In this episode, you’ll hear about:

• How birds see a whole extra dimension of color (including UV) and why we can’t truly experience “bird vision” without the biology to match

• How feathers make color through pigments and nano-structures

• How studying bird color is changing fast, from spectrophotometers to UV-capable cameras, plus why female coloration and “dirty birds” are reshaping what we think we know

• 00:08 - The Vibrant Kitinga

• 02:25 - Understanding Bird Vision and Color Communication

• 10:11 - Understanding Bird Coloration: Pigments and Structure

• 19:30 - The Impact of Urban Environments on Bird Coloration

• 29:54 - Debunking Bird Myths

Timestamp Disclosure
These timestamps were generated using AI and may contain errors or omissions. They are provided for accessibility and reference purposes only and may not perfectly reflect the original audio.

Dr. Allison Shultz (Excerpt)
It's hard to beat a Kitinga for just bright, vibrant plumage. Their feathers were highly sought after by Victorian fly tires. Yeah, but we have some in our collection.

And every time I open that drawer, people are like, what? That's a bird? That's real. Yes, it is real. It's amazing.

Dr. Scott Taylor
Seeing a new species of bird is always exciting, but it doesn't always make my brain short circuit. Sometimes, though, it does. And those moments really stick with you.

It was my first time in the Amazon rainforest, which is already an overwhelming place to be. The heat, the songs and calls from birds, insects and mammals.

We were deep in rainforest green, floating along the Tipitini river inside Yasuni national park in Ecuador, surrounded by that green that feels like a has its own humidity setting. Everything is dripping, everything is loud. And then up in the canopy along the river's edge, we spot it. A plum throated ktinga.

Just sitting there like it knows it's the main character. This unreal saturated punch of color against all of that green foliage. It was truly astounding. One of those birds that makes you whisper, no way.

And here's the part that messed me up. That bird, that jaw dropping color I could barely process, was only the human version of the message. Because bird vision isn't just more color.

It's a different visual operating system.

And the cool thing is, scientists didn't even realize that until the 1970s, when researchers started running simple but mind bending experiments, training birds to tell the difference between lights that looked identical to humans. Only to find the birds consistently saw the ultraviolet option. That discovery basically opened our eyes to an invisible layer of bird communication.

No pun intended. And it changed how we understand plumage forever.

On top of their ability to see in the ultraviolet spectrum, bird eyes also have built in filters called oil droplets that can sharpen how they separate colors.

Like nature installed a higher end lens on the same camera body, Many species also pick up cues we barely register, like finer motion detail and faster flicker. Because they have two to five times the number of cells in their eyes that function during the daytime.

So when two birds look at each other, they're not just seeing prettier, they're seeing more information, more contrast, more signal, more meaning. Which brings us to today's episode. Okay, but why is a bird's world more colorful?

To help answer that question, we're joined by Dr. Allison Schulz, Associate creator of ornithology at the Natural History Museum of Los Angeles County. Allison studies the evolution of bird color and bird vision, which is perfect for our topic.

Today because she thinks about plumage the way birds use it. Because feather color isn't just a simple sick paint job. Sometimes it's pigments, actual molecules laid into feathers.

Sometimes it's structure, tiny microscopic architecture that bends and bounces light to create those impossible blues and iridescent shifts that feel like special effects. Sometimes it's both stacked together, like the bird said. I'm going to do the most.

Think blue footed booby feet, which are aquamarine in color from combining structural blue with pigment that is yellow. And then the vision side comes in and the whole thing clicks. A color patch isn't just there to look nice, it's there to be ready.

It's a signal tuned to the viewer's eyes in the background light of that environment. A bright, open habitat plays by different rules than a dark forest understory.

What pops in one place can disappear in another, which means the same feather can be a billboard or camouflage, depending on where you stand. So today we're going to talk about what bird vision really is beyond more colors.

What wavelengths birds see that we don't, what their eyes are optimized for and why that matters for communication and survival. We'll get into where feather color comes from. Pigments versus structure. And the surprising moments where human intuition is totally wrong.

