A very wise man (my father) once told me: any practice is sustainable at a certain level. Whether it is driving a gas-guzzling SUV, felling forests for firewood, cultivating industrial monoculture, or burning coal to produce electricity, all such practices would be ecologically sound if there were only, lets say, a few thousand people on the planet. The implication of this statement is that current level of anthropogenic environmental degradation is really just a matter of scale; we could dump toxic chemicals into the rivers and the ocean so long as we remained within certain naturally defined thresholds of those ecosystems to processes and restore.
I will immediately admit that this wonderfully idealized hypothetical situation is riddled with technical flaws, not the least of which is the fact that the most environmentally-degrading practices are not the products of solitary human innovation, but instead contingent products of human history and the aggregation of collective knowledge--hence, they are a function of a large population, not necessarily tied by causation, but still intimately correlated to the processes of civilization and industrialization. In other words, such a hypothetical is almost a ‘categorical error’ in which it almost makes no sense to even ask the question in the first place because the preface automatically nullifies the claim. If we choose to temporarily suspend our overly-analytical reasoning for just a moment, however (please indulge me), the statement does still serve to illustrate an interesting perspective on an important idea: the crux of population as it pertains to sustainability.
The immediate gut-response to the query of ‘over-population’ usually seems to be something along the lines of, “If only, if only there were fewer people in the world.” The outrageous reality that almost 7 billion people currently inhabit the earth is an easy, if not also unhelpful, scapegoat for our current environmental predicament. Surely, such a monstrous population could not be maintained without these environmentally degrading practices, but on the flip side, environmentally degrading practices would not be possible (or necessary) without such a large population--hence my caveat in the previous paragraph. We would not even be asking the question of environmentalism without our enormous population, however, since few of us could or would or should begin making judgement calls about who in our world gets to stay and who has to go, population itself cannot be demonized and vilified too harshly or through such a narrow window. Ultimately, we must accept population size and growth not as a confounding variable to be eliminated at all costs, but as a fundamental element that must enter into the final calculation of our human ecology. To do so, we must first start with the understanding of such a phenomenon.
Phases of Human Population:
Human population has gone through three distinct phases over the course of our roughly 100,000 year history in anatomically modern form. The first-phase, that of prehistoric humans living exclusively as small hunter-gatherer bands, corresponded to low population densities and limited environmental degradation. Humans affected their environment, of course, but no more so than any other naturally, ecologically-bound species. Note: this is an extremely debatable and not entirely accurate statement, but one whose controversy is not entirely relevant to this discussion. It is perhaps more appropriate to say, at least, that pre-agrarian humans were living in a state that was in the most ecological harmony (or minimally, in the least ecological disharmony) with their environment than any of the other proceeding phases in human history.
The second-phase of human population history is defined by the advent of agriculture and the rise of civilizations, a period in our history often termed the ‘biological old regime’. Through time and space, variable manifestations of the agrarian revolution have occurred at multiple instances and at multiple localities, ranging from roughly 8,000-9,000 BC in the fertile crescent of Mesopotamia to approximately 1,500 BC in the Mesoamerica. This phase also corresponds to the rise of centralized bureaucracies, increased population densities (cities) and the general increase in size of the global human population.
The knowledge of domesticating and selectively exploiting natural processes allowed humans to produce in excess of immediate needs, creating surpluses that took our species from living on the brink of constant starvation (the state in which most hunter-gatherers seemed [or seem] to perpetually dwell), to living more comfortable lives in cultures that were more stratified, specialized and permitting of recreational activities. While the first-phase of human history is undoubtedly more representative of our Rousseauian-esque “natural state” or the EEA (environment of evolutionary adaptiveness) for the Homo sapien, it is through the agricultural revolution that most of those things that define us as uniquely human (as in distinct from animals) were able to evolve and flourish.
With the rise of agriculture, we also saw the beginnings (or at least the amplification) of one particular pattern that would soon become the hallmark of the human animal--environmental degradation. The archeological evidence for this is overwhelming, but even in its absence, such a result could be inferred from simply considering the thermodynamic nature of the practice of agriculture. As previously stated, agriculture harnessed the power of natural processes; it mimicked sufficiently the natural state of once-wild plants (and animals, in the case of animal husbandry), to maximize potential thermodynamic output (in the form of consumable calories) with only slightly more thermodynamic input (there is human labor involved--a caloric investment--but in reality, the constant thermodynamic input of the sun does all the real work). This slight disequilibrium tipped the scales in favor of civilization, undermined (at least on a superficial level) the classical frontiers of ecological limitation, and allowed for the rapid expansion of the human population.
