Overview

We and our tools together form a giant network, a swarm. It exists because we’re born defenseless but with big brains. Lacking claws and fangs, to get food we need both tools and each other. We’ve organized ourselves around those facts since our species began. Despite walking upright, making tools, and talking, we long did what nearly all other animals did—we roamed the earth to gather our food. Then, just a few millennia ago, some of us started to farm. That then triggered many new tools. They then triggered many changes in our swarm. But, likely, we didn’t intend any of that. Our swarm can fall into certain styles of organization simply because that’s how certain kinds of complex networks link themselves over time.

This chapter shows how we came to change our food gathering over the millennia. We turned into farmers because as the last ice age ended, our swarm entered a feedback cycle called ‘autocatalysis.’ As that spread, our swarm rearranged its structure in a process called ‘phase change.’ Those two kinds of ‘swarm physics’ behaviors have shaped us from then to now. They’ll continue to shape us in the future. For instance, although none of us planned it, we’re now halfway to becoming an urban species.

Autocatalytic Runaway

There must have been a lot of bickering back then. It’s 11,600 years ago and, although we don’t know it, our world is about to end. The problem is lunch, and how to get it. That’s not so easy now that the ice age is ending. The earth is warming and as global climate shifts, so do herd migration patterns. In the wind-swept hills of what is today northern Iraq, one of our arguing bands is nearing a golden field of long-stemmed grass. Perhaps we haven’t sighted a gazelle or wild ass herd in many days. Or maybe we’d herded a few goats but disease killed them. What to do? Keep walking and starve to death? Or make camp and starve to death? That’s why we’re bickering. We’re all at least decided on one thing: We’re so hungry that we’re ready to eat grass.

As we enter the field, one of us, perhaps a woman, wonders if the grass seeds clustered on the waving stalks are good to eat. Squatting to pull some up, she finds that they come off in her hand, as if meant to be easily harvested. We then gather several lapfuls of seeds. That night we make unleavened bread, like today’s tortillas or chapatis. We pound the wild seeds to a pulp, mix with water, and lather the paste on a flat rock near the fire. That night, painted by the warm firelight, our band forms a tableau, a freeze-frame of our species before the fast-forward changes to come. Perhaps months (years? centuries?) later, we figure out how to ferment the same grass seeds. Now we have beer. We don’t, however, give up hunting and gathering to become bread-eating, beer-swilling hicks. Foraging is what we know. It’s kept our lineage alive for at least 1.8 million years. So we keep roaming, following our food.

But our band keeps returning to the field of wild wheat. Then one day, for whatever reason, instead of discarding our brushwood huts and moving on as always, we build a more sturdy camp of mud-and-stone. We still don’t settle; but our band keeps returning to the camp seasonally as game dries up elsewhere. We also don’t plant anything for centuries. Perhaps the idea didn’t occur to us, but it’s just as likely that we simply had no need.

Now it’s 300 or so years after our first mud-and-stone huts. We still haven’t tamed the wild grasses near our camp, but we’re starting to store their seeds. About then, in Dhra’, southeast of the Dead Sea in today’s Jordan, some of us build a settlement. We make our huts with the same mud and stone as before, but this time we also build a granary. It’s a special mud hut with a raised floor to protect against mice and moisture. There we store our new treasure—seeds. We build it outside our other huts, but surrounded by them. A further 700 or so years go by at Dhra’ and now we no longer share our grain store. (Or perhaps we now have much more grain to store?) Many huts now have their own built-in granaries. Around 90 of us now live together at Dhra’. We’re stepping into a trap, but it’s a trap we can’t see.

It’s now about a thousand years after the ice age ended and we still hunt and gather, but our old wanderer ways are fading away. Now another of our early settlements, Shanidar Cave in northern Iraq, gells. Soon, about 150 of us live there. That number may be the final turning point for us, because it’s perhaps six times more than foraging alone could feed. What was once a small band of 25 or so wanderers had grown into a clan, then a small village. Our band’s numbers have now risen beyond the level that we could support by hunting and gathering alone. That’s the nexus at which everything starts to change for our species. That’s when we begin to become something truly alien.

But, likely, none of us planned any of that. To see why, look again at those wild wheat seeds on their stalks. As they ripen, their stalks shatter and they fall to the ground, to sprout. The stalks of a few mutant plants, though, fail to shatter. Normally that strain would be rare—it can’t make new plants—but 11,000 or so years ago hungry humans were roving nearby. We ignored the wheat stalks that had done the right thing and shattered. Picking up their scattered seeds would take more energy than eating them would give. But the few mutant plants still had their ripe seeds on the stalk. That left them in the perfect position for us to harvest them. Then, after a thousand years or so, we started planting some of the mutant seeds we didn’t eat. That gave those mutants an edge over their normal cousins, so they spread. That then led to our first big change—and all our big changes since then. With that, not just settlement but farming itself began.

All that likely happened starting around 11,600 years ago, when the last ice age ended. Perhaps the global warming made no real difference for many of us around the world, but for some of us in the mountainous grassland zone from Israel to Iran, maybe it did. That seems plausible because we had first started settling about 14,000 years ago, when the planet had briefly warmed, but gave it up once the ice came back. Then, once the ice age finally ended, our species went on to tame rice, beans, squash, and yams—in southern China, northern India, north-central Africa, and central America.

Today we still live with the genetic changes that we started back then. For example, we first tamed maize in Mexico’s central highlands perhaps 9,000 years ago. Early on, those wild corn cobs were less than half an inch long. But, as the millennia passed, we kept selecting bigger cobs. By 1492 some cobs were already six inches long. Today, some are 18 inches long. Without our help, such mutant maize plants would quickly die out. Their kernels couldn’t escape the cob to sprout. It’s the same for many of today’s egg-laying hens. Over generations, we’ve selected them both to produce a lot of eggs and to not brood them (sit on them). So normally their eggs wouldn’t hatch. If we died out, so would they. So too would our cows. If we weren’t here, they’d stop being fat and placid, their numbers would plummet, and the few that are left would go feral. Over time, they would turn back to something like their ancestors—wiry aurochs. Poodle numbers would crash too, and any survivors would grow back into something like gray wolves. Watermelons also would shrink back into small, bitter berries. Today’s sheep and apples and rice, and all our other tamed animals and plants, are all products of the same uncontrolled, 11,000-year-long genetic experiment. They’re all made things. All are technology.

As soon as we started to farm, our food became technology. ‘Technology’ doesn’t merely mean something shiny you can buy in a store. Dirt roads are technology too. So is butter. So are shoes and chopsticks. So is a toilet, a sewage system, sewing, buttons, and chewing gum. Much of how we organize ourselves is also technology. An installment plan is technology. So is a pension plan, a bank, a stock exchange. Even in the wilderness we make technology. Stacking stones into a cairn to cover a dead body is technology. Building a dam is technology. So is kindling a fire. We make all those things to serve our needs, and they wouldn’t exist without us. Most things surrounding us are technology, or the results of technology. We eat technology. We sleep on technology. We live in technology. Technology is what we do.

