[00:00:32] Speaker A: You are listening to right on radio on KFAI, 90.3 FM and streaming live on the
[email protected]. dot I'm Eric Zimmerman. On tonight's program, Josh talks to Peter Godfrey Smith, the best selling author of other minds, to discuss his latest work, living on earth. Forests, corals, consciousness and the making of the world.
The planet we inhabit is significantly the work of other living beings who shaped the environment that we ourselves later transformed. Godfrey Smith takes us on a grand tour of the history of life on earth. He visits rwandan gorillas and australian bowerbirds, returns to coral reefs and octopus dens, considers the impact of language and writing and ways the responsibilities our unique powers bring with them, all of this and more. So stay tuned to write on radio.
[00:01:40] Speaker B: Welcome, everyone. I am pleased to be joined on this episode of write on radio with Peter Godfrey Smith to discuss his latest work, living on life, consciousness and the making of the natural world. Godfrey Smith, the scuba diving philosopher who examined an alternate evolutionary pathway of sentience with octopuses in his book other minds and how consciousness shaped and was shaped by animal bodies and metazoa, now takes that line of questioning a step further, asking how has life shaped and been shaped by our planet? Instead of looking at life solely as a byproduct of random molecular circumstances on the planet God, Smith proposes viewing life as an ongoing active cause in evolution outcomes. Humans belong to the infinitely complex system that is the earth, and our minds are products of that system, but we are also on also an acting force within it. Pierre Godfrey Smith, welcome to write on radio.
[00:02:35] Speaker C: It's a pleasure to be here.
[00:02:37] Speaker B: I want to start by asking about your personal reaction when encountering stromatolites in Shark Bay. How did that shape the way you connected to the past of our planet with its present?
[00:02:52] Speaker C: When I saw the stromatolites at Shark Bay in Western Australia, they're pretty quiet looking organisms, or rather, colonies of organisms. They sit there looking like outsized aquatic mushrooms or mounds. One of the first things that occurred to me was a scene from the David Attenborough tv documentary from decades ago. Life on Earth, which I had been brought up on.
It came out at the end of the 1970s, and Attenborough's life on Earth was one of the inspirations for this book. Living on Earth. Attenborough, like as I did, reflected on the fact that these nondescript looking organisms, or again, colonies of organisms, had had really an extraordinary effect on the history of the earth, not just the history of life, but the history of the physical place that we live in the earth. The cyanobacteria that are part of the stromatolites were the they or their ancestors. It's hard to know exactly who got this going, but they began emitting oxygen gas into the atmosphere in much larger amounts than had been there previously. It was a very. There was almost no oxygen in the atmosphere on Earth before these guys began their action. They invented a form of photosynthesis, which released oxygen gas.
And that set so many things in motion, it made animal life possible. We need oxygen. Animals need oxygen. It also changed just the physical planet. The kinds of rocks that exist, the kinds of cyclings of chemical elements that move through the atmosphere, in the earth's crust and deeper into the earth. The whole physical nature of the earth was conditioned or affected by having this very reactive gas in the atmosphere. And when you look at the stromatolites in Shark Bay, you're really. You're looking back into the beginning of one of the most important events in the history of the earth. Not just for life, but for the whole planet.
[00:05:12] Speaker B: At the opening of your chapter, Earth enlivened, you mentioned how living organization is a long running feature of our universe.
There's discomfort for some in grouping humans into the category of life alongside bacteria. I was wondering if you could talk about the significance for us to think about life in broader terms.
[00:05:32] Speaker C: Sure. It was a sort of surprise, not really a surprise to me, but just a shift in perspective when I thought about that. That chapter opening describes a moment. I was in a talk at a university in the US, and there was a dinosaur guy giving a talk about the history of life. And he did the thing that people often do, which is completely reasonable and informative, which is to emphasize what a tiny fraction of the earth's history includes. Us. Us humans, homo sapiens, our species. And that's true. We do sort of rush on at the end of the history, but it is possible to think about broader senses of us. There's the US of humans, there's the US of mammals, there's also the US of animals. And making that step even before we get to bacteria and other non animal forms of life, that step already gets you to a big chunk of the earth's history. Animals are probably roughly something like of the order of 650 million years old or something like that, which is itself a pretty good chunk of the earth's history.