The third-phase of the human population is that of industrialization. Everyone has heard the classic story of the steam engine, the steam-powered locomotive, the rise of textile factories in Britain, the genesis of the modern formulation of the capitalist economy etc. etc. What is less well known are the historical/ecological reasons (there are many, but I will reference only a few) that allowed such events to transpire and ultimately set the stage for the greatest population explosion of any large mammal in life’s 3.5 billion (roughly) year history on earth. Note: I am intentionally not considering or evaluating any of the complex political influences for the industrial revolution (the Chinese Opium Wars, the New World silver trade via Spain, British economic protectionism, or competing global markets and industries, specifically in India and the Americas). Again, these are very important factors to the overall narrative of the industrial revolution, however, they are not entirely within the scope of a discussion focusing on the aspects of ecology and population.
Human population was on the rise for millennia as our understanding of the world, our mastery of agriculture and our ability to control certain factors gave us an increasing edge in favor of survival and longevity. After the intellectual renaissance of the Enlightenment, marked most notably by the French Revolution, reason by means of the scientific method became the modus operandi of Western societies. Religion took a metaphorical back-seat and technology thrived, not necessarily as a result, but certainly in congruence. Eventually, one particular technology was developed that opened the flood gates to enormous economic expansion (and by extension population expansion) by providing an energetic well-spring necessary to nucleate the industrial era: the steam-powered engine.
Early designs for the steam-powered engine were so energy-inefficient so as to be completely economically inviable. Huge amounts of lumber were require to generate the heat necessary to create sufficient amounts of steam. Luckily for Britain, and in a huge historical-geological-ecological coincidence, coal was soon discovered as an alternative fuel source. For centuries disregarded as an effectively useless mineral, coal covered large swaths of the British Isles as opposed to once-widespread forests which had been subject to enormous deforestation by the early-1800’s (hence the rapidly increasing prices of lumber in London). Coal was so abundant and so readily accessible at the surface (a geological jackpot) that using it in place of wood to fuel the archaic steam-engines was a virtually free process. By an accident of nature, steam-engine became economically savvy and soon after, the modern textile factory was born.
From here, the trajectory of the industrial revolution is exponential, restructuring culture and society as we know it as a sort of paradigm-shifting juggernaut that is seemingly characterized as much for its monolithic force as for its implications on human population. By interjecting in the epoch-slow process of carbon cycling, humans are able to harness geologically-stored solar energy (thank you Carboniferous period ≈ 350 mya) in a way that short-circuits the thermodynamic equilibrium of the earth. Most people in our overtly machismo and technocratic society would praise such ingenuity as the greatest achievement of our divinely-inspired, or super-natural, or otherwise special and unique species. It is this very aspect of industrialization, however, that is slowly spelling utter disaster for our natural world and our species.
Industrialization is our latest step in the spectrum of learning to artificially outstrip natural resources. Certainly, it would be hard to picture us achieving such a population density as 7 billion worldwide according to the comparatively limited parameters of the biological-old regime. Still, the merits of industrialization are undeniable--increased standards of living, longevity, comfort and an enormous expansion of science, understanding, art and human culture. Of course, these benefits are far form equitably distributed across the globe and while many enjoy the fruits of this latest phase in human history, many others abjectly suffer as a result. In the end, however, despite this inequality, our fates are all intertwined, especially as the level of environmental degradation and ecological disruption has begun to reach critical levels.
So where to we turn with such an ominous prospect? Once again, population appears as a glaringly obvious and tantalizingly easy bearer of the burden that is our self-made lot. But how accurate, how useful is such a verdict? Does this really attack the root cause of our environmental woes? Is the solution to this whole predicament simply a matter of pruning our over-abundant species? The answer is no.
A more honest and holistic understanding of our history and our ecology, I argue, reveals that poverty and disenfranchisement are more appropriately recognized as the ultimate sources of environmental degradation, leading to the proximate factors such as unchecked population growth and large-scale, unsustainable practices. Most technocratic capitalists would vehemently deny this claim, choosing instead to invest their faith and suckle at the teat of the ever-bountiful goddess of human innovation (a little self-righteous, if you ask me), but the evidence to support my position is abundant. Before I explain further, I should say that I don’t mean to purport that if only we could eliminate poverty that our environmental issues would somehow disappear; there are an unbelievable number of other contributing factors to be considered as well. Instead what I am saying (and hoping to substantiate sufficiently) is that the alleviation of poverty, while also an act of justice and a moral imperative, is as well an essential investment in the environmental sustainability and future of our species.