And that’s why we’ve changed so much since we started both settling down and farming. Before then, we all lived in small roving bands. Our food didn’t stay put, so neither did we. Since we could walk only so fast, and since the earth could produce only so much per acre, we had to limit our numbers to about 25 or so in any one band. That’s about as many of us as could live together. All that changed once as we settled.

For one thing, slavery became more likely. When we were all mobile we likely weren’t meek—we could maim and kill just as well as anyone else could—but we likely didn’t take slaves. There’d have been no point. Back then, each new mouth might have meant having to add about 80 acres to our food-gathering range. So capturing someone to darn your socks would have made zero sense. (Not to mention that you didn’t have socks.) But once we started turning into farmers, new hands became worth more than their new mouths. As farmers, we also had more work to do. So slavery would have started making sense. Slavers could now both feed slaves and force them to make more food than they ate. Also, once we were stuck in place, we could invest in more permanent things—like slave pens. Even herders can’t stop slaves from running away as cheaply as farmers can. Then once we had long-distance trade, slavery would have made even more sense. Before the horse, the camel, the ship, as slaves we could just run away. Our ex-captors could only follow on foot.

But, for many reasons, farming’s biggest change was what it did to our numbers. First, as today’s female athletes and dancers know, lowering body fat lowers female fertility. Ovulation slows or even stops. Thus, hunter-gatherer women bear few children. But as our food supply increased, female body fat grew more uniform throughout the year. Ovulation regularized. Birth rate rose. It rose for another reason too. Hunter-gatherer mothers have to carry their infants, so they suckle them more since infants are always close to the breast. Breast feeding releases hormones that reduce fertility. But once we settled, we no longer had to carry our babies all the time. That in turn reduced suckling. That then raised our birth rate. Settlement raised our birth rate for yet another reason. Once we no longer had to carry our kids around all the time, women could have more than one at a time. Plus, farming made an extra pair of hands, enslaved or not, worth more than an extra mouth. Thus, as we turned into farmers the cost of kids relative to their future labor value fell. Women, instead of reproducing every three to four years, turned into yearly baby machines. We multiplied like rats in a grain silo.

That kind of self-feeding cycle isn’t unique to us. Chemists might call it an autocatalytic (‘self-stimulating’) reaction. A catalyst is anything that stimulates a chemical reaction while remaining unchanged. An autocatalytic chemical reaction thus helps itself continue—it makes its own catalyst. The more the cycle goes on, the more catalyst it makes, which helps the cycle go on, which then makes more catalyst. It’s a beast whose hunger rises the more it eats.

Something like that began happening to a few of us 11 millennia ago. The more mutant plants we ate, the more of us there would be to ensure yet more mutant plants. We’re thus as much a part of our mutant plants’ reproductive system as they are of ours. So just as we selected mutant families of crops, so too must they have selected mutant families of humans. But most human genes take between 50 and 100 millennia to spread widely. So, in terms of genes, our species hasn’t changed much since we began farming. There hasn’t been enough time. Yet because of all our new tools we’ve changed everything around us, and that’s changed how we must live. Thus we’ve changed our food, but our food has also autocatalytically changed us.

Changing Phase

Autocatalysis isn’t the only network mechanism that pulls us together into a swarm. It helps explain why we started to farm, but not why we kept at it for 10,000 years. Some termite lineages have farmed fungus for 50 million years, but not one of our ancestral species—going back millions of years—were farmers. So, unlike termites, farming is for us very recent. Why did we stick with it?

As rovers 11 millennia ago, we each had to carry about 20 pounds of food, weapons, tools, and babies. Anyone truly sick, or maybe even just lame, simply died. We couldn’t stay to nurse them for long because to stop moving was to starve. On the other hand, we were rich in many ways. We didn’t have much, but then we also didn’t need much. We had plenty of spare time and our dogs may have helped with the hunt. We were also hardy from unceasing exercise. Plus, we had few diseases—there weren’t enough of us in one place for them to persist. We were thus tall and slim and fit and healthy. All of us in a band were related, and, likely, all of us, including children, were armed. Also, likely, none of us were slaves, and, likely, all of us had a say in what we did next.

In short, back then we weren’t naked apes with heavy jawlines hefting stone axes and grunting at each other. When you’re on foot, weight is the enemy. So we likely didn’t make most of our tools with stone. Stone is simply the thing that survives longest, so shaped stones from that time are the main relics we find today. Instead, we probably made grass shoes, leather bags, and string baby slings. We almost surely also made bolos and bows, tents and watergourds, drugs and medicines, plus clothes, ornaments, tattoos, chewing gum. Even 11 millennia ago our toolbase was already well-developed. After millions of years of fine-tuning, it was well adapted to our needs. Even so, only about four million of us were alive at the time. Our toolbase couldn’t support any more than that.

Today, we number in the billions and, as of 2007, half of us live in cities—with over a million more of us moving to cities every week. Today, nearly all of us live on farmed food, so we think of farming as natural. But it isn’t. Skeletons from 10,400 years ago help explain why. Buried in the shifting sands of Abu Hureyra, on the banks of the Euphrates in today’s northern Syria, they speak of females in pain. They had enlarged and often injured toe joints, curved and buttressed femurs, enlarged knees, and damaged, or even crushed, spinal disks. They must have had to kneel to grind nuts and grain. With only stone grinders and sweat, it must have taken them hours to grind enough flour for just one family meal. Adolescent skeletons also speak of regular and excessive strain. They must have had to carry heavy loads on their heads daily. And everyone—girls and boys, men and women—also had fractured teeth. Likely, that came from eating partially ground grain and bits of stone flaked off during the grinding.

Millennia later we would write that “In the sweat of thy face shalt thou eat bread, till thou return unto the ground.” So why didn’t we give up the new farming fad and go back to foraging? Perhaps many of us did, but after farming for a while most of us couldn’t. We were already too many. For instance, in Abu Hureyra we’d originally sited our village on a gazelle migration path. For a while the pickings must have been good. We grew fat. With autocatalysis, our birth rate spiked. But as the planet kept warming, the herds declined below the level needed to support us. Oops. Nurturing mutant grain then became more and more important. The shtick that had worked for our lineage for nearly two million years quit working.

So we invented new tools. By about 9,000 years ago in Abu Hureyra, weaving had already become a speciality among a few women. Fewer fractured teeth overall suggest that we then figured out how to weave sieves fine enough to sift our flour. Then, as the Syrian climate dried further, the gazelles vanished entirely. We then tamed sheep and goats. We also stepped up our planting. Then we figured out how to hand-throw clay pots—perhaps we’d noticed that pots were good ways to store grain against rats. We may have then made more pots to soak our grain and cook it into porridge because our fractured teeth then disappeared. Those of us with few or no teeth could now survive. Before, we simply died. However, with our new soft foods, tooth decay, once rare, grew. Also, with no more teeth-breaking, our numbers grew. But our larger numbers also helped diseases persist. They could now circulate for decades without dying out. They could even move back and forth between us and our newly tamed food animals. So we got sicker. Infant deaths then climbed. In this way, each solution to a problem led to a new problem, and thus yet more tools.

