The Future of the Human Climate Niche with Tim Kohler & Marten Scheffer

Episode Notes

Humans, like any other organism, occupy a niche — a “Goldilocks Zone” for which our biology is suited, relatively to the extreme diversity of habitats on Earth. But to understand the natural habitat of human beings we would first have to perform a comprehensive survey of human settlements throughout history and prehistory, looking for patterns in the climate data. No one did this research until very recently, and what they found surprised them. Human life, especially the outdoor work like farming on which our societies depend, is suited only to a very narrow band of temperature and moisture levels, a tiny area on Earth’s large surface. The implications are severe and ominous when held in light of climate forecasts for the coming decades: a major and unprecedented set of challenges that will test ability to innovate, adapt, and migrate as the world around us changes.

This week guest’s are SFI ecologist Marten Scheffer at Wageningen University and SFI archaeologist Tim Kohler at Washington State University. In this episode, we discuss the past and future human climate niche, how our ability to adapt to climate change is hampered by the psychology of sunk costs, and how a better understanding of social tipping points and collective information processing at the scale of civilization could help prevent the catastrophes ensured by business as usual.

Welcome to COMPLEXITY, the official podcast of the Santa Fe Institute. I’m your host, Michael Garfield, and each week we’ll bring you with us for far-ranging conversations with our worldwide network of rigorous researchers developing new frameworks to explain the deepest mysteries of the universe.

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Papers discussed in this episode:

Future of the human climate niche

Sunk cost effects and vulnerability to collapse in ancient societies

Social norms as solutions

Scale and information processing thresholds

Tim Kohler’s Website

Marten Scheffer’s Website

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Episode Transcription

Michael Garfield: Tim Koehler, Marten Scheffer, welcome to Complexity Podcast.

Tim Kohler: Thanks for having us.

Martin Scheffer: Thanks. Happy to be here.

Michael Garfield: I would like to discuss one particular paper, your paper on the future of the human climate niche that you coauthored with Chi Xu, Timothy Lenton, Jens-Christian Svenning, but there's a number of other papers that either or both of you have worked on over the years that I think linked to this one really well. So, we will be dipping into different areas of both of your research careers and we'll try and sort of constellate things and expand on some of the issues that you raise in this latest piece.

Tim Kohler: Sounds great.

Marten Scheffer: Sure.

Michael Garfield: Excellent. Well, I'd like to start first by asking the two of you how this particular paper came to be. My understanding is that it had at least some of its origin story in an SFI working group.

Marten Scheffer: Well, it's a long story. It started when I was at the conference of tropical ecology in Mérida in Mexico, and it was awfully hot and humid and I started wondering, is this good for humans? I started looking for literature, but I couldn't find any really good stuff, and then I forgot about it. Then later, working with Chu Xi, I thought, let's go back to the work we did on tropical rain forests, where we were characterizing the climate niche of the rainforest, and we did the same for Boreal ecosystems. So, let's try it for humans. I didn't think much of it, but a very clear pattern came out and it turned out that humans were concentrated very much in a particular temperature zone. And then we started wondering whether it was a coincidence perhaps, and thought, well, let's go back in time. But we didn't know how to go back in time. So that's when we called Tim Kohler. And since it had to do with climate, and we didn't know anything about climate, we needed Tim Lenton. And since we didn't know anything actually about where humans live, and for what reasons, we had to call on Jens-Christian Svenning.

So, then we had a really a great team and we worked for a few years on this. At some point we thought it was a great idea to have a workshop about it at SFI, but by the time that we finally made it to SFI, the work had basically been done and we moved onto the next topic which we’ll produce by pursuing it, and which was fantastic, also. The title of that paper, so far, is Survival of the Systems. That that's how it goes in science, right? You have ideas and then they finally you come together but then you're already onto the next idea.

Tim Kohler: So, in the end, there will probably be on the order of three, maybe four papers coming out of this working group. I think SFI will be quite pleased with the performance of this working group. By the time we got to Santa Fe, I think, I feel like our main job with respect to the paper we're discussing today was to see if we could poke some holes in it. Are there problems with this? What could possibly be wrong? We were, we were there primarily as critics, but also to see whether or not we could extend it meaningfully in other directions. We wanted to basically push and pull on it, and see where we went. And one of the things that came out of that was working with some new results from crowdsourced archeological research called ArcheoGLOBE, which coincidentally was published shortly after our working group. So, we could draw on their results to make estimates of how dense people had been in various portions of the world over chunks of time, going back to the beginning of the Holocene, that's to say 10 12,000 years ago. So, we drew on those results, as well as from results from more traditional land use patterns that have been attempted to extend back into prehistory, called the HYDE database. And we saw somewhat similar results from both of those, much to my surprise.

