The Invention of Agriculture

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After 200,000 years of hunting and gathering, a history-defining decision was made. Starting roughly 12,000 years ago, at least seven different groups of humans independently began to settle down and begin farming. In so doing, they planted the seeds for modern civilization. This is traditionally told as a straightforward story of human progress. After humans made the switch, population growth increased, spurring innovative and creative endeavors that our ancestors couldn’t even imagine.

One counterintuitive strain of thought has treated this decision as “the worst mistake in the history of the human race,” as the popular author Jared Diamond once put it. The argument largely rests on research that shows our nomadic forebears were healthier and had more leisure time than those who chose to farm. Diamond, who wrote this article in 1987, when overpopulation concerns were rampant within the American environmental movement, argued that, “forced to choose between limiting population or trying to increase food production, we chose the latter and ended up with starvation, warfare, and tyranny.”

Sometimes unorthodox ideas are unorthodox for a reason. On today’s episode of Good on Paper, I’m joined by Andrea Matranga, an economist whose recent paper “The Ant and the Grasshopper: Seasonality and the Invention of Agriculture” argues that the Neolithic revolution happened as a result of climactic changes that necessitated storing food for the winter. Matranga rejects the idea that the past 12,000 years of human development were a mistake, one that underrates the threats of famine and starvation endemic to nomadic life.

“There’s a sense in which theories of the Neolithic tend to mirror the political anxieties and the social anxieties of the time in which people came up with them and in which they found favor,” Matranga tells me. “So, you know, obviously in the ’80s—WWF, environmentalism, Earth Day—people are worried about runaway population growth. So obviously in the Neolithic, they must also have had runaway population growth. There’s this interesting mix of the current events bleeding into history.”

The following is a transcript of the episode:

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Jerusalem Demsas: One of Aesop’s Fables is called “The Ant and the Grasshopper.” As the story goes, a hungry grasshopper comes up to a group of ants in the wintertime and asks them for some food to eat. They are shocked and ask him why he hasn’t stored anything up before the weather got cold. And he replies that he’d eaten well during the summer and made music while the weather was warm. The moral of the story is pretty straightforward: Save while times are good.

But for most of human history, for 200,000 years, humanity was much more like the grasshopper than the ants. As hunter-gatherers, we ate well when resources were plentiful but didn’t save for winter, making us susceptible to starvation and death.

But then something changed. Around the world, within a relatively short period of time, a bunch of humans independently began farming—and kept farming. How did this happen?

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My name’s Jerusalem Demsas. I’m a staff writer here at The Atlantic, and this is Good on Paper. It’s a policy show that questions what we really know about popular narratives.

In a paper called “The Ant and the Grasshopper: Seasonality and the Invention of Agriculture,” economist Andrea Matranga formalizes a theory for how humans went from grasshoppers to ants—for how we went from hunting and gathering to settled farming.

Climate seasonality increased, meaning winters got harsher and summers got drier. Hunter-gatherers couldn’t keep up with wildlife that fled for warmer climates. Birds can fly south for winters. Humans can’t. So they realized they needed to start storing food during good times. That meant the end of our nomadic lifestyles because people had to remain near those stores.

This paper intervenes in the literature in a couple of important ways I explored with Andrea: First, it helps untangle the mystery of how humans became farmers to begin with. But second, it pushes back against the strangely nostalgic idea that our nomadic existence was somehow better than farming—an idea that holds sway among a surprising number of people.

Let’s dive in.

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Demsas: Andrea, welcome to the show.

Andrea Matranga: Thank you so much. Thank you for having me.

Demsas: Yeah. So we’re here to talk about a very fun new paper that you’ve recently published at [The Quarterly Journal of Economics], and it’s about the Neolithic Revolution. We’re trying to go all the way back in time. We’ve done some development episodes, but this is further back than I think we’ve ever, ever gone.

I want to start with what the Neolithic Revolution was. Can you set the stage for us?

Matranga: Yes, absolutely. Neolithic means “new stone,” and it was first detected as a change in the shape of the stone tools that they were using. And then, eventually, they realized that the reason they changed the shape of the tools was also because they changed the subsistence method, meaning that before that—in the Paleolithic, in the Old Stone Age—everybody was a hunter-gatherer, meaning that they were subsisting on foods that grew wild, which they would collect, process, and consume. And then in the Neolithic, or New Stone Age, they started to grow their own food. So the origins of agriculture is what distinguishes the paleo from the Neolithic.

