The essence of the proposition that Professor William Rees presents in The Human Ecology of Overshoot: Why a Major ‘Population Correction’ Is Inevitable, is that human population, consumption and pollution have combined to exceed the ability of our planet’s limited ecological systems to sustain it. This situation is not unusual. It has commonly happened in the past with other civilizations, and is a frequent and natural occurrence in all biological systems. Overshoot, then, is just the inability of species to be supported by their environment if they exceed its carrying capacity. This, Professor Rees suggests, is now the condition in which humanity finds itself. Earth is not big enough, rich enough, or regenerative enough to deal with the impact of more than 8 billion people who are hungry, materialistic, wasteful and unrestrained. The result, he suggests, will be a major “population correction” by the end of this century.
This position is supported by Vaclav Smil, a Distinguished Professor Emeritus in the Faculty of Environment at the University of Manitoba. “Without a biosphere in good shape, there is no life on the planet. It’s very simple. That’s all you need to know. The economists will tell you we can decouple growth from material consumption, but that is total nonsense… . If you don’t manage decline, then you succumb to it and you are gone.”
Homo sapiens, like all other species, is naturally predisposed to reproduce and grow in numbers, expanding into suitable habitat until some equilibrium is reached. This requires constraints. In the early history of human civilization, this was disease and the availability of wild food. Despite the benefits of the Agricultural Revolution, population growth was restrained for many centuries by pandemics, the result of large numbers of people living closely together with farmed animals in unhygienic conditions. The slow climb accelerated abruptly in the early 19th century with sanitation and fossil fuels to supplement human and animal power. These changes seemed to suggest that humans were exceptions to the boom-and-bust cycles experienced by other species.
But are we exempt? Despite the congratulatory successes of our Modern Techno-Industrial society (MTI), it is not “supporting” the entire human population, according to Professor Rees. “In 2019, almost half, 47 percent, lived below the US$6.85 poverty line,” and even at this level of success we were over-stressing the fundamental natural structures that we need for reliable ecological and climate stability. Given this statistic, the success of fulfilling all the material expectations of all humanity would seem to be a prescription for a massive environmental catastrophe.
“Baring a nuclear holocaust,” writes Professor Rees, “it is unlikely that H. sapiens will go extinct. Wealthy, technologically advanced nations potentially have more resilience and may be insulated, at least temporarily, from the worst consequences of global simplification. That said, rebounding negative feedbacks—climate chaos, food and other resource shortages, civil disorder, resource wars, etc.—may well eliminate prospects for an advanced world-wide civilization. In the event of a seemingly inevitable global population ‘correction’, human numbers will fall to the point where survivors can once again hope to thrive within the (much reduced) carrying capacity of the Earth. Informed estimates put the long-term carrying capacity at as few as 100 million to as many as three billion people.”
Most of the intricate global interconnections that nourish a modern technological civilization are unlikely to survive. These circumstance largely preclude the continued existence of the culture that we know. Life in mega-cities, or even in cities, may not be viable. In a worst-case scenario, those most likely to survive would be indigenous cultures and those already living in and adapted to rural circumstances.
In summary, Professor Rees writes that, “Global civilizational collapse will almost certainly be accompanied by a major human population ‘correction’. In the best of all possible worlds, the whole transition might actually be managed in ways that prevent unnecessary suffering of millions (billions?) of people, but this is not happening—and cannot happen—in a world blind to its own predicament.”
Obviously, one of the reasons he wrote The Human Ecology of Overshoot was to draw our attention to this predicament so we can take sufficient measures to ameliorate the worst of possibilities. But, do we already know? Do enough of us know? Do enough of us care? Given the rapidity and the extent of the correctional change required, the answer to these questions still seems to be “No”.
While it seems unlikely that 8 billion people or more can be provided with the standard of living to which they all aspire, it might be possible to blunt a possible civilizational collapse with intelligent, cooperative and heroic measures. But we do seem to be racing toward a doomsday. Is its chaos looming ever closer or does it just seem that way because of the complexity and immediacy of our shrunken world? Professor Rees thinks the possibilities are real, and we need to take the individual and collective measures to avoid or be prepared for the unimaginable. We are undoubtedly living in a pivotal moment in human history. It’s important that we know this because the future of ourselves and the entire planet depends on it.
Ray Grigg for Sierra Quadra
Top image credit: Women line up at a feeding centre in Somalia (2017) – courtesy AMISOM Photo/Tobin Jones via Flickr (Public Domain)