They showed that in fact our preference for this relatively narrow temperature band between roughly 11 degrees centigrade and 15 degrees centigrade has been constant, well back into at least the mid Holocene, when a lot of the world's populations were still hunters and gatherers. 6,000 years ago, agriculture was just spreading across Europe, and just beginning to spread up from Mexico. So, by far the majority of the people in the world at that point were foragers, farmers, fishers, hunters and gatherers. They could be highly mobile, they can move wherever they want, and yet they stayed within that climate ban. Much to my surprise!

Michael Garfield: Let's talk about that climate band as defined by this paper. The way that this particular piece has been reported, it succumbs to some of the kind of a perennial problem: I think science journalism doesn't really get under the hood, and look at how you came to the understanding that you came to. So, I'd love to hear how you went about defining this climate niche in the first place.

Marten Scheffer: So, the way we looked at this was just by looking at population density, distribution of humans, not in space, but in climate space. You can make one axis which is, for instance, a mean annual temperature and the other axis, which is mean annual precipitation, and you can think of more axes and then you look in that space. What kind of combinations are available on the globe? How many places have those particular combinations? And then you look at where the people are, and from that you derive a preference. That's basically ecology, right? And we took the big step to say, as ecologists, well maybe humans are just another species, and let's see if they have some preferences, too. We didn't think that would lead to much because we know people are living everywhere. They live on the poles, and they live in the desert. But to our surprise, the distribution of people in the climate space was not at all random, there are very clear preferences. And with Tim Kohler's expertise, we took a look back in time, and what’s really surprising to see that we still have the same apparent preferences that we had 6,000 years ago. There must be something to that, we thought because we can move everywhere. We have all kinds of innovations, and still we have those same preference. So, that’s what got us on that track, that was the basic method. Of course, there is a lot of work and a lot of details to it because if you go back in time, and you want to reconstruct where humans were back in time, that's not so easy.

And also, you have to project that on how the climate was in those places where the people were back in time. You really need this combination of expertise in paleo climate, in archeology. And that’s what we could do with this group.

Michael Garfield: I thought it was interesting to note, you make a point in this paper that it's not that human beings are concentrating in the areas of greatest soil fertility.

Marten Scheffer: Yeah, well of course you start looking for other things that are obvious. Where are the best soils? Where is enough rain? Where is the primary productivity, actually? We’re a large world. Where do the plants grow best, which is the basis for agriculture? None of those seem to be definite answers, but what's actually quite surprising is that temperature appeared so important. We were also limited in terms of rainfall; when there is no rain in the desert, there is no people. The temperature was perhaps the most surprising, and also one of the clearest patterns.

Tim Kohler:  For me, one of the most interesting figures in the paper is the first figure. That figure shows that if you just look at the distribution of the available land surfaces in the world with respect to mean annual temperature and mean annual precipitation, it's spread out over a vast climate space. But then when you look at where people are now or where people were 6,000 years ago, we occupy a very narrow portion of that available niche. And, when you look at our distribution, you also see that it's quite similar to the present distribution of crop production, the present distribution of livestock production, and the present distribution of GDP. But, it's very dissimilar to the distribution of soil fertility, or net primary productivity. So, our crops in our livestock are selected for a specific band within the available niche, within the available soil fertility, and net primary productivity. So, it's worrisome to think about the future and where our crop production and livestock production will go, as that climate niche begins to move on the surface of the earth.

Michael Garfield: That brings us to the meat of this paper, which is the ominous forecast that the next 50 years of climate change are going to result in a pretty significant redistribution of this niche across the surface of the planet. What models did you use in order to investigate this?

