This is the seventh article in a 12-part series about the Earth-system, how our planet has shaped us as human beings, and how we, in turn, have shaped it The article appeared here first, in Unraveling Climate Change, a series for The Wire.
It takes energy to get food—whether you’re chasing it in a hunt, climbing for it in the trees, digging it out of the ground, or farming it and trucking it across the country. Most animals, of course, lack trucks or other vehicles, so whatever food they eat they must gather on foot (or fin or wing). But for an animal in balance with its healthy home environment, it will be enough. Our human ancestors also acquired enough energy and materials from gathering and hunting to reliably reproduce at a slow and steady rate, make their tools and artworks, dance and sing and play and participate in other essentials of community life.
But sometimes the landscape provides an unexpected stockpile of food, so that one need expend hardly any additional energy to gain lots more of it. When human societies—or any other living systems—gain access to such a source, they may experience this as a sudden expansion in the carrying capacity of their environment; that is, suddenly the same amount of effort returns enough energy and materials to make and support a lot more of them. We might call this a ‘cheap’ supply of energy and materials that stimulates growth.
Notice that in living systems the consumption of energy and materials are linked: if a system is able to use (consume) any new source of energy, it will do so in conjunction with an increased usage of materials, whether that material is the food itself or other materials—like firewood or coal or iron—that are acquired by expending that energy. Imagine, for instance, beavers living along a river encaged as a zoo exhibit. If zookeepers leave them extra food and let them do as they please, they will become more beavers, who will then cut down more trees—as beavers are wont to do—and then build larger dams or more dams, increasing the overall size and complexity of their beaver world along their river. It is the combination of energy and materials that a living system uses to grow in size, number, or complexity.
Or consider what happens with mice and locusts, when they discover food concentrated on human farms. Mice can give birth to a half-dozen new babies every few weeks. If a few mice have access to tons of food stored in a grain silo, their population will grow exponentially, exploding over a few months into ‘a plague of mice.’ Something like this happens periodically in Australia, when hordes of mice swarm the countryside, scouring farm after farm. Locusts too move from the bounty of one farm field to the next, eating and reproducing and growing by the week into giant swarms that overwhelm entire regions. This happened in eastern Africa between 2019 and 2021, their numbers swelling as they traveled up and across the Arabian Peninsula, into northern India.
However, perhaps unknown to the mice or locusts, the grain silos and farm fields are not actually unlimited sources of food. What had felt like a sudden expansion of the land’s carrying capacity is actually merely temporary, illusory. The booming mice and locust populations are now exceeding the true carrying capacity of their ecosystem—that is, the sustainable carrying capacity, beyond any temporary glut of food. So as their numbers shoot upward, they’re ascending a ladder to nowhere but impending disaster through overpopulation and environmental despoliation: ecological overshoot.
An overwhelming concentration of mice, for instance, can produce so much excrement and masses of dead rodent bodies that the land can’t reabsorb it all quickly enough through natural processes of decay and renewal. If they’re unable to leave the area, their waste will build up until it taints the ground and the water and even their food stores. Dense crowds are also harbors for disease, so the swarm can become afflicted by its own epidemics. Eventually, as the food supply runs down from having been a surplus to no longer being adequate for their burgeoning population, they begin to go hungry. The stress of these horrid conditions can also make the mice more aggressive, causing them to turn on each other and fight. Their population peaks and then crashes, as the mice succumb to starvation, disease, and violence.
It is a law of life that nothing grows forever, and certainly not at an exponential rate. Due to the inherent limits in how quickly an ecosystem can reabsorb waste and replenish itself, there are limits to growth; these are biophysical limits, set by the conditions and dynamics of healthy ecosystem functioning. In fact, at every level of a healthy living system—cells, tissues, individuals, populations—there are limits to the growth of each part based upon the whole system’s dynamic stability. A part generally grows only until it matures; then it stops growing. If part of a living system does not stop growing, we recognize this as cancer, a part of the body turned malignant to the whole. If it continues to grow without restraint, it will ultimately kill its host body and thus kill itself.
Therefore, if we recognize the human economy as a living system, we must question its logic of eternal growth. The human economy is a part of the planetary biosphere. It takes resources from its host (the planet and its biosphere) to sustain itself. This dynamic is normal for living systems, and it can be maintained within limits—a balance of give and take, as I’ve discussed in a previous essay. Yet, in modern times, we’ve done whatever is necessary to encourage the unlimited growth of the economy, negatively impacting the biosphere. Following the logic of cancer—growth without restraint—our modern human enterprise is eating its own life-support system, its living substrate. It has overshot its sustainable boundaries. It will crash.