We invented all those new tools, but we couldn’t have intended their effects. What hunter-gatherer 11,000 years ago would have interrupted the campfire songs to say: “Let’s farm! Sure, we’ll lose about five or six inches in height. We’ll be sickly too. We’ll get less protein, we’ll eat too much starch, and we’ll have less variety in our diet. Plus we’ll have to work much harder. We’ll also have to work all day long, we’ll invent slavery, more women will die in childbirth, and more of our babies will die. We’ll also be in great pain for thousands of years. But we’ll just have to bear it so that our remote descendants can have mobile phones.”

Millennia ago, we couldn’t have foreseen our present lives. Even if we could, we wouldn’t have wanted them. Even if we had, our changes happened too slowly for us to notice them. So we aren’t half-urban today because we planned to be. Instead, we fell into our present, trapped in an autocatalytic food cycle that we began when we first started farming. Once that cycle got going, our growing toolbase then changed us permanently. But why?

Take another look at the difference between rovers and farmers. About a thousand farmers can live on the same land that 25 foragers need. If it ever came to war, those legions of sickly, gap-toothed farmers would wipe out the few healthy nomads. Even when the tall rovers won, the hordes of runty farmers that they would then rule would simply swallow them, as a pond swallows a flung pebble. A few centuries later, the ripples would have died down and it would be much the same as if they’d lost. We’d farm mostly the same foods. We’d make about as many babies. We’d be able to feed about as many priests and warriors—although they might serve different gods and have different weapons. Life would go on much as it had before, except that we’d have changed some of our names and customs. So whether the rovers won or lost would have made no real difference.

That’s just what happened to hunter-gatherers in central Europe 7,500 years ago, when the first farmers swept through from the south. Those farmers fathered most of today’s European population. The forager way of life vanished, as did most of the original foragers. It’s also what happened to the Amorites in Sumeria over 4,000 years ago. They didn’t build houses, or plant grain, and they ate raw meat, but they were good warriors. They came with their flocks down from the hills surrounding Sumeria and took over. Life must have been good for them, for a while. But over time they had to turn into farmers, just like the folks they now ruled. Same story for the Hyksos in Egypt 3,700 years ago. Same for the Vikings in Europe 1,200 years ago. The Turks in Persia, the Mughals in India, the Mongols in China, the Bantu in Africa—whether they came afoot, on horse, or by ship, the farm swallowed them all.

In brief, become a farmer and you must stay a farmer. And anyone not a farmer who tries to make you stop being a farmer must also become a farmer. As rovers, if we wanted to stay nomadic, we had to kill all the farmers. Our only other choice was to become herders and trade with them—or to flee. Even if we did nothing at all, every generation there’d be yet more farmers crowding our land. Farming is the roach motel of human life—we can check in, but we can’t check out.

As with autocatalysis, that process isn’t intentional. It’s a network mechanism. Nor is is even special to our swarm. Physicists might call it a phase change. Water, for example, has several phases. In its liquid phase it won’t expand to fill a room, it will dissolve sugar but not rubber, and so on. But all those properties change as it freezes into ice or boils into steam. The advent of farming shows that we too can phase change. As a species, we’re stable if we’re all in one phase or the other—either rovers or settlers. When we’re a mix though, rovers feel network pressure to settle. It doesn’t matter whether we like it. It’s irrelevant whether we planned it. It’s unimportant if we even notice it. In time, most of us will phase change into farming.

In sum, we didn’t choose farming. It chose us. We didn’t start to build our current half-urban world 11 millennia through some plan. Farming isn’t ‘better’ than foraging. Farmers weren’t taller, healthier, better fed, or more relaxed than foragers. On the other hand, foraging isn’t ‘better’ than farming, either. Farmers can have things that foragers can’t. But foragers also can have things that farmers can’t. Farming yields more food per acre of land, but foraging yields more food per hour of labor. Settlement, followed by farming, may have first occurred because it was the only choice for a few of our bands during some stressful time. Perhaps all our other bands in the same position died. Autocatalysis then took over. Once that happened to enough of our bands in enough places, network effects then amplified its spread until we phase changed into grass-eating all over the planet. We didn’t decide to do that. In some sense, our swarm did.

Eat Your Heart Out

By about five millennia ago many of us around the globe had turned into farmers. We then began a way of life that’s still the norm for about half of us today. For all that time we’ve been trying to make our food supply larger and more reliable. Some of our biggest changes, however, have happened only in our last few centuries. Before then, peasant diet varied with the region and the season, however, in Europe, just to choose one case, our staples were, and still are, cereal grasses: wheat, barley, oats, rye. We made them into bread or porridge. We also fermented them, or various fruits, to make ale or cider. To those we added peas and beans, turnips and cabbages, leeks and onions, and honey. That’s what most of us ate and drank most of the time.

For an idea of the times, here are some prices from around 1300 in England. Two dozen eggs cost a penny, two hens cost thruppence, and two geese, five pence. A sheep cost one shilling and tuppence (that is, 14 pence). A hog cost three shillings and four pence. Two gallons of ale cost a penny, but a gallon of wine cost four pence—as did a pair of shoes. Four pence was also the yearly rent on an acre of land. A brass pot cost over a pound (20 shillings). Anything that needed fuel and special tools to make was expensive. Further, in good times, two bushels of wheat cost five pence. After a big storm, though, that much wheat could cost four shillings. In a famine, it could cost five shillings. But an experienced carpenter earned only tuppence a day. A laborer took two days to earn thruppence. A maid took a week to earn one penny. And at least a third of the population was held in bondage. A slave and his family sold for 13 shillings and four pence, or about as a much as a cow—or a horse suited for military service.

In that world, most of us couldn’t afford much meat, if any. So most of our animal protein came from eggs, lard, or bacon drippings. Oxen and horses were more valuable for manure and plowing. Cows were for milk, butter, and cheese. The forest deer were for our manor lords. Kill one, and the lord’s foresters might blind, castrate, or hang you. Instead, as peasants we raised pigs. They can live on kitchen slops, forest beechnuts, and acorns. We built fishponds in the river, and we raised poultry—though not for the meat, but for the occasional egg. Men with swords or bibles took the rest. Much of our extra animal protein went to our lords temporal as tax and our lords spiritual as tithe.

As peasants, we built all our meals around the staff of life, bread. But wheaten bread was for our rich; the rest of us ate bread made from beans, oats, and other grains. Mold was always a problem. Soft breads wouldn’t keep, so we often baked them into bricks. We didn’t eat them—we gnawed them. The toothless ate porridge. We salted what we could, but salt was so dear that we sometimes used it as money. We also had fresh fruit and vegetables, but only in summer. It was the same for dairy products, except for a little hard cheese and perhaps some salted butter. Plus, not all our animals could survive winter because we couldn’t feed all of them for all that time. We, too, needed food to survive winter. So at year’s end, we killed most of our livestock and smoked or salted the meat.