Because if birds are using color as language, what happens when we change the lighting, the habitat, and the background noise of their entire visual system? Think pollution, diet changes and habitat shifts that change. What good signaling even looks like.

After the break, Alison Schultz helps us see what birds see, how their colors are built, and why that plum torto katinka in the Amazon was almost certainly broadcasting a message I could only partially understand. Stick around. Well, welcome back, everyone. I'm super excited to have Dr. Allison Schultz with us. Thanks for joining us, Allison.

Dr. Allison Shultz
Thanks so much for having me on here, Scott. It's really a pleasure.

Dr. Scott Taylor
Well, I'm admiring the birds behind you and excited to talk about all the amazing colors that they are and that they can see. And I thought we could start off first just by talking about what can birds see that we can't see? And why does that matter?

Dr. Allison Shultz
What really got me into studying birds, I think was just literally appreciating their beauty.

I actually went to a talk last week on the Science of Awe, which I hadn't ever really thought about, but it really stuck in my mind that actually, that's like awe is just what I experience when I look at birds and I go in the collection and look at their beautiful colors.

And so one thing that really got me thinking when I first took Odor anthology and I saw these beautiful birds was like, how are they seeing each other? And so it ended up being the topic of my master's dissertation. And really, birds can see not just what we can see, but they can see even more.

So they can see. As humans, we have three types of cones in our eyes. Roughly short wavelength, medium wavelength, long wavelength.

Think like, RGB color space, red, green, blue. But birds have a fourth type of cone, and that fourth type of cone extends down to about 300 nanometers, so it sees ultraviolet color.

So they can see not just more colors than we can, but because they have four cones instead of three cones, they can combine them in different ways. That essentially gives them a whole nother dimension of color.

So, you know, a common question that I get asked all the time when I give talks to the public is, can I make bird goggles? I want to see like a bird can see.

Dr. Scott Taylor
That would be amazing.

Dr. Allison Shultz
We just can't because our brains aren't set up to see a whole nother dimension of color.

Dr. Scott Taylor
I've never thought of that one. I like the awe factor. And like the science of awe, I really. That really resonates.

So, yeah, I always think about, in the context of, like, their ability to see in the uv. I think of European starlings, which most people are like, oh, starlings are boring.

But if you saw a starling the way starlings see each other, I mean, they're. They're spectacular creatures.

As far as we can kind of model it and understand in terms of bird communication and coloration, then, you know, they live in this kind of other color dimension. But how does that shape their evolution or what patterns do you find really interesting in that context?

Dr. Allison Shultz
There.

There's kind of been this idea for a long time that because birds can see uv, that maybe UV is like a special channel of communication, and that birds can then see these colors. Maybe these colors are combining, and there'll be a bright patch that they can see that mammals can't.

You know, mammals are a predator of birds, Although many birds are also predators of birds. Of course.

Dr. Scott Taylor
Yeah.

Dr. Allison Shultz
Seeing ultraviolet and having more types of cones is actually the ancestral state. So many fishes actually have more than four types of cones. You know, reptiles, amphibians, lizards, also can see UV colors.

So it's actually just that we are almost. I don't want to say impaired, because we're just like. We just have lost the ability to see this. This wonderful realm of colors.

But from a biologist point of view, that means that when I'm studying how colors evolve. I really need to consider colors not from how humans see them, but colors from how birds see them.

We need to think about color either as measured with what's called a reflectance spectrophotometer, which is an unbiased way to see how much light is being reflected at each different wavelength, or color as modeled by the avian visual system as best we can, which includes those extended wavelengths and a couple other features of color that I really haven't talked about yet.

Dr. Scott Taylor
Yeah, talk a little bit more about that. I mean, the unbiased way of measuring color is really interesting historically.

Like, if people were trying to quantify color differences between different kinds of warblers, or like in your case, different kinds of tanagers, which was a large part of your research, they would just look in a field guide and like, grade, oh, this patch is this color, this patch is this color. But contemporarily, we don't really do that anymore. If we can get our hands on feathers and. And then these spectrophotometers.

