Science Friday - Evolutionary Biologist Neil Shubin, Bee Virus Behavior, Search for Lost Apples. May 1, 2020, Part 2

Episode Date: May 1, 2020

The Twists And Turns Of The Evolution Of Life On Earth In an evolutionary tree, neat branches link the paths of different species back through time. As you follow the forking paths, you can trace common ancestors, winding down the trunk to see the root organism in common.  Evolution in the real world is a little messier—full of dead ends and changes happening beneath the surface, even before new traits and species appear. And the research and science that gave us a better picture about how life evolved on Earth can just be just as complicated.   Evolutionary biologist Neil Shubin, author of Some Assembly Required: Decoding Four Billion Years of Life, from Ancient Fossils to DNA, explains how technology like DNA sequences has allowed scientists to fill in these gaps in the story of evolution.  A Viral Battle In The Honey Bee Hive New research published this week in the Proceedings of the National Academy of Sciences indicates that honey bees infected with a virus may alter their behavior in ways that slow the spread of the infection. At the same time, infection with the virus may help the bees sneak into neighboring hives, potentially spreading the virus to new hosts. Adam Dolezal, an assistant professor of entomology at the University of Illinois at Urbana-Champaign and one of the authors of the study, describes the research, and the evolutionary arms race that may be taking place between the bees and the virus. The Malus Domestica Detectives Earlier this month, the Lost Apple Project in Washington state announced a fruitful bounty: Ten varieties of apples found in the Pacific Northwest that had been considered “lost” varieties. These include the Sary Sinap, originally from Turkey, and the Streaked Pippin from New York. To find these varieties, the researchers used an old school identification process—the partner organization, Temperate Orchard Conservancy, compared the mystery apples to watercolor paintings commissioned by the USDA from the 1800s and early 1900s. It’s a time consuming process, and positive identification can take years. Joining Ira to talk apple identification are Shaun Shepherd, pomologist at the Temperate Orchard Conservancy in Portland, Oregon, and Gayle Volk, plant physiologist at the USDA in Fort Collins, Colorado. 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 Iroflato. A bit later in the hour, a conversation with evolutionary biologist Neil Schubin about what salamander tongues and fish swim bladders. Yeah, can tell us about the story of evolution and a hunt for long lost apples. But first, the coronavirus has brought dramatic changes to our behavior, right? From wearing masks to handwashing to sheltering at home, all aimed at slowing the spread of disease. But a different virus may be causing some of our neighbors to be changing their behavior too. I'm talking honeybees. Science Fridays Charles Berkwist has more. Israeli acute paralysis virus is one of many diseases that can affect a honeybee hive. Over the course of a few days, infected bees first become paralyzed, then die. The virus is also linked to the spread of

the varroa mite, a tiny parasite that attacks bees. Writing this week in the preceding of the National Academy of Sciences, researchers say that they found that Israeli acute paralysis virus, or IAPV, seems to be locked in an arms race with the bees, with competing forces both pushing the spread of the virus and tamping it down. Joining me now to talk about what they found as one of the authors of that report, Adam Dozel. He's an assistant professor in the Department of Enomology at the University of Illinois at Urbana-Champaign. Welcome to Science Friday. Thanks for having me. First, What is Israeli acute paralysis virus?

IAPV is a RNA virus that is spread through a lot of different mechanisms by honeybees through their feeding of each other, but primarily like you mentioned, through varroamites. And it's a virus that bees can carry around with very minimal symptoms a lot of the time, but when it reaches high enough levels, causes these paralysis-like symptoms. And we know that this is a virus that is pretty common in hundred, honeybee hives, at least in the U.S. and through much of the world, but it's not quite ubiquitous like some other honeybee viruses are. And you deliberately infected some of your hives with the virus in order to observe its effects? That's correct. Yeah. So in this study, we used experimental

infections where we just produce particles of this virus. We can actually just dissolve it in sugar solution and then feed it to bees for our experiments and infect them in a very controlled way. Once you do that, what happens to those bees? What do they start doing within the hive? So in the study that we did here, we fed them a quantity of virus that doesn't cause a lot of mortality. It infects the bees, but it doesn't cause them to all become paralyzed and die. And what we found is that inside of a colony or in lab observations that mimic that, bees who are infected experience a lot less of this mouth-to-mouth food sharing behavior called trophylaxis. This is a behavior that bees do all the time in their colony. They're touching each other, grooming each other. They're sharing food. And so this is a behavior that's

critical for colony success, but is also something that can transmit pathogens between individuals. And so we found that whether bees were infected with the virus or if the immune system was just turned up, that they received less of these behaviors. They were less socially active in that way. So is it just that the bees are just holling up somewhere and saying, I don't feel good, I'm going to go take a nap, so that they're not interacting as much? That's a really good question. Because this virus does cause paralysis at high levels, you might expect bees to move less. But in fact, at the infection levels that we used, they appear to actually move more in some situations. And at the very least, they move the same amount as a normal bee. So no, they're not holing up. They're walking around the colony. They're interacting with other bees and they're going in different places.