Thus each year we had to solve hard math problems. A cow, for instance, was hugely important. It was a milk source. It was also a lot of meat on the hoof. Its flops were also a cheap fuel source and building material. In a pinch, it could pull the plow if the oxen died. It was also a source of manure for the fallow fields—and thus future hay, and so future cows. So we had to balance our yearly cow-killing against the amount of fodder that we could gather and store before the autumn rains spoiled the hay. Kill too many, and we might starve next year. But kill too few, and again we might starve next year. Similarly, our children were valuable because by the age of seven or so, we could put them to work. On the other hand, they needed food. Each year we had to figure out how many kids we could afford, and how many cows we must slaughter. Each year, we walked a tightrope, and sometimes we fell off, as happened to Europe in 1314.

That year, Europe fell into a Great Famine lasting seven years. Climate change triggered a cold snap, and the cold and rain destroyed crops and killed both our food animals and draft animals. The poor among us, which was about nine-tenths of us, ate diseased cattle, pets, rats, insects. We ate the leaves off trees. We ate grass. Then all hope died and we began to eat each other. Millions of us died. That famine and bad weather then worsened Europe’s Hundred Years’ War. All three then worsened Europe’s first visit from the Black Death. Millions more of us died. But while that was extreme, it was hardly surprising. Widespread famines had come to Europe just before (in 1257-9), and would come just after (in 1346-7). Just in the 50 years before 1314, England alone had suffered famine roughly every 11 years. That pattern had held for at least the last thousand years. Nor was our famine cycle special to Europe. In Africa, India, and China we suffered just as much and just as often. Famine, then war, then pestilence; it was a familiar cycle—everywhere.

Even without famine, most of us in Europe back then went hungry twice a year—in the spring, after winter stocks were gone, then in July, the month before harvest. A failed harvest didn’t always mean famine, but it always at least meant widespread hunger. First we foraged for beechnuts, berries, and nettles. Then we ate our older farm animals. Then we ate our future by eating all the rest. When those were gone, we phase-changed back into foragers, roaming the land, hunting food. We then risked death to poach eels from millponds, and squirrels, rabbits, and birds from the lord’s forest. If caught, we might be hanged—if the wolves or bears or wild boars didn’t get us first. Granaries were our banks during such lean times, and mold, weevils, and rodents were our eternal enemies.

Food wasn’t our only problem though. In Europe at least, damp and cold killed us just as casually as hunger did. The poorest of us lived in small, dark, smoky huts. We built them with poles daubed with clay, cow dung, and brush. We roofed them with thatch and covered their earthen floors with straw. We had no chimneys and no windows. At around five feet tall, we were short and bent. Our skin, like a cured ham, was leathery from our household smoke. By 30 we were nearly toothless and many of us didn’t live to see 35. Dirty and rank, we lived with our livestock and knew everything about lice, fleas, and dung—and nothing about microbes. One in four of us died before we were a year old. And all of us were always working. We tended the fires, the livestock, the fields. We made food, thread, cloth. We repaired clothes, bedding, cottages. In any scraps of time left over, we sewed or carved something to trade. Our skeletons from that time show the effects of all that toil—extensive osteoarthritis, spinal deformations, bony growths, and joint enlargements. When we were foragers, to stop walking was to die. Once we were farmers, to stop working was to die.

Of course, our lives weren’t always that hard. Most of us lived low off the land—with meat and cheese and even wheaten bread rare—but we were used to it. So, most of the time, we managed to stave off outright hunger. When we made just the right number of kids, and we slaughtered just the right number of our food animals, and the weather behaved, we even feasted. Slaughtering an ox might feed an entire village. Also, not all of us were equally poor. The richest peasant family in a village might own a couple of oxen, a bullock, two horses, some cows and calves, a pig and sow, a hundred or so sheep, geese and chickens, and maybe even a cart. In their house, they might have as many as five brass pots and pans, plus a jug and basin, a trestle-table, and maybe even a chair. Also, a very few of us were ladies in funny hats or knights in shiny armor, and we always lived well. But the risks were always there, for all the rest of us. Over nine-tenths of us were rural, and roughly a third to two-fifths of us not only had no food surplus, we didn’t even have access to enough land to give us all the grain we needed to survive. We had to earn the rest with non-farm labor.

For millennia, and all over the globe, our species lived that way. Then, starting only a couple centuries ago, a fifth of us left that hungry world. Soon, another fifth will likely do so. Instead of constantly asking ‘When next can we eat?,’ some of us started asking today’s big three imponderables: Why are we here? Where are we headed? Do these clothes make me look fat?

That was a phase change just as big as the one that dragged us into farming in the first place. How did it happen? That will take some time to explain but Balzac put one popular story about it this way: “The secret of great wealth is a forgotten crime.” It’s a good story. Our rich can indeed steal. Our poor have indeed been stolen from. For instance, in the late nineteenth century, Belgians caused the deaths of at least eight million Congolese and stole literally tons of ivory and rubber. Our rich have really good housebreaking tools—inside information, numbered Swiss bank accounts, tanks. But that can’t be the main reason why so many of us are fat today. No amount of theft among ourselves can explain the difference in our lives between 1314 and today. All theft can do is rearrange who has what stuff. It can’t make more stuff. Most of what we have today we stole from the universe itself.

No other animal species can do that. Gazelles, for instance, always have a carrying capacity; that is, some limit to how much their numbers can rise before dying back. That’s true for us too, but we’re nowhere near our limit because we invent things and we trade things. So there’s no fixed limit to our food. Even something as seemingly simple as our invention of pots changed our food supply. With them, we could store more food than we could before. Whenever we make an important new tool—the pot, the plow, the tin can, the train—we can use it to make or store or move more food. That works for many of our non-material tools too: banks, credit systems, pension plans. Each of our new tools pushes down our food-to-tool exchange rate. Gazelles can’t do that.

Further, the periods during which that exchange rate stayed fixed—once millennia, then centuries, then decades, and perhaps one day, years—are shortening. That’s happening because beyond a certain point we fell into a new autocatalytic cycle—an industrial one. Once we had a critical mass of tools, the more we had, the more new food we could make (or store, or move). The more food we had, the more of us there could be. The more of us there were, the faster our toolbase could grow. In some parts of the globe today, our tool supply is now growing faster than our numbers can. Hence, some of us now worry about being too fat rather than too thin.

