Science Friday - The B Broadcast: Bees, Beans, Bears, and Butterflies. May 19, 2023, Part 2

Episode Date: May 19, 2023

Science Says Eat More Beans Beans are delicious, high in protein, inexpensive, efficient to grow, and an absolute staple in so many cuisines. So why don’t Americans eat more of them? The average American eats 7.5 pounds of beans annually, which is only a few cans of beans every year. The answer is complicated, but one thing is sure: Beans have a PR problem. Ira talks with Julieta Cardenas, a Future Perfect Fellow at Vox, who reported this story. If you’re looking to chef it up, read some of the SciFri staff’s favorite bean recipes.    The World According To Sound: Feeding Time In this story from our friends at The World According to Sound, we’ll take a sonic trip to Yellowstone National Park. You’ll hear the sounds of two grizzlies feasting on a bison. It’s very rare that a bear can take down an adult bison, but they will chow down on animals that are already dead, like if they were killed by wolves or a car. The World According to Sound is a live audio show, online listening series, and miniature podcast, created by Chris Hoff and Sam Harnett.   Bees Have Feelings, Too Few pollinators have the charisma of bees, so much so that the phrase “save the bees” has become a calling card for those who consider themselves ecologically-conscious. There are more than 21,000 species of bees, ranging from the very recognizable bumblebees to the vibrant blue and green Augochloropsis metallica. Pollination ecologist Stephen Buchmann has studied bees for nearly fifty years, learning about everything from their natural behaviors to how they respond to puzzles. All of this has led him to a fascinating conclusion: bees are sentient, and they have feelings. Stephen joins Ira from Tucson, Arizona to talk about his new book, What a Bee Knows. Read an excerpt from the book here.   Pinning Down The Origin Of Butterflies One of the highlights of being outdoors in warmer weather is spotting a delicate, colorful butterfly exploring the landscape. There are over 19,000 different species of butterflies around the world—and all of them evolved from some enterprising moth that decided to venture out in the daytime, around 100 million years ago. But just where that evolutionary fork in the road occurred has been a matter of scientific debate, with many researchers positing a butterfly origin in Australia or Asia. Writing this week in the journal Nature Ecology and Evolution, researchers report on a new phylogenetic map of butterfly evolution, a lepidopteran family tree, combining genetic data with information from fossils, plants, and geography to trace back the origin and spread of butterflies. They find that butterflies likely split from moths in what is now Central or North America, before spreading to South America, crossing oceans to Australia and Asia, and eventually spreading to Europe and Africa. Dr. Akito Kawahara, professor, curator, and director of the McGuire Center for Lepidoptera and Biodiversity at the Florida Museum of Natural History and one of the authors of the report, joins Ira to talk about the findings and share some other surprising facts about butterflies.   To stay updated on all-things-science, sign up for Science Friday's newsletters. Transcripts for each segment will be available the week after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm I Refleto. This hour, we're talking beans, bears, bees, and butterflies. We'll hear what's a buzz with bee and butterfly biology. But first, the case for why we should eat more beans. I mean, they are delicious. They're high in protein, efficient to grow, and inexpensive. And they're an absolute staple in so many cuisines. But yet the average American eats just seven and a half pounds of beans annually. That's only a few cans of beans. beans every year. So why don't Americans eat more of them? Joining me now to talk about why the U.S. is behind on beans is Julieta Cardadus, a future perfect fellow at Vox who reported this story. Julietta is based in New York City. Welcome to Science Friday. Hi, Ira. Thanks for having me on. So nice to have you. You know, let's start out with the basics of just what a bean is, biologically speaking.

I think people get them confused. Sure. So a bean is a pulse, and a pulse is a subfamily of legumes. Pulsus are the edible seed of a legume, and they include lentils, peas, and beans. Soybeans are also a legume, but they're not a pulse. They're an oil seed. That's because the soybean is higher in fat, whereas pulses are low in fat. All right, I get it there. Now, environmentally speaking, when you're planting beans, why are beans such a good choice to plant? Sure. So beans make a lot of sense as a climate mitigation strategy, and they'll also help make global nutrition more accessible. And there's a few reasons why. First is that they use a lot less land to grow a good amount of protein. So 23% of agricultural land is used to grow plants, and from that we get 63% of global protein. On the other hand, livestock uses 77% of agricultural land, but only provides 37% of global protein. So in terms of land use, plants, including beans, are way more efficient. Beans are also adaptable to growing in different conditions so you can grow them in drier soils. So they're a good choice in terms of water use as well. And the second thing is beans are helpful in making soil healthy.