Demsas: And around how long ago are we talking?

Matranga: It was about 11,500 years ago in the Middle East. And there were seven of these places, and the two latest ones were in sub-Saharan Africa and in eastern North America, where it was about 4,500 years ago.

Demsas: You’ve just laid out the span of a few thousand years here where, in a bunch of different places across the world, people are independently inventing farming and agriculture. You said in sub-Saharan Africa but also in the Middle East, north and south China, the Andes, Mexico, North America. How do we know that these developments were independent? And what sorts of evidence do we have from archaeology or otherwise that signal when farming began?

Matranga: Yeah, absolutely. For some, it’s very easy. Obviously, if you look at eastern North America versus sub-Saharan Africa, these are two populations which had not had any cultural mixture, so clearly those two have to be independent.

When you go from, let’s say, south China and north China or the Middle East and sub-Saharan Africa, then it becomes a little bit murkier. Usually, the arguments that are made are that there’s no other signs of cultural contact, in the sense that the pottery styles are different; the crops that are being grown are different. Usually, you would expect that if they start doing barley and emmer wheat in the Middle East—if you thought that farmers had arrived with this knowledge of it into the Sahel region of Africa, you’d expect them to try to do some of those crops first, and then maybe they find some other crops that work better. And instead, it’s sort of completely disjoint. And that’s usually the way that they think about it.

Now, could it be that the idea that somebody was farming some distance away made their way through it? It’s possible, though one of the things is that there’s so many populations today, or in the recent past, that when they were contacted, they had knowledge of plant biology. So they understood perfectly well that if you plant a seed, a plant would grow. But they still hadn’t started farming. They were still hunting and gatherers. And so just knowing that it’s possible to do it doesn’t mean that you have a coherent sort of structure and a strategy for doing it as a population. So for example, I know that if you plant a seed, something grows, but that doesn’t mean I could sustain myself as a farmer.

Demsas: (Laughs.) Yes.

Matranga: So it still seems that, at least in the sort of making all the parts fit together, these things definitely happened independently in these places.

Demsas: But for most of human history, we’re talking about—I mean, 12,000 years ago is obviously a long time ago—but we’re talking about hundreds of thousands of years before then, where we’re a hunter-gathering and are nomads. And so this question of why we make this switch as a species is really, really interesting.

And before we get into your research, I’m hoping that we can talk through how the field was thinking about the advent of the Neolithic Revolution. And what were some of the prevailing theories about why agriculture emerged after the last Ice Age?

Matranga: Absolutely. So one of the things that happened was that, obviously, we didn’t have as many excavations done, let’s say, in 1900 as we have today. And we didn’t have as good, for example, DNA—we didn’t have DNA at all—but DNA sequencing and other stuff like that. We have much more tools. So obviously, then the theories have also kept pace with the new information that was uncovered.

If you look at the earliest theories—Darwin talks about this a little bit but also, let’s say, Braidwood—there are mainly theories about the Middle East because that one was the one where people knew that there had been a Neolithic transition. It was the first one to be excavated. And so most of the explanations are particular to the Middle East. And so one of the arguments that was made was that there might have been a climate desiccation, so it became drier around those years. And when it became drier, people were forced into these oases where there was still water. Therefore, once they were sort of constrained to these small areas, then it was easier to start farming and also necessary because there was just much less land that was fertile enough for hunting and gathering. And so you start taking better care about the land that you already have.

And then as you go forward, then one of the things that appeared in the 1960s was the fact that, actually, very often the hunter-gatherers seemed to live a life that seemed enviable in a certain way compared to farmers. And what I mean by that is that they didn’t work very long hours. They seemed that most of the time they only had to gather for a few hours a day. And, obviously, there’s an issue there, which is, What do you consider work? So is walking around hoping you’ll find something, but you don’t actually hunt—is that work? Or is it only while you’re actually chasing the animal? So that was one of the issues.

And then another issue is: When you’re a hunter-gatherer, the real problem you have is that it’s not so much about how much you eat during the average periods of times, but it’s what you do when things are very bad. And so for an anthropologist who happens to be there in a regular year, it looks like everything is great. But every 10 years, maybe, there’s a really bad year, and there’s a famine, and everybody’s starving. Now, if you don’t happen to be there in the year in which they’re having a famine, then you don’t understand why anybody would like to switch. That would be one of the caveats I would put to that hunter-gatherer issue.