But a much bigger part of the earth's history is taken up by the presence of some kind of life. It's a majority of the history of the earth. Surprisingly, it didn't take long, it seems, after the earth formed, for life to come onto the scene. It's been there for something like three quarters of the total. Now, that itself I find very interesting. But when you think about the universe, the whole universe, all of known time, it's still the case that life, at least, is a pretty decent long term tenant. And animals to some extent too. The universe about 14 billion years old, something like that. And even though in spatial terms, life is probably a tiny, tiny fraction of the whole, in temporal terms it's not a tiny fraction of the whole, it's of the order of. About a quarter of life has been around for something like a quarter of the totality of known time. Now, as you say, it's possible to say, well, big deal. I mean, life could be just a kind of inert, passive slime that doesn't do anything, and it could have been there for a long time.
One of the things I want to emphasize in that chapter is the fact that life, pretty much ubiquitously, or at least cellular life, life that includes a metabolism, living things have a capacity to sense, even bacteria, even archaea, the simplest kinds of living things, have some capacity to sense in every case, as far as we know, and to react to circumstances around them. So what we're thinking about, when we think about the long term presence of life is the long term presence of something with the beginning of a point of view, the beginning of a perspective, the beginning of perception and action. So I do want to at least put on the table and reflect on that sort of huge span that life in general, life as a whole has been around for, not just in the history of the earth, but in the history of known time.
[00:09:12] Speaker B: You discuss the Gaia hypothesis in this chapter, the theory that earth behaves almost like a living organism. How do you reconcile the idea of earth as an interconnected system with the concept of teleology in nature?
[00:09:29] Speaker C: I think that there's a very, firstly, I think there's an important role for a kind of, or an approximation to teleology in nature.
One of the historical paths that I want to, that I spend quite a bit of time charting and thinking about is the history of action and what we might refer to as the history of intent, the long term history of acting with intent on the earth. If we go back to those bacteria which have some ability to sense what's going on and respond to what they sense, many bacteria can follow gradients towards beneficial chemicals and away from less beneficial chemicals. For example, there's a kind of glimmer of goal directedness in that kind of behavior. And if that kind of behavior is very, very old, billions of years old, as it seems to be, then that's the very early history of acting on the basis of a goal, doing something for a reason, where reason here doesn't just include the cause of something happening, but an outcome that the action is directed towards.
So that's very old. Animal action includes elaborations of this. One of the transitions I talk about in quite a bit of detail is the transition from actions based purely on habit, actions based on what's worked well so far in the past, and actions based on something like a plan or a model. Actions that can be based on courses of action that have never been done before, but are aptly directed towards an outcome that the agent has in mind. Now, the. The transition from the absence of life to life with those beginnings of goal directed behavior. The transition from animals that act purely on the basis of habit to actions that are based on a plan.
The transition in the human case from more individualistic forms of action to highly socially coordinated and linguistically organized action. All of these you can see as stages in the history of choice and the history of things happening for something like a purpose, things happening because of the effects that they are directed on. Now, I think that it's possible to overextend the role of teleological ideas when thinking about nature. I don't think large scale systems like the earth do things for a goal in the way that living organisms do things for a goal.
And I'll talk in a moment about the Gaia hypothesis itself. So one of the things I think it's important to try to do in thinking about the history in this way is tread a middle path between dismissing the idea of goal directedness and purpose in nature, even in cases where it really has an important role in cases of choice by animals, actions by living things that have been formed as a consequence, formed by their consequences, in a sense that have been shaped by the effects they're likely to have, that's real and important and a factor in the history of the earth. And then there can be a tendency to overextend teleological thinking, to apply it uncritically to systems where it doesn't really belong. Now let's talk about Gaia a bit. This was one of the most interesting parts of the book to write and think about. The Gaia hypothesis was introduced in the 1970s by James Lovelock and Lynn Margulis. As you say, the idea that the whole earth functions in a way that is akin to or literally is a living system, a living organism. It's not just that the earth is made in part of living organisms, but it's something like an organism in its own right.
People criticize this extensively as being something that could never evolve the earth. One system, not part of a population of reproducing organisms, could never evolve an organism like structure at its own level or in its own right.
People also, in some cases, regarded it as a sort of fairly flaky idea, loose thinking.
In recent years, a number of people, including Tim Lenton, who was very helpful to me in the writing of this book.
He's a UK scientist.
Lenten and others have argued that, look, you might not think the earth is an organism, but there's really something that has to be explained here. There are these life friendly feedback processes that are all around us on earth. The earth's atmosphere, its temperature, the salt level in the oceans, the cycling of various elements through the system. All of these things are tuned in a way that is somewhat helpful, at least to the continuation of life. So you have to say something about those feedback systems, those cycles when they're real. And in the second chapter, I found myself having to sort of tread a cautious path. I'm still skeptical about Gaia in its strong forms.