They're nitrogen fixing, which means the roots of legumes work in partnership with bacteria in the soil. And they end up leaving some of this nitrogen in the soil, which acts like a natural fertilizer. So when you grow beans in rotation with other crops, over time you're improving the soil health and helping all your crops grow. Ah, so that's why the indigenous way of growing with the three sisters, beans, corns, squash, works so well. Exactly. They all help each other out. And it's called Milpa in Spanish. So what is the most grown bean in the U.S.?

So the most grown bean in the U.S. is this, well, it's an oil seed. But soybeans are the most grown. And we grow a lot of soybeans, but we're feeding them to livestock animals. So when a livestock animal like a cow eats soy, they have to metabolize what they're eating. So up to 96% of the protein that they're getting from eating soy is lost through their natural metabolic processes. So they poop out a lot of the protein. I mean, instead of us eating it, yeah, we don't get it from them. And that makes a lot of sense.

You know, there's been a great controversy over the years about farmers not actually owning the seeds they plant because seed companies like Monsanto and Bear, they retain the rights to their own seas. Tell us about how that works. So before the 1980s, seeds were open for use. They were in the public domain. But then there were some changes to intellectual property law. And that made it possible for companies to create new sources. seeds and create patents for these seeds. The effect this ends up having is that the seeds become more expensive. They can end up costing twice as much. And it also means that big seed companies,

they can go after farmers if these farmers are growing proprietary crops. Yeah. And how does that affect what ends up on our plates? So because these seed companies want their seeds to be competitive and to be grown a lot and to produce a lot of yield, there's not a lot of incentive for them to have a wide variety of beans. So we all end up eating the same kind of beans. And in the U.S., that would be a lot of pinto beans, which are delicious, but, you know, there's more beans that we could be eating. That's very interesting.

As I mentioned earlier, the average American eats less, I found this hard to believe. It's less than eight pounds of beans a year? I mean, how does that compare to other countries? We're definitely not number one when it comes to bean eating. So Rwanda and Burundi are number one for eating beans. And in Rwanda and Burundi, people eat around 130 pounds of beans per year. In the U.S., we only eat around 7.5 pounds of beans per year.

In Mexico, the number used to be higher, but now people are eating around 20 pounds of beans per year. beans per year. So in the U.S., we definitely could play ketchup. Yeah, yeah. Yeah, to make beans more of a mainstay. And why is that? Why do we eat so little beans compared to other places? Well, in the U.S., there's a few cultural reasons that are holding people back from eating beans. One is people are probably intimidated because they don't know how to prepare them. They might be under the impression that you have to soak beans, and no one has time for that. But the good news is you can, you can just cook them. And if you have a pressure cooker, it's all the better. It's all the easier. The other factor that comes into play is that people associate beans with struggle during the early

onset of COVID-19. Bean purchasing shot up 400%. So everyone was rushing to stock their pantries with beans just in case, just to be prepared. But people don't necessarily want to associate struggle with the meals that they're making now. So beans have to overcome this. little PR hurdle. That's where there's like room for creativity from bean companies to make beans more of a hero of a dish. Yeah, because beans are treated like they're a second class food, right? Yeah, definitely.

And people might feel like getting a can of beans is like a culinary no-go. But I eat a lot of canned beans and there's a lot of potential. There's a lot of potential there. Yeah. You know, let me go back to that old saying about. beans, beans, beans, they're good for your heart, and the more you eat, I'm not going to go there with the rest of it. So I assume that's also a reason why a lot of people stay away from it because they're gassy. What makes them so gassy? So what makes them gassy is that people are not used to

eating an adequate amount of fiber. And so when you eat fibrous food, you may, you know, past wind. But once your body gets used to having an adequate amount of fiber, that hopefully won't keep happening. Yeah. And I understand this fear of beans and gassiness goes way back a long time, doesn't it? Definitely. Pythagoras, famous for his triangles, was afraid of beans. He and his followers thought beans contained human souls and that eating them would be a kind of cannibalism. And this might have been because Pythagoras thought beans, in his case Fava beans, because that was what was there, looked like little fetuses. And there's also the fact that in ancient Greece, wind and souls were related concepts. So he thought eating beans and passing gas was like the soul leaving the body. Oh, I can't. That's amazing. This was a smart guy, but those were different times. Yeah, those were different times. But then, you know, you have Diogenes, the cynic. who did not care for social pleasantries,

and he ate a lot of beans, especially Lupin beans. And he did this because Lupin beans were seen as a fruit of the underclass, and he wanted to be hardcore. And the fact that they're the musical fruit was also a plus for him, because if he could offend some normies,

then he would take that chance. And so, you know, you could be like diogenes if you want. I have no fear. No fear. No fear. No fear. Well, wait, something now I'll remember Pythagoras about for a different reason. I mean, and beans, of course, as you're saying, they have a

