A Sustainable Future: Prof. Simon Levin, Princeton University, on Ecological Early Warning Systems

 

Why is a multi-disciplinary approach key to addressing biodiversity loss? Listen to Jason Mitchell discuss with Professor Simon Levin, Princeton University, about what’s at stake in the effort to preserve biodiversity loss; how his work has expanded into the sociological, political economy and policy space; and why a common language — a grammar for economic reasoning — is vital for bringing together different disciplines to understand nature.

Recording date: 15 January 2024

Professor Simon Levin

Professor Simon Levin is the James S. McDonnell Distinguished University Professor in Ecology and Evolutionary Biology at Princeton University and the Director of the Center for BioComplexity in the High Meadows Environmental Institute. His research examines the structure and functioning of ecosystems, the dynamics of disease, and the coupling of ecological and socioeconomic systems. Simon is a Fellow of the American Academy of Arts and Sciences and the American Association for the Advancement of Science, a Member of the National Academy of Sciences and the American Philosophical Society, and a Foreign Member of the Istituto Veneto di Scienze, Lettere ed Arti, and the Istituto Lombardo. He has over 500 publications and is the editor of the Encyclopedia of Biodiversity and the Princeton Guide to Ecology. Simon’s awards include: the Heineken Prize for Environmental Sciences, Kyoto Prize in Basic Sciences, the Ecological Society of America’s MacArthur and Eminent Ecologist Awards, the Tyler Prize for Environmental Achievement, and the National Medal of Science.

 

Episode Transcript

Note: This transcription was generated using a combination of speech recognition software and human transcribers and may contain errors. As a part of this process, this transcript has also been edited for clarity.

 

Jason Mitchell

I'm Jason Mitchell, head of Responsible Investment Research at Main Group. You're listening to A Sustainable Future, a podcast about what we're doing today to build a more sustainable world tomorrow. Hi, everyone. Welcome back to the podcast and I hope everyone is staying well. So every now and then I do a podcast episode where I kind of feel like I'm in over my head.

This is one of them. I say that because Professor Simon Levin's work cuts across the boundaries and processes of so many different disciplines. Indeed, starting from his early foundational work, developing a theoretical framework for understanding coevolution and genetic feedback, his focus has increasingly spilled over into fields as diverse as epidemiology and infectious diseases to sociology and political economy.

Now, if there's a single thing I think idea I take away from this episode, it's that nature teaches us to act collectively. And to that end, ecology and economics are inextricably linked. It's a theme that over 60 years works to couple ecological and socioeconomic systems through collaborations with many of the great modern thinkers in these fields. So it's great to have Professor Simon Levin, a giant in the field of ecology, on the podcast.

We talk about what's at stake in the effort to preserve biodiversity. How his work has expanded into the sociological, political economy and policy spheres, and why a common language, a grammar for economic reasoning his paper calls. It is a vital for bringing together different disciplines to understand nature. Salmon is the James s McDonnell, distinguished University professor in ecology and evolutionary Biology at Princeton University and the director of the Center for Bio Complexity in the High Meadows Environmental Institute.

His research examines the structure and functioning of ecosystems, the dynamics of disease and the coupling of ecological and socioeconomic systems. He's a fellow of the American Academy of Arts and Sciences and the American Association for the Advancement of Science and a member of the National Academy of Sciences. Salmon has over 500 publications and is the editor of the Encyclopedia of Biodiversity and the Princeton Guide to Ecology, his awards, of which there are many, include the National Medal of Science, the Heineken Prize for Environmental Sciences, the Kyoto Prize in Basic Sciences and the Ecological Society of America's MacArthur, an Eminent Ecologist Awards.

Welcome to the podcast, Professor Simon Levin. It's great to have you here and thank you for taking the time today.

Simon Levin

it's a pleasure to be here with you, Jason, and to spend some time together.

Jason Mitchell

It is loud and clear. So, Simon, I want to set up our discussion with a recent paper you coauthored with Partha Dasgupta titled Economic Factors Underlying Biodiversity Loss. It kind of makes a foundational appeal for, quote, a grammar for economic reasoning and that synthesizes nature, climate and economics. So two questions first. Why is that so important? In second, where would you say that we currently stand in that effort to create a kind of a unified ecological economic understanding of nature?

Simon Levin

Thank you. The reason that's so important is because ecological systems and economic systems are fundamentally intertwined with each other. The late great economist Kenneth Arrow and I, together with Paul Erlich, wrote a paper in a volume honoring Partha Dasgupta in which we explored the interconnections. Ken pointed out that it's no accident that economics and ecology both start with the same syllable eco, which means house.

