Virtual Science Café: Plant Conservation, The Origin of Earth’s Atmosphere, and National Parks of the Oceans

Virtual Science Café: Plant Conservation, The Origin of Earth’s Atmosphere, and National Parks of the Oceans
Air date: April 8, 2021

Naimah Muhammad:
Hello everyone. Hello and welcome to today's Virtual Science Café program presented by Smithsonian's National Museum of Natural History. We're going to get started in a moment, but my name is Naimah Muhammad, one of the public program coordinators at NMNH.

Amanda Sciandra:
And I'm Amanda Sciandra, another public program's curator at Natural History and together we'll be your host for this event. Whether this is your first time joining us or you've attended before, we're so glad to have you here. And although we can't see you, we want to feel your energy so please let us know in the Q&A box where you're tuning in from. You can see that box at the top or bottom of your screen and we'll try to get to as many questions during the event as possible. But for now, if you want to write where you're tuning in from, we'll call you out.

Naimah Muhammad:
Awesome. So we'll keep an eye out on that, but we just want to give a big shout out and a thank you. This series was developed with science communication resources generously provided by Smithsonian Regent and former museum board member, John Fahey, and his wife, Heidi Fahey. And it's offered with support from the Selig-Krichbaum Endowment.

Amanda Sciandra:
Our sincere thanks to them for making this possible and to all of those who support the museum's mission and outreach. It looks like we have some people tuning in from Santa Cruz, California, someone from Chicago, from Kettering, Ohio. Very exciting. Thanks guys for using the Q&A to let us know where you're tuning in from.

Naimah Muhammad:
And welcome and thank you for being here. Again, we also want to thank local D.C.-area restaurant, Busboys and Poets, who are our restaurant collaborator on this series. And if you saw, and I hope you had a chance to take advantage of the discount code for online ordering for the program duration. And we also sent a mocktail and cocktail recipe provided by Busboys and Poets themed around this event and there'll be one more and upcoming in May, so I hope you take advantage of it then.

Amanda Sciandra:
So before we turn it over to our guests, just a few housekeeping notes. We have three incredible speakers who will present back to back lightning style talks and then answer your questions during the second half of the hour.

And the Q&A goes by so fast, so please help us answer as many questions as possible by submitting your questions as you have them throughout the whole program and then right after each talk as well. And, again, that Q&A box is at the top or bottom of your screen. And if you could say who your question is for, that'll help us even more.

Naimah Muhammad:
Yes, perfect. Very helpful. Okay, so our first speaker is Jonathan Tucker. Jonathan Tucker received his Ph.D. in Earth and Planetary Sciences in 2016 from Harvard University and then he moved to Washington, D.C., to work as a postdoc at the Carnegie Institution. In October 2020, he became a Peter Buck fellow at the Smithsonian and he's now here where he does his research today.

His work involves analyzing and interpreting the chemical compositions of volcanic rocks, especially the gases trapped inside them. At the Smithsonian, Dr. Tucker is using measurements to study the process occurring during volcanic eruptions, how gases cycle through Earth's interior, in the origin and evolution of Earth's atmosphere. So now to tell us more, please, please join me in welcoming Jonathan Tucker to our virtual stage. Hello, Jonathan.

Jonathan Tucker:
Hello.

Naimah Muhammad:
You're so excited to have you.

Jonathan Tucker:
Well thank you, Naimah, for that great introduction.

Naimah Muhammad:
Perfect. So we will let you take it away from here.

Jonathan Tucker:
Thank you. Breathing is one of the most fundamental things that we do as humans, but it's also one of the most fundamental things that our planet does. Earth's breathing is the exchange of gases, or volatile elements and compounds, between the Earth's interior and the exterior. These volatile elements and compounds like water, carbon dioxide, nitrogen, noble gases in the exterior, they constitute the ocean and the atmosphere which are critical to making the surface habitable.

But have the ocean and the atmosphere always been there? How did they form and how did they evolve through Earth history? How has the exchange of volatiles between the interior and the exterior affected each? To answer these questions, we have to understand how Earth breathes.
So one example of Earth breathing is the exhalation of greenhouse gases like carbon dioxide into the atmosphere from volcanoes. This graph shows that changes in the amount of greenhouse gases, like carbon dioxide, have a big effect on climate not just today, but throughout Earth history. The green axis is how much carbon dioxide there is in the atmosphere and the yellow axis is the surface temperature, and you can see that they change in lockstep with each other for hundreds of thousands of years. So this is just one example of Earth's breathing affecting surface conditions.

But in terms of the whole Earth system, does Earth really care what the atmosphere is doing? The atmosphere is just a tiny fraction of the Earth. It's just 1,000,000th the mass of the Earth. Just how small is that? The mass of the atmosphere relative to the entire planet is like four points in Seurat's "A Sunday Afternoon on the Island of La Grande Jatte." Or it's like the word Horcrux on page 612 of "Harry Potter and the Deathly Hollows" relative to all the words in the entire series.

Another way I like to think about it is that it's like this mouse sitting on the elephant's trunk. The elephant doesn't really care about the mouse. If the elephant wanted to just flick its trunk, the mouse would go flying. The mouse is completely at the mercy of what the elephant wants to do. So really in order to understand what the mouse is doing, why it is where it is, how it got there, we really have to look at the elephant, that is the Earth.

And volcanoes are the means by which the elephant flicks its trunk. Volcanoes are the major interface where volatiles are exhaled from the Earth's interior to the exterior. Now we tend to think of volcanoes as this kind of occasional destructive nuisance that sometimes shuts down air traffic over Europe, but to an earth scientist like me, there's so much more than that. Volcanoes are one of the very few means by which we really have direct access to the Earth's deep interior and that's because material erupted from volcanoes originates from deep inside the Earth hundreds of miles below the surface.

