The Inevitability of Agriculture (A Brief History of Humankind)

The farmer takes a wife, the farmer takes a wife . . .

—From the nursery song "The Farmer in the Dell"

A favorite pastime of archaeologists is to invent competing explanations for the domestication of plants and animals, which first happened around 10,000 years ago. Perhaps, one theory has it, a hotter climate, by drying up once-fertile lands, made the hunter-gatherer lifestyle suddenly precarious, and people groped for a new livelihood. Or maybe the extinction of giant elk, woolly mammoth, and other big game had the same effect. Or, on the other hand, maybe the key was a more benign environment, a climate which happened to nourish certain plants that were good candidates for domestication.

And then there is a simpler theory: Farming was just a good idea. It was a good idea in the same sense that the various tools and techniques constituting the hunter-gatherer lifestyle had been good ideas, and thus had been added to the human repertoire.

This was the radical position taken in 1960 by the University of Chicago archaeologist Braidwood. Reviewing his own fieldwork in the Middle East, where farming first appeared, he depicted agriculture’s advent as merely "the culmination of an ever increasing cultural differentiation and specialization of human communities." So far as he could tell, "there is no reason to complicate the story with extraneous ’causes.’"


Braidwood is considered the founder of the modern study of agriculture’s origins, but this particular opinion wasn’t destined for veneration. Notwithstanding his injunction against complicating the story, archaeologists have continued to complicate the story. The above cited "causes," and others, still jockey for preeminence. More than two decades after Braidwood insisted that agriculture needs no special explanation, an archaeologist, summarizing the consensus, declared that agriculture is "not yet satisfactorily explained." The search for causes continues. An air of mystery still surrounds the origins of agriculture.

Indeed, if anything, the air thickens. Some scholars now say that, paradoxically, early farmers would actually have had to work longer and harder to grow food than to just get it the old-fashioned way, by hunting and gathering. Thus the logic behind the origins of agriculture, we are told, is much less straightforward than it seemed back in Braidwood’s day.

This view poses a problem for cultural evolutionists—or, at least, for hard-core cultural evolutionists, such as me. After all, if farming was such an unappetizing prospect, how could humanity have been virtually certain to take it up eventually? Shouldn’t passage through this threshold be counted as a lucky break, a chance venture that could just as easily have been the road not taken? And, if so, doesn’t that make all that followed farming—ancient civilizations, less ancient civilizations, and so on—look far from inevitable?

Plainly, before we can get on with the rest of this topic we must dispel some of the mystery surrounding agriculture’s origins and deflate the ongoing search for "causes." Conveniently, that will give us a chance to dispel some misconceptions that persist to varying degrees within the social sciences and in various ways sap enthusiasm for hardcore cultural evolutionism.

HAPPY HOUR

The case against agriculture’s being a natural cultural advance began to gather momentum with the surprising discovery that hunting and gathering isn’t such a bad way to make a living. The !Kung San, Richard Lee found in the 1960s, work just a few hours a day—hunting, digging roots, harvesting mongongo trees—and then it’s Miller time. In 1972, the anthropologist Marshall Sahlins (a former cultural evolutionist turned skeptic of cultural evolutionism) dubbed hunter-gatherers "the original affluent society" on grounds that "all the people’s material wants are easily satisfied."

And the problem isn’t just that primitive agriculture may have been a regression in terms of sheer efficiency. The more populous villages that farming ushered in would presumably foment disease; and the low-protein, high-starch content of some staple crops might be unhealthy. Studying the bones of early farmers, some archaeologists have concluded that they had shorter lives, and more rotten teeth, than hunter-gatherers.

This brings us to misconception number one: that cultural evolutionists believe change is guided by farsighted reason. Actually, cultural evolution has involved little advanced planning. No prehistoric hunter-gatherers assembled a committee to decide whether a growing reliance on starchy foods would eventually promote tooth decay. Planted food slowly replaced wild food over many generations. And slowly the planted food became less like its wild ancestor ; it got domesticated. The question isn’t why hunter-gatherers "chose" farming, but why they chose the long series of tiny steps leading imperceptibly to it.