but they are less likely to be part of that mouth-to-mouth food sharing behavior than control bees. Does that reduce the transmission of the virus within the hive itself? We think it does. For this study, we are unable to actually track pathogen movement precisely, but we know from other studies that IAPV is transmitted orally, that it is transmitted through that mouth-to-mouth food sharing behavior, both between workers and also between the workers and the queen. And so by reducing this, we think that this reduces the overall probability of the disease being transmitted through the colony.

You know, who's initiating that restraint? Is it the bees saying, I don't feel good. I'm not going to interact with you. Or is it somehow the healthy bees recognizing, hey, that bee's not right. I'm not going to stay away from them? At this point, we're not 100% sure. Either one would be a viable mechanism to reduce that behavior. However, one of the other things that we did in this study was measure the particular hydrocarbons,

the chemicals on the outside of a bee's body that communicate information to other bees. And we found that when bees are infected or their immune system is turned on, their hydrocarbon profile changes. So they appear to smell different. And so there is a signal change there that could be picked up by the healthy bees and cause them to change their behavior in response to the sick bee. But you found that there was something else going on when those infected bees left the hive and encountered a neighboring hive? Right. So we did a series of experiments where we took infected bees or immunostimulated bees and we presented them to the guard bees of another colony. The guard bees of colonies are their line of defense against intrusion from predators, but also from other bees from other colonies who might come in and try to steal honey or spread pathogens.

And we found that bees who were infected with IAPV received a lot less of the guard aggression that we normally see. And we saw this both in lab assays where we can record their behaviors carefully. we also saw it in real field colonies that we set up, and then we introduced to their entrances infected or uninfected bees. And we found that those who were infected were accepted into this foreign colony about twice as often as controls. And so it appears that IAPV is giving the bees who are infected some ability to circumvent other colony's defenses

to somehow get through that line of guards and enter into the colony itself. Is that smell cue like an identification system, like a passport, or is it some sort of calming? These aren't the droids you're looking for confusion thing? Honeybees use these hydrocarbons, these chemicals on the outside of their body, as a marker of what colony they belong to.

When honeybees return to their colony, the guard bees normally stop them and smell them with their antennae and C, do you smell like someone who lives in this colony? And if they do, they're allowed entrance. And if they don't, then they are often attacked or rejected, prevented from entering. And so we see a number of different compounds changing with infection, but we don't know exactly what any specific one might be doing. Whatever's happening, it's allowing bees to gain entrance into really appears any foreign colony.

So they're not mimicking the smell of Colony Bee over there because they don't know it. But something about their profile is making them more acceptable to those guard bees. And it's not just that the guard bees are ignoring them. The guard bees do stop and antonate them and even do that mouth-to-mouth food sharing behavior with them. So it's not as if they're invisible. It's something else going on. They're there. The guard bees interact with them.

but then they ultimately make the decision to allow a lot more of them into the colony than they normally would. So if this is a sort of evolutionary arms race going on here between the bees damping down the spreading behavior within their own hives and the virus somehow encouraging spreading outside, who's winning the race? That's a really good question. One challenge I'll note is that we really don't know how effective that tamping down effect is. The evidence we have suggested this is a pretty general response, and people have seen similar responses with other types of stresses to bees. It may be that this is just a general response that happens when bees are infected with lots of different pathogens. And we actually don't know how successful it is at preventing transmission of IAPV.

Similarly, we don't really know how successful of a strategy it is to get diseased individuals from colony A to colony B. But it seems that on a whole, the ability to move from an infected or infested colony to susceptible ones in your apiary very quickly would be more successful. How do you even go about observing and tracking the behavior of a whole hive full of bees and monitoring? This one infected bee is doing a certain behavior. People have been using what are called observation hives to study bees for a long time. These are special colonies with glass walls. And they're usually kept inside of a building so a human can observe them and write down what number marked bees are doing. But at any given moment, you can only observe so many bees. Even with a video camera, it becomes very challenging to figure out what's going on.