This is unmistakably apparent today, with our mounting ecological crises that are leading to mass extinction and climate change—not unlike the organ-systems failure in a body beset with cancer. But this general trend isn’t entirely new. Some human populations in particular localities had already been growing too big too fast for several thousands of years. This is what led them in some parts of the world to inhabit densely populated cities and form centralized governments, beginning around five thousand years ago.
The Holocene presented humanity with the first prolonged period of stable and warm climate conditions our kind had ever experienced. In the early millennia of this climatic anomaly, many peoples across the world were already experimenting with plant selection. They did this simply by encouraging their favored plants to grow more abundantly as and where they were already growing, by tending, managing, and shaping their local ecosystems, not annihilating them. Some people planted gardens, favouring vegetables and greens; but after a season or two, they allowed their small garden plot to be reabsorbed back into its ecosystem, while they continued a nomadic lifestyle and later grew another garden elsewhere. This system, called swidden (jhum) cultivation, avoids overtaxing any particular locale, allowing the environment to regularly replenish its integrity through rewilding. Thus, these were sustainable fashions of food cultivation at low population densities.
The peoples of the Fertile Crescent and the Yangtze and Yellow River Valleys were also managing their local ecosystems based on similar principles. But one difference was that they first favoured cereal grains. The nature of this food would slowly push their systems and methods away from holistic ecosystem management toward the dynamics of intensifying centralization, away from a more outwardly directed worldview toward a more inwardly focused one. For one thing, to a greater degree than other types of foodstuffs, cereal grains are easy to harvest and process using routinized, efficient methods. Suddenly, a lot more food became available without a lot more work. And based on this easy surplus of food, their populations mushroomed.
But predictably, their surpluses began to falter under the weight of their growing populations. Just like what happens with a plague of mice. Compared to mice, however, humans didn’t seem so helpless in the face of their mounting problems. Thanks to their culture, cooperation, and powers of imagination, humans have a much greater repertoire of possible responses. With the help of new technologies, humans could intensify their efforts: They would figure out how to keep extending the food bonanza, feeding an ever growing number of bodies.
The solutions those earliest farming peoples devised did avoid immediate population crash, but also led to different, negative consequences within their communities, including the rise of elite classes of people and the disempowerment of others. This enabled a second major energy transition (after fire) in the human story: forced labor. Low-status humans and animals were enslaved or otherwise coerced or ensnared into expending their own bodily energy for the benefit of others. And much like the mice, these cereal grain specialists probably didn’t realize where their collective actions would lead, as their intensified efforts were more deeply overtaxing and despoiling the land—thereby actually extending their degree of ecological overshoot.
So, as both the Fertile Crescent and the Yellow River Valley were being over-extracted, farmers were spreading themselves and their technologies further across the landscape—running from ‘silo’ to ‘silo’ in need of new land and new resources to make up for what they’d exhausted. Eventually, some would discover the astounding energy surplus stored within combustible fossils—another major energy transition—sparking the Industrial Revolution. This further fed the growth of the human enterprise by making all resource consumption—from food to wood to minerals—faster and more intensive.
Combustible fossils are the only source that can provide the unprecedented rate of energy flows that underwrites the human enterprise today. This stockpile of surplus energy has led us to imagine we’ve liberated ourselves from planetary constraints. We’re lulled into imagining we’ve increased the human carrying capacity of the planet, that the proverbial pie has grown larger. But this is an illusion.
Though we can’t directly eat fossil energy, we can expend it to mechanize food production, delivering more food to more people with less direct human labor. We also expend it to excavate and deploy all the other surplus materials we desire in order to grow the complexity of the human enterprise, to build all the things that enable our increasingly layered socioeconomic hierarchies and bureaucratically structured sociopolitical worlds.
For, not only has the sheer number of humans massively increased since the Industrial Revolution, but so has our stuff: cosmetics, clothes, toys, gadgets, houses, restaurants, hotels, cars, roads, ships, shops, cables, satellites, data centres, etc. As well as our institutions: banks, schools, governments, militaries, universities, research labs, think tanks, corporations, governmental and non-governmental organizations, etc. We might think of all those physical artifacts as parts of our built habitat—not unlike beaver dams or beehives—which are needed to participate in the social reality shaped by the growing complexity of our institutional systems. But this industrial ‘nest’ we’re building has grown so large that it’s destroying entire ecosystems and displacing other living systems, including alternate ways of human thriving.
Systems theory tells us that attaining higher degrees of centralizing complexity requires more energy, because complexity—as instantiated in, for example, our multiplying social and economic institutions, our nested layers of governance, the tangled supply chains that feed consumerism, our modes of warfare—arises in opposition to entropy. Or to put it plainly: it takes more work (energy) to build and operate something that has more interdependent parts than something that has fewer.
