Science Friday - Identifying New Plants, And The Scientific Secrets Of Superfoods

Episode Date: May 14, 2025

What does it take to create and maintain one of the largest repositories of botanical information in the world? For starters, it can mean helicopter-ing into remote nooks of the Amazon, hiking through rough terrain, looking for strange fruits and flowers, and climbing trees to pluck specimens from the branches. Then there’s all the science required to identify, classify, and codify those species. Botanists Lúcia Lohmann and Charlotte Taylor join Host Flora Lichtman to discuss their work discovering new plant species and maintaining the storied Missouri Botanical Garden.And, what does it mean to be a superfood? What is the science of micronutrient-dense foods like millet, which get less hype than foods like açaí, goji berries, and quinoa? Flora talks with biological engineer Kiruba Krishnaswamy, who puts food under a microscope—literally—and studies the nutrients that help make our bodies function, in hopes of harnessing them to fight hunger worldwide.Guests: Dr. Lúcia Lohmann, professor at Washington University in St. Louis, and president and director of the Missouri Botanical GardenDr. Charlotte Taylor, botanist and senior curator at the Missouri Botanical Garden Dr. Kiruba Krishnaswamy, assistant professor in the Colleges of Engineering and Agriculture at the University of MissouriTranscript will be available 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.

Hi, this is Flora Lixman. You're listening to Science Friday. Sifright just got back from Columbia, Missouri, where we did a live show with the radio station, KVIA. So today we are bringing you to Mizzou's Jesse Auditorium to dig into the wild world of plants. From the microscopic nutrients they pack to the quest to identify every single plant that lives on planet Earth. To figure out how our world works, we need to know what these are and where they live. One of the great mysteries of our planet is simply what lives here. It's a deceptively simple question, and it's the life's work of my next two guests. They've spent their careers in the field looking for new plant species.

If botanical work conjures up an image of someone in a wide-brim hat with gardening gloves in a spade, think again. What this work actually requires is health. helicoptering in to remote nooks of the Amazon, hiking through rough terrain, looking for strange fruits and flowers, climbing trees to pluck specimens from branches. And that's just step one. Then there's all the science required to identify, classify, and codify those species, which my next guests do at one of the largest repositories of plant information in the world, the Missouri Botanical Garden. Here to tell us more about this work and why it's important is Dr. Lucciproven.

Lohman Professor at Washington University in St. Louis, and President and Director of the Missouri Botanical Garden. She is the first woman to hold the post. We also have Dr. Charlotte Taylor, botanist, and senior curator at the Missouri Botanical Garden, who is recently named the most prolific woman author of new plant species living today. So we have some living legends with us. Thank you both for being here, and welcome to Science Friday. Thank you so much for having us. So you're both in the taxonomy business, finding and naming species. Lucia, why is it important to give plants names? Well, if we think about it, imagine if we don't know the names of different species,

we can't even know what they are, right? So I always say that knowing the names of plants is the first step for conservation, for studying them in the same way that knowing how to read is the first step for education. I mean, Charlotte, you've named more species than any other living woman. Living. Living. Keep that in mind. Even so, it's pretty cool.

What's your perspective on this question? Once we have the name of a species and know what it is, it's an index to everything we know about it. Everything everyone studies about the chemistry, the policy, the policy. and conservation. It's all linked to that name. You need to name it to know it. Exactly. Lucia, you've studied the Amazon Basin for most of your career. Why there? Well, if we think about it, the Amazon Basin is like the most species rich biome in the world. And if you go there, you would instantly understand why. Tell us about it, yeah.

You walk around and every day you see a different fruit, a different, flower and all kinds of things and imagining that plants are really the foundation. They are the reason why we exist without plants. We don't have oxygen and we don't exist. I mean, when you say it's biodiverse, how does it compare, you know, species-wise to a place like Missouri? Well, so if we think about plants, the Amazon basin, we imagine that we have around 40,000 species. In one hectare of Amazon rainforest, we have more species of plants than we have throughout Europe, for example. In one hectare, which is how big is that?