Part of the answer is that these hunter-gatherers were people. People are innately curious. They fiddle around with nature and try to bend it to their will.

Consider the Kumeyaay of southern California. Technically, they were a hunter-gatherer people. But, when encountered by the Spanish in the eighteenth century, they had transfigured the landscape. At high altitudes they planted groves of oaks and pines, whose nuts they harvested. Elsewhere they planted yucca and wild grapes. Near villages they planted cactus for liquid refreshment. The Kumeyaay burned off unwanted plants to pave the way for their favorites and razed dense shrubs to attract deer.

None of the plants they cultivated were domesticated. So this massive intervention didn’t qualify as farming. Still, is it really likely that the Kumeyaay could have gone another 1,000 years without breeding juicier grapes?

The Kumeyaay are far from the only "hunter-gatherers" who have given nature a helping hand. Australian aborigines replant the tops of the wild yams they eat. And remember the Shoshone of the Great Basin, often taken as paragons of the primitive? They burned off unwanted foliage, and some Shoshone planted wild food species. Some even used irrigation.

Hunter-gatherer societies that cultivate plants but haven’t yet domesticated any are sometimes called "proto-agricultural." Dozens of such societies have been observed. You might think that anthropologists would look at all these societies and say, "The impulse to groom nature seems strong and widespread—maybe the coming of agriculture wasn’t so unlikely after all." You would be wrong. Often, the reaction is the opposite. Proto- agriculture, we are told, just goes to how that many hunter-gatherers knew enough to become full-fledged farmers yet chose not to.

Often underlying such pronouncements is the unspoken premise that cultures are static; they have assumed final form; it wasn’t just that the Kumeyaay hadn’t taken up farming, but that they didn’t take up farming—end of story. Thus an evolutionary view of culture is dismissed by assuming that cultures are not in the process of evolving.

THE MYTH OF EQUILIBRIUM

The assumption that primitive culture are static is grounded in misconception number two: the idea of intrinsic equilibrium—the idea that cultures stay the same unless jostled by such outside forces as retreating glaciers or sudden drought. Happily, this notion has lost favor among many archaeologists and anthropologists. But it has more than its share of defenders—that is, more than zero—and has deeply influenced thinking not just about agriculture but about culture generally. It is the assumption of equilibrium that compels archaeologists to seek an external "cause" for any development as dramatic as agriculture.

Subscribers to the equilibrium fallacy underestimate the unsettling nature of human innovation—the extent to which new ideas and techniques spring from within societies and transform them. But downplaying our species’ genius is not the only problem. As we’ve seen, the main impediment to farming isn’t thought to be a lack of inventiveness, but rather a lack of necessity. As Marvin Harris has put it, "What keeps hunter-collectors from witching over to agriculture is not ideas but cost/benefits. The idea of agriculture is useless when you can get all the meat and vegetables you want from a few hours of hunting and collecting per week."

Here, aiding and abetting the "equilibrium" fallacy, is misconception number three: that human societies are fundamentally unified, devoted to meeting their collective needs. The mistake gets back to the romantic notion of hunter-gatherer societies as oases of communal bliss. All for one and one for all. And if all are getting enough food, then why should anyone bother trying something new?

The answer is that hunter-gatherer are in truth just like us. They’re competitive, they’re status-hungry, and, above all, they are individuals. In those hunter-gatherer societies that are proto-agricultural, the cluster of cultivated wild foods aren’t typically community property; usually they are owned by a particular family or extended family that dispenses the harvest as it sees fit. Once you start thinking of hunter-gatherer a driven by the physical and psychic needs of themselves and their families, there is no shortage of reasons why they might cultivate plants in their spare time.