Marten Scheffer:  We just followed the standard climate models. We didn't compute the climate in the future, which is used to IPCC models. We looked at different scenarios of various degrees of warming, and found that for each degree of warming you can roughly say that about a billion people get into serious problems, about a billion people need to move from this same climate niche that served us well for the past 6,000 years. So that’s the analysis of the niche. And it became such big numbers: for three degrees you’ve got 3 billion people in serious trouble. We also wanted to look at a very different, very simple approach, and just look at the hottest places that we can find now on earth, which have a mean annual temperature of above 29 degrees centigrade. We looked at how large the geographical area will be where those temperatures will be felt in the future, and for a three degree warming, you see that covers an area where about 3 billion people would live, and it’s very hard to live at that temperature.

Tim Kohler: So those temperatures on the globe today are mostly restricted to the central Sahara in Africa. But this paper shows that, under the “business as usual” or also sometimes called the” worst case scenario,” those temperatures are going to expand greatly in central Africa, but also extend over onto the Arabian Peninsula, portions of Southern Asia, portions of Northern Australia, and a large portion of Amazonia in Northern South America. So those places are going to be very hard hit under the “business as usual” or “worst case scenario,” which we certainly hope we can avoid.

Michael Garfield: Looking at figure four in this paper that shows the current suitability to the human niche and then the projected 2070 suitability and the difference between them, just at a glance it doesn't look like we've lost much terrain in a temperature sense, right? But I understand that if anything, maybe by temperature, more of the earth is actually suitable, but it's not just that one dimensional analysis. And you do go into some detail in this about why this particular projection is likely to be so difficult, and it has to do with the distribution of the projected population growth, and the difficulties of migration. It's not as simple as just saying, well, Hey, there's a bunch of new land up there for you in Canada and Siberia, and why don't you just move three and a half billion people up there? So, I'd love to hear you get into more of the multidimensional complexity of this situation and how it's not as simple as just saying, well, Hey, there's going to be a ton of new arable land.

Marten Scheffer: Well, yeah, the point you make is very good, of course. Some places become worse and other places on the globe become better. So, what's the problem? We just have to move. Well, that's not so easy. People have always moved in the past in response to climatic change. It's strange that we never want to talk about it. When we think about climate change, we stress two things we should do: we should limit it, and we should adapt locally to the new climate. I think our paper suggests that there may be a third thing that we should do, and that is prepare ourselves for organized migration. Think about the best way for some redistribution. Looking at the data that we get, it's hard to imagine accommodating different degrees of climate change without at least relocating hundreds of millions of people, at least. And that's a kind of a taboo, no-go area of discussion. I think with our results, it becomes clear that we should start thinking about the best way to do that. Migration can bring lots of good things. People don't like to go away, they don’t go away unless it's really needed, but also know of many good things that have come from migration. But it can also cause tremendous stress and conflict. So how do we prepare ourselves for that? How we deal with that globally will make a lot of difference.

Tim Kohler: Yeah, and I might point out that even within countries we can see that there might be some demand for relocation. If you look just at North America, you can see that the Southern portions of the United States, on that figure four, look as though they are going to become extremely uncomfortable under “the business as usual scenario” in 50 years. Whereas the Northern portions extending on into Southern Canada look like they're going to be increasingly attractive. So, the stresses and strains of migration are probably easier to manage within nations. Between nations, they get much more difficult, but we know that even within United States, movement of people from place to place has been stressful and politically unpalatable at times. We have the example of the dust bowl, in which large portions of many people in the Southern Plains left for places like California where they were exploited rather viciously by large group growers and other people. You can read Grapes of Wrath and find out the story on the ground. I'd have to say that looking at figure four, this is probably the first paper I've ever published in my life where I'm hoping that we will be wrong, that the future will prove us wrong. We always want our science to be correct, and we hope that the models the projections are correct, but we also hope that the future is not what we're predicting in this, which is the “worst case scenario.” We're hoping that indeed there can be adaptation and mitigation that will make things less dire than they appear to be in these maps.

Michael Garfield: No doubt. But you introduce a fold into this paper, which is the unwillingness of people to move, that typically migration is avoided for as long as possible. And that's where I'd love to link in this other piece that the two of you coauthored with Marco Gunston for Current Anthropology back in 2003: “Sunk Cost Effects and Vulnerability to Collapse in Ancient Societies,” because it feels like this piece speaks directly to the psychological dynamics involved when it comes to getting people to leave their homes and their communities under even extraordinary strain. Would you care to unpack the thinking behind this particular paper?