PR problem. Is there a way we can get over that? I mean, is there anybody working on that? Yeah. So we definitely should try to get over this PR problem. And there's nonprofits like Beans' How, which is trying to double bean consumption by 2028. And Beans' Howe is guided by the UN development goal of ending hunger, achieving food security, and promoting sustainable agriculture. all of those big goals from the little bean. And there's also companies like Rancho Gordo, which are selling heirloom varieties of dried beans and trying to create more of a market for heirloom beans.

That's cool. The city of Boston is also having their first ever Bean Town Bean Fest this summer. So that's pretty cool. Can't talk about beans without Boston, right? Yeah. Thank you very much, Julietta. Very interesting.

Thank you so much, Ira. It's bean real. You fit writing on our program. Julietta Cardinus is a future perfect fellow at Vox based in New York City. And if you feel like you being left out and want to chef it up, my colleagues at SciFri, put together some of their favorite bean recipes for you. Visit ScienceFriday.com slash beans to give them a try. You know what other animal doesn't eat a lot of beans?

Bears. In this soundscape from our friends at the world, according to sound, they did find something else to eat. These are two grizzly bears in Yellowstone National Park. Jennifer Jarrett captured this audio by placing a recorder next to the carcass of a bison. A few days after the bison was struck by a car and killed, two bears found it by the side of the road. What they're doing now is eating it. The world according to sound is created by Sam Hartett and Chris Hoff, thanks to the National Park Service and the Acoustic Atlas at Montana State University. You can hear more of their audio stories at the world according to sound.org.

B buzzing right along, we're talking bees right after the break, why these critters are so cool, and how do they really think? Stay with us. We'll be right back. This is Science Friday. I'm I, Iroflato. For the rest of the hour, we're going to talk about some of our favorite flying spring critters, bees and butterflies. Because it's that time of spring where flowers are blooming and the butterflies and bees are out and about, and they have powers and abilities far beyond what you may imagine. And since according to the UN, tomorrow is World Bee Day. What better way to celebrate than to create a buzz about these potent pollinators.

My next guest knows all about what most of us don't know about, what makes bees so great. His book, What a Bee Knows, Explores the Brains, Broad and Bombastic Nature of These Creatures, and What We Can Do to Protect Them. Stephen Buckman, Pollination Ecologist, and author of What a Bee Knows, he's based in Tucson, Arizona. Welcome back to Science Friday. Hi, Ira. Great to be here. Here we go. It's been like almost 20 years. You were on our show back in 2005, and I got to ask you, has the General public's attitude toward these changed anything for the better since then. Well, yeah, the public has certainly caught on to bee declines.

We've actually had one bee, Franklin's bumblebee from the Pacific Northwest, a bumblebee with the smallest range of any bumblebee in the world, probably go extinct. And sad as that is, we have four or five other species, including the rusty patch bumblebee, Bombus aphanus, that are also declining as well, perhaps due to some foreign interlopers, we call this pathogen spillover. So we could have had some U.S. bumblebee queens that were collected, brought to European insectaries, commingled with their bees, and brought back with some little microbial hitchhikers. So we have some things like that happening.

You know, I'm glad that you brought up bumblebees to begin with because, as I understand it, there are 21,000 types of bees worldwide. And I've heard that the honeybee is the most studied insect on the planet because they're social. They can live in boxes that humans can control. But how much of what you've learned about what a bee knows is generalizable to the other 20,000 bees, most of which aren't social? Right. I've studied honeybees and bumblebees and social stingless bees and different places around the world. But mostly I like to hang out with the little solitary bees that nest in the ground. I like to call these single moms with families to feed.