100 by 100 meters. 100 by 100 meters, more species of plants in the Amazon than in Europe. Yes. That's amazing. And not just plants. I mean, it's like millions of species of insects and 1,300 species of birds, 3,000 species of fish. really high biodiversity every organism you look at. Why? Why is that true there?

That's the million-dollar question, and that's exactly what I've been studying during the past few years. So we really, in order to understand this huge puzzle of how did this high species diversity emerge in one particular region, what we do is to go out in the forest, to catalog the species,

and then we build evolutionary trees that are essentially like genealogies. And then we use that information to combine with the geological history of the region to then really recover the patterns and the processes that led to this high species diversity. And so in the Amazon, one key driver is, for example, the river drainage.

So if we think about how these species formed, right? So you have one population, at one point, you have some kind of separation, sometimes could be a mountain range. Two populations are separated. They start to accumulate differences over time, and then you have two species. So in the Amazon Basin, you have lots of rivers that separate populations that lead to high species diversity.

I want to hear a little bit about how you both got into this field. Charlotte, let's start with you. Where did your interest in plants begin? Well, I grew up in a family with some people who discovered amateur birding and got into it. And they took us with them, whether we wanted to get up at 4 o'clock in the morning or no. We went along with them. And we grew up looking at nature. And also, I grew up in a somewhat rural area, so we were outdoors all the time. Everyone in my town and the area was outdoors all the time, and it just seemed natural. And you paid attention to the

world around you. And I love plants. I found a passion for them, and you don't have to get up at 4 o'clock in the morning. That's a good reason. What about you, Lucia? Well, also since I was a child, so I was born and raised in Brazil, and I was surrounded by biodiversity, and it's kind of funny,

because when I think about going out and playing with my friends, it always involved plants. And so I started to just pay more attention, to grow my own plants, and eventually became a career. And you have some botany in your family history, right? Well, my great-great-grandfather, he was a chemist, actually,

but he became the director of a botanical garden in Indonesia, which was really kind of fun. I would love to go in the field with you. I wonder, can you give us a little bit of a flavor of what that's like? Like how you get there and what a day is like. Yeah. So there's different types of. of fieldwork, some of the most pristine places that we go, sometimes you have to hike mountains

to get there or take boats for days to get to particular places where we want to collect. And in the past years, we've really been trying to go to places that nobody had collected before, so we really bring new biodiversity. And a day in the field is essentially, we wake up really early in the morning, and we get all our materials ready, and we start to walk in the forest. and looking for plants that have flowers and fruits. And sometimes they're very high up in the canopy, so that entails climbing up 50-meter trees to collect them

and bring the flowers and fruits down. So essentially we go out and we grab little branches of different species, and we press them in newspaper. And then we put them in a plant press. This is our 1600s technology that we still use to make dried plant specimens. We write all kinds of information, the color of the flowers, where did we collect, the conditions, and so forth. And then we smash them, and we later bring them back into the museum, and we dry them and keep them. So this way our museums have species from all over the world.

Charlotte, how do you know what to pick? I mean, if you have all of these different species around you, how do you know which ones to bring back? If I go out in Missouri or the Gulf Coast of America, I would pick something I didn't recognize or something that looked interesting that I wanted to study. When I go to the Amazon, I don't know what anything is, so I just take one of everything. It works. And what we do is we bring it back in big boxes, and then we spend about two years figuring out what it is. And that's what the Missouri Botanical Gardens Research Facility is for.

We have reference specimens, we have the library, we have internet access, and we have visitors who come through all year from all over the world, and each one of us knows a tiny little portion of biodiversity. Why does it take two years? Because there's a lot of plants, and no one knows what they are, because there's a certain entry point where you have to figure out where to start identifying a plant. We put them in families and we put them in genera. But when you get down to the level of species,

in order to find what it is, you have to either match it up with something else, which is not always easy. Or if it's new, then you have a real project. And in the Amazon, a lot of them are new, but to just figure it out, you have to eliminate every other possibility. So it's like you prove a negative,

but it takes a lot of time. So, you know, I want to talk a little bit more about why it's important to catalog all of this biodiversity. So where does this take us? I started out as an ecologist. My idea was to study how a community was put together and what plants live there and why some are successful. And then I discovered that no one could identify half of them. So how can you say what grows there if you don't know? And so I started working back and back to identify stuff.