And so one of the exciting things about this study is that I was able to work with Tim Gernott and Gene Robinson, who had developed recently an automated behavioral monitoring system. And this system, it uses an observation hive just like bee biologists have used for a long time. But instead of a human observer, each bee has an individualized little tag on its back that looks kind of like a QR code. And a camera takes a picture of that colony every second for the entire experiment. And then a computer is able to figure out where every bee is, its orientation, and then it's also even able to look at, how their heads are oriented and how their tongues are to identify this food sharing behavior. And so it's able to identify orders of magnitude more of these behaviors than a human observer ever could. And so it's giving us an opportunity to see B behavior at a resolution that really has never been

before possible. Does this study have any parallels to how humans are living today? I think that it's hard not to draw some parallels. here. Honeybees like humans are really social animals. They live in these large groups. They interact with each other constantly. They need to interact with each other constantly. They become very stressed if they don't. But they also have the ability to sense that a pathogen is making them sick or making one of their group members sick and do behaviors to reduce the spread of that pathogen. And this is something I think that we could view very similarly to our own public health efforts to reduce

social contacts among humans in the face of a pandemic, that we can change our behaviors to change the virus's transmission. Adam Dozel is an assistant professor in the Department of Enomology at the University of Illinois at Urbana Champaign. Thanks for joining me today. Thank you. And if you'd like to see some images of barcoded bees, visit our website at ScienceFrily.com I'm Charles Bergquist for Science Friday.

When we come back, we'll talk to evolutionary biologist Neil Schubin about the scientists that made big breakthroughs to fill in the picture of our evolutionary history. Stay with us. This is Science Friday. I'm Ira Flato. You've probably seen an evolutionary tree with its neat branches linking the paths of different species.

If you follow down the tree, you can trace back to common ancestors and wind down towards the trunk. to see the root organism. Evolution in the real world is a little messier, full of dead ends and changes happening beneath the surface even before new traits and species appeared. And the discoveries and scientists that gave us a better picture about how life evolved on Earth? Well, those stories could be just as complicated. Evolutionary biologist Neil Schubin writes about all these stories in his new book, Some Assembly Required,

decoding 4 billion years of life from ancient fossils to DNA. Producer Alex Lim spoke with Dr. Schubin. Hi, Dr. Schubin. Welcome to Science Friday. Well, thank you for having you. It's great to be here. Paleontologists have been digging up fossils that show evidence of changes in species for a long time.

So how does the technology like DNA sequencing add to the evidence? What other connections or gaps does it allow you to fill in? We've witnessed and we've lived in the past. several decades through a genetic revolution, where we now have genome projects, completed genomes for many different kinds of species. And we can now leverage that information to ask, what are the kinds of genetic differences that are associated with the major changes in evolution we see in the billions of years of the history of life? I mean, paleontologists have gotten really good at finding new fossils that tell us about how great transformations happen.

Now we have this whole new data set to mine, and it's really a remarkable. couple of time. It was totally humbling for me because I was training to be a fossil hunter. And this was the mid-late late 1980s when we were finding all kinds of new genes that tell us about how development from egg to adult happens. And it was showing sort of a basic toolkit that builds animal bodies, it's different as flies, you know, worms and people. And that's a game changer. Right. And your book kind of does double duty. You outlined the big discoveries in evolutionary research, but you also look at the people behind those discoveries. Did you go through footnotes or were there any interesting archives that you had to dig into to find some of these people? Yeah, well, some of them I knew about

before. Others I happened upon through just serendipity in my own life. So I'll give you one example. You know, I was a co-director of the Marine Biological Laboratory in Woodsville, Massachusetts, a few years ago. And I heard stories of a remarkable womanhood worked there in the 1800s by the name Julia Barlow-Plath. And so I went to the library there and just, you know, the buzz about her, people had talked about. And I saw her story, and her story is sort of science and overcoming challenges in a nutshell. This was a woman trying to do science in the 1800s, made a fabulous discovery, which is incredibly important for understanding evolution, which for experts in the audience that she helped discover a new cell type called the neural crest,

which is big in the origin of vertebrate organisms. But she found this discovery, and nobody believed her because it ran against the current dog move. And she couldn't find a job of science. and ultimately quit science, but she became mayor of Pacific Road, California, and ended up staying in Monterey Bay. I mean, it doesn't get better than that, right? I mean, it's just amazing. And another really interesting person you talked about was a critic of Charles Darwin, just his name alone, is interesting. St. George Jackson, Mavart, who in response to Darwin's idea wrote a book called On the Genesis of Species, kind of a dig at Darwin. Oh, it was a dude.

