Published in World Politics Review 24th January 2023
There is something very wrong with global food production. From farm to fork, the food system as it currently exists is the most environmentally destructive of all human activities. More than half of the Earth’s habitable land is used for agriculture, and the replacement of natural ecosystems with farms and ranches has devastated biodiversity. Over the past 50 years, the average size of wild animal populations has decreased by nearly 70 percent. Life on Earth is now entering one of the greatest mass extinction events in tens of millions of years.
At the same time, the food system is now responsible for a quarter of all greenhouse gas emissions, making it a bigger driver of climate change than transport. In feeding ourselves, we are in the process of consuming the Earth and hacking away at the natural world’s vital life-supporting systems.
This is a story about the Green Revolution, as the transformation of food production since the middle of the 20th century is known, and what it has done to our planet. That it is called “green” is ironic, because in feeding humanity, we have in fact turned much of what was green onEarth into deserts. Some of these are literal deserts, where intensive farming practices have accelerated soil loss, leaving once-verdant areas barren. But most are biological deserts, vast regions of the planet in which only a few select species of plants or animals live. We call these regions farmland.
There are, however, solutions to these challenges. Some deploy the latest advances in science and technology, while others revisit ancient practices. But they all acknowledge that things must change rapidly if we are to avert potential ecological disaster. For that to happen, we must understand how we got here and what may be holding us back from revolutionizing the way we grow our food.
Expanding Agriculture, Exploding Populations
Near the end of the 18th century, Thomas Malthus wrote that “the power of population is indefinitely greater than the power in the earth to produce subsistence for man.” Malthus is perhaps the world’s most famous demographer—someone who studies the structure of and changes in human populations—and probably the most infamous; Malthusianism, a broad school of thought surrounding notions of overpopulation, is named after him.
Malthus was right about the potential for populations to rapidly increase. Whether they are human, rabbit or some other species, populations have the potential to produce explosive, exponential growth. More people means more babies, which grow into more reproductively active adults, resulting in more babies. Such reinforcing feedback loops typically do not end well. Malthus argued that the United Kingdom’s rapidly increasing population in the 18th and 19th centuries would soon outpace increases in agricultural output. He believed that when that happened, the inevitable result would be famine, starvation and death.
We can only imagine what Malthus would think about what population has done since then. When his landmark book, “An Essay on the Principle of Population,” was first published in 1798, the world population was approaching 1 billion. In 2022, it surpassed 8 billion, an increase of 800 percent. Yet despite this huge increase, and although we are facing enormous food system-related challenges today, Malthus was spectacularly wrong: The population-driven famine and disaster that he predicted hasn’t materialized.
How, then, did humanity avoid the crisis that could come with overpopulation? And how have we managed to feed an additional 7 billion people?
In order to answer such questions, we first must understand where all these additional people came from. Because in answering that, we will also understand how agriculture revolutionized our lives, while setting us up for even bigger problems.
The Impact of the Agricultural Revolution
Caption: The increase in the total numbers of humans on Earth appears as a near vertical line when assessing its change over thousands of years.
Modern humans emerged in Africa around 250,000 years ago. The global population gradually increased as humanity slowly spread across the rest of the planet. At the end of the last ice age some 11,500 years ago, the total number of humans was anywhere between a few hundred thousand and a few million.
Then everything changed, as human populations shifted from a roaming hunter-gatherer lifestyle to one organized around sedentary farming. Some of the earliest evidence for farming is found in the “fertile crescent” region of Western Asia and North Africa. Around that time, fig trees were being planted in what is today Jordan, while cereals were being grown in the area now known as Syria. Further east, rice was being grown in China.
This was the start of the Neolithic Revolution—the first agricultural revolution—which happened independently at various sites in South America, Africa, the Middle East and Asia. It is from this time that the first major civilizations arose. And it was this shift that allowed for much more food to be produced within smaller areas.
Population density increased, and along with it, social complexity. Previously egalitarian societies started to become much more stratified, with the benefits of agricultural surplus being used to trade and the benefits of such trade becoming concentrated in a smaller fraction of society. Populations gradually increased as more and more of humanity took up farming. For example, the practice of planting seeds and rearing animals spread out from the fertile crescent into Europe. By around 5,000 years ago, farming had fundamentally altered human societies on the continent.
Thousands of years of progressive development of farming practices produced gradual but continual increases in food production. A step-change in development took place in England in the 18th century, a period that saw the development of more efficient ploughs; widespread introduction of the practice of crop rotation; the increase in farmland by draining peatlands and bogs; and the development of food transportation and markets. These and other developments drove a remarkable increase in food production, which generated an excess of food and helped spark an increase in the country’s population. Malthus was concerned that agricultural surpluses would not be able to continue outpacing England’s increasing population for much longer, given the potential for exponential population growth.
