Disappearing Species

for years. She's a staff writer at The New Yorker and the author of the twenty fifteen Pulitzer Prize winning book The Sixth Extinction, which is all about biodiversity loss as a result of the human impact on the environment. Elizabeth, thank you very much for being here with us. I want to ask you about biodiversity from a range of perspectives, and I want to start with the question of what

biodiversity is. It's a kind of catchy phrase, and we all feel bad when we hear that biodiversity is endangered. But what do we mean when we actually say biodiversity. Well, that's a good question. I think that in its most basic sense, you know, biodiversity refers to the variety of life on Earth, and a sort of shorthand is often how many species there are on Earth, and the fact of the matter is, we don't know how many species

there are on Earth. They like to use that estimated number of eight million, right, Yeah, I mean there are all sorts of numbers that get thrown around because you know, we've only sort of named and identified, you know, around a million species, so people have to sort of extrapolate from that based on, you know, the rate at which you're discovering new species. Things like that. We do know, don't we that? However, many species there are a whole

bunch of them are insects. Right. When people is that eight million number, they tend to say five and a half million or insects. And even if you accept that as a total projection, they're saying that substantially more than half of the species in our biodiversity measure are in fact insects. Yes, the vast majority of species on Earth are invertebrates, so you know, animals without a backbone, and

of those, the biggest group are insects. Yes, definitely. So when we talk about the number of species on Earth, no matter what it is, as you point out, or even what order of magnitude it is, it's likely that you know, a great, great proportion of that will be insects. So can I ask a follow on question? That's it's a little philistinish, I fear, but I actually think it,

So I want to ask you about it. And it's this, when we're talking about these vast numbers and then we talk about decline, what is the thing that we're supposed to be so panicked about, right, if we were to go from eight million species and I understand it's not a real number to seven million species, what is it it's inherently so worrisome about that observation on its own. Well, I think there are a number of different ways to

answer that question. And the first one that comes to mind is if you're eliminating you know, a million species, that's an indicator that something very very serious is going on. And if you're a living organism, you know, like a human, you might wonder, you know, why, why is that happening? And how is it going to impact you know, my species, because it's pretty unlikely that you're getting rid of, let's just say, even an eighth of the species on Earth

with no impacts. Now, if you want to look at it, you know, kind of what does this mean to me? What are those million species mean to me? Right now? I think the answer that you could give is you just don't know. You know, human life, though we live in this sort of a lot of manufactured habitat most of us, most of the time, we're still absolutely vitally dependent on the biological world, biological geochemical cycles, which we're screwing around with very very dramatically right now, and that's

why we're seeing these very high extinction rates. And which species we actually depend on, which species are absolutely crucial to human life, we don't know, But you wouldn't want to screw around with it to the point that you find out and realize, oh, that that was the one that was really crucial. So can I follow on that too? Though? I hear the argument and it sounds like it's an argument from uncertainty, right It says something like, that's a

lot of species. Anytime you're losing a high percentage of what's out there in the world, things could go terribly awry, and we just don't know how that might be the case. So you know, why not try to mitigate and avoid the things that are causing this decline in species? If that's the argument I tell me first time, I getting it right. Well, I mean that's I could offer you another argument, and that would simply be an ethical argument. I suppose what gives humans, you know, we obviously have

the ability to eliminate a lot of species. What gives us the right, as it were, to do that. I'd like to talk about both of those, if it's if it's okay with you. They both seem super important. The first is a kind of human centric argument, right, you know, we should care about these features of our world because

we might really be in trouble if we don't. The second is an argument from morality or from ethics, not humans focused in the same way that says, well, you know, we shouldn't assume that just because we're the humans, we have the right to do all these things that we have the capacity to. So I think those are both

super interesting and important. I'd love to talk about both them. Yeah, on the uncertainty argument, this seems to me kind of different than the argument with respect to say, climate change, which is, you know, the other very pressing environmental issue of our moment. There there's overwhelming evidence that rising temperatures are going to transformative and transformatively bad effects on huge numbers of human beings in the pretty near foreseeable future.