So if we want to understand the volatiles coming out of volcanoes, we can go and measure them. Now measuring volcanic gases is heroic work and it takes people far braver than I am. This is not me in this picture, this is a colleague, Tobias Fischer. And people like him go all around the world compiling these measurements.

This map shows all of the volcanoes active in the past 10,000 years. These are cataloged by the Smithsonian's Global Volcanism Program. And you can see familiar features in this map like the Ring of Fire around the Pacific, the East African Rift, and islands like Hawaii and Iceland. So by measuring these presently active volcanoes, we have a pretty good idea of what's coming out of them, but we're missing a lot. This map is actually missing the Earth's largest volcanic system and that's where I come in. This is me standing atop the Earth's largest volcanic chain, but you can't see it because it's underwater.
These are huge volcanic chains called mid-ocean ridges which wrap around the Earth, kind of like the seams on a baseball. And these mid-ocean ridges make up, by far, the majority of Earth's volcanic activity. And in that last photograph, I was right about here in the middle of the Atlantic.

So if we want to measure the gases coming out of these underwater volcanoes, we can't very easily go and stick a probe in them. We can send a submersible down, but that's really difficult and expensive. So we can also do a cheaper alternative, a really low-tech alternative. We can go out on a boat and drop a big metal basket over the side, pull it along the bottom of the ocean for a little bit, and pull it back up and it comes back up full of volcanic rocks.
But we want to measure gas emissions, right, not rocks. Fortunately, volcanic rocks can trap gas as bubbles. And the process by which this occurs, it happens to be exactly the same as these bubbles rising through this champagne glass. The champagne's been depressurized, the cork's been taken out, so carbon dioxide that's dissolved in the champagne forms bubbles and they float up to the top. And this exact same thing happens inside of volcanic magma. As magma ascends through a volcano, it depressurizes and carbon dioxide bubbles form.

When the magma reaches the surface, it hits the freezing cold sea water and solidifies into rock. And when it does that, it traps the bubbles inside of it. So it would be like flash-freezing this glass. And the photograph on the right is one of these underwater volcanic rocks with bubbles trapped inside of it that's seen under a microscope. And so now we can take this rock into the lab and measure the composition of the gases that are trapped inside of the bubbles to figure out what the volcano is emitting as a whole.

And here's one example of something we found. I mentioned before that volcanoes emit carbon dioxide to the atmosphere. But how much? Measurements of volcanoes on land, all those little red triangles that Tobias goes to, it turns out they only emit about half of all volcanic carbon dioxide. These underwater volcanoes emit about the same amount of carbon dioxide as the above water volcanoes. And the data that goes into this yellow pie slice, it involves measuring and compiling hundreds and hundreds of individual samples. And a lot of the really important samples for this work are actually housed right here in the Smithsonian's National Rock and Ore Collections.

Now while it's important to know how much carbon dioxide volcanoes are emitting naturally, it's also important to keep in mind that volcanoes emit just a tiny fraction of what we as humans are putting into the atmosphere ourselves, the anthropogenic emissions in this gray pie. Okay so I've talked about exhaling, that's volatiles coming out of the Earth's into interior. What about inhaling? Does the Earth do that too?

Well, the answer is yes. Using those very same measurements of bubbles in those underwater volcanic rocks, we can look carefully at the composition of those bubbles. When we do that, we see that it turns out they actually look a lot like seawater. And it's not the seawater that they're erupting into, it's actually seawater that was long ago pulled down into the Earth's interior, maybe a billion years ago, and it's now found its way back up into a volcano near its surface.

So what I'm showing here is a movie of a numerical model. This is like a computer simulation of material moving around in the Earth's interior; basically the Earth's mantle. The hole in the center of this is the core and the outside edge is the surface. And the rock moves around in the mantle basically like a lava lamp. It gets heated at the bottom by the core, and it rises up, and then cools down at the surface, and then sinks back down.

And in this simulation, the purple streaks that you see are actually rocks, basically tectonic plates, that are dragging sea water with them back down into the earth's interior. And these rocks get stretched, and folded, and mixed, and sometimes they come back up to the surface and erupt in another volcano.
So we use these kinds of simulations, these models, to explain how the volatiles that are coming out of volcanoes today are actually ones that have been previously subducted long ago in Earth history and have gone through this cycle through the Earth's deep interior and back out.

As a final example, one of the things that I'm studying right now is not just how Earth is breathing now, but also in the deep past. So what did the Earth look like very early on in its history? Was it like a dry hellish landscape? Was it kind of similar to what we have today or was it something totally different like a Water World?

Today, more water is actually going into the Earth's interior than is coming out. So the oceans are actually shrinking is what that means. It's kind of like a bathtub that's draining just a little bit faster than it's filling up. But was it always this way?

To look at the deep, deep past, we can look in detail at a particular volatile element, xenon, it's one of the noble gases. And xenon, it's not too useful to most people, but it's great for geologists like me because it has a really special isotopic clock built into it. It keeps time by radioactive decay. So xenon can actually remember events and conditions on the Earth billions of years ago.

What I'm studying right now is how this xenon clock relates specifically to water and how we can leverage the xenon clock to understand the history of water at the Earth's surface. And what I think right now is that ... So the bathtub ocean is draining a little bit faster right now than it's filling up, but maybe one or two billion years ago, and the Earth is four and a half billion years old, so a billion or two billion years ago, the opposite was true. The ocean was actually filling up faster than it was draining.

So billions of years ago, the Earth might not have looked like it does now. It might have looked much more like an ocean world. And all of this is the result of earth breathing not just today, but all throughout Earth history. So thanks everyone for your attention and I look forward to any questions you might have.