I think that some of the things that look like they're life friendly on earth really do just have to be seen as luck.
Luck seems like a bit of a non explanation to some extent, but I think that's what a good part of it is.
And then there's a side of a story that I confess to still finding very intriguing. I think there's a possibility that we don't know the whole story in some aspects here. So this is a very exploratory discussion, and it's Gaia skeptical for the most part, but not Gaia dismissive.
[00:15:57] Speaker B: Okay, so in your chapter, Orpheus, the mythological figure of ORpHeUS, is woven THRoughout this chapter. How do you see this ancient myth connection to modern understandings of music and communication in the natural world?
[00:16:09] Speaker C: It's not that the details of the myth have particular significance.
The thing that made the OrpHeUS image completely irresistible to me when writing this chapter is the fact that orpheus, the mythical figure, played the lyre. And he could use his lyre to charm pretty much everybody and everything around him. In some versions of the story, he could even charm inanimate objects like stones around him. He played the lyre, and in that way, he's a kind of symbol of the power of music, its seductive power, its power over human choices and so on. And the animal that features centrally in that chapter is a bird called a lyrebird. Now, the lyrebird is not called a LyrebiRd because of its especially seductive song, although it is in some respects the, well, the most extraordinary exponent of birdsong that there is.
Its body has a lyre on it. There are these two tail feathers called the lyrate feathers, which look just like, well, not just like, but quite a bit like the wooden, curved parts of the musical instrument, the lyre. So I think of this as a kind of extraordinary piece of evolutionary alchemy in a way where, again, just I don't think there's a kind of hidden purpose or message being sent to us by this. I think this is just fortuitous, but it's a pretty remarkable, fortuitous fact that this bird, which has, well, the lyrebird special in a couple of ways. Firstly, it's a representative, one of the few representatives of a very early branching part of the evolutionary tree of songbirds. It's only distantly related to other songbirds, and it has some features that make people think it is in some ways a relic of an early form. So it's a kind of early exemplar of the songbird style.
The capacity they have to imitate other birds is also completely extraordinary. If you follow a lyrebird around, often they produce a sequence of half a dozen or so calls of other birds in sequence, perfectly mimicked. And there's a paper that's been written showing that even birds of the other species who are being mimicked can't always tell when it's a lyrebird, rather than their own species doing it. So they're extraordinary mimics.
They are representatives of an early line in songbirds, and they have a lyre attached to their bodies so that they are multiply significant in the book. And I use them in the chapter that they figure in is a chapter about display, evaluation, expression, that whole side of behavior, that part of the evolutionary history of behavior.
[00:19:33] Speaker B: I want to probe this a bit further. So you mentioned Richard Prone's concept of aesthetic evolution. How do you believe this aesthetic component shapes the survival and evolution of species beyond birds?
[00:19:49] Speaker C: Well, one of the cases that, one of the cases I say a bit about in that chapter is far from birds and that's flowering plants and the relationship between flowering plants and insects. If we look at the history of the history of the sort of living transformations of the planet, beginning with the cyanobacteria and the release of oxygen into the atmosphere as a kind of very important early stage and ending for now with human action as a transformer of the planet. One of the important stages in the middle was the evolution of what we might call modern forests, forests of the kind that are familiar to us now of the order of 100 million years or so. Back is when these forests began to become important.
And forests of this kind are made up in large part of flowering plants. Flowering plants evolved back around this time, a bit earlier, but then becoming prevalent around 100 million years ago.
And one of the things that flowering plants did was enter into this complicated, semi cooperative relationship with insects and other animals as pollinators, and to some extent, also as spreaders of seeds. But pollination was pollination by insects and some other animals was a really important invention. Now, this required that the plants make themselves attractive, that they indicate to particular pollinating organisms, especially insects. Again, their suitability, their appeal to those insects as places to feed, as plants to visit. And that was another kind of case where organisms made themselves appealing. They produced displays, flowers, that were appealing to others.
And this fact became one of the transforming agents at that stage in the history of the earth.
[00:22:10] Speaker B: The chapter consciousness discusses the evolution of consciousness across species.
What key indicators do you identify as markers of consciousness? How do they manifest differently among animals?
[00:22:24] Speaker C: We're using the word consciousness here in a broad sense. It's worth emphasizing that at the start, and that's the way the discussion has gone in recent decades. We're just talking about which animals feel the events of their lives as they occur.
Which animals? Is it something it feels like to be that animal?
The list of animals for whom a kind of a sort of strong, maybe, at least, is an appropriate response to that question.