And that sounds like, as you know, you're looking for clarion calls to action. That sounds like a pretty powerful one. It's human focused, and it says things are getting bad in the following set of ways with respect to the biodiversity. Isn't the uncertainty argument slightly mitigated by the history of big extinctions? I mean, you call your book the six Extinction, because there are five massive prior extinctions, and those all took place, and they were caused by disasters into typically

of various kinds. Of course, they led to big changes in the nature of the biodiversity that was out there, but we don't know for sure that we would be

the dinosaurs as it were, right, I mean. And the question then becomes, if we're balancing at the human level a whole bunch of competing interests, the main one, as far as I can make out, is the size of a population, because the report suggests that the most significant of the various things that's leading to the decline and biodiversity is just how many people we have and growing food for them and eating animals and fishing for fish, and the range of other features that come with having

so many people. So if we're trading off human values like the population against uncertainty, isn't that sort of different than the climate change context, where you know that we're in a lot of trouble, and we're in a lot of trouble very very soon. Well, I want to see if you if you accept the idea, you know that we're causing a mass extinction, a spasm of extinction, you know, potentially on the level of these mass extinctions of the path the most recent one of which you know, it's

believed was caused by an asteroid impact. That's the event, the End Cretaceous extinction, which did in you know, not just the dinosaurs, which were a dominant form of life on land, but also lots of other major groups of organisms, and also opened the door for us, not totally coincidentially,

our little rabbit like rodent like ancestors. Yes, absolutely, But even if you were a bird or a small mammal, kind of shrew like mammal which lived through the End Cretaceous extinction and eventually did give rise to us, I don't think that the End Cretaceous extinction was an event you would have wanted to live through. It's not the kind of world you would have wanted to, you know,

bequeath to your shrew like children. I think that the defining characteristic of a mass extinction is a lot of a lot of bad shit going down and cascading effects that would affect all groups. So yes, some made it through, absolutely, But to take the kind of view sixty six million years later, it's easy to sort of sort of blithely say, well, you know, that doesn't look so bad from a distance of sixty six million years, But I think I look bad.

That's that's not the argument, But go on, okay, But also to say, well, you know it takes your you know, you pay your money, you take your chances. We're the dominant organism. Now we might come through this extinction event still of the dominant organism. I don't think any biologist on the planet would say that would be a good debt to make. But that's not I mean, to be completely you know candid, that's not that I don't think

is the strongest version of the argument. I mean, the strongest version of the argument is something like this, we're involved in a world of constant trade offs. We have a lot of people on the earth. Those people need to eat, and even if all they're eating is fruits and vegetables, they need agricultural in order to do that. If we significantly changed the degree to which we're relying on agriculture and other things to raise food, if we could do that in some way, they would still let

us affordably feed all these people that we have. That would be one thing. But we don't actually have the full capacity to do that yet. Well that's a that's a hardy I mean, you could say you're damned if you do, you're damned if you don't. I mean, we rely very, very heavily on you know, the health of our soils, pollination services that are delivered for free by lots of those insects that we were talking about. It's not clear that you can do without those and feed

you know, eight billion, going on nine billion people. Totally fair point, but it's a tradeoff situation. You know, reducing population substantially, which was the view of all thoughtful educated people a century ago. We don't think that's ethical anymore. You know, we're beyond that kind of eugenics phase. We we accept the world's population for what it is, and so then we're in a world of trade offs and how do how do we make those trade offs against uncertainty.