Could you walk us through how you do that?

Dr. Allison Shultz
Absolutely, yeah. So I have other device that. It's got a probe. You know, I should have taken it out so I could actually just show it to you.

Dr. Scott Taylor
But they're so delicate, though, I would be afraid of it breaking.

Dr. Allison Shultz
Yeah, it's this little box that's about this big and it plugs into my computer. And basically there's another little box that's a source of light. So this is a. Basically it's a device that's going to shoot light out of a portal.

And that portal is attached to a fiber optic probe. So the light goes down the fiber optic probe. At the end of the fiber optic probe I have. It's the specimen or whatever I want to measure.

So some feathers, the bird that light shoots back into the fiber optic probe and then into the spectrometer that's connected to my computer. Essentially, I'm just controlling very precisely the light that gets reflected out.

And then I know what's reflected back in and I do it via a standard. So something that I know the reflectance of. And so because of that, we can actually get pretty accurate measurements.

There's also we could use photography. So that's another method that's becoming more and more popular.

You actually use a regular camera, but you strip off the coating of the lens that's protecting the camera from uv, and then you have to get another special lens that will actually allow the sensors to capture uv. You know, there's kind of a few different methods that have pros and cons, but really a spectrotometer and then a camera are the main ones.

Dr. Scott Taylor
And then in terms of those colors that you're measuring, could you talk a little bit about all the different ways that birds produce color?

Because I think not a lot of people realize how much variation there is, and that there's really specific colors associated with either structure or pigment or whatever.

Dr. Allison Shultz
Yeah. So there's.

This is probably one of my very favorite topics, which is not just why are birds the colors that they are and what are those colors, but how are birds the colors that they are? So there's kind of two main ways that birds are the colors that they are. One is pigments.

So pigments are essentially chemicals that birds can put into their feathers that absorb certain wavelengths of light. The two main ones are melanin, which produces browns and blacks. It's the same pigment that colors our hair and our skin.

And then carotenoids, which are. Think carrots. You know, that's in the realm of carotenoids that produce yellows, oranges, and reds.

And so that's how you get from the rainbow from red, essentially, to yellow.

And then to go into greens and blues and violets, then you have to have what's called structural color, which is basically the little nanoscale structure inside of the feather. There are these pockets of air and keratin. Keratin is what feathers are made out of, just like our fingernails.

Light is going to refract off of the keratin depending on exactly what that structure is and is going to. So certain wavelengths of light are going to reflect off of that. So that's how you get those shorter wavelength colors like blues. Interesting.

Greens, which is my very favorite, is a combination usually of yellow pigment and blue feather structure. So think about finger paints. You mix them together, yellows and blues, you get green. Except for the turraco, which is my favorite.

Dr. Scott Taylor
The turaco.

Dr. Allison Shultz
The turacco. I love turacos. Yes.

Dr. Scott Taylor
Yeah. I mean. Yeah. Tell us why. I mean, the green of the terraco is this special, special thing, right?

Dr. Allison Shultz
It is, yeah. So it's basically.

Well, I say the only green pigment with an asterisk because it turns out that the green of jacana wings, as well as the green in the rural, which is a type of pheasant, it's actually probably the same pigment as turacos have.

Dr. Scott Taylor
Oh, really?

Dr. Allison Shultz
Yeah.

Dr. Scott Taylor
I did not know that. That's cool.

Dr. Allison Shultz
As well as eiders have this really, you Know, the green on an eider neck is also a very unusual. Its own green pigment. Anyway.

It's actually a green pigment that's very similar in structure to hemoglobin in our blood, but instead of iron, they have copper in the middle. So what color is oxidized copper? It's.

Dr. Scott Taylor
Yeah. Pretty greenish.

Dr. Allison Shultz
It's green.

Dr. Scott Taylor
Yeah.

Dr. Allison Shultz
Yeah, exactly.

Dr. Scott Taylor
Oh, that's so cool.