And each level of centralizing complexity we add demands an increasing share of energy invested to keep it running; that is, each modicum of energy invested gives diminishing returns. Thus, this complexity is ultimately a self-limiting phenomenon; how far it succeeds depends fundamentally upon the amount of energy available to the system. History bears this out, given that every complex society ever built has peaked and then slumped. Industrial civilization, built on the fossil energy bonanza, has reached a level of centralizing complexity previously unattainable. But this energy too is limited—as are the natural resources required to continue building and servicing it.
What’s more, this kind of complexity takes resources from its periphery to feed its center; thus, any growth or stability at the center is maintained at the expense of the periphery—in our case, that includes the atmosphere, the biosphere, the poor, the voiceless, the unseen or unheeded. This is why capitalism—a complexity-increasing driver of our system, devised to efficiently move material wealth from the peripheries to the core—ends up creating poverty and requiring violence and exploitation as integral to its functioning.
Our increasing use of surplus energy and associated materials builds and maintains this system, as humans grow in number and our enterprise grows in complexity. But given the finite size of our planetary host and its diminishing resources, the present system is nearing the limits of its growth trajectory before its inevitable crash. Indeed, for a highly complex system, such as ours, by the time the destabilizations of the periphery are being felt at the center, the dynamics of systemic breakdown will already be well underway. And we are today already at a point where we can see those damages closing in upon the center. This is why many at the center have finally started noticing the problems that Indigenous groups at the margins have been warning about for generations, from climate change to biospheric collapse.
Everything is connected and every living system has its healthy operating limits. If we exceed them, we impair the system’s healthy functioning. When that system is our own ecosystem—the essential, biophysical basis of our very lives—we are threatening our own survival. New technologies can temporarily distend the limits at the center of a system by more efficiently or invisibly externalizing harms to its peripheries. But they cannot ultimately remove these limits. The limits will always reassert themselves as those harms eventually ripple back from the edges toward the center, and the consequences of overshoot are felt at its heart. It’s imperative that we understand there are real, hard limits to growth. We cannot continue the present mythology of unlimited growth on a finite planet.
Though we remain, as a global society, locked into the paradigm of growth at all costs, growth is a value that only began to rise with the Agricultural Revolution, itself. Despite the stories we tell ourselves today about growth being linked to human ingenuity and progress, we have clearly been paying attention to the wrong signals for systemic health and wellbeing. Perhaps there’s a case to be made that human beings—long and well adapted for the fluctuating and mostly frigid conditions of the Pleistocene ice age—did not respond with such great foresight to the astoundingly enriched and stable conditions of the Holocene. Or the subtle seductions of grass seeds. Or, at least, not where these two things co-occurred.
The next article in this series will explore in more detail an alternate telling of the story of agriculture as a revolution.
Did you know...?
- India suffered extreme locust swarms between 2020–2021, when billions of locusts moved across the northwestern region, decimating crops. They had moved up in an expanding wave that began when unusually rainy conditions in eastern Africa provided conditions for an explosion in the population of grasshoppers. At very high densities, grasshoppers become locusts, voracious eaters and breeders, who seek out farm fields to feed their exponential growth trajectory—until they crash.
- Bamboo and rice cultivation play a role in the regular rat plague events of northeastern India. Mautam (meaning ‘bamboo death’ in the Mizo language) occurs like clockwork every 48 years, when vast acreages of bamboo simultaneously bloom and drop their seeds, carpeting the forest floor with literally tons of ready food for the rats. Within weeks, rat populations explode, going on to devour the maturing rice crops before crashing. Historically, this cycle caused predictable famines across the region, twice every century. The last mautam occurred in 2007.
- The Indian economy proudly boasts an exponential growth rate of 3–8 percent each year, over decades. This reflects rising total consumption driven both by rising population and expanding middle-class consumption patterns. Most of this demand is met domestically, making India’s rate of resource extraction per acre—an indication of pressures on the environment—among the highest in the world. Thus, this growth comes with an equivalent environmental cost, including forest cover, biodiversity, and groundwater attrition; air pollution; soil erosion and exhaustion; freshwater contamination; and solid waste overwhelm.
UNRAVELING CLIMATE CHANGE, FULL SERIES:
- Earth's Changing Climate
- A Planetary Perspective
- Becoming Human: Forged by Fire
- Becoming Human: Shaped by Ice
- The Human Animal in the Circle of Life
- Modern Myths of Prehistory
- Of Mice and Men, Energy and Cancer
- The Agricultural Revolution: An Alternate Telling
- Our Insatiable Quest for Fire
- Fossil Fuels and Modern Myths
- Is There Hope?
- What Can I Do About Climate Change?
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