The extinction of the Cretasius tertiary boundary that we were talking about was an asteroidal extinction. It wasn't human caused. This one is human caused, and to some extent, it's the result of humans making decisions that are designed to serve the interest of humans. They may be the wrong decisions, we may be getting it totally wrong, but they are decisions, for example, with respect to growing things that humans have

made the judgment are necessary to keep us going. You're trading off, on the one hand, supporting human life against on the other hand, the uncertainty of the consequences of the decline. Yeah, and I think that is exactly what we're doing. We're doing it unconsciously, and I also want to say we are quite possibly doing it very unwisely. What looks like a good trade off in the moment right in twenty nineteen, which looks like a good trade off to us right now, is that a good trade

off for our kids? Is that a good trade off for our kids kids? I mean, these are questions that you know, unfortunately from purely scientific, biological and even you know, probably ethical view are unanswerable, but I think they have to be factored in. One other point that I want to make, and I think it's pretty important, is as we eat higher and higher, and as more and more of us, you know, eat higher and higher, as it were, on the food chain, we're using more and more calories

to produce our own chloric intake. So I don't think it's at all true that you know, land use decisions are straightforward. They're very very complicated, and they you know, have to do with not just feeding eight billion people, but how we're feeding eight billion people. For sure. I don't dispute that for a moment. I wanted to turn out to this ethical argument that you raise, which is different from the where you know, we're playing dice with

our future. It's the argument that, as you put it, humans have the capacity to have a you know, an unpresented effect on the environment. That's why you know, a lot of people think we're already in the anthropasy and age defined geologically as the time that humans are having an impact on the earth. But we shouldn't. We don't have as you put it, the right to do that. I don't know if you hold that view, but I'm actually really curious to hear whether you do, and if so,

to hear a little bit more about why you think that. Well. I mean, I think from a obviously, humans are one species out of let's just say eight million, right, I think, you know, the history of human consciousness, as it were, has been a kind of widening circle of our concern and I think that, you know, we may look back at this particular moment when we kind of blithely did in a lot of species, and a lot of species I want to say that are very very close relatives

of ours. I mean, you know, orangutangs, gorillas, chimps are all very highly threatened right now. So we are doing in you know, species, a very high level of consciousness.

We can you know, you can get into the question of also, you know, whether we make a distinction, whether this ethical argument even allows for a distinction between conscious creatures and unconscious creatures, And perhaps it doesn't, but I should point out that we are sort of doing in you know, our evolutionarily our very closest relatives, and I don't think we're going to look back on this. I don't think that, you know, humanity, whatever you know becomes

of us, is going to look back at that. That's going to look like a crime. That's going to look you know, not less necessarily crimes against humanity, but crimes against humanity's closest relatives. I'm super fascinated by this line

of line of thought. I always have been, and it's you know, a lot of environmentalism takes some part in this kind of mode of thinking that we ought not to have this effect on the world, not just because we're causing pain, not just because we're eventually having you know, terrible effects, as you said, killing off our closest cousins, but more broadly, that somehow we shouldn't be so focused on human consciousness. And I guess my question, and this

is something I've always struggled with myself. So it's not like I think there's some magic blood answer to it is, what about the our observation that, although of course we do image far out of proportion to all other species, that no other species seems to exercise this kind of concern for making sure that they take into account the interests of other species, or even other individuals of the species I mean all species. But that just seems like

another kind of you know, human sallipsism. To be honest, I mean, this is meant to say that what would be salapsistic would be assuming that because humans uniquely have the ability to think of the interests of others, therefore it must be that the correct ethical way to be is I think of the interests of others. This is the question from meant to be from the other side, well, I mean, yeah, that's one way to look at it.

But I think that once again, the history of you know, the last you know, five hundred years or whatever from you know, turning from a geocentric to a heliocentric world should be sort of questioning trying to decenter humans. And we are faced with this really interesting situation and board knows, you know, if I had the answer to this, I would be happy to impart it. I don't, but I certainly think that all of these things are worth questioning

pretty profoundly at this particular moment in time. And so we're faced with this really interesting two divergent trends as that were here. One this as I say, d centering of people, you know, we're descended from a common ancestor with chimps. The Sun does not revolve around the Earth. There's revolves around the Sun. So we're one planet among you know, millions and potentially billions, So we're pretty small

aspects in the universe as it were. But then we're also one of the lessons of the last generation or so has been Wow, we are having a really significant impact on this one planet that we as humans call home and on everything that shares it with us, and that shares an evolutionary history with us that you know, we now know goes back almost four billion years. So

those are pretty heavy numbers in both directions. They sort of point and conflict directions, and the fact that we have not found as satisfactory way of working our way through them is unfortunate because this damage is permanent. You know, when you get rid of the species you have, you have permanently cut off its evolutionary possibility. So we're really screwing with the evolution of life. And once again, this goes way beyond you know, our kids and our kids kids.

