IRA FLATOW: We’re continuing our conversation about the Sonoran desert ecosystem. We just talked about the health of the saguaro, the Desert’s most iconic cactus. But you know what? The Sonoran Desert is so much more than just cacti.

The 100,000-square-mile desert reaches across the US-Mexico border. The northernmost portions, in Southern California and Arizona, make up just 1/3 third of the Desert. The majority of the Sonoran is within the Baja California Peninsula and the Mexican state of Sonora.

The region also includes the Gulf of California, which is teeming with life. In fact, Jacques Cousteau once called it “the world’s aquarium.” What a great vision that is.

Joining me now to talk more about the rich biodiversity of the Sonoran Desert and the importance of scientific collaboration across the border are my guests Ben Wilder, director and co-founder of Next Generation Sonoran Desert Researchers, based in Tucson, and Michelle Maria Early Capistrán, a conservation fellow at Stanford University and board member of the Next Generation of Sonoran Desert Researchers. She’s based in Monterey, California.

Welcome, both of you, to Science Friday.

BEN WILDER: Thank you, Ira. Honored to be here.

MICHELLE MARIA EARLY CAPISTRÁN: Yeah, thanks. Great to be here.

IRA FLATOW: Nice to have you. Ben, let me begin with you. I think that most people, the Sonoran Desert starts at maybe Phoenix and ends in the Grand Canyon, right? Do you find that to be true? Do you have that feeling?

BEN WILDER: So I’m born and raised here in the Sonoran Desert. And when I was a little one, yeah, that was true for me. I grew up with the saguaros in my backyard. And the desert was this area just around my backyard.

But I’ll never forget when I first learned that, as you said earlier, the majority of the Sonoran Desert is to the south. It’s the entire Baja California Peninsula, almost the entire state of Sonora. We have our own ocean. It blew my mind. And I’ve honestly spent my life since then exploring that.

IRA FLATOW: I never knew that either. It is a mind blower. And Dr. Capistrán, do Mexicans feel the same way– they really don’t know how big the Desert is?

MICHELLE MARIA EARLY CAPISTRÁN: Well, I would chime in that, for most people in the United States, it starts at Tucson and ends at the Grand Canyon. I think for most people in Mexico, it starts where the [INAUDIBLE] starts. So just north of where the greenery ends. And at least from the South, from Mexico City, I think it’s generally just seen as a vast empty spot. Northerners would think of that very differently, of course.

IRA FLATOW: Well, Ben, your organization, Next Generation of Sonoran Desert Researchers, is out to disabuse everybody of that notion. Because you’re connecting scientists from the US and Mexico, as well as local communities. What motivated you to start the organization? What was missing in the way that the Desert has been studied in the past?

BEN WILDER: Well, as you said earlier, this is such a vast region. And the inherent nature– the biological and cultural diversity of this region– does not adhere to political boundaries, which are quite often arbitrary.

And I was coming of age as a scientist in this region, and with a couple collaborators as well at the beginning of our careers, and we were looking around and really seeing, where is this larger community? Does a larger community exist that shares a passion for this region and is studying this? And we didn’t know the answer to that.

It’s so important because this region doesn’t adhere to these boundaries, we need we need to be linked– there needs to be connection to properly understand and both work to conserve this region.

And so the Next Generation Sonoran Desert Researchers, or N-Gen, was born from this desire to understand if this community exists. And it started with a single meeting in 2012, which the answer to that question was a resounding yes, this community exists. But we’re fragmented by, in 2012, the increasing fragmentation and strong east to west border of the US-Mexico border was digging in. It’s dramatically increased since then. So that is a huge impediment.

But also an increasing silo-ization, or creating of boundaries, across areas of research or disciplines. So trying to bridge the border and to link ways of seeing the world is really where N-Gen was born. And from that one meeting, it started a movement of creating a platform for collaboration.

IRA FLATOW: Michelle, did you decide to become part of this research collaborative because you agreed with this mission?

BEN WILDER: Certainly, yeah. I was really excited to see a much broader community. I joined N-Gen when I was a PhD student. And I was based in Mexico City, doing my field work in Baja, California, and feeling a little isolated actually because there weren’t a lot of people in my physical location who were working in the same area. So being able to connect with a much broader community with the same passion for the desert and the sea was just extraordinary.

IRA FLATOW: Ben, you talked about N-Gen, and you used the term “interdisciplinary research.” Talk a bit more about what that means.

BEN WILDER: I think these terms, “interdisciplinary,” and then I’ll use “transdisciplinary” here too, are honestly a bit jargony. But when I really had them broken down for me by my colleagues that we were creating N-Gen with, it really honestly shaped– helped transform the way I approach science in my career and almost how I go about my life.