And then we get to the 1980s. There was this very important book, very important also for my research, that was [by] Cohen and Armelagos. There was an edited volume from a conference in which they called hunter-gatherers the original affluent society, in the sense that what they find from many studies from many places around the world is that the farmers are actually shorter. The first farmers are shorter, much shorter, sometimes up to 10 centimeters shorter than the last hunter-gatherers. And basically, the first farmers, they get short, and they stay as short as subsistence farmers are to this day, while the hunter-gatherers—only in the last 50 to 100 years have a lot of people become as tall as the last hunter-gatherers.

Demsas: Mmm.

Matranga: And this was obviously very surprising to them. Basically, it was a continuation of this theory that perhaps it was better when we were hunter-gatherers. And then the question was: Why did they start farming if hunting and gathering was so great? And so there is this other article by Jared Diamond, and he called agriculture “the worst mistake in the history of the human race.” What he thought was it was runaway population growth.

And basically, what happens is that people think they know how the world works, so they start farming. And because you start farming, you become sedentary. And once you’re sedentary, you can have a lot more kids. Because if you’re nomadic, of course, if you have to carry your kids around, you’re going to naturally have to space out the births. And so once we become sedentary, we start having so many kids that, actually, we end up worse off than the way that we started. And what I think is interesting there is that there’s a sense in which theories of the Neolithic tend to mirror the political anxieties and the social anxieties of the time in which people came up with them and in which they found favor.

So, you know, obviously in the ’80s—WWF, environmentalism, Earth Day—people are worried about runaway population growth. So obviously, in the Neolithic, they must also have had runaway population growth. There’s this interesting mix of the current events bleeding into history, which you can also see with the Roman Empire. So everybody used to think it was because they debased the currency in the ’70s, because there was inflation in the U.S.

Demsas: And now it’s immigration. (Laughs.)

Matranga: Exactly. And now it’s immigration.

Demsas: It’s so surprising, all of a sudden.

Matranga: Exactly. So I sometimes tell students that there’s no such thing in history. There’s current events in period costume.

Demsas: (Laughs.)

Matranga: I’m exaggerating.

Demsas: It’s also a way in which our time period allows us to reflect on similarities with previous times. The Diamond one, I think, is particularly interesting. I was reading that 1987 paper. I looked it up. He was born in, like, the 1930s, so he’s in his 20s when the environmentalist and population-ethics concerns really take off. And it’s really striking. He writes, “Recent discoveries suggest that the adoption of agriculture, supposedly our most decisive step toward a better life, was in many ways a catastrophe from which we have never recovered. With agriculture came the gross social and sexual inequality, the disease and despotism, the curse of our existence.”

It’s one of those things—I think it’s useful to think through the ways that it’s possible that you may have made a very early mistake. Like, you maybe have reached an optimal point on a mountain, but you climbed a shorter mountain, and you have to go all the way back down to find a taller mountain.

But can you walk us through some of the evidence for seeing farming as a decline in living standards? Where is that coming from? I know you mentioned the height thing, but I remember reading there’s something also about increase in violence and other sorts of problems.

Matranga: Yes, absolutely. First of all, one of the things I want to just say to begin with is that it’s hard, for example, for things such as violence, in the sense that the selection pressure on archaeological remains from nomads is very different from the selection pressure for the remains of sedentary populations, simply because it’s a lot easier that remains from nomads might be very shallowly buried or not elaborately buried, while, instead, once you become settled, perhaps you have slightly more ornate tombs, which are easier to find, and other things that tend to preserve the remains.

Demsas: So we might be missing a bunch of information about the hunter-gatherer period.

Matranga: Yes, especially with things like child mortality. A lot of nomadic groups seem to not have considered kids fully humans, basically, until they were a few years old, just because the child mortality was so horrendously high, just through diseases and other things, that perhaps we have very different selective pressures.

But one of the other things that for sure we have is joint diseases. So it looks that the farmers were working more, because they tended to have more arthritis. And the joints on which they have arthritis are the ones that we would expect them to have if they were doing a lot of general farm work, digging, that sort of thing.

And also the grinding—the daily grind, right? It’s sort of an idiomatic expression because once you have these seeds—if I give you just, like, Oh, you’re hungry? Here’s a bag of unpopped popcorn.

Demsas: (Laughs.) Yeah.

Matranga: It’s like, What are you going to do with them? You have to put them on a rock and just grind them for hours and hours every day.

Demsas: I had no idea where the “daily grind” came from. I didn’t know that’s where it came from.

Matranga: Well, I didn’t until I said it.