Amanda Sciandra:
Thank you, Jonathan. You have the best analogies. Thank you so much. And you've certainly given us a lot to think about. I'm sure there'll be a lot of great questions from the audience. Thank you to those who have already submitted your questions. Keep them coming, and we'll get to as many as we can after our third speaker.

So our next guest is Clare Fieseler. Hey Clare. Clare is a marine ecologist. While her previous research focused on monitoring climate stressed coral reef ecosystems, starting next month she'll begin a fellowship at Natural History where her research will synthesize new and existing data to design monitoring strategies for marine mammal populations in the Arabian Gulf, a natural laboratory for understanding past and future climate extremes.

As part of her fellowship, Clare will also study whether open access and data diplomacy effect conservation dialogue between countries and the Gulf region. In addition to her work as a marine ecologist, Clare is also an accomplished journalist, documentary film writer, filmmaker, science writer, and former AAAS Mass Media Fellow. Her first book, "No Boundaries: Advice from 25 Women Explorers, Scientists, and Adventurers," will be published by National Geographic Kids Books in February 2022. Congratulations, very exciting. So Clare, take it away.

Clare Fieseler:
Thank you so much, Amanda. So I want to take you underwater. This is Belize, home to the world's second largest barrier reef. And this is a pillar coral that you're looking at. In my opinion, it's one of the most adjusted corals in the world. It can live up to a hundred years. And while this one that I took a picture of, it's about three feet high in height, these can grow to about 10 feet tall which is a height of a standard basketball hoop.

And most people know that coral reefs are one of the most diverse ecosystems in the world. About half a billion people around the world rely on them for food and income. In the Caribbean, they are one of the main drivers for tourism. So it made sense in the 1980s for a lot of Caribbean countries to start protecting these. And the most common way they did that was through something called a marine protected area. And these are essentially national parks in the ocean. And like a lot of people, I'm going to use the terms protected areas and marine parks often interchangeably throughout this talk. It's because people from around the world use them in different ways. They mean the same thing.

But these marine parks have been in the news quite a lot recently. This graph shows a dramatic rise of these parks in the Caribbean specifically and this is definitely newsworthy. But this picture alone doesn't capture the full story. And if we kind of pull out to the global scale, these dark areas are existing marine protected areas with the stripe pattern areas representing new ones that are going to be formed and implemented in the coming years.

The takeaway from these two slides is of global rise in protected areas but again, it's not the full story. And the story I want to tell you instead starts here. This is Carrie Bow Cay, it's a patch of sand about the size of the football field with 88 palm trees and just a couple of wooden cabins. And it's the home of the Carrie Bow Cay Field Station and for the past 50 years or so, the only people that have visited this island are Smithsonian researchers and their affiliates. It's considered one of the longest studied and best studied patches of reef in the Caribbean.

And in 2011, a protected area started protecting the reefs around this little island and around our little field station. And the Smithsonian started to monitor, "Hey, what's the effect of this reserve going in on these corals?" Now I just want to quickly say that what my friends think I do when I go down to this island, I've been down over a dozen times, they think I eat a lot of pineapple and sit on the beach and drink rum.

Now to be fair, I do love the beach. I grew up on the Jersey shore and I dove on a Caribbean coral reef for the very first time when I was 16 years old. And just in my lifetime, I'm 36 now, I've seen dramatic changes on these reefs and once you see that, you really can't [inaudible 00:19:09].

This is what I think I do when I'm down at Carrie Bow, swimming around, diving, collecting data, being a real marine scientist. But in reality, this is what I actually do. Spend a lot of time processing samples in the lab, both on the island and then back at the Smithsonian or just crunching numbers of the data that we collected.

Now I've been part of two really important monitoring efforts led by the Smithsonian about the reefs right around this island. And one is this 20-year data set of how the temperature of the sea water on these reefs is rapidly changing. And it meant that every six months I'd be part of a team that would dive down and swap out these yellow thermometers, essentially, that you see in this picture and we just published that data set last year.

I've also been part of another program, which I mentioned, to monitor the effects of the new marine park that went in. And it's not surprising that our data actually hasn't been published over the past 10 years, because often scientists have reasons for why they want to wait. We want to see long-term trends and kind of get a sense of what's really happening before we jump to assumptions.

But it really got me thinking. We've published this data set, but if Carrie Bow is one of the best studied, the longest studied reefs in the Caribbean and our monitoring data for this park isn't out there, our reefs and other marine parks in the Caribbean, are they really being fully illuminated about their health so that decision makers can manage them in the best way possible?

And I'm sure everyone will be familiar with this picture. And the reason why this is important because on the right is this reef stressed by ocean heat waves that are driven by climate change. These pictures represent the most critical threat to a reef today, which is climate change.

These pictures weren't on people's minds when most of these marine parks were created. Marine protected areas in the Caribbean were mostly created for these guys. This is a nurse shark that's gonna visit me while I'm doing an underwater survey at Carrie Bow. These parks were set up to stop overfishing and, to some extent, pollution. And while I mention this, a basic fact about protected areas, it's a good time to maybe give some more basic facts about what they are and how they work.

So what's a marine protected area, how does it work? Well, first it's designated and then once it's implemented, the threat it was set up to stop, mostly fishing, goes away. With time through active management, we hope that the resource rebounds. Active management entails patrol boats making sure that rules are being followed, collecting data on the reef, engaging local communities.

But something interesting happened in the early 2000s is that a lot of scientists from around the world realized that a lot of these parks were essentially paper parks in that they existed on paper, they weren't being implemented or even enforced. And so this was a real problem for conservation and trying to get conservation outcomes through these corals.