And when I put a name on something, then observations from forestry, from chemistry, get connected. And the next important step is then you can use it to restore damaged ecosystems because you know what lives there. One thing that people don't usually realize is that there's still lots of species out there that we don't even know their names. So for the Amazon basin, for example, we estimate that only 10% of the species, have been named. 10%? So 90% of the species, we don't even know what their names are. Every single trip I do to the Amazon, we come back with dozens of new species.

Really? And if we think about, so overall, we have 350,000 of antelisperm species, so flowering plants that have been named, and lots more still to be described. And for other organisms like fungi, for example, we estimate that, we're probably going to need a thousand ears to describe all the species that are out there. So for fungi, it's even, I think, only maybe 5% of the species have been described. But to figure out how our world works, we need to know what these are and where they live. I love it.

This is Science Friday from WNYC Studios. Let's go to the audience right here. Do you have a question? I'd love to hear a little bit more about the social and cultural interactions that you have when you go out into the field. particularly given that people are living in these spaces. So what does knowledge exchange look like in these fields? That's such a fantastic question. And I feel like every time I go into the field

and I meet people from the local communities and so forth, I always feel it's such a lesson of humility because we've been doing master's, PhDs, postdocs, and studying the plants, and then you get there, and you realize you don't know anything. Like the local communities, they really have such a, deep understanding, not just the names, and these are the names they give to those plants, but they are uses, their properties, how they grow, and all kinds of things.

So we learn a lot from them. And we try to give back as well. The local communities are always involved in our projects. They always go with us, and we leave behind what we can, depending on what they want. They don't always want specimens or something. I was going to ask about that because I know in paleontology, you know, that field's changed a lot. People do not go to other countries and bring back bones, right? But that's how it used to be.

How do you think about that now in botany? I mean, dinosaur bones obviously different from a botanical specimen, but I'm wondering if that thinking has evolved in botany too. Yeah. Well, things have changed, and it's true. In the past, people used to come, collect specimens. And in the past, there were no herbaria in a lot of the countries where people used to go collecting. And so nowadays, what we do is always the exchange and always making the information available to everyone. So, for example, right now at the Missouri Botanical Garden, we are starting a project to digitize our 8 million specimens that will be freely distributed to everyone.

And we really want to make the information available in formats that is just not for, for scientists, but anybody interested in plants, they can take most advantage of the information. Let's go back to the audience over here. Do you have a question? We're talking about the canopy and the Amazon. So are there different plants at different levels? You have to keep looking for different plants depending upon whether they're at the top or near the ground. Excellent question. And so I actually, well, the way we bought in this Divide our work, we have a family that is our favorite, right? And my family... A group of species.

Exactly. So a family of plants that usually 1,000 or 2,000 species, the family that I work on, my group of plants, they actually grow in the canopy. So they are climbing plants and you only find them in the canopy.

In the Amazon basin, the river can change 30 meters. So we try to go when the river is high up and then you just go in a little boat and then you just grab those species without having to be.

to plant. It's true. It's true. Go ahead. You have a question over here? What's your favorite plant you've ever cataloged? Ooh, that's, well, I can give some examples and be here all night, but I'm going to say that finding an undescribed species, a new species, and naming it, it's like your kids. So that's like asking which is your favorite kid. You can't really say which is your favorite. Some of them are prettier than others. Some of them, you know, are kind of more interesting than others. But I like all of them. Before we wrap up, is there one thing you want the audience to take away? You know, when they think about plants, what should they think? Well, the first thing is really plants are the foundation, really, and just keep in mind the medicines, the clothing, and everything we do.

and try to learn names of plants. It's really kind of amazing. If you learn the names of five different species, you will walk around, and again, it's like your friends. You're going to see them and see what your friends have to offer, flowers and fruits, and it will really change your life. If you try a few each week, you will see the result. Charlotte?