Tim Kohler: Let me start on that because that used a portion of one of the areas I work in as a test scenario. The larger concept has to do with sunk costs. The idea that people weigh future actions taking into account their past investment, which is a completely irrational, non-rational thing to do. In fact, people should take into account the future circumstances and their projections of the future, not how much they have invested in a particular landscape. But this sunk cost effect means that people are less likely to move, the more they have invested in a particular area. The area we were looking at was a particular area that was investigated by the Dolores Archeological Project in the late 1970s and early 1980s, and this area was inhabited very densely by Puebloan populations from about 8,700 to 900, and towards the end of that period, climates turn quite unfavorable for agriculture, and these people were heavily reliant on maize agriculture. So, they began to leave this area.

But what we found is that in those places where there was the greatest investment in structures, in fields and infrastructure in general, people stayed the longest. They were the most reluctant to leave. And this points out that people leave places for essentially two different reasons. First of all, they do make some rational calculation. Are we able to make a living here? But secondly, they're highly conformist in their decisions. When people finally decide to leave, many more people leave than probably would have had to, based on the rational calculation. But at the beginning of a migration process, there is a much less migration then you would expect. So, there are thresholds here for migration, and they're very nonlinear. That will lead perhaps to very interesting dynamics as we move into the future and see what happens with some of these areas on our map that are red. Will people leave as they begin to turn red? Probably not, they will probably stay as long as they can, which might mean a massive and more uncontrolled and more unplanned migration, if don't begin to do something about the conditions that are provoking the migration in the first place.

Marten Scheffer: You could also look at the same phenomena from a very different angle. The idea that we have sunk cost phenomena means that we don't want to change doing things. This is also true for ways of living for things you believe, for your investment in your belief, your way of living. We know we should change the way we live to control climate change and biodiversity loss, but it's very hard to do that. And so that's another face of the same problem. It seems very difficult to change. It’s very interesting now to see in COVID crisis time, that actually some things that we thought were completely unthinkable suddenly happened. So, yes, we can, we can make all kinds of changes, but we are very reluctant to change our way of living, to abandon some things even if we know rationally that that would be best.

Michael Garfield:  I think the two of you hit the two sides of this idea that I wanted to touch, that this particular paper mentions. It says the model predicts that sunk cost effects can lead to growth of settlements to a point where they are about to overexploit the resources, and at this point resilience, the basin of attraction, becomes very small and adverse stochastic effects will tend to induce collapse. You know, for the last several weeks in the Transmission Series that I've been hosting with David Krakauer, this has been coming up time and time again. I'm glad to see in a way that the pandemic has illuminated for people the ways that we have tuned our society to brittle-efficiency. And yet, like you said, the more we benefit from economies of scale in time supply chains, and so on, these features of our global economy as it has been, the more likely it looks like we are making ourselves vulnerable to what for many people would be a surprise shock, like the pandemic. Even though there's lots of, “I told you so,” going on right now.

But that also, like you mentioned to us now, it makes us somewhat more likely at a crisis of collective decision making, to continue with business as usual because it is harder without the crisis to climb down, off of the local optimum on your evolutionary fitness landscape. I think that's sort of the beauty of this paper, how it explains why, en masse, it's so difficult for us to do what we understand to be the right thing, but to make that decision as individuals. And so that brings me to … speaking of collective action problems, Marten and you were coauthor of a piece in Science Magazine back in 2016 on social norms as solutions. And I feel like there is sort of a ray of hope here. I mean, there are 26 authors on this article, which presents its own collective action problem. Could you talk a little bit about this ‘policies and large-scale behavioral tipping points’?

Marten Scheffer: Well, you mentioned the number of authors on this. This is a dynamic organized by the Beijer Institute of Ecological Economics, and it brings together a bunch off ecologists and economists and various social scientists to spend a long weekend in an isolated Island in the Baltic. Much as people get together at the isolated Santa Fe Institute in New Mexico, but then we were in the Baltic. There is nothing there. We have to cook our own stuff and so it's a long boat trip and then we just talk and talk about something that we find interesting, and each year a paper comes out of that.