Demsas: (Laughs.) So maybe you made it up. Okay.

Matranga: So maybe we can get one of the producers to check it. But it just came to me as I was saying it. I was like, Oh, I guess that’s where that’s from.

But to process that in an efficient way is also incredibly labor-intensive, and so their joint diseases reflect that, as well. And they also have something called porotic hyperostosis, which is, like—you get spongy bone tissue. And that is connected to anemia. So it looks like they were missing iron. And so these are some of the ways in which people have assumed that, basically, from almost everything that you could find, it looks like the farmers were actually eating less, on average, than the hunter-gatherers that came before them.

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Demsas: After the break: how the history of agriculture is actually a story about low construction costs.

[Break]

Demsas: So it’s in this backdrop that your research kind of comes in, right? People are assuming that it has to be a forced choice, because it’s obviously worse to have been a farmer than to be a hunter-gatherer.

But you have a paper that, I think, really explores and lays out a different way of thinking about things. Before you get into the meat of it, can you tell me about the genesis for the idea? What got you looking at seasonality as a predictor of the Neolithic Revolution?

Matranga: Absolutely. This is a little bit like that scene in Forrest Gump where he starts running, and he says, Well, I thought I’d run until the end of the street, and then I got to the end of the street, so I thought I’d just run into town. And 10 years later, he’s still running.

So the origin of this was that I visited my mom, and my mom was teaching Italian, as it was, at the University of Isfahan in Iran. And we went to see this ziggurat in Chogha Zanbil, which is one of those step pyramids. And I was trying to take a picture of this pyramid, and it was very hard to get a good contrast between the pyramid and the ground. And then what happened was I realized, Oh, of course, it’s hard because it’s made out of mud bricks. It’s made out of literally the same stuff that it’s sitting on. They compress it into bricks and dry them and then stack them, and that’s the pyramid.

And so then I was thinking, Well, why would agriculture originate from an area with very low construction costs? And so the idea was, Well, the reason why you would need low construction costs is because, once you farm, you’re going to get all of your food in one room at one point of the year after the harvest.

Demsas: And sorry—you’re saying that it was already established that farming had begun in places with low construction costs, or you came across this idea yourself?

Matranga: No. So the typical idea is: It starts here because it’s the Fertile Crescent, and it’s so fertile. And the problem with this theory is that the Fertile Crescent is very fertile if you compare it to, you know, the deserts north and south of it. But it’s not very fertile compared to any other place in the world. So it’s not very different in terms of the types of soil and the rainfall patterns than any other place, for example, on the north coast of the Mediterranean.

So the idea was: That’s why it started. That’s why it’s called the Fertile Crescent. And then I realized, Well, isn’t it weird that it happens to also be the place in the world with the lowest construction costs? Because it’s on an alluvial plain, so everything is clay that you can make mud bricks out of. And it doesn’t rain, so that means that it’s not gonna erode it, so you don’t have to bake the bricks, which takes a lot of energy. You just need to sun dry them, stack them, and that’s your building.

Then the idea was, Well, why would it be connected that you start agriculture, or at least it blossoms, in a place that has low construction cost? And I thought, One possibility is that they needed to defend their grain stores. So once you’ve harvested all this food, you’ve put it all in a room. Well, now that’s very attractive to any would-be thieves that would like to come and perhaps kill you and steal it. And that was my undergraduate thesis.

Then fast-forward a couple of years, and I’m doing a master’s, which later morphed into my Ph.D. at Universitat Pompeu Fabra in Barcelona. And I take this course with Hans-Joachim Voth, who later became my advisor, and it’s an Economic History course. And I tell him about what my undergraduate thesis was. And he tells me, It’s interesting, this idea of storage, because there’s this literature that says that hunter-gatherers were actually better off than farmers. And so it could be that maybe you can do some model where there’s some shocks from year to year, and having the granary helps you smooth out the consumption. And so the granary is also important for this reason. See what you can do with it. And I wrote a little paper for the course, and that was that.

From there, then the question was if this is just proof of concept that one of the advantages, that it could be when you start farming, is that you’re able to smooth your consumption. And so that’s why you accept a lower average standard of living, but you don’t get killed by famines when they happen every 10 years or so.

Demsas: It’s like insurance. You, as a human, are like, Okay, I’ll accept less food now, but I know I won’t starve in some forthcoming year.