Dr. Allison Shultz
So their own special form of green. And it's actually the birds that got me started studying color. I really wanted to study Turoco's. I wrote my GRFP proposal on studying Tiroco.

Someday I will study Tiroco.

Dr. Scott Taylor
Someday you will.

Dr. Allison Shultz
Someday I will.

Dr. Scott Taylor
I like those someday I will studies especially. I mean, studying chiracos would be so cool. They are really awesome birds. Really beautiful colors.

But, yeah, I think it's interesting and it's hard for people to think about the fact that there are no, like, the blue birds. We see the ones that we're really familiar with, blue jays and actual bluebirds, eastern, western, or mountain.

If you take their feathers and you shine light through them and you look from the other side, they're gray, they're not blue. But it's hard until you're holding one and looking at it to really realize that that's all reflectance and not an actual pigment, but super cool.

Dr. Allison Shultz
Exactly. Yeah.

I like to say if you were to grind up the feather of a bluebird, you know, the powder would be kind of grayish brown because you're destroying that structure.

If you were to grind up the feather of a yellow bird or red bird, like a cardinal or something like that, the powder would be red because the carotenoids are still intact.

Dr. Scott Taylor
There was a recent paper.

Well, I don't know how recent it is now, but the paper about budgie coloration, or parakeet coloration, where, you know, you have the blue ones that are blue and white, and then you have the wild type ones that are yellow and green, and the blue ones, they just don't have ability to deposit carotenoids. So everywhere that would have been yellow is now white, and everywhere that would have been green is now blue.

And it's neat to think about how you can play around with those toggles in the kind of broader evolutionary framework of birds as well.

Dr. Allison Shultz
Totally. Yeah.

And those, you know, domesticated, while domesticated species, like budgies or, you know, some of the other parrots in captivity, it's because they break some of those pathways to having certain colors that we actually can learn about the genetics of how those colors come to be.

Because you can actually do some like, experimental design or you can sequence, you know, individuals that have certain color patterns and, you know, actually figure out what are the genes responsible for some of these things. Which is pretty cool.

Dr. Scott Taylor
Yeah. Because carotenoids are complicated.

You have to eat them and then either just take what you've eaten and put it in a feather or take what you've eaten, turn it red and put it in a feather. Because usually like the consumed carotenoids are typically yellow, Right?

Dr. Allison Shultz
Correct. Or take what you eat and turn it a different color yellow and put it in your. Yeah. Or put it in your eyes.

Dr. Scott Taylor
Yeah. Oh, yeah.

Dr. Allison Shultz
Or keep it in your blood. Yeah, yeah.

Dr. Scott Taylor
You gotta move it around. You need to like put it in fat soluble molecules, get it into wherever you need it.

And yeah, it's good to point out too, birds aren't just feather colorful. There's a lot of birds that have really colorful skin. Maybe just think of like a chicken and its colorful comb that's also pigmented.

Dr. Allison Shultz
Exactly. Coming back to visual systems, we talked about them having those four types of cones. Right.

So again, each of the long, the medium and the short wavelength cones also have little carotenoid filters on the cone. That's cool. That essentially makes them much more specific in what light activates them.

And so carotenoids are an important feature of vision for all birds. We know all birds can, can produce carotenoids and circulate them and metabolism, because they all have this visual capabilities, just pretty cool.

Dr. Scott Taylor
And they're little, little oil droplets, right. Like associated with the cones, that kind of fine tune color.

And yeah, I guess even turtles and some of these other reptiles have some of those tuning colors in their eyes as well, which is this ancestral state that mammals unfortunately have lost. Which makes me kind of sad about the colors I see in the world and how much cooler it could be.

Dr. Allison Shultz
I know, just imagine.

Dr. Scott Taylor
Do we know more about the colors we're missing with respect to female bird coloration in general? Have there been any advances in kind of understanding that aspect of bird vision?

Dr. Allison Shultz
There's like, there are one or two species where you look at a patch and it looks gray, but maybe it has UV in it.

