Can We Go Back to Eden?

: Emma Marris: Science cannot give us shoulds. It cannot tell us whether it should be a wetland or a prairie. It cannot tell us what year we should have as the cutoff for whether a species is native or not. Native. These are all human values, and we just need to admit that now, once we do admit that, that means that the scientists who are involved in restoration no longer have the ultimate authority. They are just one voice among many, all other stakeholders landowners, people in the neighborhood, indigenous groups. All of these people now have also an equal voice in this large conversation about what our goals should be. And that can feel very uncomfortable, because that means that some people you disagree with might have different ideas than you.

00:00:49: Volker Hahn: Welcome to Inside Biodiversity. This podcast is hosted by iDiv, the German Centre for Integrative Biodiversity Research. My name is Volker Hahn. I'm head of the communications unit at iDiv and my guest today is Emma Marris. Emma is a science writer who specializes in biodiversity and conservation. Her work has appeared in outlets such as The Atlantic, The New York Times, or Nature. She's the author of two books on conservation issues, Rambunctious Garden and Wild Souls, as she states on her website. Emma's core interest is in human relationships with the non-human world. Today, we will discuss what we value about nature, how these values determine our goals in conservation and restoration, and which metrics can guide us in achieving these goals. I'm very happy to have you on the show, Emma. First, can you tell us how you became a science writer and why do you focus on biodiversity and conservation?

00:01:51: Emma Marris: So I grew up in the Pacific Northwest and I was always very interested in plants in particular. Um, and I became a science writer as a career. And when I first started, I was interested in writing about all the sciences. I wrote about astronomy, I wrote about geology. Um, but I found that I enjoyed reporting about ecology and conservation the most, because I loved going into the field with researchers and just getting outside and going to all these different ecosystems. So I came into thinking about conservation as a reporter who had not been trained as a conservation scientist and who also who had not grown up sort of self-identifying strongly as an environmentalist. I really loved plants, but I wasn't sort of the kind of person in the Pacific Northwest who was chaining myself to trees. I was sort of more of a city person. And and I think that in the end, that has been a helpful, um, beginning for me because I. didn't get indoctrinated in some ways into some of these cultures, and therefore it was easier for me to see, uh, assumptions that had been baked into conservation and ecology, uh, because I was coming from the outside, so to speak.

00:03:12: Volker Hahn: So it was easier for you to take a step backwards and have a more distance view on. Yeah. As you say, some of the assumptions in environmentalism and maybe also in biodiversity research, because many biodiversity researchers feel strongly for the issue that they're researching.

00:03:32: Emma Marris: Right. And and they, you know, in the a young period in their lives, they learned about, for example, how to sort of measure intactness in an ecosystem. And they absorb that. And then I show up, you know, having never learned this, and they say, well, over here is a more intact ecosystem. And I'm like, what does that mean? Because I've never heard of that before. So it helps me see things with fresh eyes.

00:03:53: Volker Hahn: Yeah. Yeah. We'll question some of these, uh, wordings and some of the measures that we use for conservation and restoration in this conversation. And maybe the first word we can talk about is wilderness. And this is a word that or a concept that you've written about in your first book 14 years ago. It's called rambunctious, rambunctious garden saving nature in a post wild world. So post wild is this world not wild anymore?

00:04:26: Emma Marris: Well, there's really no part of the world that is not influenced by people, at least influenced by people. There may be some parts of the world that are not currently managed by people, but they are like everywhere else, dealing with climate change and the movement of species and the changes on adjacent parcels of land. And so there's really nowhere that is not influenced by humanity.

00:04:49: Volker Hahn: So you make this differentiation Between being influenced and being intentionally influenced. Is that something you think that can help us when we try to identify? Ecosystems or states of ecosystems that we we would like to conserve or or restore? Can that be a guiding principle for conservation?

00:05:13: Emma Marris: So I think that the word wilderness is probably too tangled up with sort of colonial ideas about pristine states of nature existing. And so I don't really think that that term is useful anymore. Um, however, I do think that there is some kind of value that is present in places that are not being managed for human purposes. But I think we can use other words to talk about that, like autonomy, maybe. Um, and I do think that that is a valuable thing, that we should make sure that this isn't a planet where 100% of the land is being actively gardened. Um, some of it should be, uh, a little rambunctious.