Now the good news is that there's some initial evidence that this paper parks problem is getting better in the past 20 years that it was first detected. But the bad news is that there's new threats that are worsening every day, which is climate change.

This coral that I mentioned earlier is particularly sensitive to bleaching from these ocean heat waves and also disease that we believe gets worse when things get hot. And even in 2014, this particular coral was listed as threatened on the endangered species list. And so it's really critical that we keep a pulse on how corals are responding to climate change, especially in these special places like marine parks.

So I kind of set my view on another part of the Caribbean to do this research, which is the insular Caribbean, as seen in this map, it represents more of the highest densities of marine protected areas in the world, 428. And I really wanted to see, okay if we're making a little bit of progress on implementing them and enforcing them, then we also should be measuring how they're doing, their trajectories over time, their health, saving that data and sharing it.

But I was very suspicious that we weren't making progress in that arena and that, essentially, by blocking the collection and sharing of data, that decision makers were essentially in the dark, how to respond to climate changes, things were getting worse.

And so I started working with some global partners actually, that you see listed here. And I mentioned earlier that there's some evidence that this paper parks problem's getting better. And we know that in the Caribbean at least because one of these partners here has been working directly with managers of these parks, about 36 of them, and surveying them over time. And essentially these managers of these marine parks said, "Hey, we're less concerned about enforcement and we're more concerned about having data. And not just any data, but the data that we need to make the most urgent questions related to our parks, which is mostly climate change."

So it really got me thinking to what extent are we solving the problem of paper parks but creating this new problem of parks in the dark, in which we don't have enough information critically? And what this means for the health of marine parks in the Caribbean is that we want to be collecting data in all parks, but the right sort of data, climate relevant data.

And there's a lot of data that was collected for a long time that was related to the state of a coral reef. But with climate concerns, we really want to know about the rates of change of a coral reef. Because we know that they're going to change with climate change and we want to know what areas would be more resilient to change than the other? We call that climate resilience data.

And so here are some of my results. How many marine parks have climate resilience data, this gold standard of climate-relevant coral data in the insular Caribbean? Well these four dots represent the total amount of reefs in the Caribbean that have this climate-relevant data and this orange dot represents all of these. So everything you see in orange are places in the Caribbean we're not collecting climate-relevant data right now. And this was a pretty big shock to us.

Now the next thing that we did here is trying to see, okay beyond the publicly available data, can we pull out the dusty filing drawers of maybe data that's been sitting on shelves or sitting on people's hard drives to understand is there other data out there we don't know about? And a lot of this work has been done during the pandemic when none of us were traveling and we're all sitting at home. This is a picture of my daughter sitting in front of a filing cabinet at the Smithsonian and so there was the real filing cabinets I asked people to look in and the proverbial ones of their hard drives.

And the good news is that these gray dots represent parks where we have some monitoring data. It might not be as climate-relevant as we need to understand rates of change, but what I'm working to do right now, not just with the data we've been collecting for Carrie Bow but other places, is how can we retrofit data to become more climate-relevant? And that's kind of the work that I've been in doing right now just to understand which corals will survive and which won't.

What strikes me about all of this is that marine parks have always been an ambitious idea. And when we started out, there were these problems. First they're on paper but were really not enforced and they're not having the effect that we want. But then we kind of pat ourselves on the back and said, "We've taken care of that problem." But we should not forget the other problems that essentially arise from climate change becoming new to the scene and being an ever-present threat.

And what gives me hope, though, in kind of illuminating where we have data and where we do have data retrofitting it for climate change, is that this really is the work of what the Smithsonian does is taking kind of dusty data and repurposing it to confront the problems of today that we know about and the ones that are coming down the pipeline. So thank you very much, and I look forward to your questions.

Naimah Muhammad:
Thank you, Clare. Thank you so much for literally, I guess, shining a light on parks in the dark. So thank you. We have a lot of really great questions coming in. So audience, thank you, but keep them coming. Let us know who your question is for and I will keep things moving.

Our last speaker, Gary Krupnick, he is a research scientist at the Smithsonian's National Museum of Natural History where he heads up the plant conservation unit. He advises organizations on the International Union for Conservation of Nature plant listings, and he represents the Smithsonian on committees for plant conservation and pollination.

Dr. Krupnick studies plant conservation biology, plant reproduction, the use of herbarium specimens to determine rarity and the endangerment of plant species, and plant pollinator interactions. With the American Society of Botanical Artists, he co-curated the traveling exhibition, "Losing Paradise Endangered Plants Here and Around the World." This exhibition was a convergence of art, science, conservation, and education.

Dr. Krupnick serves on the steering committee of the North American Orchid Conservation Center and is the Vice Chair of the Steering Committee of the North American Pollinator Protection Campaign. He's the co-editor of the book, "Plant Conservation: A Natural History Approach," and he serves as the co-editor of the Plant Press. And I believe we put a link to the book in our Q&A here, so I hope you'll check it out afterwards. But for now, please let's welcome Gary. And you can take it away. And I ... Just unmute yourself when you get a chance. But the screen share is great.

Gary Krupnick:
Sorry, yeah.

Naimah Muhammad:
Here we go.

Gary Krupnick:
Thank you so much, Naimah. I'm so happy to be here. Yeah, let me just adjust things on my computer real quick. All right, so what I would like to do is ask you all a quick thought exercise. When you hear the words endangered species ... oh yes?

Naimah Muhammad:
Hey Gary. Yes, let's do a swap. The display settings, we are in presenter mode on our end.

Gary Krupnick:
Oh.

Naimah Muhammad:
No worries.

Gary Krupnick:
And let me get going here again, sorry.