They don't get any help. They often don't get any respect. They get blasted with pesticides. But all of these bees are fascinating because they have brains that are the size of a poppy. seed with about a million neurons, but they're doing just phenomenal things. They're problem solvers. They're likely self-aware. They may have a primitive form of consciousness. We're just really now in the last decade or so figuring out what bees are all about in terms of the inner bee. Well, that's what I want to get into some more. Tell me about in detail these things that you just

mentioned because you argue in your book that bees are sensioned, they have self-awareness, they feel pain, they plan for the future. Tell me how we know this. Yeah, well, some of it's a little tricky, obviously, because, well, let's consider consciousness. I mean, philosophers have been arguing about this for millennia. I mean, how do we even know that another person is conscious? But all kidding aside, people are arguing, scientists are arguing about whether bees feel pain, for example. And I find this a little amazing. When I grab a bee, let's say in the lab with a pair of forceps and it gives me an alarm buzz, turns around, tries to sting me, I think that's a good affirmation that they don't like it.

They're feeling something like pain. bees also have something called noisusceptor sense cells along with other insects. That's a good indication that they're feeling nauseous stimuli or trying to move away from them, moving out of potential danger. Sentience, we can get a little bit in the weeds on the definition, but I believe that bees are sentient. The first definition of that is that an animal is capable of experiencing pain, and others have expanded on that definition to include the capacity of them to experience

sensations and emotions. But other than perhaps anxiety, I'm not so sure that I'm willing to go quite that far for bees. And self-awareness? Yeah. There was an interesting experiment that was done with small, medium, and large bumblebees. basically, as you know, insects don't get bigger as adults. It's all dependent on how much food you ate as a kid.

So the experiment that was done was to train bumblebees to go through a slit to get to some sugar water on the other side. And so here you come as a fat bumblebee, and the fat bees turned sideways to squeeze their way through their little slit and pulled their legs. So to me, and the other researchers that actually did that experiment, that to me indicates that they have keenly aware of their body size. So they were self-aware. That's amazing. There's even been research that bees can experience PTSD-like symptoms. Yeah. Some experiments by Lars Chitka, a professor in London, he and his students came up with a system where the bees in a little foraging arena were confronted with fake spiders with these little padded foam claws. And if a bee got too close, the foam spider grabbed the bee and held onto it for two seconds. And later, when those same bees were tested, they, you know, wanted no part of that.

didn't even get close to the robotic spider. That's amazing. Is this something all insects possess, or is this an anomaly among insects? Well, we don't know yet. So far, it's been mostly researched with fruit flies. So, for example, we know that fruit flies have, for example, an ion channel associated with nociceception, that noxious stimuli avoidance called TRPA1. And it's possible that bees also have that ion channel.

But again, we've mainly worked with honeybees. They're sort of the white rat of the insect world and a little bit with bumblebees. But most of those others, you know, the nearly 21,000 species of bees around the world, we don't really know much about their behaviors. Because I understand there's been research that bees can recognize,

different human faces, correct? Yes, yes. Do they see you coming in coming by and wave? Exactly. Well, I think if you're a bad beekeeper one day and they recognize your face, you don't want to go there the next time. But yeah, bees, it's not quite so strange if you think about it, but bees on a foraging day have to go out and recognize,

often cases dozens of flowers by their shape, their colors, their scent. So maybe identifying a human face is pretty simple compared to what they have to do in terms of learning to work different flowers to get at the pollen and nectar rewards. Right. Speaking of flowers, we've all learned in school that when a bee goes out and finds some flowers, it comes back to the hive. I'm speaking of honeybees, maybe the other bees do this, the other social bees, they do some sort of dance and they teach each other things, correct? Well, it is a little oversimplified, but basically back to the 1920s, 30s, and into the 40s, Nobel laureate Carl von Frisch, an Austrian researcher was one who did most of that work with honeybees.

And the waggle dance stuff has been refined, and we now think that there are. odors and other things involved, and it's not as purely symbolic as we once thought. But by and large, it's pretty remarkable. So the 11 species of honeybees, the scouts go out, they find a productive flower patch, they acquire odors on their bodies, they've got a honey crop full of nectar, they come back, they regurgitate some of the nectar to other. bees at the nest and then they do what is called a round dance if the flowers are close or a waggle dance if they're farther away. So basically the bees orientation on the comb is pointing either directly toward the flowers or at an angle that is with respect to the

orientation of the bee in the sun. So pretty neat. Other bees don't really do that. I mean bumblebees make some little buzzes in the nest, some stingless bees put down little odor droplets on vegetation to sort of lead by signposts bees out to flowers. But the vast majority of bees in the world have to find flowers on their own, have to navigate to and from them, and then go out again. So pretty amazing navigational abilities that they have. Do they use like ants do?