00:05:52: Volker Hahn: Okay. So we'll we'll talk about autonomy later. We'll also also talk about ecosystem integrity in this podcast. In the previous episodes, we had a lot of discussions about the metric biodiversity and species richness or local species richness in particular. And researchers have found that this is highly variable depending on the ecosystem, depending on the taxa you're looking at, the time span you're looking at at, it can go up or down or stay the same. And maybe it's not always something that is worthwhile protecting per se. For example, one researcher said that if you chop down an old growth forest, you might get or you will get more species. And I guess many would agree that this is not desirable. So species richness and biodiversity per se might not be always a guiding principle for conservation. And then another metric or measure that came up as an alternative to that was ecosystem integrity. Can you go a little bit deeper into that? What is it that people actually mean when they talk about ecosystem integrity, and what role does it play in conservation?

00:07:14: Emma Marris: So I believe that there's a widespread tendency in conservation and conservation science to kind of add naturalness to everything else. Uh, I think that there's this fundamental, um, value of naturalness defined as not having been influenced by humans. And it's so fundamental to the field that it tends to leak into all of these other concepts. Um, and I think it's also a mistaken value, because I do think that humans are a part of nature, that we are not aliens from outer space. So integrity is a great example here. In many cases, integrity became more important as a value, as a replacement for naturalness or for historical baselines, which began to be criticized because they were often pegged to the moment of European arrival in a system. And so, um, those values were sort of quietly shelved and replaced by integrity, which definitely sounds more scientific, but it's a little it's not sort of obviously clear what it's measuring. And when you look at the definitions and sometimes you have to kind of go 2 or 3 citations back, you know, like unappealing and onion, you find that typically integrity means how similar is the ecosystem to a reference ecosystem, which is again usually either a historically defined system or a system that is just believed to have as little human influence as possible. And so at the center of the onion we find naturalness. Yet again. It is just a sort of a fancy sciency sounding way of saying it is a natural ecosystem that hasn't been affected by humans. And I object to this because I feel that this is a way of obscuring that. We are, again, talking about desiring that ecosystems be as natural as possible, but making it sound very scientific and sort of quantitative.

00:09:12: Volker Hahn: But you said before that you would appreciate if there were some ecosystems that we would leave alone, but then taking management out of an ecosystem would be some, in your opinion, be something different than an ecosystem being natural. Is that correct?

00:09:32: Emma Marris: Oh, absolutely. I mean, I think most ecosystems that are rated as having excellent integrity require a lot of work because typically these are ecosystems that look the way they did before. Human influence. Right. That's that's what's desired in the community. And because of climate change and land use change and the movement of species that's really difficult to maintain requires a lot of resource inputs and time and money. Whereas if we actually let ecosystems alone and let them go on their own way, we will find them changing quite rapidly in response to all of these kind of larger forcings. Um, the so, you know, I think that an autonomous ecosystem or an ecosystem that isn't managed for human desires is often, uh, very surprising looking, and sometimes it's considered not very desirable by a conservation community because it's going to be filled with non-native species. It's going to have new assemblages. Uh, it's maybe even going to be acting in a biogeochemical way that's new and different, and it's typically going to be seen as a failure or something that's undesirable.

00:10:43: Volker Hahn: That reminds me of this concept of rewilding, where the idea is that you let the processes run in that ecosystem. Maybe you help with the start by reintroducing some some herbivores or restoring trophic integrity, bringing in predators, etc.. What do you think about that concept?

00:11:06: Emma Marris: Well, I think that, again, is a word that people tend to use kind of in many different ways to describe many different styles of, of, I don't know, this broader category that we might think of as just restoration in general, which is again, restoration implies going back. But let's say restoration is the large category of ecosystem management. Not for instrumental purposes, but for sort of conservation or purposes and rewilding. As you say, there's lots of different ways to do it. Europeans love to put cows on the on the landscape and say it's wilder now. And from an American perspective, that looks weird because we were always complaining about overgrazing. And so we like to put carnivores on the landscape and say, okay, now it's wild. But I mean, I think all of them are just different ways of nudging the landscape towards something that we like better. Um, fundamentally, these are all about satisfying our desires for a certain landscape states. I do think that letting ecosystems truly sort this out for themselves, at least in some places, has some value just really just seeing what happens. And I actually think that there are some places where that this is being done, and sometimes it's almost done on a very small scale as a kind of an art project. In fact, in Germany, there's some beautiful parks where nature has been allowed to reclaim older human sites. And it's truly fascinating to see how they how they evolve over time.

00:12:35: Volker Hahn: There's another facet of ecosystems that some people have taken into focus and think that's also important, which is the functioning of an ecosystem. So biodiversity researchers investigate the the different functions like like water retention, like carbon sequestration in ecosystems. Element flows like nitrogen, for example. What do you think of that? Is that important or is that in the end always up to to us humans what we value more?