In short, ever since most of us became farmers about five millennia ago we’ve been building a worldwide food machine. All our calamities, self-inflicted or otherwise, are merely blips on a long networking project. In many ways we’re just like termites building a nest, except that ours covers a whole planet. But if that’s so, how come we usually don’t see ourselves and our food supply that way? Well, until a couple centuries ago, big increases in our food supply used to be rare. Most of the time it really was mostly fixed. Thus, the only way for me to get more food was to kill you—or steal from you. Hence the Belgian sack of the Congo, among many others. That then led to the belief, popular especially among our rich today, that we have a carrying capacity, as gazelles do. More of us—often a codephrase for more of us who’re poor—are just a bigger drain on our resources. Sooner or later we starve back to our carrying capacity. In the short run, that must be true. In the long run, though, it makes no sense. Unlike gazelles, we can, and do, change our limits. We make new tools, and we trade what we have. To survive, and even prosper, we bind ourselves to each other via our tools and our trade. We thus act together like a composite being, a swarm. In that swarm we expand our planet-wide nest and invent our way out of hunger. We needn’t make our nest wittingly, nor need we make it because we’re peaceful, selfless, caring, or farseeing. We do it because we can and because it benefits us. Trade is the glue that binds us all, and our wit is the weapon we use to carve a place for ourselves on this planet. So the secret of most great wealth isn’t a forgotten crime, but a forgotten technology.

Many of us today don’t see ourselves that way, just as those of us in fourteenth-century Europe didn’t see ourselves that way. Back then, we lived in a hungry world. Travel was so slow and costly that our manors there had to be largely self-sufficient. When hard times came we had nothing to do but starve—or make someone else starve. Today, many of us, especially in our richest nations, have forgotten that past. We thus preach personal, familial, corporate, and national self-reliance, just as Europe’s manor lords once did. It’s a wonderfully bracing fiction—the frontier life, rugged individuals, everyone for themselves. But in practice, and with rare Robinson Crusoe exceptions, we’ve never been self-reliant. We’ve always banded together. It’s our awareness of, empathy for, and network linkage to each other that distinguishes us from the beasts that perish. We live by each other’s grace.

Seeds of the Future

Today, just as in times past, it’s common to assume that we’ve now reached the pinnacle in our food supply. That belief is common in our poor lands, where we can’t imagine how it could be different, but it’s just as common in our rich lands, where we feel little pressure for change. Everywhere, we today often assume that our food production is now both efficient and unalterable. It’s neither.

For instance, suppose a carrot plant is growing at the equator. Of all the solar energy it’s exposed to, it uses less than one percent. It’s worry isn’t how to extract more energy from the sun, but how to extract more carbon dioxide from the air. Without carbon dioxide, it can’t make carbohydrates, which means it can’t grow. But there’s only a trace amount of carbon dioxide in the air. So of what little solar energy that carrot plant captures, it uses about half just to transpire water from its leaves. That’s how it keeps its sap flowing upward, which is how it extracts water and minerals from the earth. It also needs energy to respire water to keep itself cool. Thus its problem isn’t too little energy—it’s too much energy. So it throws away over 99 percent of the energy it gets from the sun.

We don’t do any better. We might eat only about one percent, or less, of the energy that carrot plant captured. That’s partly because we lose at least 30 to 40 percent of all our plants to weeds, pests, and disease. (For instance, we lose between a quarter and third of all our soybean, wheat, and cotton before harvest. We lose even more of our maize, rice, and potatoes.) Even after harvest, on average we throw away around 93 percent of our food plants as inedible. (Partly that’s because of spoilage—we lose around 40 percent of our cereals after harvest. It’s also partly because we don’t eat most of our plants—roots, stems, branches, leaves.) Of the remaining seven percent, we eat only about 13 percent. We even waste a lot of that. For example, in 1995 those of us in the United States threw away 27 percent (96 billion pounds) of our edible food. In 2007, Britain we threw away almost 15 billion pounds of our edible food. We then use much of the remaining energy to seed, nourish, protect, harvest, transport, prepare, package, and sell those edibles. In all, between our plants’ wastefulness and our wastefulness, when we eat a plant we’re failing to capture at least 99.99 percent of the energy that the plant originally got from the sun.

Nor is that the end of the waste. In 2005, those of us in the United States each ate about 200 pounds of meat. Further, those of us there fed over half of all the grain that we grew to our food animals. But if we feed a carrot plant to a rabbit, then eat some rabbit stew, we’re wasting a lot of energy. That’s because all animals, including rabbits, and ourselves, eat food only as soup. Stomachs break down food into a soup of tiny bits, then the rest of the body uses those bits for spare parts and energy. So when a chicken eats grain, then we eat a chicken sandwich, we’re eating something whose plant equivalent could have fed perhaps ten of us. When we eat seafood, often we’re wasting even more energy. For example, tuna eat herring, which eat zooplankton, which eat phytoplankton (tiny sea plants). Every stomach in the chain means a roughly ten-fold loss of energy. So when we eat some tuna salad, we’re forfeiting lots of energy. In short, when we eat any animal, our species loses at least 99.999 percent of all the energy that our planet originally got from the sun.

To compensate for all that waste, we add yet more energy. For instance, on the Canadian prairies an acre of wheat needs about 80 pounds of nitrogen fertilizer a year. So we inject into the earth about 1.6 million kilocalories of energy per acre per year. That’s not counting the cost of phosphorus, sulfur, and potassium fertilizer. Nor does it count the diesel fuel we burn for tillage and transport. Processing our food burns yet more energy. It costs three times as much energy to put a can of applesauce on a grocery shelf as it does to put the same amount of apples in the produce department. It takes 15 times as much energy to make a bag of potato chips as it does to make an equal amount of potatoes.

Look at it this way: A pound of rice is about 18,000 grains. For every 5.5 pounds of rice the sun gives us, we end up eating only about one grain. And getting that single grain takes many of our tools, much of our energy supply, plus the year-round effort of about half of our species.

If we’re to change any of that we must first change how we think about plants. We get about 80 percent of all our nutrition from them, but they aren’t good at feeding us efficiently. What they’re good at it is making more of themselves. A plant is a self-building factory. It sucks in air, water, minerals, and sunlight and extrudes parts. It builds a structural shell (its stem) and inside that it builds pipes, filters, and hydraulic pumps (its vascular bundles). It builds storage bins (its roots), and solar cells and gas exchangers (its leaves). It also builds factory-embryos (its seeds, tubers, or spores), as a reproductive mechanism.

Many of those factory-embryos are rich in the building materials that future factories will need to start building themselves. A few of them—grains, legumes, nuts, tubers, and such—are big, easy to harvest, and easy to store. That makes them worth our while to eat—just as we eat chicken eggs, but don’t bother with chicken sperm. Sometimes though, we instead eat the factory’s solar cells, as in spinach and lettuce. Sometimes, as in celery and asparagus, we eat its shell and hydraulic system. We might also eat its storage system, as in carrots and radishes. Or we might eat its casing (sassafras and cinnamon). Or its hydraulic fluid (maple), its capsule casing (dandelion, nasturtium, pansy), or the whole thing (sprouts and mushrooms). (Although, a mushroom is a fungus, not a plant.) When we eat a plant, we’re really eating a factory.

Seeing plants as factories helps us see our farms anew. Today, we aid our little green factories by aerating their soil. We also raise their nitrogen, phosphorus, and potassium supplies. We raise and control their water supply. And we separate them so that they don’t have to compete for such supplies. So what we’re really doing when farming is manually injecting our cleverness into a plant’s lifecycle to get it to do what we want. In the future we might pack all those smarts into the plant’s seed itself.