It goes to the future of all life on Earth, you know, forever. I love the way you put that that there's a deep contradiction between two two different insights, one that we're just another species and the other that, boy, we're not just another species. We're having this disproportionate impact when it comes to screwing with evolution. To use your phrase, um, are you a believer that that's always a bad thing?

I mean, I assume that you're in favor of all kinds of ways that we tweak evolution that make us better off as as humans, from you know, from antibiotics on down. You know, I'm not I don't want to say, like, you know, screwing with evolution is some you know, you're right as you say, every time you know, you um, you know, step on that you know, aunt or whatever you've on some level, obviously everything is always you know,

screwing with you know, other organisms all the time. But I think we very rarely knowingly and consciously and happily cut off entire limbs of the evolutionary tree. And that sort of brings me back to our closest relatives. I mean, there were a lot of human cousins around at one point. We know more and more about different you know, sort of human species or subspecies. The Neanderthals, the nencipents, their doubtless others out there that no longer exist, quite probably

because of us. And we are also looking at getting rid of great apes. If you just look at the future of the evolution of consciousness, right, if we consider those to be the animals of the highest you know, consciousness, we are potentially creating a world where consciousness you know, will not arise again, or will not arise for a very very very long time, and you know, take a very very different form, quite likely at that point. But

it just so I understand. Are you saying that if those other higher primates continue to exist in and in larger numbers, that there would be the possibility of the of a repeat in the evolutionary process in which consciousness, at least of the human type it would evolve another time, another time around. No, I'm not necessarily saying that, although

that is that is certainly possible. I'm just saying that if you consider you know, our great ape you know cousins to be conscious, and I certainly think that most you know, animal behaviorists would that consciousness itself would continue to exist. There would be other species of apes that would eventually arise they would not necessarily be humans. They would be other things. They would be you know, they wouldn't necessarily be have any more or less consciousness, you

know than a gorilla does. Now let's just say, but um, that would be a possibility, that would bevolutionary possibility that was open. If you do away with all the species of great apes, as we are, you know, pretty much on our way to doing right now, then you're just

cutting off that evolutionary possibility. And I'm simply using this example once again of apes because I think that it, you know, there are a lot of other evolutionary branches that are being you know, cut off for a whole genus, let's us say, is disappearing, or there's only one species

left in the genus and it's disappearing. I mentioned apes because I think people have an emotional reaction to them, and if they thought of a world without great apes, and they think of that evolutionary possibility being closed off, that would have some you know, emotional connection that you know, if I tell you about this, you know, genus of I was just out in Nevada, and I you know,

was met saw. I don't know what word you'd use encountered a you know, a fish that's the last fish in its genus because we've been soaking the wall are out of the Nevada Desert, so all the other species in this genus are gone. I don't think that has as much, you know, kind of connection to people, but it's it's another way in which you know, we are we are cutting off that evolutionary possibility. Can I ask

about what we can do? I mean, what are the real world doable things that could substantially reduce the harm that we're doing to to biodiversity that's out there in the world. Well, I think that, you know, the basic answer, probably the first order answer would be gets back to that question of land use that we were discussing. I mean, if we did not cut down the rest of the Amazon, cut down the rest of the rainforest in the Congo, you know, these big big still extant and you know,

relatively intact what are called biodiversity hot spots. The tropics is where most of the diversity of the world exists. There's you know, historical reasons for that. The tropics have been have had a fairly stable climate for a long time and had the ice ages and the temperature, fluctulating, all things which are bad for a species continuation. Right There's just been a long history of life evolving under relatively stable conditions in that you know, that's one theory,