You're really talking about two very similar sorts of systems in which in developed world interactions lead to macroscopic processes and that these affect each other. And so we've been working together, all four of us together with Carl Jung Mahler and others in an organization known as the Bayer Institute, which is part of the Swedish Academy of Sciences, which is dedicated to bringing together ecologists and economists with the recognition that one could not deal with ecological and environmental problems without taking into account the economic dimensions.

And that one can't be focused on economic systems and socio economic systems without taking into account the environmental and ecological context. And so in 2004, the group of us led by Kentaro, wrote a paper in the Journal of Economic Perspectives in which we developed a concept called Inclusive Wealth, which adds to the normal things that go into measuring the wealth of a nation like GDP by taking into account the natural capital, what its status is, what its status was likely to be given current usage patterns.

And we focused not only on the normal sorts of provisioning services food, fiber, fuel and pharmaceuticals, but especially on the maintenance and regulating factors that maintain biodiversity, habitat and climate. And in the paper that Dasgupta and I recently wrote, we asked what needs to be modified about economic systems, care and trade liberalization, reduction of subsidies for harmful processes to the environment and the development of a global commons.

Now, where are we today? Not as far as we'd hoped when we started the Bayer Institute more than 30 years ago. And by coincidence, Dasgupta and I, together with Carl Vokey, the current director of the Bayer Institute, organized a meeting last week, bringing together a small number of mainstream economists to try to ask the questions What are the next steps in order to bring more economists into the fold?

That, I think, is the challenge for the next ten years. We do have some plans, but it's largely a question of education.

Jason Mitchell

I do want to get in that a little bit more, but I want to sense that a little bit. How do ecological complex systems, something that you're incredibly aware of and familiar with, how do they differ from climate change in that context? I'm thinking about your paper non equilibrium early warning signals for critical transitions in ecological systems. And I guess I'm thinking how to critical ecological transitions effectively.

The sudden shift from one stable state to another across many ecosystems. How do they differ from, let's say, a nonlinear climate shift? You know, for instance, the change in the Atlantic meridional overturning circulation?

Simon Levin

Well, they don't differ from the climate changes, a complex systems problem. And it's fundamentally integrated with ecological systems through multiple feedback loops. For example, Forest Dynamics, which is obviously affected by and in turn affects climate change. I think in terms of critical transitions, whether it's having to do with climate systems or general circulation patterns of the ocean or ecological systems, and we've been focusing on forests, savanna systems and coral reefs and marine systems in general.

And we think in terms of the potential for sudden shifts. There are lots of examples of this. Martin Schaeffer and Steve Carpenter's work on shallow lakes and eutrophication and all of these complex adaptive systems. And what do I mean by that? I mean systems that are made up of lots of individual agents in which patterns emerge at higher levels.

We were all in this field motivated by a paper more than 50 years ago by Nobel Laureate Phil Anderson called More is Different, in which just knowing what the parts are doesn't tell you what the hole is going to be. There are emergent properties. And so the issues that we have to address, whether it's climate change or biodiversity loss or changes in ecological systems, are scaling.

How do we understand the relationship between the small scale and the large scale, the emergence of patterns and the development of statistical mechanics to understand that the formation of pattern in the distribution of species, for example, and the robustness, resilience and critical transitions that might occur. And finally, the conflicts between the interests of individuals and the interests of collectives.

And that's relevant whether one's thinking about ecological systems or whether one's thinking about climate systems, how do we harness the power of individual decision making to incorporate the interests of the collective to deal with these related global problems?

Jason Mitchell

The precautionary principle allows for the adoption of precautionary measures when scientific evidence is uncertain and when the stakes are very high. What is the precautionary principle for ecological tipping points? How should we be behaving? Given how high the stakes are? Is our risk management protocol in your mind for dealing with ecological stress? Is it wrong? If it is, how do we improve it?

Simon Levin

That's a complex question because I'm not sure what our protocol is, but I think one has to take into account in developing the precautionary principle, the cost of being wrong. And I know we'll talk later about discount rates, but this factors very much into this. And not everyone will agree. But we and by we, I mean the economists, Erwin Botha and John List and the ecologist Steve Piccolo and I wrote a paper in Science more than ten years ago which was on a topic we called false alarms.

And it pointed out that if you have a fire alarm in your house, you'd like it to be accurate, but you're much rather have it go off when it shouldn't, then not go off when it should, because the consequences of it's going off when it shouldn't are not high. It's an annoyance, but the consequences of its failing to go off when it really should are enormous.

So I give this as an example, because many people praise their paper and others criticize the paper because it said we were calling for false alarms. That's not what we were saying. We were saying one needed to be precautionary, one needed to make sure that if there was a problem, we were informed about it. I usually get myself up in the morning, but I always set my alarm just in case.