It has been growing a lot in recent years. There's a lot more animals for which there's, what we can say is a realistic possibility, or a decent possibility of them having consciousness, in a sense, than we had thought before.
A lot of the work that has been done directly looking for this feature concerns felt pain or pain like states. There's now a very convincing paper on the presence of something like acute pain in octopuses that was published by Robin Crook a couple of years ago. So that was published after the books I wrote that were more about octopuses, other minds and metazoa. The case for octopus experience, I think, has been strong for quite a while. But in the particular case of pain like experience, it got much stronger when Robin Crook published her paper. Maybe I'll say a bit about the methodology of the paper in a second, but before I do that, the kind of frontier case now, or at least the case that has perhaps even left the frontier, is some kinds of insects. There's now some fairly convincing work on something similar, something like acute pain in bumblebees. That was work that came out of Lars Chitka's lab a couple of years ago.
There's been, for a while, pretty good evidence that various crustaceans, crabs and lobsters, hermit crabs, are the ones that have been worked on in a lot of detail by Robert Elwood.
There's pretty good evidence that they have something like pain. Now, pain is not all there is to experience, of course, but it's something that is obviously important. So it gets studied a lot, and there's a fairly well worked out, still controversial, but fairly well worked out list of things you can look for in experiments that seem to be fairly telling. In the case of pain, let me say a bit about how the octopus experiment worked, and perhaps that will be a good example.
What Robin Crook did was she gave some octopuses a little injection, a small one, in the arm of acetic acid, which is vinegar. So it's not a seriously aversive event, but something the octopuses seem not to like. Okay, what is the nature of their not liking it? Is it just a kind of reflex? Is it just the kind of pulling away that we might say is not associated with felt experience at all? Well, no, it turned out that it was quite a bit more complicated response than that. The octopuses would avoid an area, an environment where this had happened, even though it had been an area that had been preferred by them before, they would not avoid that area where this had happened. If this area was then associated with analgesic chemicals in the water.
Perhaps surprisingly, the painkilling chemicals that work on humans often work on animals that are very far from us or seem to work. They do something relevantly similar, and they were seen in the octopuses. The octopuses also tended and protected the injured area.
They kept it away from the possibility of further stimulation.
They wound tended, that is. And there was some physiological evidence as well, looking at what's going on inside the octopuses in response to all this.
So in a case like the crook experiment, you have different lines of evidence, different behaviors, the avoidance, the getting rid of, the avoidance, the wound tending, all of which point to the presence of something like an integrated and fairly sophisticated response to an event, suggesting that it's aversively felt. What they don't like here is the feeling of that, and there's various behaviors that reflect that fact in different ways. Various other animals. There's quite elegant work on trade offs, situations where the animal will adjust their response to an aversive event in a way that trades off different kinds of goods and bads. For example, in the hermit crab work, hermit crabs can be given a little tiny electric shock, and that will lead them to abandon the shell that they're in. Hermit crabs are the ones that. That live in shells discarded by marine snails, essentially. So the crabs will give up a shell if it is associated with an electric shock, but none of it's a really, really good shell. If it's a really good shell, they'll put up with more shock. If there's a smell of a possible predator in the water around them, they'll put up with more. There's a kind of trading off between the apparently aversive nature of the electric shock and the other kinds of goods and bads that are present in the situation. And that also is taken to indicate exactly how to describe it is unclear, but something like an integrated response to an experience that takes into account the intrinsic aversiveness of this thing. Electric shocks don't matter. They just don't feel good. And the relationship between that intrinsic aversiveness and the other positive and negative aspects of the situation, the risks, the quality of the shell, and so on.
[00:28:39] Speaker B: Okay, so that brings up a lot of thoughts in my mind about the ethical implications of using animals in experiments. What do you think are the most compelling arguments for redefining these ethical boundaries?
[00:28:51] Speaker C: Yeah, I think we should reset the ethical boundaries.
In the part of the book that's about animal experiments, the focus is especially mammals. So there are lots of cases, including the ones we've just been discussing, where I think there's a reasonably good chance that the animals in question can feel pain, but still a good deal of uncertainty around the cases. In the case of mammals, I take it that there's much less uncertainty. There's essentially no uncertainty.
After finding this quite a hard problem to think about, especially because a lot of what we know about animal minds has resulted from work that has been bad for the animals in the experiments, I found myself in a situation thinking that we should abandon a great deal or at least massively reduce the kinds of experiments that we do wherever sentient animals, especially mammals, are put through very unpleasant procedures in the service, essentially of scientific curiosity to try to work out what is going on.