So, I mean, what was his main criticism of Darwin's theory of evolution? Yeah, Mavart was like a professional curmudgeon, honestly. And a brilliant one at that. I mean, he, you know, he reputed his Anglican faith and became Catholic, but then couldn't get into college. So he studied natural history. He was a friend of Huxley and a Darwiness who then turned on Darwin and later the Catholic Church. And he was excommunicated by everybody, right? But in the interim, he was one of Darwin's great critics. He was criticizing of what would happen during the great transitions in evolution? You know, what good is 5% of a wing in a bird? Can you really have, you know, transitional stages that mean anything? Moreover, he said, if you think about the number of different kinds of changes that have to happen in any great transition, whether it's the origin of birds or the first fish that walk on land, there are so many features that have to change, you know, in sync, that they'd be impossible. You know, if you think about fish walking on land, you have to have arms and leg, wrists, you have to have lungs, you have to have necks, and that's just the tip of the iceberg. If you think about the origin of birds, same thing. if they have hollow bones, hypertabism, feathers, wings, and so forth.

If all those have to evolve at once, then evolution would soften its tracks, right? But, you know, he brought out the best in Darwin. So he brought these criticisms up after Darwin's first edition of the origin of species in 1859. But then Darwin actually added a whole chapter, which responded largely to Mabart in his sixth edition, which is considered the main one, most reliable one. And it was a remarkable thing that he did because he was in response. He came up with one of those great ideas. Right.

Yeah, and he really distilled it down into this one idea about a change of function. Yeah, exactly. What he said is much of evolution is not necessarily the origin of new features, but a change in function of features that already exist. That's huge because what it means is evolution doesn't have to wait for the origin of new features. You could just repurpose features for new functions. And the example that Darwin actually started to use. And that was if you look at sort of the invasion of land by fish,

from fish that walk on land, you'd say, well, lungs, they had to come about. The reality is they didn't. That as lungs were present in fish for eons before the first, you know, fish took steps on land. Lungs originally rose in fifth, you know, as an accessory respiratory organ, along with hills, to allow them to breathe air when the oxygen supply in the water just wouldn't cut it. You know, and there are other features like that as well. If you think about feathers and berbs, you know, you naively associate that those are associated with flying, that they arose to help, you know, the ancestors and birds fly.

But that's not the case at all. They originally rose in theropod dinosaurs, which weren't necessarily flying animals, but they were extensively reused for thermoregulation, some sort of insulation, or going to court ship displays or what have you, but it wasn't flight. And so, you know, so if you think about, you know, if you think that, you know, lungs arose to help creatures walk on land, legs arose to help creatures walk on land, the feathers arose to help creatures fly. You'd be in good company, but you'd be entirely wrong.

And we've known a lot of this since Starlight. And so, you know, when we think about evolution and natural selection, it's about responding to the environment. But, you know, this happens on a smaller scale. You say that genomes are at war with themselves. What do you mean by that? Oh, yeah. I mean, there's a war going on inside of this all the time. I mean, it's pretty remarkable that there are, if you look in our genome, and this was discovered by another scientist.

I just loved telling her stories, Barbara McClintock, who discovered jumping genes. There are different kinds of them, but basically what they do is they make copies of themselves and then jump around the genome. They're almost a selfish kind of DNA that left to their own devices will make copies of themselves and just proliferate across the entire genome. And if you look at our own human genome, you know, about two-thirds of our genome are these jumping genes that have sort of taken over. But the reality is we live in a balance with these jumping genes.

That is, there are mechanisms, some of them not very well understood, that our genes, and physiologies to limit their jumping, otherwise it would kill us. Because what happens is these genes can jump, and it all depends where they land. In some cases, they can land in the middle of another gene, in which case they would knock out its function and can be dead or harmful to the organism. But in other cases, and we're seeing this again and again, is these genes can jump and then land in a place where they can activate genes in new ways that can itself be fuel for evolution. And we're seeing that in the evolution of pregnancy, for instance, some of the aspects of pregnancy.

So it turns of it be fuel for evolution. And one of the things that I was surprised to read, like some of the fuel for these genomes are viruses. And like you said, viruses are involved in the development of human memory and pregnancy? Yeah. I mean, this is really surprising. And most people don't realize this because obviously we're living in an age of viruses. But we have this very complex relationship with viruses over hundreds and millions of years. If you look at our own genome, you know, only 2% of our genome is composed of our own genes.

You know, the part of our genome that encodes for proteins. The rest of, you know, it has lots of different functions. It turns out that 8% of our genome, 8, 4 times more than our own genes, are as ancient viral genetic material that somehow entered our genome. Turns out of some of this has been put to work. And it was seen in a study out of the University of Utah by Jason Shepard, a neurobiologist there. Jason was working on a gene that serves in memory in mice and people. It's called ARC. And he looked at the protein of arc and copped it under a microscope.