One of my favorites, the palm tanager, which you, if you ever go to, you know, Central and South America, palm tanagers is one of the birds you'll see in the city and look kind of bland, kind of grayish, maybe tiny bit yellowish, but actually very reflective in the uv. But there are very few cases of like hidden UV patterning. I won't say there's none because there's like one or two, but very few.

That said, how many people have actually, like, looked at all female birds with a camera or a spectrometer to, like, see if there are hidden signals?

Dr. Scott Taylor
I wouldn't be surprised if they didn't. I mean, when you open a typical drawer at a museum, it's full of the really colorful males. And typically females are underrepresented, right?

Dr. Allison Shultz
Absolutely. Yeah, there was a paper documenting that very thing.

And so there's definitely a bias in the literature towards studying male plumage and male coloration. Many, many fewer papers have studied female coloration and how colors are made.

And so that's actually one of the goals for my research, is to, you know, add that female color perspective and maybe even focus on that sometimes.

Dr. Scott Taylor
In the environment perspective.

What have we learned about the light in a habitat and how that changes which colors work best, like open spaces versus forests, and like, what you could predict from seeing a bird in terms of where it might live based on coloration. Are there broader patterns there or. No.

Dr. Allison Shultz
The broadest pattern that's been found over and over again is that birds that tend to live in closed habitats. So think like in forests, basically, areas that are protected from the sun tend to be darker in color.

So understory birds or forested birds compared to birds that live in open habitats. Also, the wavelengths of light in these different habitats can be different as well.

So, for example, in a forest environment, a blue actually might stand out a lot more than a red just because of the wavelengths of light that are there. And so, you know, what you might expect actually depends on what you think the birds want to do.

Do they want to stand out or do they want to blend in?

Dr. Scott Taylor
Totally. I always think about in that context, like birds of paradise males have these feather elaborations.

They have insane behaviors along with really, really amazing colors, often flashes of color. Whereas the females are more camouflaged, and they're the ones that lay the eggs, take care of the chicks. The males don't help.

So it makes sense that evolution would favor this elaborate coloration. I think my favorite thing about the birds of paradise was we watch them from our perspective as people.

But once you actually position yourself to watch a bird of paradise during its display, like a female bird of paradise would, it becomes much more colorful.

Dr. Allison Shultz
Absolutely. And you know what I can't wait for is when people actually look at the neurology of birds, like, how do birds brains work?

You know, we've studied a lot about, like, their eyes. We're now thinking about their behaviors, but how are their brains processing color? That's like something we don't know at all.

Dr. Scott Taylor
Your current research is kind of looking into this, like, human impacts on coloration in birds. Could you talk a little bit about what people have been finding? What are the big stressors that you find interesting or studying right now?

Dr. Allison Shultz
What I specifically am thinking a lot about, I think a lot about urban environments. And there's been a few cool papers looking at how urban environments might filter birds. So, like, more there.

There's actually some paper showing that more colorful birds tend to live in cities, which is very interesting. What I'm studying right now is actually pollution and how pollution shapes birds phenotypes.

And so if birds are exposed to pollutants like heavy metals or they don't have as rich diets or things like that, you can imagine that their colors might be less vibrant just because color is often tied to bird health. So it's an indicator of how healthy birds are. But then in a much simpler way, pollution actually can lay on top of colors and block them.

So, for example, I'm a museum curator. I work in museum collections. When I first got here, I was looking at drawers of house finches because I studied house finches for my dissertation.

And I noted that some of our house finches were black. And even the red, I could tell that they were males and that they had red, but it's covered in black.

So it's completely like almost completely blocking out that signal.

Dr. Scott Taylor
Wow.

Dr. Allison Shultz
And right around the time that I started, Shane Dube and Carl Fuldner had come out with this paper in the Chicago area showing that actually how dirty bird specimens are tracks major world events and is probably a good proxy for levels of air pollution. I've now since jumped into that realm. So it really opens up a few different avenues.

One is using museum specimens to measure air pollution levels through space and time. In times when we actually, as humans, we didn't record it.