Ants use their sense of smell, correct, to get to leave trails and pathways? Do bees have a sense of smell that they might go back to a patch of flowers by smell, or is it purely by navigation? No, it's a combination of optical navigation, the sun compass, their fine memory of time. For example, if you put out a reward at a certain time every day, the bees will anticipate that and come back. But it is a mix of that optical navigation and also sense that they can smell from a distance or, as I said, can even be clinging to their body when they get back to their nest. Right. So bees know how to tell time? They do, yeah.

By the sun? Right, by the position of the sun in the sky. And then just probably an internal clock that is pretty accurate. So they know when certain kinds of flowers, maybe their favorites, say they're opening in the morning, they'll be back there the next morning, anticipating when they open up. Amazing. And you said before how tiny a bee's brain is. How do they get all of this into that tiny little spot? Yeah, it's pretty amazing. Of course, it doesn't really divided into hemispheres and a cerebellum and all the, weird parts that human brains have. But it is comprised of about one million neurons,

and there might actually be one billion synaptic connections. So much smaller than the perhaps 80 to 100 billion neurons in our brains, but they do a lot of amazing things. There are structures inside the B brains called mushroom bodies that look like mushroom. and they do a lot of complex processing, and it's likely that memories are consolidated there. We didn't talk about bees sleeping, but hey, go. Let me just remind everybody first that this is Science Friday from WNYC Studios, talking with Steve Buckman, author of What a Bee Knows, based in Tucson.

Yes, tell us about sleep. Yeah, well, bees can sleep a lot, six hours at night, maybe 10 hours during the day. And they go through different stages of sleep. First, there is a wakefulness type of sleep when their antennae. The feelers are going like crazy. And then the final stage of their sleep is a deep sleep when they're really quiet. They have kind of a rigid posture and their antennae don't move. But really what we think is going on is that bees are consolidating.

their navigational memories during sleep. So pretty interesting stuff. You know, I remember back in the 1960s when there was a debate about running the laboratory rats in a maze versus studying rats in the wild. How much can you learn about learning them, watching them in the maze when you should be studying them in the wild? And I'm thinking about that now about you talk about... that the honey bees in our boxes that we keep them is sort of the lab rats of science study.

Could we learn a whole lot more from bees by studying the ones that are in the wild? Yeah, that's exactly right. We can learn a lot as scientists or naturalists by watching bees in the wild, although for some of these studies, we need to bring them into the lab where we can control some of the different stimuli that they're responding to. Tell us about what we, in the short time we have left here, what we as individuals can do to make the world a more be-friendly place. Yeah, the main thing we need to do is to stop blasting them with insecticides.

In the United States, I think there are only three states that have banned the neonicinids, neonicotinoids, which are really nasty systemic insecticides. And they show up in lawn care products. And they're also in potted nursery plants that we buy. Many countries in the EU have banned them, and they should be banned here. And there are other things that are harming bees that we're just now learning about. I'm working with a group of scientists at Cornell and the, University of California and other universities.

And we found that while herbicides, which are weed killers, are generally not harmful to adult bees, and this is something that that industry will tell you, we find that herbicides, when they're brought back into the nests of these solitary or social bees, that they are eaten by the larval bees, the bee grubs, and they knock out the health. helpful bacteria and yeast that help them. I mean, just like we need probiotic, helpful microbes to live a healthy, happy life, bees need those too. Yeah, they need a healthy microbiome, just like we do. Yeah, they do need a healthy microbiome.

The simplest thing that you can do if you're not blasting things with insecticides are to plant a diversity of flowers, especially native wildflowers that are adapted to the local region where you live. And so that these are appearing and flowering in most months of the year, because some of these, especially social bee colonies, are long-lived. Most of those bees that I talked about that are ground nesting need some bare ground. So if you don't put down plastic sheeting to keep down weeds or you don't put in gravel or redwood chips or something like that as a mulch, that'll help bees a lot, too, because they need that bare ground to nest him.

That's something good to know for this planting season. I'm going to keep some of my spaces beer. Thank you, Steve. This is fascinating. It's a great new book. Thanks so much, Ira. I'm glad you're enjoying it. Steve Buckman, Pollination Ecologist and author of What a Bee Knows, a Great Book.