And this time we were interested in this question, and the paper originally was called The Non-Smoking Planet. We were interested in the question, why do social norms change, sometimes? Why do we suddenly have no smoking in public places across Europe? It's sacked in someplace, and then it's everywhere. Why do those kinds of transitions happen, and why do they not happen very often, and what is needed for them to happen? So, we looked through all kinds of cases and worked from examples rather than theory. When did we see a transition to no littering, or the transition in ancient China that ended the foot binding of little children? Why did it not happen for a long time, and why did it suddenly happen?

And the conclusion of that paper, looking across all of those cases, is that people stay with a particular way of doing things, but the resilience of that thing becomes less and less, the resilience of the idea that we can all smoke in public places is reduced, because we start understanding how unhealthy it is. You hear more and more stories, and then you get desperate because when you want to make a policy, you realize that nothing is changing. It looks like nothing is changing, but really something is changing in the background, it's the resilience of the old way of doing things. And when time is ready, then you can have a rapid cascading change. In the beginning maybe, you need to police it a bit, make sure that people don't start smoking in a public place, but very soon you don't have to do that. Now if I light a cigarette in a school or in university, everybody looks angry at me, so I immediately put it out. It has become a social norm. Of course, when we think of sustainability of the planet there are many things that many people realize we need to change. We should change this or that. We should, and not much is happening. Things are happening in small groups, people become vegan and you get more and more people becoming vegan, but it's not spreading across the whole globe, and it looks like nothing is happening. But things are happening, and at some point, the resilience of the ‘status quo’ will be diminished, and the good news is that then big things can happen pretty rapidly.

Michael Garfield: One of the points in this paper is about the visibility of a new behavior, and how much more difficult it is to change something if people cannot observe their neighbors making the change. There is mention here about customers of a major electric utility who were much more likely to participate in a program preventing blackouts when their neighbors could tell who signed up.

Marten Sheffer: Yeah, sure. There are a lot of things we know from social psychology and I remember talking to Lynn Ostrom before she passed away about this, and it's a point she would, she would emphasize that visibility of your behavior is very important. It just makes it easier to change some things than other things. Smoking in public places is very visible, but you can, you can do something about visibility. You can make the behavior of people in some sense more visible. Like in that example.

Michael Garfield: This seems like a particularly sticky issue when we're talking about long-term climate modeling because people tend to get lost in the weeds as I know you both know, about the details of the model. In earlier episodes when I had a Mirta Galesic on, she was talking about the calculation that each of us are kind of unconsciously running at all times about social truth versus factual truth, and, like you said, the importance of conformity and how –– when there are not imminent negative consequences to holding a counterfactual belief or behaving as if you do –– then people will choose the politically motivated bias over an adherence to empirical reality. So, I'm curious how the two of you see opportunities for this kind of behavioral tipping point. This far out, when we're talking about 2070 –– and all of this is for so many people very vivid and real, you know? If you're living in one of these zones where they have these extreme heat waves, or hurricanes have gone up by many factors over the last couple of decades...but for a lot of people, it's not as obvious. I'm curious how you imagine we might be able to bring this down to earth for people, without running them over the cliff.

Tim Kohler: You raise a really interesting point, and in archeology we phrase this as the “low frequency versus high frequency change” problem. The increasing mean annual temperature of the earth surface is a very low frequency problem. It's virtually impossible for an individual to sense those very small increases in temperature, even over the course of a relatively long lifespan. But what is salient to people are the severe events, the extreme events that get superimposed on tops of these things. So, you've got a low frequency process moving along, in this case, it's mostly ramping up, then you've got high frequency processes superimposed on that and they're tracking the low frequency process to some extent. But of course, the highs get higher as you move to track that low frequency process. So, the extreme events are going to get more extreme and those are really what people will be keying in on: the heat waves, which have been getting progressively worse in Europe over the last decade or so, he severe storms, droughts, all those things do capture people's attention. They are highly visible, and it's becoming more plausible now than it was just a few years ago to assess the extent to which climate change is responsible for those. This is the attribution problem, that one can take climate models with and without forcing by warming from greenhouse gases, and assess how likely it is, how likely it would have been to have had such a storm or some other extreme event without global warming, and thereby provide an estimate of the extent to which those extreme events can be attributed to climate change. So, this is very powerful, because these are highly visible. People feel them. They're aware of them, unlike the increases in mean annual temperature,

Marten Scheffer: This is a big, big topic that we can can talk a lot about: what is needed to change the behavior of people? But you're entering a big area there: it's not just individual decisions. Of course, policy makes a lot of difference. So, what happens in the world is also to a large extent determined by big firms. There is a limited number of firms that basically run the world. You could say we have democracies, but democracies work in ways that do not simply reflect individual preferences, and then there is the other big issue which is the way that our perception of the world has changed, as a result. For instance, we could explore social media use in many areas, it's a wide-open field.