For example, every plant on earth needs nitrogen to make its proteins and genes. We need it for the same reason. Unlike carbon dioxide, nitrogen is plentiful. It makes up 78 percent of the atmosphere, but most plants are such saps that they never figured out how to capture it from the air, even though they capture carbon dioxide from the air. They can only suck it in via their roots in the form of ammonia or nitrates in the soil. But those get made only rarely (fire, lightning, rock weathering). Plus, once made, they dissolve easily. So it’s lucky for plants that we animals concentrate nitrogen compounds in our bodies. Thus, to a plant, an animal is just a walking bag of nitrogen (and carbon dioxide). That’s why corpses, urine, and dung can make such good fertilizer. So when we fertilize a plant, we’re mainly giving it more nitrogen. But we may not need to do that forever.

For instance, legumes—like peas, soybean, and clover—long ago found a clever way out. They’re symbionts; that is, their roots make a home for nitrogen-fixing microbes. That then lets them make proteins. And that’s where we get most of our protein today. All around the world we make meals by pairing proteins with carbohydrates. If it’s not soy and rice, then it’s bean and maize. If it’s not lentil and potato, then it’s bangers and mash—or burger and fries. So one day we might remake our cereals to extract nitrogen as legumes do. If so, they’d no longer need nitrogen fertilizers.

As of 2005, new genetic editions of soybean, corn, cotton, canola, squash, and papaya, plus several others, already covered 141 million acres worldwide. Such smart seeds would change us, just as mutant grass seeds began changing us 11 millennia ago. For one thing, we’d need even fewer farmers. Our use of fertilizers, herbicides, insecticides, and fungicides would also fall. Also, more of the cost of farming would fall to the cost of the planting and harvesting machines, and the cost of the seeds. Those seeds, in turn, would cost more as they take more effort to debug and become more efficient at feeding us. Seed piracy would also grow since the biggest cost would then become that of designing the seeds in the first place. Real estate prices would also change as smart seeds change the meaning of the word ‘arable.’ We would also, no doubt, make many mistakes—we might even cover the planet in a new superweed, like today’s kudzu. Engineered plants are just as shameless as any other plant. They’re all hussies and will happily mate with their older and wilder cousins out in the bush, creating all sorts of hybrids. But if that doesn’t destroy us, much of the planet’s biomass might then turn itself into our food.

The Food Factory

Our seeds will likely get smarter over time, but that’s unlikely to mean the end of our millennia-long search for more reliable food. However smart our seeds, our farms are, by far, our biggest water drinkers—and our biggest water wasters. We are mostly just walking bags of water—globules of the oceans as they existed perhaps half a billion years ago. Our body, and most of our food, averages about 65 to 75 percent water by weight. (Apples are about 84 percent water. Mushrooms are about 90 percent water. Lettuce is about 96 percent water. An apple pie, a hamburger, and a pizza are each about half water.) So when we grow food we’re mainly making tasty water. (Which our stomachs then turn into soup....) But that tasty water is expensive. Each of us drinks about a gallon of water a day, yet the food we eat that same day could have needed up to 1,250 times as much water a day to grow. A pound of wheat needs 120 gallons of water to grow. A pound of rice, 144. Growing the ingredients for a simple loaf of bread may need more than two tons of water. Eating animals consumes even more water. For instance, raising a lamb for six months may cost over 22,000 tons of water. So when New Zealand exports a lamb cutlet to a desert nation like Saudi Arabia, what it’s mostly exporting is lots of water.

Of all the water our species uses, we use ten percent at home and 20 percent in industry. Our farms gulp 70 percent. Plus, both homes and industry return up to 90 percent of water used. Farms return only 30 percent. Most of the rest simply evaporates. In India and China, irrigation alone counts for over 80 percent of all water used. In parts of India, China, and the United States, we’re consuming groundwater faster than it can replenish itself. Water tables are steadily falling. Our water consumption rose six-fold during the twentieth century. That’s more than twice as fast as our numbers grew. Today, over a billion of us around the world lack access to safe drinking water. Thus, often when you buy a farm today, mostly you aren’t buying land. You’re buying water rights with some land attached.

Our farms are also, by far, the biggest modifier of the planet. Across the globe, we now give 4.4 billion acres to our crops, and 8.1 billion acres to our livestock. That’s about two-fifths of all available land area on earth. We’re now losing about 15 million acres of primary forest a year. We’re also now losing about 4.7 tons of topsoil per acre per year. Our farming, on both land and sea, also destroys millions of species. For instance, nine-tenths of all big predatory fish—including tuna, cod, and halibut—have vanished from the continental shelves just since 1950. The earth is having a gigantic fire sale, where, apparently, everything must go. Except us. Maybe.

Will any of that ever change?

Predicting the future of food is even harder than that of farming alone. It’s hard to step out of our place in time and distinguish between a thing and its function. Take your refrigerator. It might look like it mainly keeps your foodstuffs cold, but really it mainly keeps them fresh. Today we use cold to do that, but any device that slowed decay would do. However, such a change would have to wait until we better understand the proteins that make our food.

All living things on earth are mostly made of the same stuff as a carrot cake. A sperm whale, a bowl of petunias (minus the bowl), Diana Ross and the Supremes, we’re all bags of just a few elements. The big four are: oxygen, carbon, hydrogen, and nitrogen. We’re also made of a little phosphorus, potassium, sulfur, and such. (That why those seven are the chief components of fertilizer.) But to feed ourselves we can’t simply down a bucket of carbon and inhale a cubic foot of hydrogen. We need the stuff in particular structures. Glucose, for instance, is one such structure. It’s made of carbon, hydrogen, and oxygen. Our body digests it by converting it into other structures of the same three elements. Arrange the elements one way and you get albumin. (It’s the chief protein in egg whites.) Arrange them another way and you get urea. (It’s the chief component of urine.) All of us animals are just machines that can convert eggs into urine.

That conversion happens inside our cells. A cell, like a plant, is a self-building factory. To build itself, it needs specialist molecules, especially proteins. Its genes specify its proteins, but it’s the proteins that actually do things. They build things, break things, move things, signal things, notice things. Long strands of them also wind together to make muscles. Thus, about half our body’s dry weight is protein. (That’s why nitrogen, which makes up a big part of all proteins, is so important.) We’ve now figured out lists of genes and their related proteins for the cells in a couple hundred lifeforms, from microbes to fruit flies to us. But to make sense of a lifeform we also need to know what all those proteins do. To figure that out we first have to do a lot of cross-checking. A protein may work one way in fruit flies and another in us—although it’s often the same. Once we know what all a cell’s proteins do, we could start replacing one gene with another. In turn, that’s important because a cell makes whatever its genes tell it to make. So if we change its genes we can change what it does. Thus—if we knew what we’re doing—we could tell a microbe how to eat plastics, thus making our plastics self-disposing. We could also engineer a microbe that cleans up oil spills. Or one that clears arteries. Or one that makes steaks.