I highly recommend it. We have to take a break. Again, when we come back, turning from bees to butterflies, and why butterflies are just moths that fly during the day. Really interesting history. We'll be right back after this short break. Hey, folks, just a reminder that Science Friday depends on donations from our audience, and that means you help fund the radio show each week, plain and simple. So, if you find value in what we do, please go to Science Friday.

com slash support and give what you can. Any amount makes a difference. And thanks. This is Science Friday. I'm Ira Flito. One of the things that gives me the greatest enjoyment when I'm outdoors is watching butterflies. You catch a glimpse of a delicate, colorful butterfly flitting about. It's like a mobile flower. But it turns out that the evolutionary history of the butterfly has been a matter of scientific debate. I mean, where did the first butterflies come to be? Writing this week in the journal Nature Ecology and Evolution, a team of researchers crunch the genetic data on butterflies from over 90 countries to try to put a pin on the butterfly origin. Joining me now to talk about the work and what they found is Dr. Akito

Kawahara. He's professor, curator and director of the McGuire Center for Lepidoptera and biodiversity at the Florida Museum of Natural History in Gainesville. Welcome to Science Friday. It's a pleasure to be here. Nice to have you. There are lots of species, right? 19,000 species of butterflies around the world, but there is a question about where they evolved?

That's right. Until now, we really didn't know where they came from. Scientists had thought that they might be originating in Australia or Asia, but we didn't really have a very good idea until now. Using the DNA data, we used fossils and geographic information and also plant data as well, like what kind of plants butterflies feed on. We tried to trace the history of how butterflies evolved on this planet. And what we discovered from this is that butterflies likely originated either in North America

or Central America and spread throughout the world, starting in North or Central America and then going into what is now South America, crossing various oceans and crossing over to Asia into Australia and eventually going into Africa and Europe. Wow, really interesting. Well, now that you have the geography pinned down, let's talk about the evolution, where do butterflies come from, evolutionarily speaking? Butterflies come from moths.

They're actually a group of day-flying moths. So moths are hundreds of millions of years old, probably three or four hundred million years old, and they came from aquatic insects. They're related to these insects called caddus flies. And what we think happened is that these first moths came out from the ocean and started to feed on these very, very kind of primitive plants. And then when angiosperms, these flowering plants, took over the world,

moths started to take advantage of that. And then we think one group of moths somehow became day flying and just took advantage of the flowers that were available during the day. So how did you trace back where that event occurred where the moths and butterflies separated a bit? Yeah, so for this study, what we did was we went into museum collections. So we have about 100 authors that were part of this study. And we obtained tissue, DNA tissues, from museum collections, pinned specimens in the collections. And we took the DNA from these specimens with, of course, their permissions and so forth. And we traced their evolutionary history. We built what's called a phylogeny, a family tree of butterflies from thousands of specimens. And then

once we had that, we also included fossils, and that gives us a time point on when particular events took place. So once we have that, then we have a pretty good idea of how old butterflies are. And so our analysis led to the conclusion that they're about 100 million years old. And then with that, we included geographic information from present day butterflies and then trace that back onto the tree. And when you do that, you can figure out where they came from and how they spread across the world. Wow, that's cool. You mentioned museum collections. You see the dried pin displays of butterflies. Is there enough DNA there for you to sample and using your research? Yeah, the technology has gotten so much better in the last 10 years or so that we can now take

DNA out of these dried old museum specimens and get pretty good DNA sequence data that we weren't able to do in the past. So in this study, one of the oldest specimens is from the 1940s, but we've done other studies where we can take, you know, that we've shown to take DNA data from specimens dating back into the 1800s and so forth. Do you use live butterflies at all? Go around catching them with a net, you know, like we see people running around? Yeah. You know, this project was really fun. It involved traveling to museum collections to obtain museum specimens, but it also involved going out into the field, too. So when we first started this project in 2015 or so, one of the first things we tried to do was, oh, look for butterflies. So with the proper permissions

and so forth, we went to different places around the world to look for particular butterflies that we could sample to include in the study, and we were able to do so. You mentioned that you also looked at fossil butterflies, but this isn't a Jurassic Park DNA in Amber situation, is it? That's right. It's more compressed fossils. So butterflies that have happened to, you know, be preserved in layers of dirt or clay are the ones that we have included in this study. But, you know, compared to other organisms like, you know, mammals, butterflies aren't, they don't have very hard parts. So they don't preserve very well in the fossil record. So we had to use what we could. And we used about 14. fossils in this study. Are there species that you really wanted for the analysis, but you didn't have, so you had to go hunting for them? Yeah, one of the butterflies that has been this enigma, or it's an incredibly interesting butterfly, is it's called Baronia Brevichornis. It's this butterfly found in Mexico, and it's been my kind of childhood dream to see this butterfly alive.