And he looked at it and he says, man, I've seen that before. Where he saw it before was in a microbiology class when he saw a slide of HIV, the virus of causes AIDS. In the building next story, he said, hey, I got a slide to show you. And he didn't tell him he was on the slide. And they looked at it and they're like, hey, that's HIV, the virus of causes AIDS. It's like, yeah. And so they got to work on it. It turns out that parts of ARC are repurposed virus.

And what happens is, so when HIV, the virus that causes AIDS, moves from cell to cell to cell, it makes a capsule, which protects the genetic material, which facilitates the safe travel of the genetic material from cell to cell to cell. So it does its work. Well, ARC does the same thing. It forms a capsule, much like HIV. It's using that. And it moves from cell to cell to do its normal function. So it turns out that this viral function has been put to good use in repurposing for a memory gene.

for it to allow its material to move from cell to self. Wow, that's amazing. And mind-blowing. It is mind-blowing. And there's a protein or a set of proteins involved in pregnancy in the placenta that these are also repurposed viruses. The hypothesis is that sometime in the distant past and one of our ancestors, there was a virus that invaded the genome and that somehow that virus instead of sort of infecting, it was

later repurposed, was domesticated, if you will, to a new function, to rather than harm to help. to put to a new use. So viruses can be fueled for evolution. And that's one of the more remarkable recent discoveries in molecular biology. And some of the research here said some really interesting and beautiful ways to try and understand these questions. One of them that popped out for me was Sissumu Ono used paper cutouts of chromosomes and translated genes into music. How did you do that? Yeah, Ono was a gene. And Ono is famous for the theory that the way new genes can evolve, one of the main ways new genes can evolve is through duplication of copy. So one of the big

mistakes that can happen, you know, when cells divide, is you can end up with extra copies of genes. And so he said, well, that could be a major mechanism of evolution because if you have extra copies of genes, you had all that redundancy, you know, genes can evolve new functions in new ways. And he turned out to be profoundly right. But the way he got to this, he wasn't working at a time of high technology. He was trying to understand how many, what's the genetic material and how much genetic material exists in different species. So to do this, he had pictures of the chromosomes of different species that he took under a microscope, and he would blow those pictures up to the correct scale, and then cut them out and weigh them. So he'd weigh all the chromosomes, his cardboard cutouts

of the chromosomes, say, of a rhinoceros. He'd weigh them and compare them to cardboard cutouts of the chromosomes of, say, salamander. And you'd find, wow, the salamander has much more, you know, much more genetic material inside itself than be rhinos or other creatures. Turned out to be a really profound set of experiments. I mean, here he's making paper doll equivalence of chromosome. But what he discovered was that the complexity of an animal does not relate to how much genetic material it has inside the cell, which at the time he was working in the 50s, that's a pretty big deal. In 50s and 60s, that's a pretty big deal.

And that's something that was only later confirmed by the genome project. you know, in the, in, since 2000, where we find that, you know, creatures, you know, we humans have about 20,000 genes. There are some creatures like lilies and frogs and samuers, which have much more genetic material. So the complexity of an animal doesn't necessarily correspond, you know, to the amount of genetic material in itself. And the insights into that were first seen when, you know, Ono cut out, cardboard cut out

the chromosomes and cells. But he had another hobby. He was a musician. And so what he did is he looked at the amino acid structure. proteins, which was becoming known in the 1960s, you put a different note for a different for each amino acid inside the genome, and he compared the scores he would get for proteins of different species. So we'd get the score of a protein, you know, in a mouse and compare it to the protein

in a salamander, and you'd have these tones, the tunes that you could listen to. You know, they're on YouTube. You can listen to them. Really? You can't listen to them. Well, yeah, you can't listen to them for long. They're not very tonal. Right.

Right. I think I'd be more inclined to have 23 and me done if I got a paper cut out of my genome. No, you got it. Me too. Yeah, me too. Definitely. What I like about kind of these biographies is that, you know, some of these scientists were very wrong in their ideas, but they were just as ververent and adamant about their ideas. I mean, why are the wrong turns so important? So wrong turns are so important in science. You know, when people put an idea out there that builds new, based on new data that gets us to think in new ways, that propels science often, whether it's right or wrong. And we've been propelled as scientists by wrong ideas. You think about, you know, Navarre with his wrong idea. Well, that propelled Darwin to greatness.