And so what I mean by this is interdisciplinary is trying to use different disciplines or perspectives to understand a question. Let’s say, you go out to try to understand what diversity exists in a region. This is a very important aspect that N-Gen leads in is trying to fill the gaps of knowledge. And so you have a botanist, someone looking at the plants, an entomologist looking at the insects, and maybe even have a geologist. But each person is staying within their own space, their disciplinary practice. But you’re talking across those.

One of the things that N-Gen really strives to– and where the magic really happens– is a transdisciplinary approach. And what that means is putting on the lenses of someone else’s view of the world and incorporating that into your own approach.

And so I’m a botanist by practice, but I’m going out with a geologist. And I’m putting blinders on and I’m not looking at the plants. I’m trying to look at where the faults are or what rocks make this up. And then, lo and behold, now I understand why the plants are growing there.

But even beyond that, it’s merging with the social practice. And one of the things I love working with Michelle is her background is with social science. And my goodness, when we’ve worked on projects, Michelle would bring up ideas that I have never even considered because it’s not how I’ve been trained or I don’t factor in it. And I realize that, oh, my goodness, thinking about– especially in conservation efforts– what we need to be factoring in is so much more than just the biological.

And so it’s talking across disciplines, across worldviews, and really merging those that elevate us to another plane– a higher plane– that makes so much more possible that otherwise is not.

MICHELLE MARIA EARLY CAPISTRÁN: In terms of transdisciplinary also– and I totally agree, it’s definitely jargony– but I think it can be summed up pretty well as looking at multiple academic or scientific disciplines, plus non-academic collaborators. So I think the magic also happens in integrating people who aren’t trained in conventional present-day science. So that includes Indigenous communities, rural communities, different people from different sectors.

So N-Gen isn’t just academics. It’s also nonprofits, it’s also government– all of us participating as individuals, non-representation of our institutions– but people with all sorts of different experience in different aspects of how conservation happens on the ground, as well as in the lab.

IRA FLATOW: I want to talk more now, Michelle– a little bit more about the Gulf of California. I hear it’s a really cool place to study. When most people think of desert ecosystems, they’re not thinking about something that’s along the sea. So tell us about what’s going on there a bit.

MICHELLE MARIA EARLY CAPISTRÁN: Yeah. Well, it’s incredible. I mean, the Gulf of California is a national treasure of Mexico. It’s one of the only seas, if not the only sea, that’s entirely within one country’s jurisdiction. So that makes it very important to protect.

And I just remember the first time I saw the Gulf of California, when I was still in grad school. It was just mind blowing seeing cactus growing next to the ocean. That was something I’d never seen before– you know, used to palm trees.

And seeing this contrast of this very arid land– I think “arid” is perhaps– has kind of a connotation that’s not great– because this land is incredibly rich and biologically diverse and just has this extraordinary amount of life. But then, you turn to the oceans, and it’s just absolutely astounding. I mean, there are five different species of sea turtles. There’s all sorts of different species of whales, dolphins, porpoises, sea lions.

And what’s really incredible is it’s a place where cold and warm water meet. So you get maximum biodiversity in these places where different ecosystems collide with each other, what scientists call ecotones. So the Gulf of California is a really important ecotone in terms of the ocean. It’s where the Tropics meet the temperate waters.

So it’s a place where you can see tropical fish and sea lions together. I think it’s probably the only sea in the world that has these type of conditions. So it’s just an incredibly, incredibly rich and special place.

IRA FLATOW: Now, let’s talk about the green sea turtle. Because I know you study that in particular. And your work incorporates the knowledge of local communities who live along the sea. And they bring some knowledge that you can use with them, right?

MICHELLE MARIA EARLY CAPISTRÁN: Absolutely. Yeah. I hesitate to say I do it. It’s collaborative. Taking a couple of steps back, green turtles are a very culturally important species in the North of Mexico. So both Indigenous and non-Indigenous communities have used them as food, as medicine. They also have a lot of meaning in art. They’re what’s called a cultural keystone species. It’s a species that has a very special, pivotal role in how community relates to the natural world.

So in my case, I work with communities on the Baja Peninsula side– rural communities. So these communities, for hundreds of years, caught turtles for subsistence purposes. They did so sustainably, with very limited technology. And in the 1960s, more or less, there started to be a commercial demand for sea turtles, when the cities along the US-Mexico border started to grow.

So that matched up with a time when there was a lot more fishing technology– outboard motors. There were highways built that allowed that demand to be quickly supplied. And sea turtle populations just dropped dramatically. So now, green turtles have been protected in Mexico for over 40 years. Their populations are growing enormously. It’s really great news.