It's the so-called ginko of butterflies. But we were able to go and get a specimen of this for this study. And it's a very, very unusual small-tail butterfly that's very different from what we think, you know, that we typically see in modern butterflies. But it's still around in Mexico. Let's talk about this evolutionary leap. Can you actually see in the records of butterflies and moths where it happened? Is there a definite, you know, a little mark there? You know, different studies have shown that butterflies have come from moths. So I think there's a pretty strong scientific agreement that that's what happened. And, you know, almost all modern butterflies are day flying. There are exceptions. However, there's a very, very interesting group of butterflies.

There's only about 30 species of these butterflies, but they're found in the neotropics, so in South America and Central America, and they are very cool because they are actually night flying. And what's even more interesting about these particular nocturnal butterflies is that they have ears or hearing organs in order to hear predatory bats at night. No, really. Yes, it's really, really interesting. Because the bats are, they're food for the bats. That's exactly right.

They're food. So they have to protect themselves, and they have these ultrasonic hearing organs on their bodies that allows them to hear the bats when they're hunting. And so the daytime butterflies, they don't have those. That's correct. In some daytime butterflies have ears, but they're not ultrasonic in the sense that they can, you know, hear things like footsteps or low-frequency sounds, you know, animals or predators potentially approaching them. They can hear those kinds of things. Some of them can. But the ones during the day do not have these sophisticated hearing organs that a lot of moths have and these nocturnal butterflies have. Is there something that you personally don't know about them or maybe science in general that you'd really like to know something.

something like the next big butterfly mystery that needs to be solved? I'd say we're in a time where we're doing a lot of research on the genetics of butterflies and moths. And one of the things I'd really, really like to know more about is how they're able to see. So the vision of butterflies is an area that we're very, scientists are very interested and also how they smell and how that's genetically programmed. I think that's an area of research that's very up and coming, and a lot of it will know a lot more in the very near future. Do we know that since they go to flowers like bees do, is their eyesight, anything at all like a bee's eyesight? Yeah, so butterflies are really interesting because they have what are known as compound eyes.

So instead of one big single eye, they have millions of these tiny lenses or what one could call facets. And these all function together to be able to see the way. world around them. And each one has a photoreceptor that can sense a particular color. So with this sort of assembly of different colors that they can perceive, they can kind of put together this mosaic that they see from the outside world into a single image. And they can do this in ultraviolet as well. People have this image of butterflies as sweet, pretty things on the wildflowers, but they're not all like that, are they? That's correct. There's a lot of butterflies that are brown and kind of drabby looking. And the opposite is true for moths as well. There's many, many moths that are out

there that are extraordinarily beautiful. I would say even more beautiful than most butterflies and most people are extremely surprised when they find out that it's actually a moth. So moths are extraordinary. You know, I was surprised to learn we've talked about bees previously that some bees are Meat eaters, are some butterflies, perhaps meat eaters, too? Yeah, it's funny if you ask this question because a lot of people think that butterflies, you know, come to flowers and that's what they do and they pollinate, and that is true. However, a lot of butterflies also come to different kinds of things. So some butterflies only come to things like tree sap, others only come to decaying material,

others come to feces. We did actually a field expedition to Africa, and there's this particular group of butterflies. They're extremely cool. They're very, very fast. You can't actually really catch them in flight because they're just so fast you can't even see them. But the one time you see them is when they land on the ground, and they love poop. They love baboon poop. So you have to be kind of standing around in front of the poop waiting for these butterflies to show up,

and then that's when you actually see it, and that's when you have a chance to catch one if you're trying to catch one. Were you as surprised as I am now listening to this when you discovered that? Yeah, it was fascinating and pretty smelly expedition, but it was a lot of fun. You know, when people go to these live butterfly exhibits, the butterflies sort of land on you, is there something on you they are looking to eat? Yes, the butterflies, when butterflies land on you, it's typically because they, they are looking for minerals. They are actually attracted to sweat. And if you look very closely,

oftentimes you'll see their mouth part, which is a little straw called a proboscis, kind of probing around looking for things to drink. So it's likely that they're attracted to your sweat. So like the salt, the salt in your sweat or minerals? Salt and other minerals. Really? So they like salt also. They like mineral. Well, obviously they're animals. They need those kind of minerals too. That's right. We talk about species of plants and animals that are sort of living fossils that haven't really changed much over time. I'm thinking like sharks in the animal kingdom, ferns and the plants. Are there butterfly species that fit that category?