You know, and so, you know, it's not about being necessarily always being right. It's about using evidence to move the field forward. And oftentimes the fields move forward by, you know, by wrong ideas that have propelled other scientists in opposition, you know, to do much better. You know, and we see that unfolding in real time with the coronavirus research, you know, which every day you find in research, you know, that some some of its can do that, you know, conflicting. You know, but truth will out. Evidence will win the day, but sometimes wrong ideas do move the field very, very importantly. So, you know, that's why some of the people that I

talk about in the book were wrong, but they were right at the time. They were right with the evidence that they had. And so, and they thought about it in an important way. And it's only when we had new technologies that we can see, we're not fully able to explain what they thought they could explain. I'm Alex-LIM, and this is Science Friday from WNYC Studios. What are the big questions in evolutionary biology that are still unanswered or that you are particularly interested in? Well, one question I really love, and I think we still have to provide answers, and I think we now have the tools to do it, is why to some lineages not evolve much over millions of years and

others evolve dramatically? And by evolve, I mean, speciate and produce many descendants, others may not. You know, compare beetles to horseshoe crabs, you know, for instance. you know, why do we have thousands of thousands of species of beetle and relatively few species of horseshcraft? And that kind of thing. And I think understanding that dynamics of speciation, understanding, you know, diversity and why some things are more diverse than others, I think, you know, is something that we'll

understand those insights will come from linking studies of ecology to molecular biology to anatomy and so forth. You and your team found a fossil called Tictolic, which is something you called a fishapot and kind of shows a transition between water and land. that was 14 years ago when you just recently took a CT scan to it. What more did that CT scan reveal? Oh, it's fun. It's just giving us all kinds of new insights.

So we can scan inside these things. We see how the bones fit with one another. What we discovered is the skull is italic, you know, is highly mobile. It can open and close like a fish, but it can also bite. We put CT scanning, new CT scans on the fin. We can see how just how the fin is really built for walk and just support the animal. So surprising insights, you know, that, that follow what we did 14 years ago, because we can do anatomy now with new technologies that didn't exist 14 years ago.

And so paleontology itself has been changed by drone technology, by CIP scanning technology. You know, so it's not just molecular biology that's been compelled by technology. It's the, you know, it's working on the process of law. Thanks so much for joining us. Yeah, a whole lot of fun. Thanks. Neil Schubin is a professor of anatomy at the University of Chicago. His new book is Some Assembly Required, Decoding 4 billion years of life. from ancient fossils to DNA.

This is Science Friday. I'm Alexa Lynn. When we come back, we'll talk about Apple detectives, identifying pioneer-era varieties, sometimes with the help of watercolor paintings. This is Science Friday. I'm Iroflato. Just one quick note.

We're trying to figure out why people do citizen science or don't. And this means it's research time, so please help us out at ScienceFriday.com. slash citizen science. When you think about apples, don't you consider them to be a very American fruit, you know, apple pie? Well, maybe that's because North America once had 17,000 varieties of domesticated apples, yet only about a third of those still exist.

So where did they all go? Across the U.S., volunteer apple detectives are searching for those lost apple varieties. The Lost Apple Project in Washington State recently made a big announcement. They rediscovered 10 types of apples in the Pacific Northwest, some with far away origins. Here with us to talk about identifying lost apples are Sean Shepard, a palmologist at the Temperate Orchard Conservancy in Portland, Oregon, and Gail Vogue, plant physiologist for the USDA in Fort Collins, Colorado. Welcome both of you to Science Friday. Good morning, Ira.

Thank you. Nice to have you. How did such a variety of apples get to the Pacific Northwest, Sean? Well, there were a lot of mail order nurseries that sent stuff all over the country. And there were people that collected vast assortments of varieties and spread them out. There was a man in Illinois named Benjamin Buckman that had six or 800 varieties, which he sent out to people that wanted. to get different ones to graft and collect them. Was there ever really a Johnny Appleseed? Was that guy, perhaps, Johnny Appleseed? He was close. He disseminated a whole lot of stuff to a whole lot of people, apparently. Well, if we had so many of them, how do you lose so many varieties of apples?

Well, mostly people just forget what they are. You've got a homesteader, plants an orchard, and for whatever reason they quit and they leave the property. The people that come next may not necessarily know what they are or there's no people there. So you have these trees just standing there for a hundred years growing. There's still what they were to start with. It's just nobody knows what they are. We think that a great many of the varieties that are lost are simply lost.

They're out there growing someplace, but we just don't know. Somebody has to figure out what they are. So you mean they could be in somebody's backyard now when they bought a house with a tree in it and not even know it's one of these abandoned apple trees. Yes, definitely. Wow. Huh. Do we know why, then, that apples were the fruit of choice for these homesteaders?

Well, you can eat them, you can feed them to cattle. You can press them into apple juice and ferment hard cider, and you can distill that into brandy. It's a very useful fruit. I know you identified these rediscovered apples for the Lost Apple Project. Give us a couple of examples of the types of. apples you found and what you learned about their origins? Well, one of them was the Sari-Synap.