But growing populations helped spur on the industrial revolution, As more people were available for more factory work. This increased economic activity and innovation, some of which made its way back to food production. It may even have been the case that dwindling supplies of food, due to England’s increasing population, was an important driver of agricultural innovation in the country in the first place. That necessity can be the mother of innovation was the key conclusion of Danish economist Ester Boserup’s landmark book “Conditions of Agricultural Growth,”. Published in1965, it explored how preindustrial agriculture came to be reformed by continual risks of food shortages. She documented numerous examples where people reorganized farming practices to produce more food from the same amount of land, a process termed agricultural intensification.
By the middle of the 20th century, this intensification was turbo-charged by a tremendous leap in global population after World War II. Increasing industrialization and development had produced significant year-on-year reduction in child mortality in nations around the world since the 1900s. Better sanitation, health care and vaccination programs led to far fewer infant and adult deaths. While birth rates remained high, populations soared: It had taken humanity over 200,000 years to reach 1 billion people in 1804, but only 126 years to reach 2 billion in 1930. Thirty years later, in 1960, world population passed 3 billion, while the 4th billion was added in as little as 14 years. Such explosive growth set the scene for the next step-change in agricultural production: the Green Revolution.
The Green Revolution’s Complex History
In 1970, U.S. scientist Norman Borlaug received the Nobel Peace Prize in recognition of his seminal contributions in increasing food production, and he has since become a central figure in the history of the Green Revolution. It is often claimed—and with good reason—that he saved over a billion people from starvation. Starting in the 1950s, Borlaug, along with other crop scientists, developed high-yielding strains of staples such as wheat that rapidly replaced traditional strains across the world.
Used in conjunction with industrially produced nitrogen and phosphorus fertilizer, water irrigation and pesticides, these strains rapidly increased crop production. Meanwhile, the increased use of machinery, such as large tractors and combine harvesters, meant bigger fields could be cultivated. Mexico was one of the first countries where these changes were widely adopted, and by the early 1950s, its agricultural output was increasing. In the 1960s, the Philippines, India and Brazil and other developing nations were similarly undergoing rapid changes in their farming and food systems.
All this took energy, supplied primarily by coal, oil and gas. This intensification of agriculture, along with more of the Earth’s land surface being used for farming, meant food production has managed to keep pace with the unprecedented population growth of the past 70 years. The amount of food that humanity now produces is staggering. In 2018, global crop harvests measured 9.2 billion tons. Of that, half came from sugar cane, maize, wheat and rice. In that same year, 342 million tons of meat was produced, 90 percent of which came from pigs, chickens and cattle.
Yet, such extraordinary success in terms of food production has come with environmental impacts at a similar scale. The amount of emissions created from powering tractors, delivery trucks and freezers is considerable, but most of food’s climate impacts come from livestock. The hundreds of millions of tons of meat we consume are produced by 780 million pigs, 1 billion cattle and a staggering 33 billion chickens. Today, the very highest rates of meat consumption per person—which is strongly related to wealth—are in the U.S., Australia and in Europe. But other nations, such as China, are catching up as their middle class expands.
Of particular concern is the climate impacts of cattle. Animals like cows have evolved digestive systems that can break down the tough fibers of grass by cultivating microbial communities in a special gut. This allows the cows to ferment the grass to increase the amount of nutrition they can extract from it. A by-product of this fermentation, however, is methane, a very powerful greenhouse gas. One billion methane-burping cows adds up to a big climate change problem.
Livestock is also the leading cause of ecosystem destruction. Seventy-seven percent of farmland is used to rear livestock or grow the crops that are fed to livestock. In Europe—another region of high meat consumption—over 60 percent of all cereal crops are used to feed animals. But it is beef-rich diets in particular that now present the biggest threat to global biodiversity. The most acute example of this can be found in the Amazon rainforest, where some of the greatest stores of biodiversity are being destroyed to clear land for ranching cattle or for growing soy that is used primarily for animal feed.
It is these planetary-scale impacts that are behind calls for a new agricultural revolution, a “greener” revolution that would shift away from these destructive modes of production to ones that can generate more food, without contributing to catastrophic climate change and ecological collapse.
A Path Forward—and Obstacles in the Way
In essence, the challenge the world is facing is to produce enough food and to transport it efficiently to those that need it, while simultaneously reducing environmental impacts. This is a daunting task, but there are rays of hope that, collectively, could illuminate a path toward truly sustainable food production systems.
First is agroecology, an approach to farming that seeks to restore biodiversity and reduce climate impacts while producing more nutritious food. The key to agroecology is to work with nature, rather than try to overwhelm it. For example, in 2002, a community farming program in Zambia’s Luangwa Valley began to implement zero-tillage farming, which involves applying home-made fertilizer to each plant. This reduced fertilizer costs, helping farmers to save 10-20 percent of their annual income. It also helped suppress weed growth and reduce carbon losses from the soil. By planting different crops at different times—the practice of crop rotation—vital nutrients such as nitrogen were replenished naturally in the soil.
Agroecology has spurred interest across the world in regenerative farming practices that work to rebuild ecosystems on farms, beginning at the soils and then encompassing all elements of production. This approach has been championed by U.K. vegetable producer and distributor Riverford, for example, which serves over 90,000 customers nationwide. Riverford deploys native wasp species on it farms to eat the aphids that would otherwise eat its crops.