So I'm a big fan. In this case of the precautionary principle. It doesn't mean we should just sit back and and develop these alarms, but we need to refine our understanding of early warning indicators so that we have a better idea when it's safe to do something.

Jason Mitchell

Over the last several years, climate science has advanced concepts like feedback loops, tipping points and early warning systems, all points that you've just mentioned. But I guess can you carry that over to ecosystem tipping points a little bit more given the interconnected nature between climate and in nature? For instance, how close are we to experimentally studying the effects of tree change, for instance, in ecosystems with tipping points?

Most ecological tipping points that have been studied in experimental microcosms at the population point with a single species, but that doesn't capture ecosystem scale, tipping points.

Simon Levin

Actually, there's a lot of work that's been done experimentally on on tipping points in nature and tipping points involving not only individual species, but the whole structure of the community. Some of my first ecological work was written with the great experimentalist Robert T-Pain in the intertidal region, and this provides some of the Northwest United States and this provides some of the best examples of sudden tipping of systems having removed the top predator from the system, what he called a keystone species.

In that case, it was a starfish which fed upon barnacles and mussels and other species. But that's not crucial for what I'm going to say. And he showed that the removal of that species called a qualitative change in the structure of that system. And one of his proteges, now distinguished ecologist named James Estes, who's at the University of California, Santa Cruz, took those ideas and apply them to what had happened with the hunting out of the sea otters front, most of the areas of California, so that the population was down into, well, less than 2000 there.

That caused an eruption of shellfish that the sea otters had been feeding on and the elimination of offshore kelp beds, which was highly destructive to fish populations. So this was a qualitative change and one of the most dramatic ones in an ecosystem and one with economic consequences. But there are lots of other examples since that time. For example, our work on Forest savanna systems in which fire is a driving element in semi-arid regions.

The work of Martin Schaeffer and Steve Carpenter on shallow lakes and of course the work that you mentioned, which is mainly the predictive of Tim Lenton and others on global circulation patterns. One researcher who was at the Stockholm Resilience Center together with me and two others, wrote a paper in Science a few years back on what we call cascading tipping points, in which we look both at climate indicators and climate tipping points and ecological tipping points not as independent elements, but as parts of networks of cascades that the flip of one could lead to the flips of others.

Just to give you a couple of examples. Fire in boreal forest could lead to Arctic warming, and that Arctic warming could lead to the weakening of the thermal healing circulation. Eutrophication patterns for example, the things that Carpenter discovered been studied leads to hypoxia, can lead to dead zones. And when that occurs in the ocean, this has impacts on coral reefs.

So we get a whole sequence of tipping points and they're all interconnected with each other. So going back to your original question, I don't view what's going on in the global circulation patterns in climate systems as different than what goes on in ecological systems. Mathematically, they're very similar phenomena, but practically they're integrated with each other.

Jason Mitchell

By the way, I do remember reading about the the finfish kelp and shellfish. I believe it was abalone.

Simon Levin

Actually, there are two main shellfish that are that involved. One of them is the abalone, which became an economically preferred item. But but the other thing that the otters fell on were species that feed upon the kelp. So sea urchins in particular by feeding on the sea urchins, the otters dramatically changed the structure of the system. The removal of the otters led to an explosion of the urchin population and denotation of the offshore kelp beds, which provide protection and nutrients for the fish populations.

So that's another dramatic chain of events.

Jason Mitchell

I guess. I'm just wondering what was the upshot in terms of the economic interests of this shellfish industry versus the finfish industry? Well, I.

Simon Levin

Think that's still an open question because, of course, otter populations became protected about 100 years that go with the Marine Mammal Protection Act, but otters were slow to recover, and so efforts were made to reintroduce them into various areas. And this led to a great deal of controversy, as you point out, between shell fishermen and fishermen. I don't follow that closely, but I don't think that's completely resolved.

Jason Mitchell

You mentioned Tim Lennon, and I remember reading in his paper many risky feedback loops amplifying the need for climate action. And in it there are a couple versions of it, one an earlier and one a later, where he sort of expands on the physical feedback loops. But then this latest one I found really interesting that he now includes 21 biological feedback loops for the first time.

Given the fact that the field of ecology has undergone just an incredible revolution over the last 50 years in approaches to experimentation, mathematical modeling, I guess I'm wondering how do you sort of see that arc of understanding around feedback loops and ecosystems evolving?

Simon Levin

First, Tim is a good friend and colleague and I think he's perhaps the most important person coming from the physical side towards the ecological side and trying to develop the interplay between scientists on both sides. So as you pointed out, the modeling is improving the incorporation of both positive and negative feedback loops, but there's a limitation to what one can expect to predict with complex models.

