The Big Ratchet: How Humanity Thrives in the Face of Natural Crisis (3 page)

Such a massive shift is bound to reverberate into a family’s decisions about how many children to bring into the world. When humans pivoted long ago from nomadic forager to settled farmer, women began to have more children. The Big Ratchet has seen precisely the opposite shift. With more children surviving, and contraception becoming available, women began to have fewer children, especially when they had access to education and jobs. A rationale for large families disappeared as labor-intensive farm life
gave way to city living. Women married and had children later in life. We can all probably trace this arc of large to small families with a view back a few generations into our own family trees.

The shift from high death and birth rates to low rates for both is known as the demographic transition. It is responsible for the massive explosion in the number of mouths to feed during the Big Ratchet, although it began in
around 1800 in northwestern Europe. The Big Ratchet’s transition ranks among the largest demographic upheavals in human history, and in most countries it is still underway. In 1800, there were 950 million people in the world. By 1900, there were slightly more than 1.5 billion. And then the population began to explode: to 2.5 billion in 1950, 6 billion in 2000, and nearly 7 billion by 2010.

The dramatic upswing in numbers probably won’t level off until 2050, by which time there could be 9
billion people on the planet. By that time, nearly seven out of ten people will likely be living in cities, up from three out of ten at the
midpoint of the twentieth century. Human ingenuity will be put to the test yet again by all of those mouths to feed and stomachs to fill, by all of those people in cities buying their food in stores rather than growing it on the farm.

The Big Ratchet that took place during the second half of the twentieth century has one remarkable feature: The amount of food produced not only kept pace with the ballooning number of people, it surpassed the amount available for each person when the Big Ratchet began. If all the people in the world were to receive equal shares of food, which of course
they do not, then each person would have had about 2,200 calories each day in 1960 and about 2,700 in 2000—
despite the surge in population.

This is quite an accomplishment for a species whose members started to become farmers only 12,000 years ago. But here is the rub: only those who could afford to pay the bill could share in the bounty, and that leaves out a large portion of humanity. It leaves out most of the people living in the poor countries of Africa. It leaves out many in India, Brazil, and other countries, too, where economic engines have started to churn, but those on the bottom rungs of the ladder have been left out. The result is that the number of people who went to bed hungry every night dropped only slightly below the 1 billion mark, leaving about two out of every thirteen people
undernourished at the end of the twentieth century. Even for those who can consume more calories, it’s debatable whether they have healthier diets. Whether the planet can withstand the onslaught is another unknown.

We can only see the dynamics that drove humanity’s journey from forager to farmer and then from farmer to urbanite with a long-term view. Societies adapt, learn, and alter course when conditions change. Simon’s and Rockström’s short-term views fail to grasp that there is no endpoint to this interplay between human ingenuity and nature. The long view circumvents outdated romantic notions of a pristine nature that humanity is violating. Human civilization is part of nature, and nature is part of human civilization. As long as civilization exists, we will be grappling with how to hijack nature to feed ourselves. And we will never escape the fact that all abundance, including the plenty in current times, results from temporary solutions.

Civilization’s Engine

Food is the ultimate energy source for every human endeavor. It is more essential than coal, gas, or any of the other sources that power
our machines. Without food, there can be no cities, trade, cuisines, language, great artwork, symphonies, novels, theater, or any of the other hallmarks that set our species apart from others. From the wild plants of hunter-gatherers to the packaged cereals of the urban shopper, food has always been and will always be the engine of civilization. Although we normally think of civilization in terms of culture and technology, we might equally define it as a combination of nature and human ingenuity. This combination is what provides enough surplus to allow a portion of the population to engage in activities other than producing, preparing, and storing food.

Take, for example, ancient Jericho, the earliest known urban center, located near the Jordan River in Palestine. Today, ancient Jericho would seem like little more than a small town. About 2,000 people lived there by 8000
BCE
. Perennial, clear spring water from a nearby oasis watered fields of wheat and barley. More grew in a single year than Jericho’s people could eat. The surplus allowed some of the people to specialize in making pottery or jewelry, engaging in religious worship and rituals, keeping order, and performing other tasks. Not everyone’s daily life had to be directly related to
farming or preparing food.

Jericho and the towns that sprang up later were little more than isolated islands of sedentary farmers living amid nomadic groups who hunted and foraged for their food. But the towns set in motion the future of civilization and numerous inventions and achievements, including the plow, writing, bronze, modern science, machines, and medicine. Settled life also triggered stratified societies dominated by elites who controlled the surplus and usurped the benefits for themselves. For good and for bad, from the times of ancient Jericho until today’s bustling cities of São Paulo, Mumbai, and New York, among many others, densely packed settlements with people specializing in different tasks would not be possible without agriculture to grow surplus food.

The link between farming and complex civilization is
not unique to our species. Humans, in fact, are a relatively recent addition to the
list of species that farm. Our species devised the trick only 10,000 to 12,000 years ago. Insects had it figured out millions of years before. Leaf-cutter ants, found today in South and Central America and the southern United States, are among the original farmers, constructing complex mazes of underground caverns to house fungus farms. The ants bite green leaves into tiny pieces and carry them underground to the farm. There, they chew the leaves into pulp. They deposit the half-digested mass as it moves through their guts. Tiny, mushroom-like fungi then grow on the decaying rot of partly digested leaves, providing a nutritious food for the ants. Termites practice the same ecological trick, constructing fungi farms in underground combs beneath their mounds. Ambrosia beetles grow their fungi in intricate burrows bored deep into tree trunks, where they raise their broods of larvae on the nutritious fungi crop. So our use of livestock for meat and dairy animals for milk is not really all that unique.