Matranga: Exactly. And at that point, the story was still about variation from year to year, so I’m worried about famines. And a while after that, I came upon this paper by a French anthropologist called Alain Testart, and what this paper was about—it wasn’t really about farming. It was more about hunter-gatherers that become sedentary. And this happens.

Usually, we associate hunting and gathering with being nomadic, because you’re chasing the game around, or you’re moving up and down the mountains, depending on the seasons. And he said this isn’t really always the case. There’s many cases around the world of hunter-gatherers who are sedentary and have remained sedentary for centuries and millennia without progressing to agriculture.

And a classical example of this are the Native American cultures of the Pacific Northwest. And so there they exploited the salmon run. And so there’s all these millions and millions of salmons that want to reach their breeding grounds in the upland streams. And to do that, they have to pass through these rivers. And the Native Americans, they had these elaborate traps with which they capture the sustainably large, but sustainable—obviously, they wanted to let some through so that they’d reproduce a number of salmon. They’d skin them, and they’d smoke them, and they’d dry them. And that way, they had stores of food that would last them until the next salmon run, which is in the fall.

And he said, If you look at these groups, they have very hierarchical societies. They have elaborate material cultures. And so they had almost everything that we would associate with a farming community except the farming itself. Of course, the reason why they didn’t develop farming was because—it’s important, you know. The salmon is just a salmon. It’s gonna lay the eggs where it wants, and then it’s gonna go into the sea and live in the North Pacific for a few years, and then it’s gonna come back. That was an example of nomads which became sedentary and remain sedentary for hundreds and thousands of years without having farming.

And he said, And what’s crucial is that there’s food which is abundant and seasonal. And that was, like, my aha moment, because we take this story about sedentary hunter-gatherers, and then we could say, Maybe this is the stepping stone between being a nomadic hunter-gatherer and being a sedentary farmer. Because there’s this chicken-and-egg problem. Because if you’re always moving around, then how can you learn how to farm? And instead, if you don’t know how to farm, then why would you become sedentary? Because all the food is moving away. The game is moving away. You’re exhausting your local area, the plants. Why wouldn’t you just move to some other place where there’s more food?

Demsas: And you’d need multiple seasons to figure out how to farm appropriately for your region.

Matranga: Exactly. And so the idea was, by taking this Testart paper, I could say they would become sedentary first because they want to store food. And once they are sedentary and they’re storing food, then they’re preadapted for discovering agriculture, because storing food and being sedentary are two things you need to know how to do if you’re going to be a farmer. So at least you figured out that part of it before. And you do this because you’re trying to avoid seasonality, as Testart said. And this is when I switched from, instead of the problem being a famine every 15 years or whatever, then the problem is this periodic, predictable famine, which happens every year, which we call winter.

And so in order to avoid all starving in winter, we can just sit in one place, gather all these abundant foods in the places where these exist, store them, and then we can process them and eat them as we go along throughout the year, and then the next year we can do the whole thing again. And it was funny because I found this paper—it was a friend of mine’s birthday, and I had to call her and tell her, I’m sorry, but I can’t come, because I found the paper that sort of unlocks everything for me. And I’m just too excited about it, and I wouldn’t be much company.

Demsas: Did she forgive you?

Matranga: Yes. I mean, she already knew. It was baked into the pie. You know, we’d known each other a while.

And so that’s when he moved from, you know, once-in-a-while famine to predictable scarcity, which is seasonality. And from there, then my next step was, why would it be in—because one of the things that’s been observed is that the Neolithic Revolution happens right after the end of the Ice Age. And so the traditional interpretation by a bunch of people was: The Ice Age ends. Before, it’s just too cold to farm in the Middle East, and so nobody was farming there. And then when the Ice Age ends, then there’s the right climate for farming. And then you can farm.

And there’s two issues here, I think. And one of them was that if the climate is really good for farming, then it could also be really good for hunting and gathering. There might also be more wild animals. There might also be more wild plants. So it’s not entirely clear to me that a better climate automatically makes things better for farming. So that would be my first point.

And the second point is that if all you needed was a warm climate, then why couldn’t you farm during the Ice Age but, like, a thousand miles south of where you farmed when the Ice Age ended? Because it’s not like it was a snowball Earth. If you went to the equator, you know, it was still warm. And so my idea was: What was missing during the Ice Age were locations that were really good in summer but really bad in winter, because the issue with the equator isn’t that it’s too warm. The problem is that it’s warm the whole year-round—

Demsas: Yeah, so you would never start farming.