Naimah Muhammad:
While Gary does that, I'll make a plug for Pollinator Week coming up in June, which Gary does a lot of work on as well and maybe we'll learn more about doing the Q&A. But it's a very special time.

Gary Krupnick:
Okay, let's try this one more time. Does this work?

Naimah Muhammad:
So far, so good.

Gary Krupnick:
That looking good?

Naimah Muhammad:
Yeah, I-

Gary Krupnick:
Okay.

Naimah Muhammad:
I think we're good.

Gary Krupnick:
Good. All right, thank you for that. So again, sorry about that. I'd like to begin with a quick thought exercise. When you hear the words endangered species, what's the first species that comes to your mind? Now real quick, think. What comes to your mind when you hear endangered species? Now some of you thought maybe of a mammal like a panda or the tiger. Maybe was a bird like the California condor. Perhaps you thought of a reptile or amphibian like a sea turtle or the golden frog, or maybe a fish like the seahorse.

I'm feeling that many of you cannot think of a plant, like this eastern prairie fringed orchid. In fact, the tendency to ignore plants and be biased towards animals is actually a measured phenomenon. Now it's important, however, to identify all endangered species because each and every species on our planet is a part of a complex puzzle of life on earth. And if one piece of that puzzle goes extinct, it reduces the stability of all surrounding pieces of that puzzle.
So now let's look at how much effort scientists have put into identifying which species are actually endangered. Now this here is the IUCN Red List of Threatened Species. It's the go-to source globally for the conservation of species.

In the latest 2021 edition, 91% of mammals have been assessed for their conservation status. All birds have been assessed and we're doing pretty well in reptiles, and amphibians, and fishes. But for plants, only 13% have been assessed for their conservation status. And more progress has been made for plants however than for insects or for fungi at 1% and at 0.03%. There's many reasons behind this, it reflects how many species are in each group.
There are close to 73,000 vertebrates but there are six times as many plant species. It might also reflect that we have a lot more information about animals than plants. Zoologists have a really good idea of the distribution and population sizes of animals, but we know a lot less about plant population sizes and distributions. Conservation biologists research ways to prevent extinction, but we can't save the species if we don't know if it's extinct or if it's endangered. So how can we speed up that process of evaluating which plant species are actually endangered?

We can turn to natural history museums. At Smithsonian's National Museum of Natural History, we have about five million plant specimens housed at the U.S. National Herbarium. Across the world, there are over 3,400 herbaria approximately 400 million plant specimens. 400 million plant specimens, that's a huge treasure trove of data. Most of those specimens, however, are not readily available online. But at the Natural History Museum, we are making great progress in making those specimens available for study.

In the herbarium, we are currently digitizing our entire collection of pressed plants. Using conveyor belt technology, between 3,000 and 4,000 specimens per day are imaged and digitized. At the end of last year, we reached the 3-million-record mark. These digitized specimens make the data contained within them readily available for researchers to analyze.

So what is a plant specimen? Well they are dried and pressed plants that are stored for scientific purposes such as documenting, identifying, and classifying the world's flora. A key feature for the conservation biologist is in that specimen label. That label in the lower right hand corner of the specimen, it tells us the who, what, where, and when of the specimen.

So in this case, this is Santalum fernandezianum and it was collected on the Juan Fernandez Islands in Chile by C. Scottsberg on the 25th of August 1908. This label has another piece of critical data. Scottsberg wrote in his own handwriting that, "This branch was from the last tree." You see, Chile sandalwood was overharvested over a century ago for its aromatic wood and it went extinct and, thus, no longer exists today. So these specimens that we have an extinct species, they're the last piece of evidence that they ever existed before on our planet.

So we are now using specimens beyond their original intent. One way is in conservation research. To assess the conservation status of plants, I've developed a model in which I plug in several pieces of information from these plant specimens. I measure abundance, that is how many specimens have been collected. I measure space, where does it grow and how wide is its distribution? And I measure time, how current or how far back are the collections? All three pieces of that data are used together in a model to help determine the conservation status of the species.

With adequate data, species can then be assessed and placed into one of seven different categories of the IUCN Red List of Threatened Species. The not threatened categories are at "Least Concern" and "Near Threatened." The threatened species are "Vulnerable," "Endangered," and "Critically Endangered." And that species may also be declared either extinct in the wild or extinct.

One group that I'm currently assessing is this Heliconiaceae. It's a plant family of hummingbird-pollinated tropical plants. Using geo-reference data, collection date, and knowledge of protected habitats, I'm producing the very first conservationist assessments for all 180 species in Central and South America from this beautiful and economically important plant family. So now I'm going to share two different examples from my study.

First here is Heliconia bihai, the species found in South America and the Caribbean islands. It has a large geographic range. Each dot on that map represents one of 177 specimens of the species that were collected between 1884 and the present. With a wide distribution, a high number of populations, and populations abundant and size, I've assessed this species as least concerned.

Now compared that to this species, Heliconia aurea. Heliconia aurea is different from the last species because it has larger and more curved flowers and bracts. It is only found in Venezuela and Colombia with a very narrow geographic range. Only seven specimens have been collected from these sites recorded in 1953 and between 1990 and 1993.

And while the Venezuelan populations are protected, the Colombian population grows in an unprotected habitat. So with the small distribution size, only three populations and one population unprotected, I've assessed this species as "Vulnerable." With this knowledge at hand, management practices can then be put into place to prevent this species from going extinct.

Museum specimens can be useful beyond species conservation assessments. They can also indicate how the environment is changing. So now I want to bring it closer to home. Especially if you are watching in the D.C. region, this here is a specimen of lichen. Lichens are too small and delicate to mount plants on a herbarium sheet. So often lichens are held within the packets glued to the sheet.