Regardless of which species is farming—ants, beetles, termites, or humans—complex societies with specialized tasks are the norm once farming becomes the strategy to produce food. The evolution to farming made it possible for millions of individuals to live in the same mound,

nest, tree burrow, or city. The transition to farming and complex societies is so drastic, in fact, that no farming species is known to have reverted to a non-farming existence.

Very few species farm, but all plants and animals play ecological tricks to produce food, expand their numbers, occupy every possible niche, and outcompete their rivals for space and nutrients. Microbes in the deep sea extract energy from the heat of vents on the ocean floor. Plants fuel growth by combining the sun’s energy with carbon from the air. Animals eat plants and other animals, exploiting the sun’s energy through plants as intermediaries. But our species has one trick that others do not. Other species rely on genes to shape their evolution. But humans have memes as well, an idea Richard Dawkins articulated to describe the ideas that spread and
shape human culture. Successful memes persist and evolve. Unsuccessful memes die a quick death, just as species unable to survive go extinct.

Memes to fill our stomachs have persisted, spread, and morphed into bigger and better memes throughout the history of human culture. Memes to purposefully select edible plants and animals, to move water to irrigate crops in places where nature does not supply a ready source, and to extract fertilizers from air and rocks are only a few of the ingenious innovations humans have used to enhance nature’s bounty. Today’s view from above reveals tens of thousands of years of successive, ever more clever ways to wrestle food from nature, ratchet up our numbers, and expand across the planet.

The Irish Pivot

One infamous example of the ratchet-hatchet-pivot cycle centers on the humble potato and
Ireland’s Great Famine. The potato’s ascent as an Irish staple began with Christopher Columbus’s 1492 arrival in the Americas. Eventually, ships carried South America’s native potato from the New
World to the Old. The first evidence of the potato’s arrival in Europe comes from the record of a hospital purchase in
Seville, Spain, in 1573.

The potato diffused slowly throughout Europe, encumbered by suspicions of poison and notions that its bumpy resemblance to a leprosy patient meant that it spread the disease. Gradually, potatoes earned a prized place on farms, thanks to their advantages over other staple crops. The energy- and vitamin-rich potato required less land than wheat, barley, and other staples to grow the same amount of calories. People could subsist almost solely on a diet of potatoes supplemented by only a bit of meat or dairy. Potatoes stored easily, and they could grow along with other crops. All of these factors made the potato wildly popular. By the beginning of the eighteenth century, potatoes were common throughout Europe.

People grew taller with potatoes in their diets. French soldiers growing up in potato-eating villages were about half an inch taller in the late 1700s than their predecessors a century earlier. Thanks partly to the potato, people lived longer and had more children. Historians today estimate that the potato accounts for about one-quarter of the growth of Europe’s population between 1700 and 1900, with better health and
sanitation explaining the rest. The pivot to the potato set in motion a powerful ratchet.

No one relied on the potato more than the poor peasants of Ireland. At the beginning of the nineteenth century, with the industrial revolution in full swing, factories in England were drumming cottage industries out of business, compelling more Irish families to farm for their daily meal. At the same time, rich landowners were evicting tenant farmers from their estates so they could produce more profitable livestock and
grains for export to England. As landowners usurped more land, potatoes became the only viable choice for peasant families. A few decades into the century, the growing population of poor Irish peasants was subsisting almost exclusively on the common Lumper potato.

A useful attribute of potatoes is that a plant can sprout directly from another potato planted in the soil. There was no need for the farmer to buy seeds. But this key feature proved to have a devastating downside. Potatoes were genetic clones of each other. And because fields were close together, the potato plants were perfect targets for pests. Unlike in South America, no genetic variants that might have been able to withstand an onslaught stood in the way of a fatal pest sweeping across the fields.

The fungus that caused the potato blight hit hard in 1845, setting in motion the Great Irish Famine. The potato had ratcheted up the number of mouths to feed. Then the hatchet fell: pestilence, famine, and death. Potatoes rotted in field after field. Few potatoes remained from which to plant a new crop, and the fungus returned in later years to prey on those that did. Lack of jobs and limited prospects for more land left the poor with few options. A million people, one-eighth of the Irish population, died. Another million left for other parts of the United Kingdom and the New World.

The Irish population has never recovered to the 8 million of 1841, but there has not been a major famine in Ireland since. For those who remained behind, new varieties of potatoes offered respite against blights. Pastures took the place of many potato fields, and factory jobs replaced farming. Today, the fungus still plagues potato farmers, but blight-resistant strains bred from South American wild potatoes, combined with pesticides and potatoes being planted further apart, have reduced the threat. The pivot followed the hatchet in a new twist of the cycle.

Seen through a political lens, British exploitation of their neighbors and disregard for the peasant’s plight were at the heart of the famine. The genetic clones and the fungus are to blame if one views the famine through a purely ecological lens. With a short-term lens, the famine was an unmitigated disaster for many—indeed, very nearly a collapse. None of these lenses alone, however, captures the whole story
of Irish resilience in the face of a devastating tragedy. The picture of a society that changed and adapted, rather than collapsed, emerges only from a view through the long-term lens. The story of the Great Famine is a microcosm of humanity’s journey through the ratchets, hatchets, and pivots that typify our history. We can only see the journey clearly through multiple lenses.