I think Tim's point is laying out look at all these ways that biological feedback loops and and physical feedback loops can can affect the dynamics of the system. But it's not ever going to be possible to take a system with 21 feedback loops, never mind 21 biological feedback loops. And on top of all of the physical feedback loops and develop a predictive models, what's going to happen?

We have to find ways to reduce the dimensionality of the system. The Einstein is famous for having said one should make models as simple as possible, but no simpler. But identifying all these feedback loops doesn't mean that we are done and that we've we've got a predictive model. I think it argues in many ways not only for dimensional reduction, but for the importance of experimentation, like the experiments of pain that I mentioned in the answer to your last question and the development of a precautionary principle in fisheries, there's a notion largely due to both Hollings group and Colin Clark and Donald Ludwig called adaptive probing, which means you'll never be able to understand the system

if you only observe it close to an equilibrium. You have to find ways to experiment with the system, whether it's physical experimentation like pain did or or in silico as many of us have done to try to understand how the system is going to behave away from equilibrium. We'll always be limited in our predictive capacity. Any high dimensional system.

Let me give you one other example that that may be clearer. If you and I are playing ball and I throw you a ball, what's going to happen in it affecting whether you catch that involves a whole bunch of feedback loops within your body, neurological feedback loop, muscular feedback loops, physiological feedback loops. But if I tried to predict whether you were going to catch the ball based on a model that tried to incorporate all those feedback loops, it would be hopeless.

I've got to find some way to do what so Anderson said and take into account that more is different and develop more macroscopic models at the higher level, just as economists do in moving from microeconomics to macroeconomics.

Jason Mitchell

One of the fascinating aspects for me doing this research, especially for for this episode, was trying to kind of understand the arc of your work. And that's a doozy. Over the last 50 years. It's extended from your roots in mathematics, physics and fluid mechanics to ecology, and then to the study of socio ecological systems, cooperation and the governance, the comments to take on complex systems problems.

It seems like the turn towards governance and policy is almost inevitable in some way for scientists in the environmental fields like climate change in ecology. So how do you think back on this expansion, was it organic when you reflect back, or does it reflect a larger frustration with the constraints of the science community to drive real world policy change?

Simon Levin

First of all, thank you. I have to modify what you said because this year is the 60th anniversary of my Ph.D. So it's actually going back actually goes back 60 years. And since your audience won't know what my path is, I started in math with a physics minor. My Ph.D. was in math, but I realized in graduate school that I really wanted to use it to address problems in biology.

And I went out to Berkeley to work with one of the distinguished fathers of Operations Research, George Danzig, who was interested in biology. But I was really interested in environmental problems. And this was about the time that Rachel Carson began publishing her work. And and my close colleague now, Paul Erlich, and his wife wrote their books about population growth and and the implications of that.

And so I moved to ecology and environmental problems, and I worked as a theoretical ecologist for about 20 years, but realized that this was not enough. Then if I wanted to. Going back to your first question, really, if I wanted to address environmental problems, I had to reach out to economists and social scientists and ultimately to politics and governance.

And I must say now in the last 12 years to the business community, because none of these disciplines by themselves could solve these problems. There were four organizations that were key in my development, and this moves to the to the answer to the question about the field as a whole. One of them was the Bayer Institute that I already mentioned.

The second was the Santa Fe Institute, which thought about complex systems across disciplines. A third was an organization called JOTZO, the International Institute for Applied Systems Analysis, which was set up also little more than 50 years ago in order to facilitate collaborations between at that time US and Soviet scientists. Ultimately, this extended to about 20 countries, a very important organization.

And finally, the Boston Consulting Group, with whom I've been working for the last 12 years to try to bring the business community in. And there is great concern. We'll probably get back to that issue later of concern in the business community about global change and biodiversity loss. I chaired the boards of the Bayer Institute and ACA and the Science Board of the Santa Fe Institute, an academic fellow at the Boston Consulting Group.

I'm not alone in this tradition. There were few of us 60 years ago, but there's been a convergence of people from multiple disciplines, and the organizations I just mentioned, they're examples. My lab is full of students and postdocs who come from physics and mathematics and engineering and want to address ecological problems, as well as ecologists who want to strengthen their mathematical approaches.

It's what Ed Wilson, the great biologist, talked about in one of his last books. Maybe it was his last book called Conciliate. It's what the National Science Foundation talks about when they talk about convergence. It's finding ways to bring together the disciplines from math and physics and biology and ecology and economics and social sciences and politics, and as you said, governance.

And so indeed, that's become the focus of my lab and increasingly of lots of the people I interact with.