And it turns out it was brought from Turkey. That's where its origins are. There were a lot of apples brought by different horticultural societies across the United States at different times. This may have been in a batch brought by the Michigan State Horticultural Society in the 1880s. So they really came then from all across America? Well, all across the world, there's a lot of Russian apples here, too. So people brought them with them as immigrants and planted them?

No, no, these were imported on purpose by people who were interested in more strains of apples. They were interested in growing a lot of different things and seeing what would succeed, and they imported them because we didn't have them here already. That's interesting. So as you are working through the Lost Apple Project, you must find an apple you haven't seen before and take a bite at it. But what do they taste like? Apples have a huge variety of flavors from saccharine sweet or candy-like to as sour as a lemon. There's a vast array of flavors.

We found one that tastes like mint. We've never seen it in the literature. We haven't figured out what it is, but minty. They blew our minds when we tasted it. Wow. And you used watercolor paintings to help identify them. I find this so fascinating. How does that work?

Well, between about 1880 and 1939, the USDA employed watercolors to document apples. And they did true-to-life watercolors of apples that people sent in. So there exist about 6,000 of these paintings of apples. And some varieties have more than one. Some only have one. Some apples are only represented in literature by the watercolor. But apples very hugely, I mean, they come in all different colors and shapes and sizes and they ripen a different time. But if you find, we look in an apple and it looks like so-and-so.

Anyway, sometimes we can find this exact duplicate in these watercolors. And how reliable then is that method you say sometimes? Don't a lot of apples look alike? I mean, you... Yes, that's true. These watercolors must have been painted very accurately. They are very accurate. The fact, they're probably, well, they're more accurate than a photograph in some ways.

But we have to also search the literature. There were a lot of pomologists in the 19th century that wrote very detailed descriptions of these apples, all their characteristics. Without the detailed descriptions, it's much more difficult to just go by. a picture. Once in a while we can do it, but it has to be a really unique looking apple. So you're talking about a process that can take years? Yes. To bear fruit, so to speak. Yes, there's been apples that took me years to figure out what they were. Gail, the USDA uses a different method, right, to identify apples and other plants. Tell us about how that works. Well, USDA has a national collection of apple of ours and wild species in upstate New York. And we've been using genetic testing

to look at the DNA and identify or fingerprint all these varieties in our national collection based on the DNA fingerprints. And I guess DNA fingerprinting is a much more reliable method than watercolor. It's a genetic test. It's based on the data of the DNA. But you have to have the source of the genetic material in your lab, right? To compare it to. Right. We need to have those varieties available in our national collection, and then they serve as references for these varieties that be found on historical lands. Okay. I'll bite. How many apple varieties can the USDA identify right now? Well, we have about 2,500 trees in our permanent collection that are mostly domesticated cultivars. And I use about 1,200 of those in our genetic analysis.

So when you say their cultivars, the USDA is actually growing the apple trees? Yes. We have a field collection of apple trees in Geneva, New York, and it's part of our national gene bank system. What do you do with all the apples? Oh, the trees aren't grown necessarily for their apples. Sometimes they're sent off for researchers for projects. but usually the materials in the collection are used for evaluation trials. They're for genetic research, and they're also for distribution for research purposes. So they're not mature trees that are bearing fruit yet? Most of them do bear fruit, absolutely.

I can't imagine not having some of the fruits from those apples. But that's me. I know the USDA has a large collection of seeds and plant materials in Fort Kod. Collins, where you are, including for the apples here. What is, what is this collection for the whole collection? Why do you have that? Well, USDA has a collection that's maintained. It's called the National Plant Germplasm Systems Collection. And it's about 600,000 different accessions of crop plants that are important to American agriculture. So we maintain this as a distributed collection at around 20 different locations in the country. And we make them available for

breeders and for researchers for plant improvement primarily. Our facility here in Fort Collins, Colorado has about 530,000 accessions stored, mostly as seeds, but we also have things placed into liquid nitrogen as other plant forms as well. We've got over 2,000 apple cultivars stored in liquid nitrogen as dormant buds. Wow. I remember years ago when we first started talking about apples, and something I didn't know is that if you, if you're a lot of, you know, it's you eat an apple and you take the seed and you plant it, you're not going to get the same apple from that seed, are you? No, apples are grafted. That means they're vegetatively propagated. And the original apple tree for a given cultivar has been multiplied many, many times

their grafting process. Does this complicate it all then the DNA testing methodology? Actually, it simplifies it because every red delicious apple in the country has the exact same genetic signature. Is that right? Yes. So is that sort of a dangerous thing then if there's a blight that wipes out one kind of apple like we're seeing with bananas going on now? It could just spread across the country? It's certainly a possibility. The different varieties of apple do have some different genetic compositions. So there is some resistance built in. And that's a big effort for some of the breeding programs in the country to bring in new sources of resistance to possible future threats. I hear that you're part of a research team that's looking at potentially lost