Michael Garfield: I don't want to leave you on the side Marten, but there's an opportunity here to talk, Tim, about your new paper. This piece on this Seshat DataBank. What I'd like to do first is address in the paper on the future of the climate niche, the alternative to migration which is adaptation, and then return to collective decision making and the scale of human society, and our ability to integrate at that scale in the new piece on Seshat. As you make clear in this paper, it's not just migration. You leave a wide-open area to speculate about possible adaptations that we're able to make in the next 50 years. I have to suffer the Twitter responses to this kind of stuff as part of my job, and somebody pointed out on Twitter that people living in Phoenix and Miami are already living in these kinds of conditions, and they seem to be doing okay. But of course, they're also dependent on agricultural supply from other areas. And so, it's a very complex image. So, I'm curious just to hear your thoughts on the possibility of adapting to this, and what particular challenges you think we would face in doing so.

Tim Kohler:  Well, this is something that, of course the IPCC worries a lot about. One of the great interests of the IPCC is what kind of adaptation can be done to these sorts of changes? How can we face these? How can we do better? And obviously, one can breed crops to attempt to make them productive under higher temperature conditions or different precipitation conditions. One can breed animals in the same way. But it's also believed, and I'm sure this is correct, that there are limits to adaptability. There are limits to plasticity for these various plants and animals. We don't necessarily know, at least I don't know, where those limits lie exactly, but it's highly plausible in my view that not all of this problem can be met just by adaptation. IPCC uses another term which is “mitigation” in a rather special way, and what ITCC means by mitigation is the prevention of greenhouse gases going into the atmosphere in the first place, or perhaps the removal of them from the atmosphere after they've gotten there.

And so one hopes that through adaptation and mitigation, a great deal of the demand that would otherwise be met by migration can be met, but one doesn't know exactly how much and what that will look like because we're looking into the future and we're trying to assume that a technology will always be able to help us out of our difficulties. But one of the things that I think that I know as an archeologist is that many past societies have gotten into trouble that their technology was unable to get them out of. We don't really know whether or not our technology will be able to help us out of the hole we're digging ourselves into. We can certainly hope that that's the case, but I wouldn't want to pin our futures just on that hope personally.

Marten Scheffer: So, you're mentioning people saying while people live in Phoenix and in Las Vegas and they do pretty well. Actually Las Vegas doesn't have such a high mean annual temperature, and neither does Phoenix. We're talking about ultra-places. You can live anywhere, of course if you have the means, if you have a well isolated house, powerful air conditioning, when you fly in your food, there is no problem to live wherever, even in that great heat. But if you have to earn a living working on the land, working outside, doing labor, then that is just not a possibility. So, people tend to have a strange perspective on heat. They think that Las Vegas is a hot place. While it can be much hotter than that. And they seem to think “what's the problem? I have air co, I have food,” but that that is not the situation that the vast majority of the people have that would be exposed to those very hot temperatures.

Michael Garfield: That's a good point. You mentioned in this paper that something like 50% of today's global population are small holder farmers or depend on small holder farming, and this is outdoor work. So, I guess at least one of those innovations would have to be like a dune stillsuit or something that you can…

Marten Scheffer: Yeah, everything is possible, if you have to resources, everything is possible. But most people just don't have to resources.

Tim Kohler:   Well, and the other trap is in thinking that we can always use technology to get ourselves out of these difficulties. And of course, air conditioning, at least the kinds we have available right now, flying in food, or other means of transporting food, all of these things take a lot of energy, and under present technology released a lot of greenhouse gases into the atmosphere, ultimately making the problem even worse. So, when we use energy-intensive ways to try to get ourselves out of these problems through some kind of adaptation, in the long run, we're digging ourselves into a deeper hole.