Matranga: —and therefore you don’t need to store. And the important thing is you never become sedentary in order to store, which then leads you to not starting to farm. What happens when the Ice Age ends? Now, there’s places that first it was, let’s say, –20 [degrees] in the winter and –5 in the summer. So there is seasonality, but all of the seasonality is below freezing. So it doesn’t really matter. It’s just a frozen hellscape year-round.

Well, now, if you think that moves, you know, sort of parallel, both the summer and the winter become warmer. Now you’re going to have a winter which is like –5, which is really bad. But now in the summer, let’s say it’s plus-15. Sorry—this is Celsius. I should have prefaced that. And so, basically, what happens is that now the summer is quite good, while the winter is abysmal.

And the question is: How can we exploit these very good summer conditions without getting stuck here in the winter, or without all dying in the winter? And of course, if you’re a stork, then that’s really not a problem, right? You can fly. You can go to this really warm place in the summer, have your nest there, and then in the winter, you just go back to Africa, and that’s perfect. But if you’re humans, and you’re carrying kids with you, then obviously that’s not going to work.

And so you cannot migrate your way out of a Northern Hemisphere winter. So their solution was to store food. And so they say, We can move to these places first. During the summer, we gather all the food, and then we can store it and consume it throughout the long winter. And then the next summer, we do that again. And that was sort of, like, my first idea of why it happens right after the end of the Ice Age.

Demsas: Okay, so the theory is, basically: The Ice Age ends. There’s more seasonality, meaning that the difference between summer and winter increases, so you have these kind of highly variable seasons that we’re used to now. Then people are then incentivized to store, so that they can store food for the winter. And as they’re remaining stable, they discover farming in order to supplement their diets.

Matranga: Exactly. And so the basic idea is: Once you’re sedentary, then, you know, for sure, like—I mean, what is farming? Farming is you’re expending labor in order to increase the amount of food that the land produces. So farming is really on a spectrum. Because a very simple thing you could do is chase away grazing animals so that they don’t eat the fields that you’re going to need in order to get the seed from it during the harvest season. And so that’s, in a sense, farming because you’re expending labor just chasing away the animals, and perhaps then you fence them. And then the next thing you could do is say, Well, last year, a lot of this area was flooded. So I’m going to dig a drainage ditch. And this way, when it rains, you don’t have standing water. The crops don’t rot. And we’re going to have more food the next harvest season. And then you can start doing all of these little things, which, put together, then amount to farming.

But I’ll just go back for a second to the seasonality issue, because what I later found out was that, actually, according to this theory by Serbian physicist called Milanković, it’s actually increases in seasonality which make the Ice Age end. And so what happens is that Earth’s axis is tilted—and famously, this is what causes the seasons—but sometimes it’s more tilted, and sometimes it’s less tilted. And there’s also other variations in Earth’s orbital parameters, and these influence the amount of seasonality that you have in the Northern Hemisphere and in the Southern Hemisphere. And so it’s not really that it was just the end of the Ice Age which caused seasonality to increase, but really there was this big increase in seasonality, which caused the Ice Age to end and also caused the start of agriculture.

Demsas: I would expect that there would have been farming that could come in and out of vogue. I’m curious why we don’t see that in your findings.

Matranga: I completely think that farming probably happened on some hillside 70,000 years ago and on some other hillside 30,000 years ago and some other place 15,000 years ago. And, you know, what I find really interesting and important about farming isn’t so much the fact that they did it once. It’s the fact that it’s a model which is able of spreading.

If it was just something that happened once on one hillside and then stayed there—or perhaps, you know, like the salmon run in the Pacific Northwest—that’s a fantastic accomplishment by the population that does it, but it doesn’t transform the world. Because you cannot take those salmon, bring them to a river in Iowa, and then, you know, just replicate your community in some other place. What’s special about farming is that it does sort of spread, and that it does eventually occupy most of the landmass of the world. And so it’s sort of what I call a franchisable model. It’s not just something that works in one place. You can copy-paste it all over the place.

And so I think it probably happened on some hill, but that’s not super interesting. It would be super interesting, of course, from an anthropological aspect, to find that one hillside where it happened 30,000 years ago. But that didn’t change the history of the world, clearly.