Jason Mitchell

It's fascinating. It's also pretty clear that the political economist Lynn Ostrom, and her notions around poly centricity, common pooled resources and obviously public good seems to have made a pretty significant impact or imprint on your thinking. How do you see your work around complex adaptive systems, sort of coalescing with her work on complex economic systems? And how do you see it being applied to address global environmental problems?

Simon Levin

Right. Well, I so her work was on not just economic but economic and social systems. Lynne was a colleague and a collaborator. She was active in the Bayer Institute and in the Santa Fe Institute. I visited her workshop at Indiana twice, once the lecture once take part in a workshop, and she asked me to come and talk about complex adaptive systems.

As you probably know, two centuries ago, William Foster Lloyd introduced the notion of the Commons, and that was picked up by Garrett Harding about 60 years ago when he talked about the tragedy of the Commons. And Harding said that the solution to the tragedy of the Commons was mutual coercion, mutually agreed upon. But what he meant was largely that individuals would band together to develop governance systems that would regulate individual actions from the top down.

Lynne came about this from a different way. Her work on social norms and the emergence of institutions and collaborations, which are indeed central to my thinking, depended upon individuals in small societies banding together to develop social norms that ultimately became institutions that could governance actions. And so my first paper on social norms was actually before I knew Lynn's work was about 20 years ago, together with the mathematician Richard Direct, and the same year with one with Paul Ehrlich.

But it's been informed by Lynn's work and everybody in my lab with whom I work has been very, very influenced by her way of thinking about the emergence of social norms from the bottom up in evolutionary ecology. We've been interested in cooperation for a long time. The starting point is cooperation between genetically related individuals, in which it's quite easy to understand why individuals will do things in order to benefit others.

But one goes from there to what's called reciprocal altruism. You scratch my back if I'll scratch yours, and then two more indirect processes, what's called indirect altruism. Sometimes the great baseball player and manager, Yogi Berra, is quoted as saying, If you don't go to other people's funerals, they will come to yours. But to make sense of that, one has to understand if you don't go to other people's funerals, then then when you die, people won't come to yours.

And and then more generally, and I think we'll get to talk some more about this later to the emergence of cooperation, a collective intelligence, collective action, and how do we get there? And we spend time before moving onto governments, studying things like bird flocks and fish schools, why they become more organized, how they become organized, how they are held together, and a variety of other examples from biology in which cooperation and indeed social norms in my department when I first arrived was a man named John Tyler Bonner.

A great biologist, passed away five or six years ago who studied small organism called the cellular slime mold and talked a lot about social norms and the social cell he called it. So yes, Linde's influence on my work has been enormous.

Jason Mitchell

I remember reading her paper a Polycentric Approach for Coping with Climate change right when I was doing my master's, and she recognized in these free rider problems and global agreements and instead pushed for many different approaches at different, generally local levels in a way where there's this shared kind of responsibility. So what do you think she would say now about the complexity of biodiversity loss and now the free rider problem when it comes to maintenance and regulating services, these kinds of provisioning services that you talk about in your paper?

Simon Levin

Right. Well, when Lynne realized that these issues were important, she brilliantly went off to do a sabbatical with the Nobel laureate game theorist, the runner at Kelton, with whom I also collaborated. She clearly recognized that biodiversity loss was a problem similar to climate change, and so she had been right on board with the same sort of thinking. I did another podcast with Nick Siller, who had been the head of risk management at Prudential Insurance in the US.

In that podcast. It was focused on the parallels between dealing with climate change and dealing with pandemics, in this case COVID 19, and how all of these problems required a tradeoff between the libertarian urge in terms of individuals own interests and the collective goods, and indeed in many cases, the collective good feedback immediately to individuals. An example in a paper that I published led by my student Shady Side ROI, the issue that came up was what's called vaccine nationalism.

The notion that as we develop vaccines, we ought to prioritize our own nations and not worry about other nations. Well, setting aside even the moral issues, which I'm not proposing to do, that's a shortsighted policy, because if you don't deal with these problems in other countries, new variants will arise that will come back to affect us. And obviously that's true with biodiversity loss and climate change too, because of the global nature of the lot of the services we're talking about.

In Lyn's view, one has to take into account the fact that local factors are unique, that individuals will band together to maintain local processes. But then, as you say in her focus on policy centricity, a notion she developed with her husband, Vincent Ostrom One needs to use these local cooperative building blocks and find ways to expand cooperation in a hierarchical way to the global level.

Actually, I wrote a book which came out, I think, in 1999 or 2000. It's called Fragile Dominion Complexity at the Common and the Commons in which we I laid out these issues and the notion that, you know what, NIMBY is perhaps not in my backyard, that people are most concerned about issues that are close to home, and it becomes harder and harder to extend that interest to the global level.