This specimen here was collected from Plummers Island. Many of you in the D.C. region drive over Plummers Island every day as it sits in the Potomac River directly under the D.C. Beltway Bridge. In the late 1970s, scientists from the Smithsonian and George Mason University collected lichen specimens from this site, Plummers Island, and from Bear Island. Bear Island is located about seven kilometers upstream from the bridge.

They were able to measure the lead content of the lichen specimens and found that specimens from Plummers Island had almost seven times as much lead as the specimens from Bear Island. One other interesting fact, that bridge, it was built in 1965. They found that specimens under the bridge had higher levels of lead concentration than specimens collected from the exact same site but before the bridge was built. Thus, these lichens are showing atmospheric pollution stress from car exhaust. So their research actually helped lead the case to ban the sale of leaded gasoline.

Specimens can also help measure the effects of threats on species. We can measure changes in distribution, that is our plants moving to more favorable areas. Changes in morphology, is their appearance changing or leaves or flowers getting larger or smaller? Physiology, what is happening inside the plant? And changes in phenology, are plants flowering earlier in the spring?

For instance, how is global climate change affecting the physiology of plants? Working with a scientist from the U.S. Department of Agriculture, we examined the protein content of pollen from historic specimens of Canadian goldenrod dating from 1842 to the present. Goldenrod was chosen as it is a critical food source of nutrition for honeybees and other pollinating insects during the fall months.

This graph here shows the average protein concentration from anthers and pollen of 350 goldenrod specimens from the herbarium. Each point on that graph is the average of between six and 40 samples per year from different regions of North America. And what we found is that as atmospheric carbon dioxide levels increase, the protein content of the pollen grains decrease. Thus, an increase in carbon dioxide over the last several decades have made a key food source for bees less nutritious than in the past.

So every bite of pollen that a bee takes today from goldenrod is less nutritious than what their grandparents ate years ago. And so you have to ask yourself a question, "Does every single bite of an apple that you take today, is it less nutritious than the bite of that apple that your great grandparent took years ago?"

So I've just showed how we're using specimens from the 1800, the 1900s, and from the past 20 years in shaping our understanding of plant conservation. It's incredible that we're using specimen in ways the original collectors could never have imagined. And it just shows the importance that museum collections have in shaping our future. Thank you so much and I look forward to your questions.

Amanda Sciandra:
Thank you, Gary. All right. So thank you everyone who has entered their questions already, we've got a ton. And thank you to Jonathan and Clare as well. And everyone can join us back on here. All right, the team's all here. Excellent. So let's just dive right in here. The first question is for Gary actually. Are you ready, Gary? I know you just-

Gary Krupnick:
I'm ready.

Amanda Sciandra:
Okay, good. The question is from Liz, "How is the museum managing and using this enormous new data stream when you're digitizing the collections?"

Gary Krupnick:
Great question. Hey, Liz. So we have, as I said, digitized over, I don't know, about three to four million specimens from the herbarium. That data is just sitting there waiting to be used. And so we could ask a lot of different questions, like I said, asking about changes in phenology or distribution.

It just takes scientists and researchers to access that information. And a lot of that data is available in our databases on the web. So I encourage you to that, if you're a scientist and you want to explore questions, that data, you could get access to that right on at the Natural History's website. And I would love to take on some postdocs and undergraduate students and ask these questions with the data that we have.

Naimah Muhammad:
Thanks Gary. Okay, so Clare let's jump to you with a question from Ronan. And the question is, "What is the name of the coral in the first photo of your slideshow?" Oh, there we go.

Clare Fieseler:
That's called a pillar coral. And as I mentioned, it is one of 20 corals that was listed in 2014 as threatened by under the U.S. Endangered Species Act. And so it's particularly sensitive to bleaching by heat and to disease as well. And unfortunately, we've had some local extinction of the coral in places, in parts of Florida, and also in The Bahamas. So a highly majestic but a very increasingly threatened species as well.

Amanda Sciandra:
Thanks, I love that image. Okay, next question here is actually a twofer and it's for Jonathan. Jonathan this is from two different askers, but they're kind of getting at the same thing or related to the same topic. So the question from Robin and Randy is, "Why is sea level rising if the ocean is draining?" And then Laura asked, "Has the rate of draining been consistent with the loss of water through subduction?" So both related to draining here, maybe you could tackle them at the same time.

Jonathan Tucker:
Thanks. Yeah, those are super great questions. I'll answer the second one first. The ocean draining that I was talking about actually is the return of water into the Earth's mantle via subduction. Subduction is the term for it. I just was trying to be a little bit jargon-free.
The first question is a little bit ... it's a great question. Why? If I'm saying that sea level's dropping, why do we think it's rising? Well the answer is, it's actually both and it depends on what time scale you're looking at.

So over human time scales, the scales of years to kind of centuries, even millions of years, sea levels are rising due to a combination of various effects that operate on short sort of human-relevant time scales. The time scales that I'm talking about are hundreds of millions to billions of years, which are much longer time sort of geologic time scales, and over that time period, the sea levels would be falling. So overall, they're kind of falling, but there are wiggles up and down on shorter time scales and we're in one of those little wiggles right now.

Naimah Muhammad:
And just Jonathan as an aside, we had so many comments about just how great your analogies are, and so I think you've provided a lot of nuggets of information for people to really comprehend. So just wanted to make a shout out there.
Gary, a question for you from LN. And the question is, "There's a lot of discussion about bringing extinct animals back. But would it be possible, if not easier, to bring extinct plants back like the Chilean sandalwood?