and it's it's a pretty popular theory. That's why, that's why there's so much biodiversity in the tropics right now as opposed to in temperate zones like you know, where you and I live, where you know, there was ice covering this area for you know, until twelve thousand years ago or so. So obviously everything that's repopulated where I live in western mass has has arrived re arrived in

the last twelve thousand years. So if we you know, sort of got together as as it were, and decided, okay, let's let's leave those parts of the world as intact as possible, that would be one way to really probably make a pretty big difference, not to stop this losses by any stretch of the imagination, because there's all sorts of other factors at work, including climate change, which that report which you alluded to, you know, talked about becoming

a major driver of extinction. It probably is not yet a major driver extinction, but it's it's it's looming very, very large. So another you know, point that I guess I would make getting back to this question of you know, climate change is something we can all see as a threat to you know, life as we know it for humans.

A lot of the things that we would try to do for our own good would also probably although not necessarily, because there are ways to combat climate change that would have very you know, very significant land use change component that would probably not be good for other species but might be good for people. So that's another potential trade off there. But it's also possible that there are ways to mitigate climate change that would have a big impact on the rest of the species of the planet too.

So there are there is in some senses, we're not pitting our interests against those other species, but we actually have a confluence of interest there. Elizabeth, you said something that really grabbed me when you said that if we could protect these tropical biodiversity hotspots, and you mentioned the Amazon rainforest and the rainforest in the Congo, that we would go some significant way towards reducing our attack on biodiversity.

And I have to say, you know, just by thinking about this issue a little bit and reading your book.

I don't think I sufficiently took on board until you just said it that in a way, this all may be more doable, or much of this may be more doable than we tend to think when we face major environmental challenges, in the sense that, although they are obviously very strong practical, logistical, and political challenges associated with reconfiguring institutions to protect indigenous people, who often are the people who live in these biodiversity hotspot zones, Nevertheless, if you

could achieve a lot of this by protecting a handful of identifiable areas on Earth, that seems a lot more doable than sort of a global transformation in either population numbers or in the way that food is grown, or even in human diet. I mean, there may be lots of great reasons to all of those things, and I don't dispute that, but when I think about the biodiversity challenge, when you're read the UN report, or at least it's it's summary, it sounds as though, oh, my goodness, you

know this is happening, It's inevitable. There's nothing that we could really do substantially about it that would actually be doable. But this seems a little more doable. This seems within the realm of the reasonable, and it also seems like it could be done without imposing tremendous costs on the rest of the world. Is that slightly more optimistic? Take that I just took away from what you said at

all credible? Or do you actually feel the pessimism that I previously felt and that I think I took away from your book, If you'll forgive you saying so, well, I guess I however, somewhere between the two, I mean. Ed Wilson has a fairly recent book called A Half Earth where he sort of proposes putting aside, you know, half of the land on Earth for for other species.

And that sounds, you know, like an awful lot. But you know, when you look at these pretty intact places like the boreal forest of Canada, the Amazon, the tropical rainforest in parts of Africa, you could you could imagine it. I think you can imagine, as you say, doing that now that requires us to think totally differently about the world's It requires, you know, transnational agreements. Unfortunately, you know,

there's no body and in fact, they very awkwardly acronymed ipb. Yes, was you know sort of designed to be the inner Governmental Panel on Climate change for biodiversity, to have some group that was looking at this from an international perspective. Now, do they have any clout? You know, that's a very very good question. Well, is there any talk of an international treaty regime, for example, comparable to or connected to the climate change treaty regime, which, you know, it's a

topic for another day. Of course, the great challenges that even that treaty regime faces. But is there any movement out there for a kind of treaty regime that would say, look, yes, substantial wealth transferred to the countries that house these biodiversity hotspots in exchange for much stricter protection of those zones with international monitoring if necessary, and guarantees not to turn that or allow that land to be turned into farmland, and again paid for. I mean, this would be more