Consider (once again) the Northwest Coast Indians, whose lavish use of cultivated wild plants is now coming to light through the work of the geographer Douglas Deur. A Kwakiutl household might have its own salt-marsh garden for clover roots or silverweed roots (nutritional delicacies), and might tend plots of wild berries or edible ferns. In hard times—when, say, the salmon weren’t running—the family might eat the entire harvest. But often the food would serve the family’s interests more obliquely. Being a gastronomical delight, it could be wapped for candlefish oil, and sometimes crates of garden-grown food were paired with other foods and handicrafts to fetch a prized copper hield. Often such exchanges took place between villages, orchestrated by Big Men, but non-zero-sumness also welled up within villages. A household might "give" food to a needy neighbor, with a view to future reciprocation. In the meanwhile, the giver, in addition to having garnered an IOU, enjoyed some status elevation. And families chronically in a position to "give" enjoyed chronically high status, like philanthropists.

Even in modern suburbs and small towns, avid gardeners win local esteem by giving neighbors fresh tomatoes or flowers. This strikes most of us as normal behavior. But the possibility that people might behave the same way in a primitive economy—where both the gift and the ensuing IOU were of much greater value—seems rarely if ever to cross the minds of archaeologists as they ponder the mystery of agriculture.

The various benefits of gardening were an incentive to refine it. There’s evidence that the Northwest Coast Indians were weeding out the less robust specimens, the first step toward domestication. And, to expand the level land in their uneven habitat, they built retaining walls, which had the added virtue of holding nutrient-rich soils. The Kwakiutl word for "garden" means "place of manufactured soil."

In addition to the Northwest Coast Indians and other proto-agricultural hunter-gatherer societies, there are "cultural fossils" further along in the evolution toward agriculture. Various "horticultural" societies grow domesticated crops in gardens but still rely on some hunting and gathering. Most of these societies resemble the Northwest Coast Indians, with gardening a private enterprise that pays off at the family level.

Thus, a young Yanomamo man in the jungles of South America, having just gotten married, will clear a garden for plantains, maize, cotton, tobacco, and other crops. He is not doing this for the good of his whole village. Indeed, he may surround the coveted tobacco with a fence, even plant sharp bones as booby traps. When he shares his harvest, he will do so selectively, cementing friendships, incurring unwritten IOU’s, repaying his own debts, amassing status.

THE FARMER TAKES A WIFE (OR TWO)

Could something as ephemeral as status really entice people into becoming agricultural innovator even when they face no regular shortage of food? The answer comes from looking at the top of the pecking order—at the Big Man or "Head Man," a version of which is found among the Yanomamo and horticultural societies generally. Big Men tend to have not just big gardens, but big numbers of choice wives.

The idea here isn’t that aspiring Big Men necessarily sketch out a systematic plan for acquiring multiple wives. During the biological evolution of our species, one of the benefits of male status was easier access to sex. (So too with our nearest relatives— chimpanzees, bonobos, gorillas.) Because of this correlation between status and fecundity, genes imbuing males with a thirst for status have fared well by natural selection.f The resulting drive to impress people needn’t bring conscious awareness of its reason for being—any more than hunger entails a knowledge of nutrition. Status just feels gratifying; it seems to be its own reward, even if its ultimate evolutionary purpose was genetic proliferation.

On the other hand, conscious awareness of the sexual payoff for farming is, if not necessary, hardly out of the question. When Soni of the Solomon Islands was preparing those thirty-two succulent pigs that he wasn’t going to get to eat, he no doubt knew that the more adroit Solomon Islands feast givers—that is, Big Men—got as many as five wives. Indeed, sometimes the link between amassing food and amassing wives is explicit. Among the Northwest Coast Indians and some other polygamous peoples, loads of garden-grown food could be part of the "brideprice" paid for a wife.

Archaeologists, faced with the observed correlation between a farmer’s status and wealth on the one hand, and his number of wives and offspring on the other, have tended to get things backward. Big Men are said to seek multiple wives "since many wives produce more food than one wife" and to have many children "since many children produce more food than few children." To be sure, Big Men may value the labor provided by a large family. But, in terms of the ultimate logic of their quest—the Darwinian logic that selected the genes that fuel the quest—they are amassing food to amass wives, not the other way around. If the food pays off nutritionally, that’s great, but even if it doesn’t, it is valuable, because it raises their status relative to competing males. Among the Trobriand Islanders, one anthropologist reports, farmers aimed to "accumulate so many yams that they may rot in storehouses and stimulate the envy of rivals."