Gary Krupnick:
That's a great question and it's more of an ethical question. Yes, we have amazing access to DNA and we could graft species onto each other with plants. Ethically though, does it make sense to bring a species back if its habitat is now gone? Or does it make sense to bring a species back if its pollinator is no longer with us and it can't get pollinated? And so I'm not going to actually give an answer saying, "Yes we should." Or, "No, we shouldn't." I'm just saying that it should be up for debate and a lot of conversation, heavy conversations to bring back something that is no longer here.

Amanda Sciandra:
Speaking of how species change over time, Clare there's a question from Rita asking, "Are there other photos showing changes seen with the one coral, the threatened one that you mentioned, so as a photographer even can you speak to this?"

Clare Fieseler:
As a photographer, I will say one of the hardest things about communicating the threats of climate change to the ocean is that we are just not aquatic species. We are land animals ourselves and it's hard sometimes for people to recognize a coral that is affected by a climate change and not, or even a dead coral and a live coral and that's why bleaching is such a very stark image.

I don't have pictures particularly of that coral or that species being impacted that I've taken, but I really do recommend ... There's some really great documentary filmmakers out there that are really trying to solve this problem of how do you visualize climate change when it is so invisible in some ways?
And I recommend a movie called "Chasing Coral." It's available on Netflix and it provides amazing visuals of the bleaching process. Which I should mention doesn't mean that a coral is dead, it just means that it's highly stressed, but if it's bleached for long enough it can die, and so I want to make that clear too. But I recommend that film and you touched on a great problem that we're trying to address is how to communicate these changes which can seem so invisible at times.

Naimah Muhammad:
We actually showed that film a few years ago when it came out as part of the Environmental Film Festival, a really, really spectacular film, so that's a great recommendation. Thank you for the reminder also, Clare, about that film.

Okay. So moving along, we have a question for Jon-, let's see, yes a question for Jonathan from Natalie. And the question is, "If CO2 gas becomes trapped in the lava samples due to the freezing from the water temperature, how does it then become released to the atmosphere? Was the water filling Earth's surface as a result of impacts?"

Jonathan Tucker:
Okay Natalie, those are two great questions. I think that those are sort of two separate questions. The second question is kind of like where did Earth's water ultimately originally come from? Is it coming from impacts of extra terrestrial objects? The short answer to that is we don't actually know.

They're kind of two hypotheses. Either the Earth formed without any water and it was added later by impacting material like asteroids, for example. And another hypothesis is that Earth always had its water and it basically formed as wet as it is today. And there are good arguments for both of those cases and it's not something that's solved and something that many people have been working on for decades.

For the first question, how ... Yeah, if the carbon dioxide is trapped in the bubbles, how does it actually get out to the atmosphere? Yeah, so when I showed that analogy of the champagne glass, a lot of those bubbles have already left the "magma" before the time that it freezes. So a lot of it has de-gassed before the magma freezes.

Exactly how much has left and how much remains there. That's a tricky thing to figure out and that's what some of my work has gone to actually trying to solve. But that's just at the moment that it freezes. And then over some geologic time, that rock sample, that lava that's been erupted that has those bubbles frozen into it, it's going to degrade because it's in contact with the ocean water and it's going to react. The ocean water's going to react with the rock and kind of degrade it. And eventually any bubbles that are still trapped in that are going to get released into the atmosphere.

So when we get these samples and want to make the measurements on them, we actually have to get samples that are relatively fresh, that have been erupted relatively recently in geologic time, so that they still have those trapped bubbles inside of them and they haven't degraded and released them into the atmosphere. And that can definitely be a challenge when we're trying to grab something that's three kilometers, five kilometers, like 10 miles under water without knowing exactly where it is.

Amanda Sciandra:
Perfect, thank you. I'll never think of a champagne glass the same. Thank you. Okay, this next one is for Gary. It's from Mrs. Dean. The question is, "I actually found out how plant life can affect other species. Recently I found out monarch butterflies made the endangered list. What I did not know was the lack of milkweed contributed to that, plant species. Are humans a main reason why some plants are endangered or is it attributed to climate? And I know Naïmah mentioned pollinator week, so maybe this is also a good time for you to tell us more about that." And I'm happy to repeat any of that if you need me to.

Gary Krupnick:
All right, yeah. Thank you so much, that's a great question. So yes, many of the plants that are endangered today are due to many different factors. Habitat loss being the main factor. If you get rid of a habitat, there's no place for that plant to grow anymore.

Climate change is having a big impact, herbicides are having a big impact, and other pollution factors. Invasive species, plants that don't belong there but that grow elsewhere but have been transported by humans into a new location, they might out-compete other plants. And so there's a lot of different factors that go into plants being endangered.

With pollinators, there's also a bigger complex question there, especially if you have very dependent process in which one plant is highly dependent upon another pollinator and if that pollinator is highly dependent upon a plant. And so in the case of the monarch butterfly, monarch caterpillars only eat milkweed plants, that's the only plant on this planet that monarch caterpillars eat.

And a lot of farmers and homeowners find milkweeds to be a problem because they're quite weedy and so they might take over agricultural land. So a lot of, for the past couple hundred years, we've been trying to clear away a lot of that milkweed for farming and because of that, there's a lot less nutrition, a lot less food for these monarch caterpillars.

And so now there's this big effort, especially during Pollinator Week, in which we are encouraging homeowners to start planting native plants, plants that are native to your region. Pollinators need those native plants because that is the food source that they are adapted to, whether it's nectar or pollen from those species and it helps the native plant populations get bigger as well.

And so we have a big outreach and a big push to start encouraging homeowners to garden for native plants, use native plant species for pollinator gardens. And believe me, I could talk for a full hour about that topic as well and maybe I'll save that for another science café in the future.