I would say that I think that a scientific cataloging, is really dull and is considered unexciting, but it's the basis for everything. And what you don't see up here with the two of us sitting is that this is a team activity. We are not here on our own. We did not get here on our own. We are here because of all of our colleagues in different countries and a whole lot of interested amateurs and don't assume that you can't be as interested in plants in as good as we are. I'm just going to just quibble with one thing. It's not dull. It's definitely not dull. Would you guys agree? Dr. Lucia Lohman, professor at Washington University in St. Louis

and president and director of the Missouri Botanical Garden and Dr. Charlotte Taylor, botanist and senior curator at the Missouri Botanical Garden. Thank you both for coming on the show today. After the break, what are micronutrients and why did they matter? Hidden hunger is due to people might consume food that are calerific dense, they are missing the required vitamins and minerals. We are constantly hearing about the latest, greatest superfood. Goji berries, assayi, quinoa.

But what does it mean to be a superfood? Is there any science to it? My next guest puts food under a microscope, literally. She studies the nutrients, the microscopic molecules that help make our bodies function. And she's trying to harness them to fight hunger. worldwide. Dr. Kuroba Krishna Swami is an assistant professor in the colleges of engineering and agriculture at the University of Missouri, and she's based right here in Columbia. Please welcome her to the show. Thank you for us. Welcome to Science Friday. Okay, is there any science to this idea of superfoods?

Are there foods that have more going on nutritionally than other foods? There are some foods that inherently have health benefits like immune boosting properties, brain development, antioxidant properties. They could be high in vitamins and minerals. So these foods can be categorized as superfoods. For example, elderberries, they have those polyphenolic compounds, the antioxidant property that gave those immune boosting properties. Okay, so you study micronutrients. What is, What is a micronutrient and how's it different from like a regular old nutrient? So when we talk about nutrients, we talk about macronutrients and micronutrients. So imagine a puzzle of a map.

So we have big pieces and we have small pieces. So big pieces like proteins, carbohydrates, fats and small pieces like vitamins and minerals. So when you're putting this map together, we need to have both the big pieces and the small pieces together. If even a small amount of these micronutrients are missing, then the body might not be able to metabolize the larger pieces, like the proteins and so on. Do we typically get enough micronutrients in our diet? No.

No? So dietary diversification is when we are able to consume. a diverse variety of fruits and vegetables and foods. But how many of us can say that we can have a balanced diet every day? I eat only cheese, so I cannot. So same, right? It's difficult to have a diverse diet every day. And that's where supplements come into play.

So most of us might take vitamin supplements and so on. And that gives required micronutrients. On the other hand, we could fortify them with foods that we commonly used, like the bread is fortified with folic acid and B complex, like the milk is fortified with vitamin A, vitamin D. Salt that we consume is iodized. So we can fortify them, so when we consume them, we get the required micronutrients.

Is there a food that has a lot of micronutrients that you feel like is underrepresented in people's diets? It's like a superfood you'd like to see go viral. So one food that I really like is millets. It's because millets, these are ancient grains. And when we talk about millets, we always think it grows in Asia and Africa. But I was surprised to see that it also grows in the Midwest. It's sometimes called Milo.

It's drought tolerant. And it's also nutritious because it has high fire. high vitamins, minerals, and a good amino acid profile. So that's one food I feel like it needs to come back. I read that 2023 was the year of the millets, which I can't believe. I didn't celebrate, and I feel like I missed out. Did you celebrate? Yes, we did celebrate.

And Missou hosted a webinar series throughout the year for expanding millets. You celebrated with a webinar. Yes. So I heard your lab was the first to get images of millet under an electron microscope. Is that right? Yes. We were the first research group to put these millets under the microscope to see their structures. When we look at the millets, they all look small.

They're small, but they're different. Like some are green, some are sort of a deep purpley red, others are a little bit bigger. Yes. And they're beautiful to look at. If you have a question for Curibu, please come up to the mics and we will get to you shortly. So I understand that you worked on a way to use millet to add micronutrients to our diet and also tackle food waste, I think. Will you tell us about this project? So when this particular project came to us, it's a Greek yogurt processing.