I think, in order to have that, you have to have a wide area in which there’s a lot of seasonality so that when somebody invents, first, you know, storage and sedentarism and then agriculture, then they’re able to take this packet of seeds, bring it to another place, give it to their kids. Their kids can found a colony. Perhaps they displace the local population. Perhaps they intermarry with it, perhaps not a lot of people. You know, I’m sure all three happened in different places at different times. And then their kids can do it in another place, and so you can colonize other places with this technology, or other people can copy this technology and do it in other places. And in order to have this, I think you need both the seasonality but, also, it needs to be on a wide enough area that it’s instantly appealing to everybody because they think, This is just what we’ve been waiting for, a chance to not all starve every February.

Demsas: Hopefully you can unpack why it was such a dominant strategy, right? Because you write in your paper, “Our ancestors traded a risky but abundant lifestyle for a more stable but less prosperous one, driven by risk aversion, particularly among populations near subsistence levels.” And I would imagine that you would expect to see variation based on different populations’ risk tolerance and also desire to kind of smooth their consumption. And also, it seems like there’d be a real free rider problem. Like, nomads could just go around just attacking sedentary populations, taking their food, and moving on. So it’s interesting to me that it ended up being such a dominant strategy to stay put.

Matranga: Yeah, so in terms of, obviously, the risk of raids, I think that would go back to my undergraduate thesis of sort of the importance of having some way of defending. So the first places that do this are actually, like, these hillsides—Jarmo, for example, was an early one—that are very steep on all sides. And, you know, the point is that with that, you kind of need a very specific land conformation, where it’s just the right shape of a hill, and there’s water, and there’s fields close to it, and there’s a way to get from the fields to the hill. And, you know, how many hillsides like that can you find? So the convenient thing is: Once you invent fortifications, then you can build a wall, and so build your own quote-unquote hill in the middle of the fertile plain, which is what they do with sort of Mesopotamia.

So that’s one aspect to it. The other one is that some people remain nomadic for a very long time, usually because either it’s too cold, the growing season is too short, or otherwise the rainfall is too low, and so they’re not able to farm, and the only way that they can survive in a viable number of people is by constantly moving around. But what they usually do, at that point, is they become pastoralists.

One way of seeing this is that it’s not just a matter of risk aversion, because in the end, if your risk aversion, high or low that it is—let’s say that you’re a complete nervous Nellie. You don’t want to take any risk, and you just eat grubs from under a stone, because you never want to leave your immediate area. Well, you’re probably not going to reproduce very fast, which means that either some neighbors that accepted a little bit more risk and have much higher average amount of food have more kids than you, and they can displace you, or even if you somehow intermarry with them, probably they’re not gonna accept your viewpoint on risk aversion. So the risk aversion, in the end, is something which leads you to make some choices, and these choices have some effects on the viability of your group.

Demsas: Yeah. I feel like the fertility question is really interesting here because it’s both that once you begin farming, you have to send your kids out to go farm themselves, but it increases the number of children that are born, too, that survive?

Matranga: I would say both. When you’re walking, when you’re nomadic, in principle, you cannot have more than one kid per parent, because somebody has to carry them, at least when they are, you know, below 6—because 6-year-olds can walk, but they can’t walk as fast as grown-ups.

The second aspect of this is that there’s so many diseases where if you could just stay in a place that’s warm for a couple of weeks, the kid would be fine. But if you’re in the middle of your migration, that’s it.

And the other thing is that when you’re constantly breastfeeding and moving around, you’re probably not gonna put on a lot of weight. And it would appear that a lot of hunter-gatherer women would take a few years to even be fertile again. Because they just would not achieve that—I forget if it’s 15 or 18 percent or—whatever the number is of body fat where your body can even conceive.

So absolutely, when you become sedentary, you can have more kids. And I think even if you want to remain nomadic, if there’s these farmers which are having way more kids than you survive, then if there’s ever any conflict—maybe now, maybe in two centuries—then very likely, the farmers are going to get their way.

Demsas: I’m curious about us returning to what you started this conversation with, which is the question about whether or not it was a good idea for us to move out of the hunter-gatherer stage to the farming stage. Because your paper has something to say, also, about whether we’re over-reading the evidence about humans being worse off nutritionally when they become farmers. So what’s your pushback on this question about, Maybe nutrition was actually improved once you become a farmer?

Matranga: Yes, absolutely. It’s interesting because the first concrete evidence of anything that I found in support of my thesis was what I’m about to tell you. And it’s something called “Harris lines.” So Harris was a pathologist. I believe that one of his kids had a pretty severe disease. For some reason, he saw an X-ray of his kid, and he noticed that he had this line in their bones, sort of a transverse line. So, you know, like, not in the direction of the bone—kind of like a tree ring along the growth.