The problem with scholars mystified by agriculture’s origins isn’t that they are unaware of status hierarchies in horticultural and fully agrarian societies. The problem is that they tend to view the hierarchy as a product of domestication—in which case it couldn’t be a cause. Hence, misconception number four: the notion of the "egalitarian" hunter-gatherer band.

We’ve already suggested that the venerable notion of the utterly communal hunter-gatherer band is suspiciously romantic; that the !Kung San, for example, are subtly permeated by selfishness. Are they also prone to social climbing? The answer isn’t obvious, since wealth—even in the form of a little extra food—is hard to accumulate; they live in a desert and often relocate. But it’s a good bet that if gardening were more practical, they would find that cultivating extra food was a good way to win wive and influence people. Of course, as the most industrious men exploited this fact most fully, accumulating wives and power, social inequality might grow. Still, social climbing would have been the cause of the farming, not just the result.

In a sense, this thought experiment has already been conducted—in the form of the //Gana, nearby Bushmen who supplement their hunting and gathering with farming. Among //Gana men, the anthropologist Elizabeth Cashdan has noted, the allotment of exual resources is quite unequal; one-fourth of the men have more than one wife. Writing in 1980, near the heyday of hunter-gatherer romanticism, Cashdan heretically argued that it would be wrong to see the //Gana’s social inequality as having emerged with agriculture. After all, she noted, about 5 percent of !Kung men had more than one wife. The reason the struggle for status is so subtle among the !Kung, he contended, is their precariousness; shortfall could strike any given family, so it is in each family’s interest to support an ethic of sharing, as insurance. The //Gana, Cashdan wrote, illustrate "the lifting of the constraints that produce strict egalitarianism among other Kalahari hunter-gatherers."

And full-fledged domestication is not the first step in that lifting. "Proto-agricultural" hunter-gatherer societies broadly are more likely than the average hunter-gatherer society to have conspicuous disparities in status. Apparently the Northwest Coast Indians aren’t the only people who found that home-grown food is a social lever.

It would be an exaggeration to say that all archaeologists who ponder the origins of agriculture have ignored the quest for status. Brian Hayden has championed a maverick "competitive feasting" theory, inspired by the Potlatch and other, less famous, forms of inter-village feasting. The idea is that if in any society ome aspiring Big Man—some Soni—can get fellow villagers to produce lots of food, he can use it to elevate his status in feasts with other villages. In the process he can acquire political influence within his own village.

So far so good. But Hayden describes the Big Man a a genetically distinct "personality type" present in all societies—the "aggrandizer." These aggrandizer are "empire builders; they seek to control human affair for their own benefit and gratification." In short, they are bad guys, different from such good and innocent souls as you, me, and Hayden. This is in some ways a comforting worldview, but it is at odds with modern Darwinian theory, not to mention observed social reality. To be sure, some people, for whatever reason, are more ambitious than others. But there’s a little Big Man in all of us. We are all social climber by nature. Some just manage to climb higher than others.

What does it matter whether social ambition is a property of our whole species, rather than just of the Henry Fords and Margaret Thatchers of the world? Well, the more widespread the urge to impress, the stronger the force that drives cultural evolution. If everyone is always striving for social status, then every increment in the evolution of agriculture, from the tiniest, scruffiest garden on up, is easy to explain; there’s a kind of arms race with food as the weapon.

Actually, food is just one of the weapons. Political organization is another. From the early days of agricultural history, as Hay den’s theory hints and the Sonis of the world show, coalition-building comes into play. Leader who can harness non-zero-sum logic to draw people into cooperative effort prevail in competition for status and other social resources, inviting future leader to do the same on a larger scale.

MILLER TIME RECONSIDERED

Once you realize that man does not live by bread alone—that status and sex are nice, too—the claim that hunting and gathering beats primitive farming as a subsistence technology begins to lose relevance. Of course, the logic behind agriculture would be even stronger if it turned out that this claim about hunter-gatherers was wrong, or at least exaggerated, in the first place. And it may have been. The seminal calculations of the !Kung workday—two or three hours, then party time—have been put to skeptical scrutiny and found wanting. The calculator forgot to include time spent processing the food, making spears, and so on. It now appear that these hunter-gatherers, at least, work roughly as hard as horticulturalists.