But I'm also thinking about what does the air pollution do to the birds, how well feathers can absorb or reflect heat, which is a whole nother physiological constraint. Carbon is known to absorb more heat.

And so I had a postbac, Melissa Gonzalez, who was working with me last year on these dirty birds with our infrared spectrophotometer.

We have another spectrophotometer now, working with me and my collaborator, Terry McGlynn, to say, does having a bunch of carbon not only change the colors that you are visually, but also change how much heat you are absorbing? And we're writing up this paper now, but the short answer is yes.

So if you're a pale color, like white or, say, yellow or something like that, and you're covered in carbon because you're really dirty, you're exposed to pollution, you actually, your feathers are absorbing a lot more heat than they would otherwise, which is pretty interesting.

Dr. Scott Taylor
Yeah. And potentially exacerbating ongoing changes in how hot places get and the frequency of heat waves and stuff like that.

Dr. Allison Shultz
Exactly.

Dr. Scott Taylor
I think it's hard to comprehend how much of an impact humans are having and have had on the environment.

But then, yeah, just thinking about carbon deposition on feathers and that that can influence both the way birds perceive each other, but also their ability to thermal regulate is. That's incredible.

Dr. Allison Shultz
I mean, that's like outside of the light environment that cities produce, which can alter, you know, the visual way birds can see each other too. There's so many different aspects, and it's. Yeah, like you said, it's kind of bonkers to think about how they all interact with each other.

Dr. Scott Taylor
Where's your research program going in terms of bird color? Like, what's the most exciting part?

Dr. Allison Shultz
What I'm thinking a lot about now is how other aspects of feather morphology. So we've talked a lot about nanostructure and how that produces structural color. We've talked about pigments.

But something I'm really excited about is how feather barbs. So if we have a feather, you could think about the central shaft. That's what we call the rachis of the feather.

Branching off of that are feather barbs. Think of like the branches of a tree. And branching off of that even smaller are feather barbules. Think like twigs in a branch, for example.

And so we're learning that actually the shapes of these barbs and these barbules actually also can have really big impacts on colors. They can change how bright colors are.

They can change how rich and saturated colors are, even to some extent, change hue, although that's more tuned by some of those. The deeper coloration mechanism, like pigments and the structural colors.

So I'm excited about thinking about how these mechanisms all add up to each other to produce this one phenotype that we call color that's made up of all of these different things on top of each other, even the color of the feathers that lay on top of each other.

I don't know if you saw our paper led by Rosalind Price Waldman in Science Advances, where we found something that makes a lot of sense, but nobody's ever thought about it, which is that birds actually have, in some species, some of the brightest colored birds have an under layer that changes the color of light. So again, let's think about the structure of a feather.

So if I have a feather in my hand, the base that's closest to the bird is often kind of gray and very fluffy. That's the downy part of the feather. Whereas the tips will would be very colorful. So that's where most of the color is in the feather.

And so in many birds, we've only ever thought about the gray downy part and the colorful tips. But in tanagers is what we studied them in. But we actually have found them in many different types of songbirds.

We found that there is an in between layer that's white if you're colored by pigments, or black if you're colored by structural color.

And so if you think about how feathers lay on top of each other, they're kind of like tiles on a roof in that those tips are then laying on top of that white or black, you know, hidden layer.

And the effect of that white is that it's allowing those structures, those pigmentary colors, so those oranges and yellows and reds to be much brighter because more light is being reflected through those pigments.

And the black, those structural colors are actually much richer and more saturated because it's absorbing all of the wavelengths of light that are not being scattered by those nanostructures. So what's even really cooler is that in many of these Tengara tanagers, the males are colorful and the females are also pretty colorful.

They have the same patterns, but they're a little bit duller. And actually, it's entirely caused by the females not having that intermediate hidden layer like we actually looked at.

The color in the tips themselves is the same. It's just they don't have that extra white or black layer.

So that's causing sexual dichromatism or the differences between males and females in those species.

Dr. Scott Taylor
That's fascinating. Yeah, that's very cool.

That was very like just thinking about how that's how you could have differences between males and females just by varying the actual underlying color and not the actual color itself.