Now, in the case of mice and rats, the mammals that are most widely used.
There's an argument that I spent some time thinking about that has been discussed by a few people, but especially Philip Kitcher, the philosopher, where he says, look, one thing we might do is not so much eliminate the use of the animals in the experiments, but change the balance of positive and negative experiences greatly, not just in the context of testing, but for the whole lives of the animals. Give the animals in our labs an enviable life in a sense, or at least a life that is favorably comparable to the lives of their wild cousins.
And partly as a consequence of the approach that I take to some ethical questions involving farming in the same part of the book, I do take that argument very seriously, the way I approach questions about farming, the farming of animals, is a way based on what I refer to as whole life reasoning. It's not just the stages in which animals are killed that we should be thinking about when asking questions about ethics and farming. We should be thinking about the whole lives of the animals. And the main point of that part of the discussion, the main part, the central argument of that part of the chapter, is that a great many animals in industrialized farming today in the world live lives that are not worth living, and that we should radically change farming so as not to be putting animals through lives of that kind, where it's the whole life in question that's not worth living. Now, if you apply a kind of whole life reasoning to questions about farming, and when you do that, you wind up with a very different attitude to industrialized farming on one side, and best practice humane farming on the other side, situations where animals really are given a life worth living. If you apply that kind of reasoning to the farming case, you should really apply the same kind of thinking to the experiment case and ask whether there can be lives definitely worth living, that animals in experiments might have. And in the case of mice and rats, I take that possibility seriously. In the case of other mammals used in experiments, there are still lots of small monkeys used in experiments in the US, many, many thousands. There are still lots of dogs and a fair number of cats used in experiments in the US in particular.
In those cases, I think we should just stop. I find myself looking pretty much heading towards an abolitionist view about the use of those kinds of animals in harmful experiments. It's not the same when the experiments are not harmful, when they're just behavioral experiments, animals living in sanctuaries and the like, but the sort of biomedical experiments that involve invasive procedures and harm. I think in cases where a whole life argument can't be made that the animal has a really good life. On the whole, we should radically reduce the use of animals and experiments of that kind.
[00:33:42] Speaker B: Climate change. Climate change and habitat destruction are intertwining issues. How do you envision the future of conservation efforts in mitigating these threats to wild nature?
[00:33:52] Speaker C: Okay. I think that it would be good if there was a partial reweighting of priorities in this area.
I think that climate change is real and is definitely a problem, especially in relation to the kind of speed of change that we're going to be seeing. But I've become concerned at the way that climate change swallows up other environmental questions and has dominated the way that people talk about environmental policy, especially in progressive circles. People think of climate change as the problem, and I would like to see a little bit of a reweighting where we take at least just as seriously habitat destruction of the, you know, the familiar and pressing kinds, deforestation, the loss of wild species, the pollution of waterways, the kinds of things that were front and center in environmental policy before climate change came to dominate.
Now, part of the reason why I think this is that I think that climate change is a truly global problem. It will take a global solution. I expect it to require some further technological advances before we can really fundamentally change emissions, the emissions that we're producing, and habitat preservation.
It's a global problem in some ways, but local action is entirely meaningful. In the case of habitat preservation, a relatively small locale or a single country, a single state, even a single city, can do things that can prevent the loss of species.
The loss of bird species in nothing. Well, the loss of just bird numbers in North America is now an extremely troubling phenomenon. I have some figures in the chapter about that. Really large numbers of birds have declined since the 1970s. The loss of insects is equally troubling.
There's a kind of pressure being put on wild populations that I think of as extremely problematic. And once species are gone, they're gone. So I would like to see a bit of a reweighting where climate change is taken seriously as a global problem, requiring coordinated global action and probably some technological changes. But along the way, we spend much more time and energy trying to prevent deforestation, prevent pollution, prevent the loss and pressure being put on wild species. So something of a reweighting there.
[00:36:50] Speaker B: This has been my time talking to Peter Godfrey Smith about his brilliant new book, living on consciousness and the making of the natural world. Peter, thanks for being on the program.
[00:37:01] Speaker C: It was a pleasure. Thanks for having me on.
[00:37:03] Speaker B: And now this.
[00:37:25] Speaker A: You have been listening to write on radio on KFAI, 90.3 FM in Minneapolis and streaming live
[email protected]. dot I'm Eric, and we would like to thank Peter Godfrey Smith and all our listeners. Without your support, KFAI would not be possible.
[00:37:44] Speaker B: Yappe Sadeena.