And this was Lynn's focus when she talked about Polly Centricity build on the concern for the local environment and use that as building blocks to global cooperation.

Jason Mitchell

It's interesting. I mean, what do you think the lessons are from all the climate action and even sort of the work, as you mentioned, put in through COVID that can be carried over to address biodiversity loss? How can different groups and disciplines work towards collective solutions when today's political polarization feels like kind of moving backwards a little bit?

You know, what does it say about the notion of true sociology and society's willingness to commit to intergenerational future transfers when the political climate doesn't seem to support so much?

Simon Levin

Yeah, well, I find that one of the most depressing aspects of our society. Kentaro and I wrote a paper on intergenerational transfer of resources. Now about 15 years ago, and, and we continue to work. I continue to work on these issues. I've been very concerned about the dynamics of political polarization. In fact, organize a set of meetings and edited a special issue of the Proceedings of the National Academy of Sciences on this, in which we had papers from in each case that were collaborations between complex systems theorists and political scientists.

And first of all, in those papers, it's made clear that there are two kinds of polarization. One is an issue based polarization, which I think is very healthy, in which people disagree on their attitudes towards the issue. We can argue them out. And the other is what's called in the political polarization literature, effective polarization, which means you begin to dislike and find ways to bring down anybody who's got the opposite point of view these feet on each other and create a polarization, which is a dimensional reduction in the system, which, as you point out, makes it extremely hard to develop collaborative solutions.

James Madison, who was one of the authors of the Constitution, brilliantly solve problems that polarization would bring to its new democratic republic, and in particular that the existence of political parties would lead to this effect of polarization. I don't think anybody on either side of the issue or in the middle would argue that we're not seeing that today.

Madison was right about that. He felt it was important to design a system that would avoid that. Unfortunately, they fail to do that because we have a highly polarized system. Now, one of the papers in the special issue that was led by my colleague Karina Targets and our joint student Morikawa Katsu, looks at Madison's dream and why it failed.

And building on that, Anne-Marie Slaughter, a leading political theorist, and I Emery, is the head of something called the New America Foundation, are organizing a set of meetings. We've already had one on Internet, and the next one is due up at the end of this month on Revising Institute tions for achieving international regulation of a variety of issues.

We're going to run one on climate change, and the first one it's coming up is actually on artificial intelligence. The idea of pro sociology is an idea that has roots in evolutionary theory, going back to Charles Darwin and altruism and issues of that sort. But why do we have both sociality, which means, by the way, caring about others, especially others who are not related to you is an extremely important influence.

A higher degree of prosocial reality. The caring about others, the more likely obviously we are to achieve international cooperation or cooperation at any level. And my colleague, The Economist, I want our sticks in and I have been exploring this in a variety of systems. But it also begs the question of why is there pro sociology? How is that arisen?

Caring for others? And this is an idea explored the first paper I know on it that really looks at this from a serious point of view is the late economist Herbert Quintus. But there've been a variety of other papers and Dixon and I wrote a paper a few years ago demonstrating how prosocial reality would arise. And this the short answer to how pro sociology arises is it's easy to show that everyone's better off in a pro-social world.

The question is, how do you get there? Well, if I want my children to be in a pro-social world, I might be willing to make an investment. And that's what we show, for example, in education systems and the like, which will increase the likelihood they'll be in pro-social world. So that's how we think this has arisen. And of course the discount rate now, which I've mentioned several times comes into this, but I agree with you, the current trends are depressing.

I'm not confident that we can break out of it, at least not in my lifetime. But I think we have to try and whatever side of the political spectrum you're on, I think one would argue that we need more cooperation and more attention to the compromise in the interests of others.

Jason Mitchell

I want to change lanes, move back to the business side for a second. It seems like there's a clear gap in both data and methodology between the scientific community and the investment community in understanding nature related risks, investors have tended to focus on biodiversity loss using metrics like MSA mean species abundance generally with an emphasis on charismatic animals and often ignoring fundamental elements like microscopic biodiversity.

By contrast, the science community who of course look at biodiversity but also pay very close attention to ecosystems and their ability to provide ecosystem services. But I find that they tend to use metrics like the by the Biodiversity Intact Tackiness index. How do you see reconciling all these different approaches, each that focus on footprint or dependencies or proximity and geospatial impacts?

Simon Levin

Yeah, So I'd say it's largely an educational issue. It isn't Conservation groups and when you see the advertisements on television, they focus on elephants, lions, giraffes, you know, the charismatic species. It's messaging and it's it's useful. But if you start talking to a general audience about the need to preserve micro-organisms in the environment like rice opium, which is responsible to large extent for things like nitrogen fixation, it's not going to have the same ring.