Basically, the work that I do is trying to talk with the people in the communities, especially the elders, who were able to witness the sea turtle populations back in the 1950s and ’60s, and try to reconstruct what the population levels were back then, basically, by interviewing them and learning everything possible.

Because these guys they’ll forget more about the ocean than I’ll ever possibly know. They’re people with 50, 60 years of experience on the water that just is invaluable. It’s extremely, extremely important knowledge that’s not written down in any books. And when they’re gone, humanity loses that forever.

And this is something that’s happening not only in the Gulf of California, but around the world. So I have the enormous honor and responsibility of being able to work with people, to learn from them, and hopefully help their knowledge be a fundamental part of how conservation science is carried out.

Because, unfortunately, historically, conservation has a lot of colonial baggage, where conservation measures or policies are implemented with varying degrees of exclusion. So that’s something that needs to change.

IRA FLATOW: This is Science Friday, from WNYC Studios. If you’re just joining us, I’m talking with Ben Wilder and Michelle Maria Early Capistrán about the Sonoran Desert ecosystem.

Ben, we talked about how vast the Sonoran Desert is. Can it be viewed as one ecosystem?

BEN WILDER: So I think it can be conceived of as one ecosystem with an infinite number of parts. And one of the best ways to think about it as a singular entity is actually how an early founding scientist of the concept of the Sonoran Desert forestry stated that the Sonoran Desert is area of singular biological unity surrounding the Gulf of California.

And so that just speaks to the importance of this body of water that Michelle so beautifully described as just a keystone element that so much of the life in the Desert connects to. And one of the simplest ways is the majority of the precipitation we get in our summer rainy season– the summer monsoon or the Mexican monsoon– is derived from the Gulf of California. And that makes the majority of the entire Sonoran Desert tick.

IRA FLATOW: And so what would you like to know more about it that you don’t know? I only have a few minutes left, so let me ask both of you. First, Ben, tell me what you need to know or would like to know more about what you study.

BEN WILDER: Oh, my goodness. That is probably one of the harder questions you could ask. Because the beauty is that anywhere you dig into– so I continue to work on cacti– and there’s the description Michelle said of seeing cacti next to the desert– that captured me, and that’s one of the main areas of focus. And 25 years in now, I feel like I barely understand anything. And one question leads to another.

And so looking at the connection of the diverse waters and how birds bring nutrients on to land and fuel the cacti’s growth and then how that ripples out through the rest of the ecosystem.

IRA FLATOW: And Michelle, you?

MICHELLE MARIA EARLY CAPISTRÁN: I would definitely agree with Ben’s take. There’s always going to be more and more and more to learn. I think it’s inexhaustible. I would say, at least for me personally, it’s looking into, what is the future potentially going to be like? Because this is also an area that has all sorts of different human pressures. Climate change is going to have a whole bunch of effects that we really don’t know yet what they’re going to be.

And I think we need all hands on deck right now to face those challenges. And hopefully do it in a way that’s more equitable and more just.

IRA FLATOW: Are the green sea turtles– are they going to migrate because of climate change?

MICHELLE MARIA EARLY CAPISTRÁN: Certainly, in the Pacific, we’re seeing green turtles moving farther and farther north. So the work I’m developing now is on the Pacific side, partly in the Sonoran Desert. And what we’re trying to do is look at what fishers and what coastal communities know about green turtle habitats, and, basically, use them to map where green turtle habitats are today and then project that onto the future and see where they might be in 30 or 50 years.

So we are seeing more and more turtles in Southern California, for example, which seems to be a new phenomenon. The populations are really taking off. And so yeah, we’re going to see a lot more turtles interacting with urban areas, for example, or just moving into places where they’re not expected. So a lot of changes are going to happen.

Also, sea turtle sex determination depends on temperature. So above a certain temperature, they’ll be either male or female. So one problem that’s starting to happen is that a lot of populations are no longer producing enough males. That’s going to be a big problem in the future.

IRA FLATOW: We’ve got to end it there. We have run out of time. Such fascinating work. I’m jealous of you guys being able to go study all of this stuff.

BEN WILDER: Come and visit, please.

MICHELLE MARIA EARLY CAPISTRÁN: Any time.

IRA FLATOW: Absolutely. I want to thank my guests, Ben Wilder, director and co-founder of Next Generation Sonoran Desert Researchers, based in Tucson, Arizona; Michelle Maria Early Capistrán, David H. Smith conservation fellow at Stanford and board member of the Next Generation of Sonoran Desert Researchers. She’s based in Monterey, California. Thank you, both, for taking time to be with us today.

BEN WILDER: Well, thank you.

MICHELLE MARIA EARLY CAPISTRÁN: Thank you.

Copyright © 2023 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of Science Friday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/