Further evidence that hunter-gatherer life is not a year-round vacation can be found in proto-agricultural societies. The Shoshone’s planted wild foods, one anthropologist observed, were "insurance" crops, and "frequently served as crucial secondary staples." So too with primarily hunter-gatherer but incipiently horticultural societies, such as the Siriono of Bolivia. While trekking through the forest in search of game, writes another scholar, they would visit their scattered gardens, "depending on them as secure sources of food energy."

All of this suggests that the layperson’s common-sense notions about life among prehistoric hunter-gatherer is on target: adversity was part of life, shortage loomed over the horizon, and fortune favored the prepared. Between the quest for status and the quest for sheer survival, we have a powerful impetus behind the evolution of agriculture.

The impetus gets even stronger when we add one more factor: our old friend from the previous topic, war. How would war encourage agriculture? In primitive war, few things come in handier than sheer manpower. And agriculture supports much larger settlements than hunting and gathering does. One of the earliest known farm towns, the ancient, excavated village of Jericho, housed hundreds of people on around six acres. Not huge by modern urban standards, but compare it to what lies beneath: remnants of a hunter-gatherer camp one-fifth as large. Imagine a battle between these two villages, and you’ll see that farming was a compelling lifestyle. Whether or not early farmers thought about the military edge their lifestyle offered, war would have helped the lifestyle spread.

Perhaps fittingly, Jericho is surrounded by a wall. At four meters high and three meters thick, with cylindrical watchtowers, this wall may have once been the largest capital project in the history of the world—a monument to the non-zero-sumness created by conflict between groups and thus intensified by farming.

THREE STRUGGLES

In the end, then, the claim that agriculture is "not yet satisfactorily explained" is misleading at best. If anything, the coming of farming was "overdetermined"—there is a surplus, not a shortage, of plausible explanations: the struggle for status within societies, armed struggle between societies, and the struggle against scarcity. Of course, "excessive" explanatory power is no scientific vice when the three explanations are logically compatible.

The archaeological record bears the clear marks of the first two struggles—wars and status competition. During the Mesolithic, just before the emergence of farming, wood and bone armor appear, cemeteries contain lots of people who died violently, and artists start depicting archery battles. Meanwhile, within societies, status competition is getting more conspicuous, with more and more bracelets, beads, and amber pendants showing up in high-status graves. (Were people trading food for these, adding an incentive to expand food production? There’s no archaeological way of knowing, but such exchanges have been seen among hunter-gatherers, as when the Pomo of northern California got acorns and fish for their beads. In any event, Jericho, the quintessential farm town, would eventually become a regional trade center.)

The third struggle—against scarcity—doesn’t leave such clear records. But we can say this much: even assuming this struggle wasn’t a central force behind the evolution of agriculture, it would have kicked in if given enough time. As the planet’s population grew—and indeed it grew faster and faster as hunter-gatherer societies grew more and more complex—the day was bound to come when nature’s cornucopia couldn’t feed the teeming masses, however ingenious their hunting and gathering.

Whatever the relative importance of these three struggles in driving the evolution of food procurement technologies, the effect was evident before farming. These technologies evolved from the Upper Paleolithic, with its well-crafted stone blades, through the Mesolithic, with its sickles, bows and arrows, mortars and pestles, nets and fancy traps. During the Upper Paleolithic, the menu grew beyond traditional staples—nuts, roots, and big game—to include birds, dangerous animals (lions, boar), and smaller animals, such as rabbits. With the Mesolithic tool kit, the menu expanded further, encompassing snails, lizards, frogs, grass seeds, lots of fish and shellfish, and lots of plants, including poisonous ones that had to be detoxified. At one hunter-gatherer village near the Euphrates River around 10,000 B.C., people were processing 157 species of plants. (With this growing environmental mastery, there was less and less need to migrate, so gardening made more and more sense. Sedentism seems to have preceded full-fledged domestication in most, if not all, cases.)