And I think that message is the one that the business community hears because these are the things they think, well, these are the things that people care about. People don't care about rice, opium, even though they should. We have to get across the sense of regulating and maintaining services and the loss of ecosystem functions. Peter Corriveau, who was a student of mine and I edited a volume some years ago actually in honor of Robert Payne.

We called it the importance of Species, and it asked the critical question, which is aren't all species equally important? An argument would be that they're not, and that's not something that necessarily would sit well with a lot of my conservation biology colleagues who value every species the same. I have a separate argument for them. Why? I think that that's not the right way to go.

But when one's writing environmental legislation, it's very difficult to write it in any other way than to protect things that the species level or indeed at the population level. But for example, the American chestnut disappeared largely from the forests in the Northeast. U.S. had very little impact on the ecosystem. It's a loss and I'm sorry to see that species go, but species come and go, Paine emphasized.

And as this and others, keystone species, species whose removal will cause the collapse of the population, and I think people in the business community are starting to appreciate the broader issues. And that's why I'm spending a lot of my time working, for example, with the Boston Consulting Group and with Nick Cilic, whom I mentioned. Nick and I did this podcast together.

Nick, by being in the insurance industry, recognized a lot of the problems which were going to come down and affect the insurance industry on a very short 10 to 20 year time scale. But even that timescale was long compared to what many of his colleagues were interested in. So we've been working together to try to get across the message and that's why Arrow and Gupta and our colleagues have been developing these notions of natural capital.

There's a very active natural capital project that base at Stanford and led by Gretchen Daly, who also has been very involved with the Bayer Institute, to try to emphasize the importance of understanding things that go beyond the big megafauna and the beautiful species to look at and in particular at the microbial communities and things of that sort which support all the services that we depend upon.

Jason Mitchell

What role do you see markets playing with respect to nature, and why do you think biodiversity loss has been neglected so much relative to climate by investors? Obviously, it's starting to change obviously with the launch of TFT, but it's still pales in comparison, which is strange given some of the data that's been out there. For instance, in 2023, Bloomberg estimated that global gross GDP could be 30% lower, given impacts to biodiversity.

So the materiality is is clearly there. Why do you think the economics of nature or ascribing any kind of value to biodiversity is such a difficult exercise? And I think as an add on, what are your thoughts about the linkage between nature and financial markets? There are clearly some mixed views about the financialization of nature.

Simon Levin

Yeah, there are a number of issues there. It's overall an education problem. And as you mentioned at the end, there are some things that you can monetize easily because there are markets for them. There are other things for which there are no markets. And thus group that I talk about this in our paper, but it's very difficult to put a price in.

It's not clear that people, I should say, push back against the notion of putting a dollar value on nature. And one of the reasons for the pushback is the notion you put a dollar value and then somebody comes up with a technological fix, making those elements of biodiversity less important and everybody says, What's the problem? So so there is a danger in that.

One of the things that which you're probably aware is that recently it was estimated that now more than 50% of the people in the world live in cities. Certainly the number of people living in cities is increasing. All those people are experiencing the extremes of climate change. All those people are aware of the forest fires, either because they read about it in the papers or because they see the smoke and affects the air quality where they live.

Many of those people directly experience floods and issues and other extremes of weather. But as they move into the city, they're not noticing that biodiversity is going down. They don't see the impacts of biodiversity and they don't understand fact that we're dependent upon them going to try and get people to eat healthy diets. That's already a difficult thing, not only because of the temptations, but because there so many indirect pathways.

So I think in the case of climate change, there is such a short term direct impact on people that they are sick. And nonetheless, of course, you're you're aware that not everybody buys into climate change, even now. Reminds me of the movie Dollar Cop in which people deny what may be obvious to them. So we've got an education problem.

We've got to we've got to build on climate change and point out to people what the risks are to them of loss of biodiversity and other related issues like the increasing likelihood of pandemics and the like. We've got to change social norms. As I mentioned earlier, markets by themselves are not going to address this unless we can find ways to close them up in a functional sense because they don't adequately take into account the externalities, the social costs, and certainly not the long term effects.

Things are going to happen ten or 20 years down the line. Most people don't care much about the future. 20 years ago, never mind 100 years from now.

Jason Mitchell

Yeah. Let's let's talk about those discount rates. How do you see investors thinking about discount rates in the context of nature if you've had those discussions? And for me, I'm thinking back to a recent report titled The Emperor's New Climate Scenarios, which was published in the UK and makes a case that investors essentially underestimate the economic impacts of climate change.

And the counterargument to that is that investors are discount rate driven so that the impacts of climate and presumably ecological impacts, biodiversity loss to investment portfolios tend to get muted over long horizon periods of 30 5000 years by virtue of discount rates.