Michael Garfield:  Yeah, it's funny, the air conditioner is sort of a perfect example of this tragedy of the commons failure to coordinate. On that note, I didn't actually intend to discuss this paper today, but there is a fascinating paper that Tim just coauthored with Jaeweon Shin, Michael Price at SFI, David Wolpert at SFI, Hajime Shimao at SFI, Brendan Tracy, also. There's a lot of Santa Fe Institute on this one, but it's a paper about the Seshat DataBank that Peter Turchin and his people have put together, and a cut into it…a bit of exploration about the history of social evolution. And I'd like to hear you kind of lay out what you found in this study, and then let's turn it around and look at what light it might shed on this paper about the human climate niche moving forward.

Tim Kohler: Well in the first place, our paper was stimulated by a very interesting paper that Peter Turchin and his group published about two years ago in Proceedings of the National Academy of Sciences. And in that, they mined the Seshat DataBank as it existed a couple of years ago to try to look at the processes that move societies from very small scale –– as in say early Neolithic societies thousands of years ago –– to the sorts of apparently more complex societies that we see in the early States of France or England, or the early States of Mesopotamia. Can we see whether there are shared processes involved? And so, they had something like 50 different variables that they thought might be involved in this process that they were monitoring in their data bank. They grouped those into nine characteristics that they call “Complexity Characteristics,” and they did a principal component analysis. And they showed that the first principal component, that is the shared variance, across all these societies as they moved from small to large, was extremely high. 77% of the variants were shared among all these different societies. And these differences included things like: the capital population grew, the territories of the polities grew, the total population of the parties grew, the writing systems became more complex, the systems in which economic transactions were monitored became more complex, and on and on across nine different characteristics, more levels in the government, and more levels in the religion, and things like that. So that was a fairly stunning result. And David and I and other members of his group decided we'd like to look at this more closely, so we did. What we found is that there's another pattern in, there in addition to that which Peter Turchin and his group saw, that in no way invalidates what they did.

But the second principle component, in fact, shows that this apparently monolithic process of social, political evolution can be resolved into something like three different phases. In a first phase we see that polities or societies are concentrating on increasing in scale, mostly in population, but also in territory size. Once they get up to a particular scale, then they bump up against a boundary in which they cannot easily grow more in scale until they have improved their ways of processing information and processing economic transactions. And we call that a sort of information threshold. So, once they get up to the scale threshold, then they have to solve an information problem. And in the second phase of social evolution, there are multiple different pathways that societies explore for increasing their efficiency in their power and the information content of the ways in which they monitor transactions and govern and store information.

Once those problems have been solved, they come into a third phase of social evolution, which is again, predominantly a growth in scale. And we see this primarily only in the old world and the formation of big empires in the old world. So, does this have any ramifications? Can we build any intuitions from any of this as to what might happen in the future? Well that wasn't the point of that paper, but one thing does come to mind right away, and that is that we have radically improved our capacities for information processing in the last two or three decades. We now have marvelous cyber infrastructure that allows us to store, monitor and mine vast amounts of information. Does this mean that we are on the threshold of another sort of revolution in terms of growth in scale? In fact, I think we're already there. We're already embarking on that, and I'd like to point to something Marten said just a moment ago, that that growth in scale seems at this point to have been largely in the domain of private companies. Commercial firms, places like Google –– well you know the companies as well as I do –– those have really profited from literally from this growth in scale and they've become much more powerful actors on the world scene than any previous corporation has ever been. And where that will take us is an interesting question.

Michael Garfield: You know, I wonder if there's a different way to read this and you're the one to ask living online as I must for this job, it seems like so much of the conversation that I encounter is about polarization, fragmentation, the disintegration of the social graph. I talked about this with David and one of the transmission episodes regarding research by Miguel Fuentes, what we see at the cusp of a crisis, you know, that we see people Balkanize and seek out local solutions. And I'm curious in your study of archeological history, there was always another society over there, and now the story of global civilization is about changes happening within this planet, spanning structure or process. And so, when we talk about there being collective action problems, we pride ourselves on having gone through this information explosion. But the success of companies like Google hinge on their ability to help us sift and navigate and organize and make sense of all of that information. And I wonder if one of the things required in order to adapt, mitigate and migrate in a non-tragic way, in response to changes in global climate, might be better ways to coordinate ourselves as a planetary entity. And you know, we don't have a lot to go on as far as precedence in that regard.

