Can A Microbe Conservation Movement Take Off?

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Hi, I’m Flora Lichtman, and you’re listening to Science Friday. Today on the show, a team of scientists is trying to jumpstart a global conservation movement on par with saving the rainforests or protecting the oceans. Actually, it might even be more ambitious, because the target of their quest is invisible everywhere, and mostly something we try to hand sanitize away.

These scientists are trying to save the microbes. Leading the effort is microbial ecologist Dr. Jack Gilbert from the Scripps Institution of Oceanography. He’s the co-lead of the newly formed microbial conservation specialist group under the IUCN, the International Union for Conservation of Nature. Jack, welcome to Science Friday.

JACK GILBERT: Thanks, Flora. Great to be here.

FLORA LICHTMAN: OK, why this quest?

JACK GILBERT: Microbes have been around on this planet for 4 billion years. The epicenter of all microbial– of all diversity on the planet. They make the biggest impact. They have the key role of driving all of the climate action on the planet. All of the gases, all of the nutrients go through them. They’re also the biggest biomass. They outweigh everything that you can see with your eyes. So we figured that they might be important for that reason.

FLORA LICHTMAN: That they deserve a seat at the table.

JACK GILBERT: They deserve a seat. And conservation has done a great job over the last 150 years of making sure that the animals and plants have a protected status. So we wanted to put microbes in that same category. But we also think those microbes can play a fundamental role in improving the conservation strategies for animals and plants as well.

FLORA LICHTMAN: I mean, is that why you care, Jack?

JACK GILBERT: No, I care because I love microbes, and I’m a bit of a microbe nut. The very first thing I ever wanted to do was culture things and grow them and see them and play with them. I mean, to me, that’s my playground. They’re really cool. And the diversity and their functional ability and their adaptability is just so mind blowingly awesome that it makes me excited to be able to investigate and strategize and explore that world, and then leverage it to make sure the planet stays safe.

FLORA LICHTMAN: Are we tracking the loss of microbial species?

JACK GILBERT: We are not. There is no current red list strategy. For some fungi, there are, but for the vast majority of bacteria, archaea, viruses, absolutely not. And we think that’s a problem.

FLORA LICHTMAN: How do we know that we’re losing species? How do this is a problem if we’re not tracking it?

JACK GILBERT: This is the very difficult question. It’s very hard for us to do a full survey. When you’re talking about bacteria and archaea, you have probably close to 100 billion species, maybe a trillion strains of these organisms, subspecies level. And they are everywhere and invisible, as you say. So tracking their impact is extremely hard. We have to do it by proxy and see what’s actually happening in the world.

So, for example, it’s quite obvious that the vast majority of microbes that might be super evolved to live inside a particular species will go extinct should that species go extinct. So I think the microbes living inside an otter species or a panda. They will go extinct when that animal goes extinct. So that’s a problem.

But we’re finding that certain species might be starting to disappear because their environment is changing. So for example, really important species like phototrophs living in the ocean. These are cyanobacteria that produce all the oxygen on our planet. They appear to be disappearing because the oceans are getting warmer, and they can no longer survive or thrive or adapt in that system.

So one of the great examples that we know is a big problem for humanity is the reduction in the biodiversity of a species called bifidobacterium longum infantis. This is a species that lives inside our bodies, especially when we’re infants, and is uniquely evolved to degrade and ferment all of the breast milk sugars that are present in human breast milk. This food that feeds our babies and makes our babies’ immune systems become incredibly strong is entirely dependent upon the ability of this species to ferment it into other products, which our baby’s body needs as it’s developing and growing.

So this species is disappearing in the developing world. We barely find it existent at all in the United States, in China now, in Europe, it’s disappearing. So if we can’t conserve the biodiversity of bifidobacterium and use it to add it back into children’s lives, then we’re going to have chronic diseases that spread throughout our populations and make our lives a lot worse.

FLORA LICHTMAN: That’s shocking because of course, there’s no shortage of humans and human babies.

JACK GILBERT: Right. We think it’s intergenerational use of antibiotics, changes in feeding habits, even changes in how we live our lives. We don’t tend to coexist in family units with our grandparents and our grandchildren living side by side now. And that, we believe, is reducing the transmission of this species.

FLORA LICHTMAN: Huh. Well, what are the other threats to microbes?

JACK GILBERT: So the threats to microbes are exactly the same threats that we see to all other species. Deforestation, pollution, runaway climate change, changes in weather patterns, agricultural activity. All of the practices which damage our natural environment are also damaging the microbes. But when we eradicate the microbes, our ability to restore those ecosystems is severely impeded.

So think about mangrove swamps. When you wipe out a mangrove swamp, you can’t just replant the trees and expect them to be able to grow. First you have to rehabilitate the soils and the sediments those trees grow in by adding bacteria back into that environment. Then the trees can survive.

FLORA LICHTMAN: I mean, habitat loss, urbanization, climate change, these are the usual suspects in so many biodiversity loss problems. Why do microbes need their own protections? Can’t we just do the things that we’ve been trying to do for macrofauna or plants?