00:13:11: Emma Marris: I mean, I think that's it, right? It doesn't matter whether we're talking about functions or whether we're talking about what list of species we want there to be on the site, or whether we're talking about, you know, how we want it to visually look. It's always about human preferences. And and I think that the real missing piece for a long time has been admitting that, um, sometimes you'll see people talk about well functioning or poor functioning, degraded functioning, high functioning, low functioning. These are all ways of talking as if there is one set of functions or one level of functions that is correct, and all of the other types of functions or levels of functions are incorrect. But this kind of correct functioning must be again set at some sort of baseline or some sort of reference state, which is ultimately arbitrarily chosen on the base of human desires. So I'm not saying that we should let the entire world go and that we shouldn't do any kind of restoration activity. Far from it. What I'm what I'm thinking that we should do to make things more transparent is to simply admit that, well, over here we are trying to maximize biodiversity. And over here we would like this to stay a forest and not become a grassland and not become a forest. And over here we would really like to have some grazers, but it's always what we would like, not what that the ecosystem somehow objectively demands.

00:14:35: Volker Hahn: So that basically means that all these metrics that we've talked about are important in the sense that they can help us achieve the goals that we set as humans with our values, but not in the sense that the metrics per se provide an objective measure what to aim for. But we we as humans, we set the goals and those different metrics depending on how we value them and how important they are in a specific ecosystem or area. They can they can guide us and help us monitor whether we are actually on the way of reaching these goals.

00:15:23: Emma Marris: Yes, exactly. You know, I think sometimes when I criticize the use of historical baselines, people think that I'm saying that we should never do environmental history, for example. And that's not true at all. Because that's incredibly useful information about what? What this site has looked like in the past, what it could look like in the future, gives us a menu of options to consider. But ultimately, science cannot give us shoulds. It cannot tell us whether it should be a wetland or a prairie. It cannot tell us what year we should have as the cutoff for whether a species is native or not. Native. These are all human values, and we just need to admit that now, once we do admit that, that means that the scientists who are involved in restoration no longer have the ultimate authority. They are just one voice among many, all other stakeholders landowners, people in the neighborhood, indigenous groups. All of these people now have also an equal voice in this large conversation about what our goals should be. And that can feel very uncomfortable, because that means that some people you disagree with might have different ideas than you.

00:16:33: Volker Hahn: Well, it sounds like democracy.

00:16:34: Emma Marris: Yes. Which is, as we know, terribly messy and inconvenient and requires way too many meetings. But it's the best thing we've got, and we better hold on to it with our bare with our, you know, fists.

00:16:46: Volker Hahn: Yeah I agree. Um, so you've you've mentioned baselines and we haven't talked about this. So you have criticized especially for, for the North American continent, but also for maybe Australia setting the baseline of colonization for ecosystems. And one of the arguments you, you bring forward is that even before that time, the people living there actually did have, even though they were not many in comparison to today, uh, had huge impacts on the the ecosystems. Can you elaborate a little bit on that?

00:17:25: Emma Marris: Yeah, sure. So I'll talk most about North America since I'm most familiar with that, although they're similar patterns in Australia and New Zealand. You know, Africa, South Africa. But in North America, we also have this pattern of glaciers that, you know, have come and gone over the years. Um, they we have glacial ice sheets coming halfway down the continent, and then they go back up again. And one thing that's quite interesting to me is that every interglacial looked a little different. The distribution of plants on the landscape and presumably the animals that that live amongst those plants was a little bit different every time. Sometimes two trees would be together and sometimes they'd be separate. And so it kind of shows that, uh, there was no one version of Ice Age Americas. Uh, there were many versions. And then, of course, uh, humans show up on the scene very long ago. Uh, we still keep pushing back the dates, but ultimately, humans show up on the scene kind of as soon as the last glacier retreats. They're sort of walking through the soggy landscape of of the ice retreating, and they immediately begin having large impacts on the land. So there's really no day where you have a kind of a pristine, perfect North American or South American ecosystem that you can then use as a perfect baseline for all time. It just doesn't exist.

00:18:51: Volker Hahn: One thing that did change with the European settlers, and maybe much more later on, is that they introduced, deliberately or not deliberately. They introduced new species into ecosystems and whole continents that were not there before. Among conservationists, many see that as huge problems. And I think in some cases that's also the case that some introduced species can Become invasive and make problems. But that is not a general rule. And you're advocating we should recognize that not all alien species are a problem and that conservation should accept introduced species. Is that correct?