apples in Yosemite National Park. Why there? What can you tell us about this project? We're working with Yosemite National Park to help them understand what kinds of apple trees they have in 10 old heritage orchards that were planted between the 1850s and the 1890s in the park. We've tested over 361 trees that are currently. in Yosemite and helped them understand what varieties they have and which trees could be targeted for future protection efforts. Sean, do you ever leave the Portland area and go like to Yosemite to look for some apple trees? That'd be great. We've gone all over the state of Oregon and different places in Washington looking at orchards here and there. You know, it's interesting about apples and

apple preservation, conservation, between both of you, because you don't hear about this level of excitement for rediscovering varieties of other fruits or vegetables. What do you think it is about apples, Gail and Sean, that gets people so impassioned? Well, apples are the quintessential American fruit, and there are a huge number of varieties, and over time, interest is building and has been building for the last 50 years. there's been different individuals that have been doing some of this work. And partly it's due to efforts to publicize this effort.

Are there other palmologists? And I think, I guess the word palmologist, Latin palm fruit, right? Yes. Are they also working across the country or in other countries to discover orphan apples like you are? Yes, there are people all over the world doing the same thing. We have some friends in Great Britain that are very interested in this sort of thing. I'm Ira Plato, and this is Science Friday from WNYC Studios, talking with a couple of Apple specialists,

Sean Shepard, a palmologist at the Temperate Orchard Conservancy in Portland, Oregon, and Gail Vogue, plant physiologist for the USDA in Fort Collins, Colorado. Do you ever have a, you ever go to an art museum or talk to art conservatory people and say, Hey, look, if you ever come up with a painting that has apples in it, wherever it is, I want to see it. Yes, I take special note of apples in paintings. I was in Rome a couple of years ago and I was like, look at that. That's the same apple in that painting and that painting over there. And eventually I figured out what it was.

You probably drew a crowd of people, I think, too, when you were doing that. Nobody noticed. Well, what would you like to do? if you had resources, Sean, to expand what you were doing, if I could give you a blank check, you know, and say, here's some money to collect some more information. What would you do with it? Partly what needs to be done is the purpose of the temperate orchard conservancy

was to reproduce Nick Botner's collection of 4,500 varieties. We probably have 3,500 to 4,000 varieties in our collection now. What needs to be done is we need to try to, verify what the names on those are correct because we know that many of them are wrong. We know that some of them are wrong in the Geneva collection that the Gales referred to. So that's one of the main things that needs to be done. We also need to have a clearinghouse of information about what varieties exist and where. It's very difficult to figure out whether an actual Apple is actually known to exist or not because

there, you have to check, you can check several major lists. but that there's a lot of a lot of collections all over the country that nobody knows what's in there. Well, maybe you'll hear from them after we broadcast, and you'll get some, hopefully, you'll get some information and some great backfeed. I want to thank both of you for taking time to be with us today. Sean Shepard, a palmologist at the Temperate Orchard Conservancy in Portland, Oregon, and Gail Vogue Plant Physiologist for the USDA in Fort Collins. Thank you both for being with us.

today. Thank you, Ira. Thank you, Ira. You're welcome. Want to learn more about the Lost Apples Rediscovered by the Lost Apple Project? Go over to our website, ScienceFriiday.com. There you can look at the USDA's watercolor paintings for the Sarisinnep of Turkey, the Butter Suite of Pennsylvania, and Clarabelle of Washington. These are the paintings still used today by Apple detectives like Sean Shepard. Check them out. They're really beautiful. I just want to take a minute to remind you of the importance of public radio during this critical time. As stations navigate changes to workflow and resources during the pandemic, they are doing everything possible to deliver you the news. And we're doing the same here at SciFri, because, well, not doing that, it's out of the question.

So please don't forget to support your local station. They need you now more than ever. And a special thanks to those of you who have donated to SciFri, we can't continue without you either. Thanks. And that's about all the time we have for today. If you missed any part of this program or you would like to hear it again, ask your smart speaker to play Science Friday. Every day now is Science Friday.

And don't forget to check out our latest podcast Science Diction. Host Johanna Mayer explores words and phrases and the science stories behind them. And there's a really good one this week. This week's episode covers the origins of the name Spanish flu. It's not what you think it was. You really don't want to miss it. Say hi to us on social media, Facebook, Twitter, Instagram, email us. We're all over the place.

You can email us at SciFri at ScienceFri.com. Send us your feedback. We'd like to know what you would like us to cover. Have a safe weekend. I'm Ira Flato.