Naimah Muhammad:
Well we also have the Earth Month events coming up later this month and Gary will be a part of that, so tune in for our future programs. But as we are wrapping up the end, there's great question that came in from the audience which is directed to all.

Not only do we have young professionals, other science folks and educators in the audience, but we also have teachers, we have kids, we have families, and parents. So a question to kind of end on some inspiration here is to all our wonderful speakers, how did you get interested in your career? Clare, I'm going to start that with you and then maybe Jonathan and Gary, you can follow.

Clare Fieseler:
I was actually thinking about this last night because there's a couple of philosophers which are thinking about why do we value nature? And there's been two different arguments. One is that nature has intrinsic value. We should value a tree because it's a tree and there's nothing quite else like a tree in the world. Or there's economic value. We value a tree because it provides shade, it provides nectar for pollinators, it reduces the urban heat island effect.

But a lot of philosophers are thinking in these days about relational value, like that it helps us build relationships. And I feel like I've always had a relationship with the ocean growing up near it. And so I had a personal relationship with the ocean and I just kind of let that lead me. And I started off in documentary filmmaking, and in journalism, and then I went back into science, and now I kind of merged the two.

And I report on the things that are not related to the ocean but all my research is related to climate effects on the ocean and biodiversity. And I'll just go back and saying that I think it really comes down to relationships. And you have a personal relationship with something, whether it's a sense of justice you want to be a lawyer, or a relationship with kids and you want to be an educator. For me was just a relationship with the ocean, it kind of took me to where I am. So it's a long way of giving you an answer, but I hope it makes sense.

Jonathan Tucker:
I'll jump in. To sort of go on the theme of earth scientists and natural scientists tend to have an origin story, it's possible I might have made my parents drive me out hours into the desert to go hunt around for rocks when I was a little kid. That definitely happened. And so I've always kind of had earth science with me.

But I'll actually tell you something that's maybe a little bit surprising. A lot of earth science today actually is not climbing around in the desert, climbing mountains, collecting rocks. There is some of that, but a lot of our work is actually in laboratories and in front of computers. There's a lot of statistics and numbers and analysis, so it's actually much more of a quantitative science.

So if you have an interest in the Earth but your skills are really in programming, or machine learning, or things like that, earth science will definitely have you. So there are a lot of ... Earth science is great, it's such a multidisciplinary field that there are a lot of ways to get into it.

Clare Fieseler:
And just as a quick plug. If you aren't quantitative, the sciences will still have you too. The field of ecology, there's a lot of people that use statistics, but you don't need ... You can always partner with someone who is really good at statistics. Maybe you're really good at coming up with good questions and that's your contribution, so you don't necessarily have to be quantitative person either. I don't consider myself to be one, especially, I just kind of get by in those things.

So I think that there's a spot for everyone for all skills when it comes to science. And few people realize that there's all different types of fields with their own cultures and specializations, so.

Gary Krupnick:
Exactly, yes.

Naimah Muhammad:
Great illustration.

Gary Krupnick:
Okay. Talk about my own origin story. I didn't have any specific a-ha moment when I was a little kid. My parents actually deprived me from going out into the woods with them and going camping. We just didn't, I lived a very urban life.

But it wasn't until college that I knew I was really good at STEM sciences, I was really good at math. And I bounced from major to major. It's math, and it's chemistry, and it's physics. And then I ... For all you with teachers out there, it's being a great teacher for student. And I had an amazing professor in college who taught ecology and evolutionary biology and he just blew my mind. I mean, he was just ... It was completely fascinating to me and I didn't even realize that was something for me until I actually took that class.

And it was at the same time that they were just discovering a hole in the ozone and they were discovering that a lot of the rainforests were being cut down and so that really drove my conservation side, realizing, "Wow, this Earth is amazing." There's so many bizarre, crazy things out there, neat plant-animal interactions, and amazing questions to be asked, but we're losing it quickly due to deforestation. And so that sort of drive me towards the conservation side of being an ecologist and that's how I took off. It wasn't until that one inspiring professor that really got me going into that field.

Naimah Muhammad:
And that's a perfect way to end because I hope the three of you, I'm sure have inspired some of the folks on the call, but especially inspired some of the folks on the call who were maybe interested in exploring some of these fields, so I hope that's a great takeaway for everyone. And with that, please join me and Amanda in thanking our three speakers. What a great, great event. So thank you all. Round of applause.

Amanda Sciandra:
And we also want to give special thanks to those who made the program possible. First, big thanks to Busboys and Poets, our amazing restaurant collaborator. If you didn't place an order or try one of the themed drinks this time, definitely add it to your menu for next time.

Thank you to our behind the scenes team who helped sort through your questions, our donors, volunteers, viewers like you, and finally to all our partners who help us reach, educate, and empower millions of people around the world today and every day. Thank you.

Naimah Muhammad:
Thank you. And of course, we hope you'll join us for the final program in this year's series which is coming up in May and our many other programs to come. Gary's in a few of them coming up in these next weeks, so hope to see you again for that.

We have put a link in the Q&A where you can find information about our upcoming programs and how to sign up for the museum's weekly e-newsletter, which is the best way to stay informed on upcoming programs, interesting news and findings, and to learn more about the museum's research and exhibitions.

Amanda Sciandra:
After the webinar ends, you'll see a survey pop up asking you for your feedback about the program. Please take a moment to respond. We're very curious to know what topics you might be interested in seeing for future programs, and we absolutely appreciate your input.

Naimah Muhammad:
Awesome. So again, thank you to our participants. Thank you audience, and thanks we will-

Amanda Sciandra:
Thanks for having.

Naimah Muhammad:
... see you soon. Thank you all.

Amanda Sciandra:
Thank you.

Naimah Muhammad:
Thanks everyone. Bye.