JACK GILBERT: Yeah. So I call them macrobes, everything that’s large and not a microbe.

FLORA LICHTMAN: Macrobes, I love it. Yes, of course, because it’s our macro bias that we would call them microbes at all.

JACK GILBERT: Exactly. So one thing one of my colleagues once said was if we’d had conservation of microbiology and the integration of microbiology into the conservation strategies that we’ve been playing with for the last 150 years, we might be a lot further ahead in being able to conserve and preserve the macrobes around the world.

FLORA LICHTMAN: OK, so what do you do differently for microbes that you don’t do for macrobes? How does this strategy change?

JACK GILBERT: So it’s interesting. We’ve been exploring strategies such as putting a fence around a forest, even preserving the embryos and eggs and sperm of these animals and plants in frozen banks, frozen zoos. And you can think about the seed bank up in Svalbard as a great example of that. We’re doing the same thing for microbes. We’ve started a microbiota vault that allows all of the world’s microbial collections to be preserved in another environment. That means that we can use them later on.

FLORA LICHTMAN: OK, so a microbe vault. Are there other strategies? Give me another example of how microbe conservation would work.

JACK GILBERT: So a great example of how microbe conservation would work would be ensuring that we understand where microbes are under threat and that we put in place strategies to facilitate their conservation. A great example of that is desert soil crusts. These are living environments that you can’t see with your eyes, but they actually stop all the dust in deserts from blowing up into the atmosphere.

And they form these biofilms that live on the surface of these deserts, and they stop all the dust and dirt from getting into the atmosphere. These desert soil crusts are under threat. They’re not seen by humans to be important, so people tread on them, they crush them, they develop on them, and they are being destroyed by runaway climate change. So we need to conserve those environments.

FLORA LICHTMAN: Jack, last time we talked, you were swabbing toilet seats in the name of your love of microbes. Are you still just swabbing everywhere you go?

JACK GILBERT: Hey, if you don’t swab somewhere, you don’t what you’re missing, man. That’s really important. Yeah, and part of this conservation management strategy is to go out into environments and track down what we don’t know. What you can see with your eyes or the plants and animals are just the tip of the iceberg.

FLORA LICHTMAN: How does this play at conservation conferences? How do your colleagues view your work?

JACK GILBERT: It’s taken a little while for us to convince even some of the conservation teams that microbiology could be an important part. Even other microbiologists are telling us that, well, you don’t really need to conserve microbiology, because it evolves so quickly. They have very short generation times. They can adapt. They’ve adapted to every single one of the major extinction events.

FLORA LICHTMAN: Is that wrong?

JACK GILBERT: Well, it isn’t, but my point is so have the other animals and plants. If you wiped out all of the rhinos on the planet, in another 100,000 years or a million years, something would evolve to fit that niche. The same is true for microbiology, just on a shorter timescale. And so what matters in conservation is why something is important to people in order to conserve. If it’s not important to a human, why are we bothering to conserve it? It’s a bad way of saying it, isn’t it? Makes us sound a bit dystopian.

FLORA LICHTMAN: I think your love goes a long way, Jack. I think people underestimate other people’s love of things as a motivator.

JACK GILBERT: Yeah. E.O. Wilson once said that the reason biology was important to people is because they fell in love with it. He called it biophilia. And I think the same has to be true for microbiology, microbiophilia, if you will.

But the idea is that we conserve something because it means something to humanity, whether that’s because it provides an ecosystem service, like pumping oxygen into the atmosphere, or whether it’s because it can make our soils more fertile and therefore produce more food to keep our population safe. These are important components of why microbiology could drive forward a new revolution in making this planet more sustainable and supportive for humanity and for the rest of biodiversity. But it all starts with the microbes.

FLORA LICHTMAN: Yeah, I also think that scientists underuse the heartstrings. I’ll just say that.

JACK GILBERT: Yeah. Please conserve the microbes. They’re dying.

FLORA LICHTMAN: I think you need a panda, a microbe panda of this movement. The face, the charismatic mini fauna that people are going to fall in love with. What should it be?

JACK GILBERT: My favorite bug is faecalibacterium prausnitzii. This is an amazing organism that lives inside the guts of us and other species, and plays a vital role in our own health. There’s also brilliant species in the soil. I mean, this is impossible to choose from my own children. You can’t ask me to do a Sophie’s choice on which one’s more important. Microbes are just incredible, and the diversity is just so vast and unbelievably important.

FLORA LICHTMAN: Dr. Jack Gilbert is a microbial ecologist at the Scripps Institution of Oceanography in San Diego. He’s also a co-chair of the IUCN’s microbial conservation specialist group. Jack, thank you for joining me today.

JACK GILBERT: Thanks, Flora.

FLORA LICHTMAN: Today’s episode was produced by Rasha Aridi. I’m Flora Lichtman. Thank you for listening.

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