expensive for the local people. And I'm the last person to want an arrangement to disadvantages the local people. And says that, well, because biodiversity hotspots are where you live, you have to continue to live in poverty. That seemed to me personally at least, exactly the wrong way to

go about it. But you can imagine a relatively as these things go, straightforward treaty arrangement where the rest of the world pays and gives advantages to the countries that are the hosts of the hotspots and they make certain commitments. Is anybody talking about that? I mean, it seems logical in light of what you've said. Well, there there is a companion treaty to the Framework Convention on Climate Change. It's the Convention on Biological Diversity. It doesn't get nearly

as much pressed, but it does exist. Admit, I've never heard of it until this moment, so you're right, it doesn't. So go on, and what does it say? You know, it is one of these very it has very high aspirations for how we're going to you know, preserve biological diversity, but it has, you know, no teeth. I think it would be a platform that you could work out international transfers of wealth, as you say, but I as far

as I know, those are not happening now. One way in which that is happening is with you know, these sort of forest credits that people are using as in connection with you know, climate change, right as offsets climate offsets. If you if you don't cut down your rainforest, you know will pay you, and that kind of sort of counts as a climate change mitigation effort. So that is one arena, you know, where where there is money changing hands, probably not a great deal of money, but a certain

amount of money changing hands. I want to sort of just close by asking if you see there being some spots for hopefulness. If you don't, that's that's totally fair. Um I you know, I'm reacting to the possible moves of treaty and regulation because if you can identify a handful of big bad actors, it's humanly possible to pressure them. I'm not saying it always works, but it's always at least there's a path forward that you can imagine, you know, following.

You can name and shame, you can put pressure, you can try to produce a regulatory regime, and those you know, again they're no guarantees, but they seems a little hopeful. But are there other points that you would think of, as you know, gee, looks like a way forward, This

looks like a possible success or a replicable success. Well, I think in theory there are, but all of the problems that we're looking at environmental problems cannot be solved without some kind of international framework, or cannot not even solved. I'm not even talking about solving them, cannot be mitigated without some kind of you very very serious international cooperation and as you suggest, probably transfer of technology, transfer of wealth. But we are not willing to do that right now,

and we are moving in exactly the opposite direction. We have a moment of resurgent nationalism when when we look back at this, at this moment which I unfortunately believe will be looked at as a moment of just extraordinary heedlessness and madness and consigning you know, future generations to some pretty bad stuff that we didn't have to consign them to had we gotten our act together earlier or

right now. I think that the fact that we are seeing this resurgent nationalism at a moment when international corporation you know, really couldn't be more pressing. Will that be looked at as a coincidence or will that be looked at as you know, part of this this human package of not being willing to face up to the facts

until it's you know, screamingly too late. Well, we humans are better at collective action than any other species, and we can do a lot more with it, and we can do a lot more bad things with our collective action any other species. And so we're sort of we're our distinctive features as a species are are definitely at the heart of the challenge we faced a biodiversity. Thank you so much, thanks for having me. Elizabeth Colbert offers us an extremely cogent and extremely depressing account of our

current moment. The problems we face are clearly international, and if we want to avoid massive extinctions, they demand solutions. It's not like we don't have the technology of international governance available. We know what that technology is. It's called treaties. It's called trees with teeth that can actually be enforced

and that will make governments preserve the environment. Unfortunately, we are also in a moment of profound skepticism via nationalism, of exactly the kind of international cooperation that would be necessary if we were actually going to take on the problem of the collapse of biodiversity. What comes next, I guess, is nothing good unless we're able to turn things around and begin to re examine the tools that actually let governments compel each other to do things to preserve the environment.

Deep Background is brought to you by Pushkin Industries. Our producer is Lydia Jean Coott, with engineering by Jason Gambrell and Jason Rostkowski. Our showrunner is Sophie mckibbon. Our theme music is composed by Luis GERA special thanks to the Pushkin Brass Malcolm Gladwell, Jacob Weisberg and Mia Lobel. I'm Noah Feldman. You can follow me on Twitter at Noah R Feldman. This is Deep Background