Yeah, some butterflies have not, at least we think, have not changed that much. The Boronia butterfly from Mexico is certainly one of them that has not appeared to have changed that much. They have very unusual features that almost no currently, existing butterflies have in the moth world, too, and remember butterflies are really just a derived group of moths. There's some really, really ancient moths that seem to have not changed. They still feed on ferns and various primitive plants, and their behavior seem to have not changed for millions of years, hundreds of millions of years. That is fascinating. Am I Refledo, and this is Science Friday from WNYC Studios. So how did you get into this? What made you start to study? Butterfly.

Well, you know, it's funny. When I was a kid, I grew up in Japan, and I was really fascinated by insects. And it was driven mainly by my father, who was an artist, but he also had an appreciation for natural history and thought that kids should be able to go outside and look for nature and study nature and so forth. So I feel very fortunate that he provided me with that opportunity because, you know, every weekend we'd go collect butterflies and look for butterflies. And that sort of just, you know, it became, Eventually a profession, I realized that I could actually be a professor to do this. And I just kind of followed that dream. And here I am. So that shows the importance of bringing kids outside, getting it to nature. Yes, I think it's extremely important. Something that I'd say we all, you know, as scientists should be doing. The world is changing pretty quickly and natural environments are disappearing or changing.

And I think appreciation is really important and getting our kids out there. Because kids in general, you know, they're innately interested in the living world. And with insects and butterflies, you know, you just have to look in your yard and they're there and just stop and see. And they're just fascinating and beautiful. And there's so much to learn from them. And what I hear you saying about nature changing is get the kids outside to look at the butterflies while the butterflies are still here to look at. That's right. The butterflies are still here to look at.

But I guess I would say that some of them are disappearing. And that's something we need to be aware of. And there's a lot of things we can do to prevent that from happening. Things like, you know, planting native flowers and plants that are used by butterflies, creating habitats that are good for them. I think these are just really simple things that we can all do. And if all of us do it together, I think it will have a big impact. Is it harmful to grab a butterfly by the wings like, you know, we try to do in the garden?

So butterflies have scales on their wings. And they're, is that right? Butterflies and moss are in this group of insects called Lepidoptera, meaning they have scales on their wings. So when you touch the wings, the scales can oftentimes come off. So you have to be pretty gentle when you do so. And you don't really want to hold the butterfly by the body because that can harm them. It can hurt their legs and so forth. But typically holding them by the wings gently is okay as long as you don't rub too many of the scales off.

So now that you know that butterfly started. in North and Central America, does that change our understanding of them at all? Yeah, definitely. I think now that we know that they came from North and Central America, how they spread across the world is very different from what we had thought before. You know, there's these certain group of butterflies that only feed on particular plants that are found in places like Siberia or South America or wherever it is. And so getting this broad geographic understanding now gives us an insight into how butterflies spread across the world. Do you have a favorite butterfly we could share with our audience?

Or is it like children? You say, you know, I have so many of them. I can't narrow with that. Yeah, I'd say one of my favorite butterflies is this butterfly called the Sunset Morphal butterfly. And it's this butterfly that's only found in the Amazon jungle. And I have seen it multiple times on field trips. And growing up in Japan, I read about this butterfly when I was a kid. And I've always wanted to try to see one up close.

And I've only seen them from far away. And one day, I think I'll be able to see one up close. But it's a beautiful, big butterfly that's orange and white and black and extraordinary. It's a very, very slow-flying butterfly, but just beautiful. And something I'd love to come close to one day. Well, we wish you good luck in finding that butterfly. Thank you very much. Thank you very much for taking time to tell us all about this.

This was fascinating. Thanks again. It's great. Dr. Akito Kawahara, Professor, curator and director of the McGuire Center for Lepidoptera and biodiversity at the Florida Museum of Natural History that's in Gainesville, Florida. And that wraps it up for this week. If you missed any part of this program or you'd like to hear it again, subscribe to our podcasts or ask your smart speaker to play Science Friday. You can say hi to us all week on social media, Facebook, Twitter, Instagram, or email us, our address, SciFri at ScienceFriday.com.

Send us feedback. Tell us what you'd like us to cover too. Have a great weekend. We'll see you next week. I'm Ira Flato.