Making a steak isn’t hard—if you’re a cow. But we haven’t yet figured out how to do it without a cow. it’s hard to tease apart the effects of thousands of proteins working in giant catalytic networks in the cell. It’s a bit like crashing a big party and identifying circles of friends by seeing who talks to whom, then watching each circle to see who gossips most, and what the topics are. (Well, it’s not really that easy. For example, topics can change depending on nearby topics; but you get the idea.) And we now have a tool that simplifies all that cross-checking—the computer. The next problem is that of making a life-support system for our synthetic genes to copy themselves in. Once that’s solved, we might make many foods in vats.

Mere science fiction, you scoff? Well, yes. But we’ve already redesigned many microbes. We’ve remade some to build wholly synthetic proteins. We’ve built viruses from scratch. We’ve changed cells to build themselves simple digital circuits. We’ve even made cells that eat sugar and excrete diesel oil. There’s no reason we couldn’t one day fool cow cells into making a hunk of cow—without a cow. In essence, a cow is a walking fermentation vat that turns grass into cow muscles, which we then slice up into steaks. Do we really need the cow? Could a vat do as well?

Nor need that only happen in some future-shock world full of fembots and flying cars. If such food factories were to come to exist, most of us needn’t even notice them. We might continue to buy our food in grocery stores and markets. It’s just that the store would get some of its food from a factory rather than a farm. Sounds unlikely? That’s already happened. Quorn, for example, is a cheap fake meat made from vats of fungus. It’s been available for about 30 years already. And we’re already planning to make vat-grown pork from pig stem cells. But we don’t yet know what we’re doing so if such meat-sheets were to go on sale today, they’d cost over $1,000 U.S. a pound. One day though that price might drop to $1 U.S. a pound. If so, food builders might then hop from factories to stores. Limited use in rich homes would then be just a question of time. The word ‘homemade’ would then gain a whole new meaning.

We need to feed ourselves, yes, but do do we need to expend quite so much energy, water, and land—and extinguish so many species—as we do now? Once upon a time we invented pots to protect grain from rats. Then we found that we could also use them to make porridge. (Or perhaps it happened the other way around.) Once we did, our teeth-breaking ended and our food stores grew. Today we’re beginning to think that we might soon extrude potatoes instead of grow potatoes. Why not? Our fridges might then stop being food-storers. They could become food-makers. As a byproduct, they might make oxygen, as house plants do. Such food machines might even go into our spaceships. Dirt farmers may become increasingly weird throwbacks. Perhaps they’ll grow only the bulk plant-products we need for fibers, fabrics, paper, rubber, spices, and livestock feed. But even they could use the new machines to make such things. If that’s our future, our whole farming industry—from dairies to rubber plantations to fisheries—might well go away. Half our species would then be free to do something other than farm or starve to death.

Future Tense

We’ve changed our food supply a lot over the millennia, and especially during our last century. But our changes likely aren’t over yet. Since you’re reading this, you’re rich enough not to die of hunger today. But, as of 2006, about 17,000 of our children around the world will. Today, over 920 million of us are hungry. We also still have famine today—it’s just rarer. Plus it mainly only affects our poorest families within our poorest countries. But even in our richest countries, where there’s more than enough for everyone to eat, our poorest can still sometimes starve without enough money—or a gun. And in the half-minute it took you to read this paragraph, six more of our children will have died of hunger-related causes.

Why?

Today, worldwide, the average adult human male consumes about 2,700 kilocalories of food energy a day. (An adult female consumes about 2,000.) That’s about the same amount of energy that we’d get by burning a pound of coal, which today costs about five cents U.S. Yet, today, feeding ourselves costs far more than that both in money and risk to our future. Must it always do so? Must we continue to walk a food tightrope? Must we continue to destroy so many species while doing so? Must our poorest continue to starve to death? Nothing in the laws of physics decrees that.

However, physics isn’t the only thing that matters. First off, even if food machines were to come to exist, they still wouldn’t mean food utopia. For one thing, as partly digital devices, they could crash. They could also be hacked. Also, even though they might live in kitchens and not gardens, as food sources they’d still have pests. Mice and roaches and microbes would still be hungry.

Further, were such devices to come to exist, they’d bring wrenching change in the short run. Our present food producers likely wouldn’t like that. They’d fight that possible future, just as foragers fought farmers in the long ago. The whole food handling, processing, and distribution business would probably also panic. Likely, they’d fight against any change, perhaps taking to the streets to warn us against the new horror of frankenfoods. Food consumers, which is all of us, would also probably be rigid with fear. Many of us are going to oppose any change in something as vital as food. So politics, not science, would decide whether food machines might become widespread. It would be entirely irrelevant that we’ve been eating frankenfoods for thousands of years.

Also, in countries with good distribution networks, economies of scale may well work against home food machines. After all, they do just that today for water and power. Few of us have our own wells or generators; it’s often far cheaper to centralize production and distribute its results. So economics, not engineering, would decide whether our future food machines might become more like power stations or more like washing machines.

Yet further, legal and perhaps even military needs would also matter. For example, food snobs would continue to pay huge sums for expensive, hand-grown food. Elites would continue to eat salted fish eggs laid only in special rivers. And connoisseurs would continue to drink hand-made fermented grape juice grown only in specially blessed earth. None of them will want their foods tainted with anything machine-made. Also, were food machines to come to exist, someone, somewhere, would hack one. They might then use it to make homemade cannabis, mescaline, heroin—or gunpowder, gelignite, nerve gas. What might it be like when you can make cocaine in the kitchen? A food machine would really be a disguised organic matter converter. It needn’t only make food. Even were we to use it only to make food, for a select few that food might be—who knows?—human flesh. Presumably, clientele for such products would be quite exclusive. Were any of that to happen, it would scare lots of us.

So despite our climbing numbers, our growing cities, and our wasteful and destructive farms, a food machine might still take us many decades to make. That is, if we ever make one at all. A meat product that today costs $1,000 a pound but that one day may cost $1 a pound, has little chance to come to exist in a world where beef costs less than $3 a pound in our rich countries.

Although we’re likely to most need food machines in our poor countries we’re most likely to create them in our rich ones. And what’s the economic incentive? Today, food is a nearly negligible cost for our rich, but it’s still a huge cost for our poor. For example, average food cost for those of us in the United States is now around ten percent of income. For those of us in Eritrea, it’s as much as 71 percent. If eating costs you ten cents on the dollar, and food prices double, you grumble. But if eating costs you 71 cents on the dollar, and food prices double, you starve. For instance, in 2007-2008, global food prices rose. In Britain, those of us there had to pay, on average, about ten percent more—around £ 750 a year—for our food. Many of us complained, but the added cost was small given our high incomes. In India, however, the same change meant that 40 million more of us there fell into poverty. Food riots in West Bengal followed. In all, that food price rise meant that 75 million more of us went hungry. In short, those of us who most need food machines can’t afford to make them. And those of us who can, don’t care.