For every one cup of Greek yogurt, we generate three cups of waste. and this waste is high in calcium and so on. It's currently distributed down the drain, used as a fertilizer, it causes an environmental problem, algal bloom, and so on. So when we got this challenge from the industry, how do we address this food industry waste, we thought, okay, we have some unexplored millets, why don't we combine them,

and we could formulate it in our lab, And we were able to generate powders that are really nutrient-rich. And then what do you do with them? Like sprinkle it on popcorn or what happens next? So these powders can be used as supplements, and they are mineral fortification agents, infant formula development, and they have a multiple application process for this. Fascinating.

Let's go to the audience. We have a question over here. What's the best way for a kid to get micronutrients? What's the best way to get micronutrients is, so when your mom says eat all your greens, just consume them. They are so yummy and they will give you all the required micronutrients so you can become hail and healthy, your brain power, immune system, your physical growth, everything will be strong. Do you eat leafy greens? I do.

I'm really into vegetables and I eat them a lot. Good job, yeah. Thank you. Go ahead. Another question from the audience. Thanks. So my question is, for example, you were mentioning millet. Do you have like a specific cookbook in mind or a specific strategy? How do you make people consume millet if they have never used it before in their kitchens? That's a very good question.

It's because we could have the product, we could develop these new varieties. but if it's not culturally appropriate, if it's not region-specific, then acceptance of this food will come difficult. So whenever we develop a product, we need to understand the population. What needs are we meeting in that population? So developing it with the people,

and that's when we can have products that can be accepted. Tell me, are there other foods besides Millets that you're sort of, you know, desperate to see, go big? Yeah, there's so many foods. We work with poppaws. Pop-au's are the large... We've got a lot of Paw-Paw fans here.

So, Pop-Boh is the largest Native American fruit that has tropical flavors growing in temperate regions. And we were able to increase the shelf of pop-a fruit from five days to 15 days. You know, one of your lab's goals is to tackle global. hunger. Why did you decide to go, you know, microscopic to help solve this huge problem? So when we talk about hunger, we always talk about chronic hunger. That affects more than 821 million people. So in 21st century, we should not be talking about hunger, but unfortunately

we are. And hidden hunger is as dangerous as chronic hunger. It affects more than 2 billion people. That's roughly one-third of the global population. Will you define hidden hunger? Hidden hunger is due to people might consume food that are calerific dense, but they are missing the required vitamins and minerals. And that can lead to series of health problems from cognitive development, physical development, immune system. So that's why it's called hidden. We assume that we are getting food, but we are missing those key micronutrients that can be an enzyme or a co-factor for other metabolic processes. And whenever we talk about hunger, we always think stunting and wasting.

Imagine an umbrella, right? On one side, we have stunting and wasting. On the other side, we have overweight and obesity. So all these things fall under the same umbrella. and this is what we call the double burden of malnutrition. So this is on one hand. On the other hand, we waste around 1.3 billion tons of edible food annually.

That's a lot of food, right? And most of that is fruits and vegetables because they are perishable, their shelf life is short. And they are the high source of vitamins, and minerals too. So if we can come up for solutions that instead of that going as waste, we can recover them. Because in nature, there is nothing called waste. It's a terminology we humans have created because we don't know how to process it. And why I looked at this, the micros is because there is no single bullet to solve this complex problem, but everyone can contribute

and we all eat food, like it connects us, right? If we can send man to the moon, right? If we can have technologies to send humans to Mars and the scientific advancement, then we can also imagine a world where every child born on this planet can have access to safe, sufficient, and nutritious food. I think that's the perfect place to leave it.

Kirovha Krishnaswamy, assistant professor in the colleges of engineering and agriculture at the University of Missouri, Columbia. Thank you so much for joining us today. Thank you, Florida. And that is about all we have time for. Lots of folks helped make the show happen, including George Harper, John Denkoski, Annie Niro, Jason Rosenberg, Rasha Eredi. I'm Flora Lickman. Thanks for listening.