From a, I guess a biochemical perspective makes sense, really, because you'd have to alter pathways pretty considerably to either be green or not be green. But if you can just play around with the base layer and that makes you a little less vibrant, that's super cool. Yeah.

In your opinion, what three birds are kind of the best example of The, I don't know, vibrancy of color in nature. Our YouTube and Spotify visitors will get to see the examples as we talk. But for audio only, listeners, describe those three species as best you can.

Dr. Allison Shultz
If I were to just name species, I would probably pick three birds of paradise. Because birds of paradise have the fanciest plumages, the fanciest feathers, the fanciest dances that go along with that.

Their feathers are even the fanciest when you start looking them at the microscopic level. So it's hard to pick just one.

But king bird of paradise, they have these little green tails where the tail feathers are these long wires with little swirly bits on the very bottom. And they look. It's just amazing that a feather could grow like that. To me.

Dr. Scott Taylor
Yeah.

Dr. Allison Shultz
As well as having, you know, these really beautiful red breast feathers and these yellow black feathers and they're. We don't, we can't see this in our specimens because skin colors dehydrate, but their legs are a bright blue, which I think is just super cool.

We'll do something in the Americas. How about. I'm gonna have to go with, we'll say the lovely kitinga. It's hard to beat a kitinga for just bright, vibrant plumage these birds have.

You know, they're beautiful. Their back almost looks like an electric blue. Right. And they've got these beautiful purple breasts on them. And I, you know, they're.

Their feathers were highly sought after by Victorian fly tyers for. They're like one of the species that they used to use for. For tying flies. One of the species that people have stolen from museums over the years, so.

Dr. Scott Taylor
Oh, yeah, the feather thief, right?

Dr. Allison Shultz
Yeah, exactly.

Dr. Scott Taylor
It's a good book. It's a good book. I know someone who wants to turn it into a movie, actually, which I think I would watch.

Dr. Allison Shultz
Yeah.

Dr. Scott Taylor
Yeah.

Dr. Allison Shultz
Well, we have some in our collection and every time I open that drawer, I mean, that's one species of katinga. But any of the ones that are closely related are just like, it's just people are like, what? That's a bird that's real. It's like, yes, it is real.

It's amazing.

Dr. Scott Taylor
So, yeah, the first time I ever saw a plum throated kitinga in the wild, I was just dumbfounded. Like that that color could exist. Okay, then how about you choose your favorite tanager from a color perspective?

Dr. Allison Shultz
My favorite tanager, I mean, so that was probably gonna be the paradise tanager, which is pretty amazing. You know, it's got a good, a nice patch of each different color that you want.

So you've got your beautiful green head, you've got your red rump, your beautiful blue, and, you know, violet throat and blue belly.

And, of course, the black is this amazing super black plumage that is black, not just because of the melanin and the pigments, but because of the way the barbs and the barbules are absorbing extra light. Very similar to vantablack paint, but we, you know, not covered by a patent that doesn't allow anyone else to use it. Birds did it first.

Dr. Scott Taylor
Birds did it first. We didn't talk about super black.

Dr. Allison Shultz
I know. I was like, oh, we didn't talk about super black, but, you know, it's super cool.

Dr. Scott Taylor
Now. Now we have.

Dr. Allison Shultz
Now we have.

Dr. Scott Taylor
Yeah.

All right, we've reached the part of the show that we call that's BS or that's bird stuff, where we give our guests an opportunity to debunk a myth that ruffles their feathers. So, Alison, what do you want to call BS On?

Dr. Allison Shultz
I will call BS on some birds glowing in the dark. So.

Dr. Scott Taylor
Okay, that's a good one.

Dr. Allison Shultz
Yes. You know, so, yes, birds. Some birds have fluorescent pigments.

So if you shine a black light at the wing of an owl, for example, they have got a pigment called porphyryns that's going to glow pink. And that's true of, you know, some other kind of nighttime birds. And so a lot of people are like, these birds glow in the dark. That's amazing.