But wait, we all care about starving babies, don’t we? Well, we sure say we do—especially when we only ever see them on TV. But based on how we spend our money, our rich care far more about being too fat. For instance, in the United States today, around two-thirds of us are too fat. In Britain, about 60 percent of us are too fat. In Canada and Germany, at least half of us are too fat. All our rich countries are bloating. Meanwhile, about six in every ten of those of us who die each year die of hunger-related causes.

Those of us in our rich nations are too fat because we have cheap food, and we have cheap food there because we have a large and reliable food supply. We’ve built a huge toolbase to ensure that. It consists of costly machines, trained farmers, and extensive credit systems. Those support huge equipment purchase and training, and vast storage facilities and transport networks. Add to that many schools and research institutes. Also add fast, long-range data exchange, and a wealthy and stable—and literate—home market. However, those of us in our poor countries have little of that toolbase. We also have far less incentive to increase our food production. What’s the point? We couldn’t sell more of it abroad anyway. Rich countries won’t let us. Trade barriers shut out much foreign food.

For example, in 2006 our rich countries gave $372 billion U.S. in subsidies to their farmers. That’s over a billion dollars a day. The United States exports cotton far below cost. The European Union exports sugar far below cost. Japan marks up foreign rice so much that it costs between four and ten times more than local rice. Meanwhile, tens of millions of us in Benin, Burkina Faso, Chad, Mali, and Togo, are starving. Why? Those of us who are farmers there grow cotton, sugar, and rice. We work for some of the lowest wages in the world, yet still we can’t compete. Cotton subsidies alone cost us $250 million a year. In effect, our rich countries are paying their farmers to starve farmers in our poor countries.

In sum, the laws of physics aren’t likely to control whether or not we’ll ever have food machines. The laws of ‘swarm physics’ matter more. Thus, if we never get food machines it likely won’t be because we can’t use them, or can’t build them. More likely it will be because our rich countries don’t really want them. We’re thus likely to make mountains of expensive, empty food—fat-free, calorie-free, taste-free—long before we make any cheap, nutritious food.

That matters because today our swarm is in the midst of a vast phase change based on food. That phase change started a few centuries ago as we began to develop new machines, but it isn’t over yet. More change is likely coming because we’re now leaving our agrarian age and entering our urban age. Half of us now live in cities, and well over a billion of us now live without food fear. By 2015, another half-billion of us will likely have drawn ourselves up to that level of comfort. By 2030, our species may be almost two-thirds urban. By 2050, we may hit a peak population of roughly nine billion. For every three of us alive now there’ll be four of us by then. Most will be urban. So not only are our numbers rising, so are our incomes, and thus our food demands. Thus by around 2040 or so, food demand—and thus energy, water, and land demands—may peak. Large, long-term trends are converging on a point somewhere not too far in our future. We’re nearing a crisis point.

A storm is coming and we aren’t yet battening down the hatches, so more of us below decks are going to drown. Our rich are up top, enjoying the freshening breeze, while below decks our poor can’t see out the grimy portholes—and no one’s at the helm. However, we’ve already changed our food supply a lot. For example, in 1998 Eritrea was one of our poorest countries. By today’s standards, three in four of us there were undernourished—the highest figure in the world at the time. Yet Eritrea in 1998 got more kilocalories per person than France did in 1705. (At that time, the bulk of the French diet was vegetable soup with a little butter and little or no meat.) Similarly, India in 1998 ate better than Britain did in 1850. Today, about one in seven of us are starving, but in 1970 about one in four of us were. Since then, our proportion of poor has dropped, our average income has doubled, our infant deaths have halved. Over four in five of us in poor countries now have at least adequate diets. In our poor countries from 1961 to 1992, our numbers doubled, yet our per-person daily kilocalorie intake still jumped by a third. Even with all that though, we’re still straining our resources, given our inefficient and destructive farming.

So one day, perhaps this century, we’re likely to again change our food tech—or we may again face famine and cannibalism, even in the richest fifth of our planet. Perhaps we’ll run out of one of our presently cheap resources. Or maybe we’ll suffer overly abrupt climate change. Or perhaps one of our clever genetic trials will go awry. But even with our paltry computer tools today, we have a far better chance now than before of seeing our next food calamity coming. Europeans in 1314 had no warning before some of them had to rob graves and eat their dead. Our swarm is now much bigger and stronger than it was in 1314. Perhaps that will be enough to push us into making cheaper food sources before disaster is full upon us.

Or perhaps not. Maybe we’ll continue to ignore what’s likely ahead. Why not? We’ve done so many times before. Political unreality has often trumped scientific reality. For example, in China from 1958 to 1961, we let political insanity and bad weather kill 30 million of us. Things got so bad that villagers swapped their children with each other. No one wanted to have to kill and eat their own kids. As many of us died in China then as were alive in all of northern Europe in 1314.

However, despite our politics, food machines might still be in our future. After all, many of our recent tool changes have unwittingly reduced our uncertainty about our food supply. For example, a drought in northern China in 1877-8 killed between 9 and 13 million of us. Half a century later, famine came again. It was the most severe drought there in two centuries. Plus, our numbers had risen. Yet, despite our usual bickering and muddle, only three million of us died. The earlier famine showed that far worse was possible. What made the difference? The railroad and the telegraph. And neither originally had anything to do with famine. Similarly, the industrial phase change that gave us tractors had nothing to do with farming. As much as anything else, it started with an ironmonger trying to pump water out of Cornish tin mines. Our first tin can wasn’t made of tin—it was a champagne bottle. We got it when a Parisian cook found a new way to preserve fruits for his candy business. Our first fridge had nothing to do with preserving food. It started with a doctor trying to prevent malaria in Florida. Our first synthetic fertilizers fell out by mistake when a French chemist tried to make cheap diamonds, a Canadian inventor tried to make cheap aluminum, and two German dyers tried to extract gold more cheaply. None of them planned to make fertilizer.

We don’t intend everything that happens to us, but neither is our history simply a random sequence of events. Famine management is part of a vast wave of change going back 11 millennia. From the moment that one of us thought that certain grass seeds weren’t half bad when pounded and baked, we entered into a covenant with the soil. It hasn’t ended. Everyone whose hands have dug a carrot out of black earth knows that. That covenant cuts both ways though. Since the first ragged flint sickle tore through a sheaf of wild grass millennia ago we’ve shaped our plants and they’ve shaped us. Potters to make pots, pots to hold grain, granaries to hold pots, priests to bless them, raiders to pillage them, soldiers to guard them, metal for the soldier’s weapons, chariots for the raiders, healers for the injured, writers for the histories.... Each step set up the next. And each had a cost—often blood, sometimes genocide—but always fear and pain. We knew neither what we were doing, nor where we were going. We’re no different today. We’re always stumbling into our future, and mostly we’re looking at our sore feet, not the distant horizon. If we continue to do so, then at least 17,000 more of our children will continue to die of hunger-related causes today—and tomorrow—and the next day—and in the minute you took to read this paragraph, 12 more of our children will be dead.