00:19:37: Emma Marris: Yeah. Again, it really depends on what your goal is for any particular landscape or, or freshwater or, you know, piece of area that you're discussing. So if your goal is to have it look like it did in the past, and for some areas we might want that goal, then by all means, to achieve that goal, you would want to remove any species that weren't there at that time. But I think that's going to be increasingly difficult. And I also don't think that, you know, I think there's this assumption that in all places, introduced species reduce biodiversity because they're such this grave threat. And I don't think the science supports that. I think that, um, certainly there are specific situations like predators on small islands and plant diseases like, you know, chestnut blight and so on, where you can actually get extinctions because of introduced species. But I think the vast majority of introduced species on continents do not cause extinctions, especially not plant introductions. I have really looked for an example of a continental plant introduction that has driven something extinct, and I cannot find one. Maybe your listeners can, uh, can write in. Um, so I think that, um, you know, we have created this very emotive language around introduced species calling them invasive, which kind of implies that they're doing it on purpose, that they're malicious, bad actors who want to cause trouble. And then we, you know, in some cases, we rally the public to kill them and to and we try to get them to, to feel negatively towards them. And I think this is all very bizarre and problematic because the movement of species is, um, something that's been happening all throughout time. I mean, how do you think species, any species, got to islands in the first place? Species move around. Um, in North America, the bison came around the same time as humans did. So should we kick it out as an invasive species? Um, the I think the reason for all of this kind of heated rhetoric is that when people move species, it is again considered unnatural. And we come back to this insidious naturalness that oozes into all of the other values and conservation. Um, again, we only think biodiversity is valuable if it's natural biodiversity. And we see introduced species as unnatural biodiversity, and therefore they somehow don't count. Um, and I just don't think it's a very scientific way to look at it.

00:22:12: Volker Hahn: Mhm. Very interesting. I'd like to add that there's been a lot of research that shows that there are many plant species that are threatened in their native range, but they have colonized in other regions of the planet, and those regions where they are alien might actually be important for for their conservation, because at home they are threatened. So that's maybe an argument for for accepting alien species as well. However, you said there is heated rhetoric about this. And in one of your articles you write that you've been called an invasive species denialist. Can you elaborate on that? Is that really so, so heated? And and have you been harshly criticized for some of the positions that you have?

00:23:04: Emma Marris: Yeah, I mean, it's interesting to see this because, uh, I was so shocked when I showed up on this list of invasive species denialists alongside many other journalists and writers and other scientists who have. Who have suggested that maybe this sort of blanket condemnation was a little bit, a little bit much. I don't think that this is a helpful way to look at this. It's obviously, um, kind of a piece of rhetoric that was copied from from the climate change debates, where people who denied the climate change were happening were seen as climate change denialists. I think with the introduced species debate, there's no question that there that there is, you know, a real scientific debate about whether or not invasion biology is as a framework is the right way to go in terms of achieving all of our conservation goals. So I think the analogy is a false one, but I also think that just the fact that it got to this point shows that conservation is a very value laden field. I mean, people don't get into conservation and ecology because, I don't know, they just couldn't figure out what to do with their lives. And so they decided, well, I guess I'll become a conservationist. Like, that's not the route people go because they are passionate, because they deeply care about other species, landscapes, nature. It speaks to them on a moral level, on a spiritual level. Even so, this is not a normal, uh, field of endeavor.

00:24:31: Volker Hahn: This is like a deeply.

00:24:33: Emma Marris: Value laden one. And I think it's just really important for us to acknowledge that, because sorting out what our values are and being very honest and transparent about them will make us more effective at achieving our goals.

00:24:46: Volker Hahn: But do you think that the discourse on conservation and what we should aim for and heterodox positions like yours, is that a healthy discourse? I feel like in the climate debate it's often not. There is a lot of manicheism. What's your assessment for the biodiversity debate?

00:25:09: Emma Marris: I think we're in a much better place now than we were when Rambunctious Garden came out. I think there's a lot more discussion about these topics, a lot more kind of thoughtful critiques of historical baselines and so on. I do think that a lot of these ideas, many of which began in the humanities and history and environmental studies, are being taken more seriously in the sciences now. And I think that's really great. Um, you know, I think that over time, as the world changes, as ecosystems continue to change very markedly in response to climate change and other large scale forces, it will simply be impossible to continue to use a kind of a 1970s conservation worldview in which the goal is to make everything look like it did in 1492 or 1850. That's just going to be so difficult and so implausible that I think we're going to need these more complex, more nuanced frameworks. Um, and and and I hasten to add that there is no one correct goal. I'm not saying that the values that are currently in use are incorrect, and that I've got a better set that I want to sell you. Uh, I actually think that the, you know, these values are always open to debate and discussion. They're going to change through time. And each project or each place may have a different suite of goals that it's being managed for or not managed for. There's no one true answer to all of this.