Simon Levin

Absolutely. So three or four points to make on that. First of all, you mentioned the UK. There was a report that came out for the British government some years ago led by distinguished economist Nick Stern, talking about the climate change and what we should do about it. And indeed in that as well as in the work of leading economists who are working on climate change, the issue of what it's worth to do something about it depends upon what discount rate you use.

Stern used something between one and 2%. There's a lot of debate about what one ought to use. There's an argument to be made for a zero discount rate in that if you want to leave for the future, the same options that we have and you basically shouldn't discount their value at all. In fact, if you believe that population size is going to continue to increase for a while, up to 9 billion, maybe we need to leave more to them, which means a negative discount rate, really.

Marty Weitzman, another great economist who passed away a while ago, did a survey of economists about what discount rate should be used in thinking about the future. And he got a wide spectrum. And what are the implications of having a wide spectrum as if you average those together? And I'll say in a bit why one might want to average them together.

One gets something which no longer looks like a exponential discount curve, but is what's called hyperbolic. Or he called gamma, which means it's much steeper initially and then levels off the societies are making decisions. And so that's the argument. It's going to do things democratically for averaging together the interests of everyone. And so, for example, I would argue that CEOs and politicians have very steep discount rates because they have to produce results on short timescales.

Other people have different different account rates and in fact, our discount rates vary during the day and depending on the circumstances, depending on the region of the brain that's dominant. And so we actually discount hyperbolically and and so do other animals. And this has been shown in experiments. It leads to hyperbolic discounting. So when I for example, when I get up in the morning, I say, okay, at dinner tonight, I'm just going to avoid dessert because I know it's not good for me.

But then dinner comes and I think, what the heck, I've been doing it every day up till now. I'll start that diet tomorrow. And that puts me and the evening in conflict with me in the morning. And it's because I'm using a steeper discount rate for the short term in the evening than I did in the morning.

I'm being controlled by different regions of the brain, I think. And so the issue of discounting and discount rates is fundamental to doing things about the environment and the right way to take that into account, I think is something that requires a lot of our attention.

Jason Mitchell

I want to finish off with one last question. It's a widely acknowledged controversial idea, but where do you stand around the notion of Gaia relative to all your work? James Lovelock's Gaia hypothesis is essentially about regulating and maintaining stability in the complex adaptive system of the earth. Lovelock even describes the workings of Gaia and almost biological language with terms like Superorganism and geo physiology, but that obviously centers on Gaia adjusting to think problematically to human needs.

Is this a basis that we can build on? I know that obviously Tim Lenton is sort of trying to advance it under Gaia to data. Where do you stand.

Simon Levin

At what Tim said a lot to resolve the issues here. He was a student of Lovelock's. I think the earlier arguments of Lovelock that we live in, as we want to call it, a superorganism, so it's important to preserve the biosphere and that makes sense. But the view of the biosphere is a super organism shaped by evolution that would adjust to preserve.

This does not make sense to me and is dangerous because it presumes that the biosphere will self-correct. I think that there was a series of books. The first one is the one I will single out by Steve Schneider and Boston on Different science views on Gaia. And there's a paper in there by Robert Kirshner about the evolution of the concept of Gaia.

So I think initially it was a useful idea, and Kim has worked hard in order to help us to understand how some sort of macroscopic regulation could emerge from local self-interest. But he well realizes that that's no guarantee. And in fact, we are in some ways committing evolutionary suicide through our actions. We are overwhelmed, meaning the biosphere and Gaia has no hope of doing on its own.

We have to modify our behaviors. So I spent the first part of my career doing evolutionary ecology. Evolutionary ecology is based on understanding how organisms with particular properties leave offspring in. If they if those offspring have the better properties, they will come to displace the others. But with the biosphere, we've only got one. It's not producing little baby biospheres and we're going to select the best of those.

We've got to preserve the one we have. So I think one has to be extremely careful about the notion of Gaia while preserving the notion that the biosphere is all we've got and it's something that we have to understand as an emergent super thing, and it's only through our actions that we can preserve it.

Jason Mitchell

That is a fantastic way to finish. So it's been fascinating to discuss what's at stake when we talk about biodiversity loss, how your work is expanded into the sociological, political economy and policy space, and why a common language, a grammar for economic reasoning, as your paper calls it, is vital for bringing together different disciplines to understand nature. So I'd like to really thank you for your time and insights.

I'm Jason Mitchell, head of Responsible Investment Research at Mann Group here today with Professor Simon Levin, James s McDonnell, Distinguished University Professor in Ecology and Evolutionary Biology at Princeton University, and the director of the Center for Bio Complexity in the High Meadows Environmental Institute. Many thanks for joining us on a sustainable future and I hope you'll join us on our next podcast episode.