And so then he explored this more, and he found out that when there is an episode of growth arrest of a child that is growing normally, then—for example, this could be a disease, or it could be that you’re not eating—and so there’s what’s called a “metabolic insult.” Your metabolism is not producing enough energy to both keep you alive while growing, and so then you have growth arrest.

And then when you start eating well again, or the disease passes, then there’s something called catch-up growth. So the body actually grows faster, because it’s trying to get back on the growth curve that it was on originally. And as it’s growing faster, it deposits this different kind of bone, which you can see from X-rays. And so it’s a little bit like a tree ring, but for mammals.

And the interesting thing is that from that same Cohen and Armelagos 1984 book, Paleopathology at the Origins of Agriculture, it also looks like the hunter-gatherers had—they were taller, up to 10 centimeters taller, but they also had—way more of these Harris lines, or growth-arrest lines, in their bones, sometimes as many as six per individual, on average, in some populations. And they also appeared to be evenly spaced, just like tree rings. And so to them, this suggested that almost every year, there would be a period of famine.

And so it really looks like it was this insurance trade-off that you mentioned before, which is that, you know: The hunter-gatherers, they ate a lot, but for a few months, at least, every year, it looks like they were starving, while the farmers, they ate less, on average, but they always ate. They were able to smooth their consumption from summer to winter, logically.

And I think that one of the reasons this had not been proposed before was because as sedentary people with bank accounts and granaries, you know, usually our problems are not about, like, I’m eating a lot this week, but what am I going to eat next week? But if you are a nomad, and you’re not able to store food, then that, I think, would be the dominant concern, and I think that’s why we accepted this trade-off. Like, Sure, we’re just going to be shorter. That’s fine. But, you know, at least we don’t starve for a couple of months every year.

Demsas: So you think this is the correct trade-off? You don’t buy the thesis that we made a mistake?

Matranga: No, no. I think we did a great trade-off. In fact, I think that part of the problem with, even, development goals—they tend to be phrased in terms of averages. We would like people to make, at least, $5 or $10 a day, on average, throughout the year. And then how can we get them to invest? Or how can we take them to become entrepreneurial and so on? But when you’re this close to starvation, I think that the average, obviously, you think about it, as well. But what you’re really worried about is, What am I going to eat in the worst possible case that could happen to me within the next 30 years?

Because the way that they survived as a population through the centuries was by taking the worst case into possibility. If I take a statistic of a country, and I measure their income every year, and for 25 years, it’s quite good, and then they all die in the 26th year, the average income is still very good, but that’s a complete disaster for the population involved.

And so if anything, I think that our way of measuring success is, again, predicated on the fact that we do have insurance, and we do have bank accounts, and we do have granaries. And so our worries are more about averages, while if you are a hunter-gatherer, your life is dominated by the worst outcome. And I think it was a correct choice. In fact, it was so correct that we forgot how awful it is to be eating a whole wildebeest that you killed and still be worried about what you’re going to eat next week.

Demsas: Well, Andrea, always our final question: What is something that you thought was a good idea at the time but ended up only being good on paper?

Matranga: As a personal anecdote, I’d spent a lot of time figuring out a good way to move to the U.S. And I loved my time in the U.S., but then I realized that moving continents is very difficult when you still have family back home. And the things that you like and that you think you’re going to enjoy when you’re 25 and don’t have kids, then once you have a family, you have to move backwards and forwards and all the summer stuff, then it starts to wear on you.

So I just realized, after being incredibly internationally minded, I still love traveling and visiting places, but I became much more homeward bound in my aspirations as time went by.

Demsas: Yeah. Well, Andrea, thank you so much for coming on the show.

Matranga: Absolutely. My absolute pleasure. Anytime.

[Music]

Demsas: Good on Paper is produced by Jinae West. It was edited by Dave Shaw, fact-checked by Ena Alvarado, and engineered by Erica Huang. Our theme music is composed by Rob Smierciak. Claudine Ebeid is the executive producer of Atlantic audio. Andrea Valdez is our managing editor.

And hey, if you like what you’re hearing, please leave us a rating and review on Apple Podcasts.

I’m Jerusalem Demsas, and we’ll see you next week.

[Music]

Matranga: So it was funny, because if you had asked me, What would you say is good on paper? And I was ready to say, Well, for all my office and copier paper needs, I use Dunder Mifflin, the paper supplier. But the setup—

Demsas: The setup was too different? You were going to go with Dunder Mifflin? That’s so funny.