But what people forget is you have to think about the context. What is fluorescence? It's actually taking wavelengths of light of one color and shifting them to be another color.

In this case, it's taking ultraviolet color, wavelengths of light and shifting it into longer wavelengths of light, taking UV color and making it pink.

And what's important to remember is that there's, like, not a lot of UV light at night when the, you know, and actually our eyes see pink the same way that these bird's eyes see pink. So the fact that we're not walking around seeing glowing pink owls means that other birds are not also walking. You know, they're not flying.

Seeing glowing owls. In fact, it's potentially actually a means of camouflage because.

But, you know, the owls are taking UV light, maybe say, moonlight, and changing it to something that's much less prevalent. So there actually might be even darker to their prey in the dark. So it might actually be camouflaged to them.

Dr. Scott Taylor
Oh, cool. I didn't know about the camouflage piece, but, yeah, it's the same as you can go looking for scorpions with ultraviolet light.

But in the absence of ultraviolet light, a scorpion isn't running around a little green thing.

Dr. Allison Shultz
Exactly.

Dr. Scott Taylor
On the ground.

Dr. Allison Shultz
Have their UV flashlights that they're using to, like, look at each other.

Dr. Scott Taylor
Yeah. Yeah. But I've definitely seen that in the popular press that, you know, owls glow at night. So thank you for debunking that.

Dr. Allison Shultz
My pleasure.

Dr. Scott Taylor
All right, well, it's been really awesome to chat with you about all things bird color, from the way they perceive it to the way they make them. Thanks for taking the time to join us today.

Dr. Allison Shultz
Thanks so much for having me, Scott. It's been really fun to talk to you, and I can't wait to hear what everybody thinks about color.

Dr. Scott Taylor
Birds are dinosaurs, and around here, we like our snacks. So we end each episode with a dinosaur nugget. Today's dinosaur nugget is that a bird's world is more colorful for many reasons.

First, it's the way they see color. They can see ultraviolet light with their extra cones, and their cones have oil droplet lenses that fine tune their vision even more.

Second, it's the diverse ways that birds can make colorful feathers. From pigments to structural color and reflectance to the way they combine the two. Even the color of the feather under the feather.

Think shingles on a house. Has a huge influence on bird coloration. That's a wrap on this week's episode. Okay, but why is a bird's world more colorful?

If you like this episode, do all the things leave a rating? Follow us. You've gotten the point by now, and we want to know what other big bird questions you have so we can tackle them on upcoming episodes.

So leave us a comment. We'll catch you next time. Byeee. Okay, But... Birds is hosted by Scott Taylor, with production and creative by Zach Karl.

Transcript Disclosure
This transcript was generated using AI and may contain errors or omissions. It is provided for accessibility and reference purposes only and may not perfectly reflect the original audio.

All audio, video, and images in this episode are either original to Okay, But... Birds (© Okay Media, LLC) or used under license/permission from the respective rights holders. Bird media from the Macaulay Library is used courtesy of the Cornell Lab of Ornithology as follows:

• Northern Cardinal audio contributed by Wil Hershberger, ML249823

• House Finch audio contributed by William R. Fish, ML12932

• Guinea Turaco audio contributed by Mike Andersen, ML140992

• Northern Jacana audio contributed by Gerrit Vyn, ML140224

• Common Eider audio contributed by Bob McGuire, ML235534

• Mountain Bluebird audio contributed by Dave Herr, ML47592

• Palm Tanager audio contributed by Curtis Marantz, ML88937

• Greater Bird-of-Paradise video contributed by Tim Laman, ML465370

• King Bird-of-Paradise video contributed by Tim Laman, ML455252

• Paradise Tanager audio contributed by Curtis Marantz, ML127399

Additional media used with permission under Creative Commons:

• Plum-throated Cotinga (Cotinga maynana) in Peru image contributed by Harsha Jayaramaiah, CC BY 4.0, via Wikimedia Commons

• Lovely Cotinga (Cotinga amabilis) image contributed by desertnaturalist, CC BY 4.0, via Wikimedia Commons