00:26:40: Volker Hahn: What are your wishes for biodiversity conservation, conservation and for also biodiversity research? What do you think are the most important issues that should be resolved and that should people should focus on?

00:26:57: Emma Marris: I think what I would really just.

00:26:58: Volker Hahn: Love to.

00:26:58: Emma Marris: See is, is people define their terms very explicitly for each project, research, project or management project and also define their goals, you know. Oh, for this site we want it to look like this. Or for this site. Our goal is to make sure that these five species don't go don't go extinct or or what have you. Instead, that step often gets skipped and you'll see people managing, you know, large areas of land or doing research using these vague concepts like integrity or health without even really clearly defining them in terms of that particular study or that particular project. And so we're left with a kind of a mushy understanding of what we're managing for or what we're trying to see. And I think that that can often make us step all over our own feet. You know, we might end up spending hundreds of thousands of dollars killing introduced species because they're non-native. And we just have this basic idea that that's bad, even though really what we want in this site is recreation opportunities, and we want the flourishing of these five native species, and none of them are actually being impacted by those species that we just dumped a bunch of herbicide on. So I think clarity in terms of our values is what I would like to see, and just the acknowledgment that we're not going to be able to make the world look like some kind of Disneyland version of a pre-Columbian, pre-industrial landscape.

00:28:26: Volker Hahn: An environmental debate. There's often a lot of negativity, and people have very bleak visions of where we are going. For example, in the climate debate. And some have criticized this and say there's too much doom in these conversations and we are not doomed. What is your perspective on that issue when it comes to biodiversity and nature conservation?

00:28:55: Emma Marris: Yeah, I'm really unhappy with the way that a lot of people, both scientists and the media, talk about biodiversity change. I have a lot of people in my life who are not scientists or journalists, who feel incredibly hopeless and believe that we are in a phase of extinction that's so profound that there's very little that can be done about it at this point. Um, rhetoric like the six mass extinction has convinced a lot of people that it's sort of too late that, that, that and, um, the way that other scientific products like the Living Planet Index are reported have convinced many people that we've already lost huge percentages of species. Um, so I think there's been some real you know, I understand that conservation biology has always been a crisis discipline and that there's a culture of wanting to get people interested and to convince people of the urgency of action. Um, but after, you know, a generation of intense urgency and emergency communications, we've convinced a lot of people that we're already in this sort of post-apocalyptic wasteland. So I think that that we really need to re, you know, balance our coverage of threats to biodiversity with information about possible solutions and also with realistic assessments of where we are. Obviously, the number of extinctions that are documented, which are close to 1000 is too many. But given, you know, as a proportion of the total number of species on Earth, it is not. We are not. We haven't lost. You know, we'd have to keep these same extinction rates for thousands of years to be really in a mass extinction. And the idea that we're not going to change our behavior thousands of years from now seems implausible to me. Um, I'll just give one example is I have many friends telling me that they're terrified about the decline of insects, which has been so well covered. And many of these studies are quite local, and they're looking at specific agricultural contexts with large amounts of chemical use. But the message that's getting to the public is that all the insects are dead. But you know, one thing that I never see these articles mentioned is that the good thing about the insects is they have incredibly short generation times so that if you can address the threats to them, they could repopulate incredibly quickly. We're not talking about elephants here that, you know, have like a two year pregnancy and only a few offspring at a time. But that part of the biodiversity puzzle is never included in this coverage. There's so much hope, there's so much room for action. There's so much stuff we can do, and it is not too late. And that is not the message that people are getting. And as a result, I think they are really disengaging emotionally from biodiversity. Questions of biodiversity. They think that it's too painful to even contemplate. And this drives me bonkers because I want them back on the biodiversity team.

00:31:49: Volker Hahn: We've covered a lot of topics. We've talked about different metrics of biodiversity and how they can or cannot guide us in conservation and restoration. What is it that if you could briefly summarize, um, what would you like the audience to remember from this conversation in in a week or two from now?

00:32:18: Emma Marris: Not all change is loss. Ecosystems changing is sometimes ecosystems adapting to what we have done, and we can learn from that rather than always trying to undo it.

00:32:33: Volker Hahn: Thank you very much for this very interesting conversation, Emma. I hope you enjoyed listening to this episode. Be sure to follow us on X on Bluesky on LinkedIn, and on your favorite podcast app for feedback, ideas or questions. Use #InsideBiodiversity or email us at podcast@idiv.de.