Tim Kohler: What you're saying is that the cyber infrastructure has been built and is, at least to some extent, controlled, and made available to us by these huge multinational corporations, may allow us some opportunities, working largely from the bottom up, to coordinate our actions a little bit better. That's a very hopeful view of what could happen. One could also imagine that these companies or other powerful actors will find ways to influence the information that is available in these networks in such a way that people do not have full access to the information that they really ought to have despite the enormous reach of these media.

Michael Garfield: If we're going to dip back into the discussion of sunk costs to ask the economic equation that each of us has individually, and all of us collectively, are making as we pivot through the space of possible futures here…other than a massive uptick in extreme weather events, what sort of you catastrophes, to borrow a term from JRR Tolkien, do you imagine might lead to a more intelligent and preemptive response? What changes do you think might be possible here, Marten? I know that this paper on policy and large-scale behavioral tipping points touches on some of this, you know, the possibility of making a tipping point where none previously existed. Where do you think it's worth steering the inquiry –– not just through Google asks-->filter-->bubble manipulation of people's information as you just suggested, Tim –– but what might make this an easier calculation for people? One thought might be like Jessika Trancik’s work on the declining cost of batteries and electric vehicles. What else did the two of you see as bumping us off the “business as usual” trajectory into climate disaster?

Marten Scheffer: Well, that's a good question. If you want to change the world, change has to happen on many levels, simultaneously. So that same group that is brought together each year into Baltic by the Beijer Institute of Ecological Economics is actually working now on a paper on this question, and the consensus in the end is that we get to is there is no silver bullet thing.  What we will need is, first of all, this underlying increasing awareness that is destabilizing the status quo. People need to become more and more aware that we need to do things differently. But then also it has to happen. So that there can be those social norm tipping points, but it also has to translate to other levels. So, one level that is of interest is the level of the multinational organizations, whether they are point interested in making a move at some point, and what is needed for them to do that. What kind of things from national policies are needed to do that? What kind of pressure from consumers is needed to do that?

Then there is the view that bouncing back and forth little Twitter messages and Facebook connections doesn't get us to the depth of the discussion that we need. So maybe we need to have a more space for this elaboration. Maybe we need to get together for deeper discussion. And there are thoughts about how it is that kind thing can be organized. In general, you can think of different levels of levers on systems. The easiest ones are, well, let's just increase the minimum wage or just changing small parameters. The most profound one is changing the intent of the system. Where does it want to go? For instance, if you look now in Chile, there is a lot of social change going on. It was before the COVID crisis, I don't know if you noticed, but there were street protests, very big protests, millions in the streets. It was the whole country was flat. In fact, it was a bit like the Yellow Vests in Paris that people were just unhappy with the way things were going. It was mainly about inequality. It was triggered by the fact that people couldn't pay their electricity bills, their water bills, everything is privatized. Electricity, water is privatized, and they saw the people in charge of those companies leading very rich lives and they saw their retired parents being unable to pay the bills, so people became very angry. But then it changed in a very interesting direction. People started asking, okay, what kind of country do we want to live in? There were meetings in all the town halls, spontaneous meetings that everyone could set up, asking what kind of country do we want to live in?

The end of the story is that the constitution is going to be rewritten, and that's an anchor for a lot of change. It's not easy for a country to get a constitution rewritten, but you have to think about all those levels. The constitution was there because of the military dictature had changed the constitution in a way that would ensure continued power for the people that took the power. So, it's not like you can change something here and we will resolve everything. We have to change things, we have to think about change on different levels, and we have to find a synergy between those, if we want to speed up change…the change that is needed. There is not an easy action, not an easy silver bullet thing, but it all starts with a realization that we all are much better off if we force a change.  And then we pressure Milton nationals, we pressure governments, we change our constitution, we change our behavior. That kind of broad sweeping change is needed. And I think things like our paper may help people realize that something big is coming, and we need to change big if we want to avoid that.

And it happens to come in a time of the COVID crisis, where people are suddenly changing all kinds of things at very high economic costs across the whole world. I think we are seeing that yes, that is possible. It's not that we are inevitably locked into the way we always did things. It's very clear now that that is not the case. We can change. We can change rapidly and profoundly, even if that has a short-term economic cost.

Tim Kohler: That's a good place to stop, in my opinion. It was very nicely said.

Michael Garfield: So be it, yeah. I really want to thank the both of you for taking the time to talk today.