over the past century with people providing food, both ornamental flowers, but also feeders. And we're learning that there's a study that just came out this year. We're learning how

providing feeders is causing measurable changes to the morphology of their beaks. Their beaks are changing in size as they've been expanding. So it's really, really neat because beak shape evolution is kind of this classic case that led Darwin to come to appreciate how natural selection works. And we humans are now causing that to happen on a rapid timescale.

Wow. So what sort of changes are taking place here? Are the beaks getting shorter, longer? Yeah. So their beaks are getting longer to be able to extract food from feeders. And the way researchers have been able to discover that is by measuring the beaks of museum specimens that were collected over the past century and kind of building up a time series of specimens from 100 years ago, 50 years ago to present. Wow. That's impressive.

So you're spending all this time studying hummingbirds. Do they retain their magic for you or do they become like just a little every day? Are they still exciting? They are still exciting. One of my favorite moments from going out into the field at the sites where we find our hummingbirds is getting to see courtship displays, getting to see a male court a female courtship.

And the ruby-throated hummingbirds, they do the shuttle display where they're zooming back and forth and they start with a small arc and they're flaring their colorful feathers in front of the female and their shuttle gets bigger and bigger, faster and faster. It's still really magical even after handling lots of hummingbirds in the lab. And the other thing I find really exciting about them is seeing their behavior slow down. If you capture...

with high-speed video and then watch them at slow speed, it really looks like you get an even greater appreciation for what they can do because it looks like they're swimming in the air. It looks like they're moving in the air as deftly as we do swimming.

kind of on the ground and you get a real impression for things that they can do that, you know, they just whiz by you when you're seeing it in real life. But there's a lot happening there. Yeah, I know just from this was several years back, but I went with my family to Costa Rica and we got to see some hummingbirds there and some feeders. And just with whatever sort of iPhone we had at the time,

You know, you could take a pretty decent video and slow it down and get this enhanced appreciation for what they were doing. And so I can only imagine what's possible, A, with today's iPhones and smartphones and with like serious film equipment.

Yeah, yeah, that's right. And Costa Rica has a huge diversity of species and different locations that you'll visit will have different species. And that's another question that continues to fascinate me. The smallest hummingbirds we have are just two grams, which is the mass of a penny. And then the largest species we have is 20 grams. That's 10 times bigger.

Um, and then we've got 366 species that span that range. Um, most of them kind of between the two to 10 gram size, which is still a big, a big range. Why is it that there's so many different ways to be a hummingbird? How do all of these, like this, this one kind of overall strategy, how does it lead to this diversification and how do they all coexist is another really fascinating question. All right. Well, Rosalind, thanks for coming on the show and chatting with me today about hummingbirds.

Thank you very much. Thanks once again to Rosalind Dakin for taking time out of her day to chat with me. Again, the paper is Turning Tradeoffs. Hummingbird power reserves are used to decrease turning radius or increase turning velocity out now in the Journal of Zoology. And you can learn more about her work with the Dynamic Behavior Lab by visiting her website at rosalindakin.com. That's R-O-S-L-Y-N-D-A-K-I-N.com.

Just a reminder to everyone out there that Stuff to Blow Your Mind is primarily a science and culture podcast with core episodes on Tuesdays and Thursdays. But on Fridays, we set aside most serious concerns to just talk about a weird film on Weird House Cinema. Thanks, as always, to the excellent J.J. Possway for producing the show. And if you would like to reach out to us, you can email us at contact at stufftoblowyourmind.com.

Stuff to Blow Your Mind is a production of iHeartRadio. For more podcasts from iHeartRadio, visit the iHeartRadio app. Apple Podcasts are wherever you listen to your favorite shows.

When you're part of a military family, you understand sacrifice and support. At American Public University, we honor your dedication by extending our military tuition savings to your extended family. Parents, spouses, legal partners, siblings, and dependents all qualify for APU's preferred military rate of just $250 per credit hour for undergraduate and master's level programs.

American Public University. Value for the whole family. Learn more at apu.apus.edu slash military.

This July 4th, celebrate freedom from spills, stains, and overpriced furniture with Anabay, the only machine-washable sofa inside and out where designer quality meets budget-friendly pricing. Sofas start at just $699, making it the perfect time to upgrade your space. Anabay's pet-friendly, stain-resistant, and interchangeable slipcovers are made with high-performance fabric that's built for real life. You'll love the cloud-like comfort of hypoallergenic,

We'll be right back.

declare independence from dirty, outdated furniture. Shop now at washablesofas.com. Offers are subject to change and certain restrictions may apply. Toyota is the best resale value brand for 2025, according to Kelly Blue Book's kbb.com. And with a wide range of dependable vehicles for any lifestyle

You can get everything you need in a vehicle today while investing in tomorrow. So choose Toyota and choose value. Shop buyatoyota.com for great deals and more. Vehicles projected resale value is specific to the 2025 model year. For more information, visit kellybluebookskbb.com. Kelly Blue Book is a registered trademark of Kelly Blue Book Co. Inc. Toyota, let's go places.

Career changers, including veterans and active duty service members. Your transition starts here. Go from GI to IT in a matter of months. Become a certified cyber warrior with training at My Computer Career. Cyber security specialists are in high demand, offering IT pros great opportunities and a rewarding lifestyle while protecting our people, liberty, and treasured institutions from cyber threats.

Deploy your career in IT today. Learn more at mycomputercareer.edu. SkillBridge and other VA benefits are available to those who qualify. This is an iHeart Podcast.