Second is agroforestry—growing food alongside trees—as tree coverage produces microclimates in which water vapor is increased, while also stabilizing soils and providing a home for a wide range of wild organisms. It is within these more diverse and functional ecosystems that crops for human consumption can thrive. With care, the balance of ecological forces can be tipped in our favor.
In Ethiopia, for instance, smallholder farmers grow crops and vegetables near and within the cover provided by naturally growing trees. Agroforestry food systems have also long been central elements of Polynesian societies, and they have inspired more industrialized nations to apply agroforestry techniques to intensively farmed land. Last year the U.S. Department of Agriculture allocated $60 million to advance agroforestry in 37 states across the eastern U.S. and Hawaii.
Finally, some of livestock’s climate impacts can be reduced by introducing seaweed into cattle feed to reduce the amount of methane that cows generate. There are also recent advances in lab-grown meat that offer the promise of dispensing with rearing animals altogether. But such innovations come with their own energy costs and so cannot be considered a silver bullet. At the moment, the fastest way to reduce the environmental impacts of livestock is to simply reduce the total amount of meat we eat.
A major obstacle to reducing meat consumption is that meat production is very big business. The world’s largest meat processing company, JBS, headquartered in Brazil, employs nearly a quarter of a million people and slaughters 14 million animals each day. In 2021, it recorded annual revenues of $65 billion. The greenhouse gas emissions involved in rearing the company’s chickens, cows and pigs is larger than the entire annual emissions of Italy. While JBS has made commitments to increase the sustainability of its operations, we cannot expect meat production of such scale to be decoupled from most of its environmental impacts.
Consequently, there is increasing interest in ways to reduce demand. The good news is that we don’t need everyone to become vegetarian or even vegan to see big improvements. Initiatives that have taken off globally, such as meat-free Mondays, have proved to be very successful in getting people to make small shifts toward less-damaging diets, not only helping to reduce climate and ecological impacts, but also leading to improvements in health. Additionally, research conducted by the University of Oxford concluded that eating meat no more than three times a week could prevent 45,000 premature deaths a year in the U.K. alone, and could save the U.K.’s National Health Service £1.2 billion, $1.45 billion, each year.
One regulatory option to help reduce consumption would be to impose a “meat tax,” which would increase the cost of meat in proportion to its environmental footprint and so reduce total meat sales, with beef being taxed most heavily. The risk in doing that is that it could push more people into food poverty. However, a study conducted by Chatham House argued that a portion of the revenues raised by a meat tax could be used to support low-income households to buy their food as well as promote regenerative farming practices.
Above all, the most effective way to reduce pressures on food systems would be to use the food we produce more efficiently. Each year, nearly 1 billion tons of food is thrown away. These losses come from food perishing before it reaches the market, being rejected by retailers and, most important of all, being purchased but not eaten. Reducing food waste is a key objective of one of the United Nations Sustainable Development Goals for precisely that reason, as the sheer amount of land, water and climate impacts that could be mitigated by reducing food waste is enormous. In the U.S. alone, the greenhouse gases used to produce the food that is ultimately left uneaten is the same as the tailpipe emissions from 32 million cars.
Reasons for Optimism
There are some reasons for optimism. In 2016, France banned supermarkets from throwing away food approaching “best before” dates, which unlike “use by” dates are simply recommended guidance and not strict regulations related to food safety. Instead, supermarkets were encouraged to donate this food to charities. More recently, major supermarkets in the U.K. have voluntarily ditched these same “best before” labels in an effort to reduce some of the food that is wasted by either not being purchased or thrown away after being bought in the belief that the food could be unsafe. At the same time, consumers can be encouraged to make modest changes, such as only buying what’s needed for the next couple of meals when it comes to fresh produce.
But what about the ever-growing world population? Won’t the sheer number of humans demand ever-more intensive and destructive farming practices? Not if we make the right choices.
While the total number of humans is still increasing, this rate of increase is slowing down as global birth rates decrease. The reasons for such changes are complex, but access to free contraception and keeping girls in school for longer are perhaps the most important factors. The U.N. currently estimates that world population will reach nearly 10 billion by the middle of this century, and then top out somewhere around 11 billion by 2100. Rather than worry about the total number of people, we should instead focus on the very large inequalities in climate change impacts from dietary habits and other behaviors. The richest 10 percent of the world’s population were responsible for over 50 percent of all greenhouse gas emissions between 1990 and 2015.
By using existing land more efficiently, reducing food loss and taking care of how food is distributed, we could feed all of humanity sustainably. This would require changing farming practices, reforming big business and producing some large shifts in consumer behavior.
No one argues this will be a piece of cake. But if our industrialized societies are to have a long-term future on Earth, then we must initiate a new agricultural revolution that satisfies human needs, while respecting Earth’s limits.
James Dyke is an associate professor in Earth system science at the University of Exeter. His book “Fire, Storm, and Flood: The Violence of Climate Change” was published in 2021. He can be found on Twitter at @jamesgdyke. His personal website can be found here.