This long, clear trend—the ever-more-intensive search for food—is rather at odds with the image of hunter-gatherer sitting around picking their teeth until some external change created a sudden need for agriculture. More specifically, it is at odds with the assumption that a hunter-gatherer band wouldn’t embrace new food techniques unless they were clearly less arduous than the old ones. As the scholars T. Douglas Price and James A. Brown have noted, additions to the hunter-gatherer diet during the millennia preceding agriculture were often "more costly in terms of procurement and processing" than were existing foods.

All of this leaves agriculture looking less revolutionary than evolutionary. Hunter-gatherers had long been working hard to intensify their yield, getting more and more food from a given acre of land. Farming was "no great conceptual break with traditional subsistence patterns," in the words of Mark Nathan Cohen, one of the first anthropologists to voice doubts about the notion of a natural "equilibrium."

To be sure, agriculture would ultimately prove revolutionary, a technology that would restructure society. Indeed, the rate of social change after agriculture so surpassed the more sedate pre-agricultural rate that it is fair to speak of a kind of "equilibrium" being disrupted. But the point is that the disruptor wasn’t some external and whimsical force, such as drought or retreating glaciers, but rather internal and inherent forces, such as social striving and population growth.

Moreover, however "sudden" the changes wrought by farming, the nature of the changes was nothing new. Agriculture’s ultimate social implication—sharply elevated social complexity and non-zero-sumness—had long been manifesting itself more slowly. Toward the end of the hunter-gatherer era there were more storage huts and other capital projects requiring political leadership, more long-distance alliances, and more trade—not to mention more kinds of food and tools than ever before.

In short, Braidwood was right to dismiss the "mystery" of agriculture back in 1960 by depicting farming as merely "the culmination of an ever increasing cultural differentiation and specialization." Standard attempts to explain domestication as a response to epic change—a suddenly more barren landscape, or a suddenly more fertile landscape—are indeed unnecessary. Certainly environmental changes can add to the logic of farming, and help explain why it arose in one area before another. But if the question is why farming evolved at all, we needn’t delve into the details of climate, flora, and fauna. Given enough time, it was bound to happen.

This notion of a persistent and universal evolutionary logic behind farming helps explain an otherwise puzzling fact: farming kept getting invented, and once invented, it tended to spread. The consensus among archaeologists is that farming arose anew at least five times—three times in the New World, twice in the Old World—and possibly seven. Surely this is no coincidence.

Of course, different cultures reached this threshold at different speeds. We’ve already seen some reasons for lags in cultural evolution, and there are others. The biologist Jared Diamond, in his book Guns, Germs, and Steel, has explained many such disparities via geography. For example: some areas are more blessed with readily domesticable species than others. And species spread east-west more easily than north-south because the climate changes less, so Eurasia was a better place for crops to diffuse than were the Americas or Africa. Even so, areas that are in these or other ways handicapped often surmount their handicaps.

In fairness to archaeologists, it should be noted that few would deny directional pattern in the archaeological record, and some would even agree that the advent of agriculture was quite likely, given long enough. Still, once you start throwing around words like "inexorable," or "virtually inevitable," almost all archaeologists grow skeptical, if not disdainful.

There is an irony in the refusal of so many scholars to embrace hard-core evolutionism, and concede the stubborn force behind culture’s ascent to higher levels of organization. As we’ve seen in this topic, it is an overly "integrated" view of human society that blinds many of them to this integrative power. By thinking of hunter-gatherer societies as tightly organic, naturally and deeply cooperative, devoid of envy and one-upmanship, they overlook the subtle but strong, and ultimately productive, forces of competition within any human society—Kant’s "unsocial sociability." The harmony they wrongly perceive leaves them deaf to ongoing harmonization.

At the outset of this topic, we suggested that perhaps farming arose simply because it was a "good idea." But "good" in what sense? In the sense that it helped people avoid starvation? In the sense that it helped people win wars? In the sense that it helped people gain status? Yes—in the sense that it helped people do the things that people try to do. And, by virtue of thus satisfying people, the idea of farming was "good" in another, very fundamental, sense: it was good at getting itself spread; in cultural evolution’s war of all against all, the concept of farming was a survivor.

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