Words

1 April, 2009
(adapted from an essay written March, 2008)

Caring for Capacity
Now for some pessimism, brought to you by basic ecological theory

Fellow humans: are we doomed? These days, doomsday theory is more popular than ever. Is this merely a product of our overblown cyberspace – where every nut job has their say – or is there enough evidence mounting through our experiences on this planet that it is more realistic to buy into a ‘we are screwed’ hypothesis? As a pessimist, I’ve always been drawn to the gloomy truism that says: every species that has ever lived on planet Earth has eventually gone extinct. That is bleak, but what’s worse is that by destroying our planet so, we are doing ourselves in much faster than any species has ever had the lack of sense to do. Unfortunately, I have also studied enough biological, ecological and environmental science to reaffirm my notion that we humans are just passers-by on this rock floating in space – not only us personally, but our species as well.

My pessimism, mixed with the realism that is sought after in the sciences, does make for a depressing set of beliefs. But fear not: our species has a knack for inventing itself out of self-imposed catastrophe (usually after turning a blind eye to the readily-available foresight that would have prevented the calamity to begin with). In this case, who knows if we have the wherewithal to use our brains to save ourselves? Let us hope we do. Just over a year ago, as I drove for days and days across the desolate wastelands of central Australia, I dismally contemplated the possibility of a non-religious human apocalypse. During this time I was reminded of one of my favorite ecological theories, which I believe applies very well to the reality of humanity at this moment in time.

Perhaps due in part to the recent decades of increasing resource use by humans and the resulting environmental degradation, ecologists have developed a concept called carrying capacity. This refers to the ability of a closed ecosystem to support a finite number any one particular plant or animal species. The number of animals in a population of, let’s say, sharks, is dependent upon many factors: water conditions, hunting by humans or other predators, suitable breeding grounds, disease, resource competition, etcetera. Theoretically, if all those factors are constant in a given ecosystem, the major indicator for survival, fitness, and fluctuation of a population is how much food is available. Pretend the sharks’ primary sustenance is a certain variety of fish. When schools of these fish are plentiful the sharks eat well; they succeed in reproduction and their population increases.

In order to keep things balanced, however, nature has developed a way of evening things out. When the shark population becomes too large, their food source is diminished in the form of depleted fish stocks. Then a portion of the sharks go hungry and die and the population crashes. This natural correction occurs because the shark population is above the particular habitat’s environmental carrying capacity for them. Now, assume the only factor controlling the feeder fish population is shark predation. With fewer predators, the fish population recovers and exponentially increases just as the sharks’ did previously. The cycle has come full circle, as the fish are again in abundant supply for the sharks, whose population has in turn begun to increase. The sharks will again decimate the feeder population, securing their imminent cyclical fluctuation. Carrying capacity is nature’s version of ecological checks and balances and it works effectively with all species living in resource-limited, finite ecosystems.

For the most part humans have managed to circumvent the laws of carrying capacity – at least up to this point – by transporting themselves out of low-resource areas via migration, or by growing crops to feed the masses, or by inventing and participating in the technology of trade. Thus, our carrying capacity is not often subject to the micro-ecological influences that regulate most ecosystems. Instead, due to our resourcefulness, humanity has a planetary carrying capacity – a theoretical number of people that the planet can support without becoming so degraded or polluted that humans themselves suffer. Due to progress in health science and technology his number is unknown and easily debatable. In specific ecological zones, though, such as the desert or the arctic, it is obvious that humanity has a low natural carrying capacity. The limited amount of reliable food sources in the arctic and lack of water in deserts limit the size of human populations. Only if food and water are brought from outside the resource-poor system can a population continue to grow.

In all probability we humans have reached far beyond our planetary carrying capacity; far beyond the point where our environment can sustain the population without major detriment. This can be witnessed by the destruction of almost every natural habitat useful to man, a net decrease of food, water, and mineral resources across the globe, and a worldwide rate of species extinction never witnessed before throughout the history of this planet. Meanwhile our population is still increasing exponentially – just like the sharks’ numbers did for a short while as the fish began to run sparse.

For tens of thousands of years the planet only supported a population of a few million humans or less – small groups of nomads, bands of hunter and gatherers, and more recently, primitive sedentary agricultural societies. As far as Mother Earth was concerned this was the way it was supposed to be – a small number of humans coexisted harmoniously with nature and were subject to the same harsh realities that other species face. When the buffalo herd dwindled, the Native American tribes who fed from them began to suffer as well. Many ancient civilizations were in tune with these natural laws, knowing that the destruction of a habitat or species would spell certain death for them too. They moderated their behavior to preserve their existence and the balance on Earth was maintained. However, since the dawn of industrialization and the unnatural over-utilization of resources that has come with it, the human population on Earth has increased several thousand times over, mostly in the last couple of centuries, and it is increasing faster than ever. Needless to say, we are out of sorts with nature’s balance, consuming much more than our environment has to offer.

Since we have, in all likelihood, reached our natural carrying capacity, why is the human population still increasing so rapidly? Well, nature didn’t intend for it but we humans had an evolutionary card up our sleeves called intelligence. Humans are a resourceful and tricky bunch that has been able to use its unparalleled intelligence to thwart the natural law that dictates the survival of all other species. We are the only species that can think logically, better ourselves through science and purposeful community organization, and make unnatural changes to our own environment. Our species has invented and embraced technology on a macro scale and used science and agriculture to improve and extend our lives, and our population has benefited and multiplied. In effect, The Industrial Age, as witnessed by the population graph above, raised our carrying capacity – albeit artificially. Unfortunately, we have been so successful in the unnatural endeavor of environmental manipulation that we have done irreversible damage to the Earth by upsetting the balance in the ecosystems so that the planet will take hundreds of millions of years to recover from the pollution and the lost biodiversity from species extinction and habitat loss after we are gone – if it can ever recover.

In this unnatural manner we have shunned the notion of carrying capacity in the modern world. But we teeter on a slippery slope when it comes to toying with the laws of nature. There was a time when the scientific community believed that our resources were infinite – or that at least our relatively small population had no way of exhausting them anytime soon. Since the 1960s, though, the dubious notions of infinite resources and perpetual human population growth have been under scrutiny by scientists. Evidence has continued to undermine the plausibility of a sustained human population at the bloated levels seen now, especially if these people are to maintain the quality of life (QOL) enjoyed by much of the First World at this moment. It has been shown, via the unfortunate depletion of world resources over the last half century, that the planet’s resources are finite and our consumption of them is at much too high a level to sustain our current population. Simply put: the planet is running out of food and water. In ecological terms we are beyond our carrying capacity and unless we can continue to thwart natural law, our cyclical decrease is impending. Continuing the shark metaphor, it’s sink or swim.

In the past the answer to the problem of resource scarcity was to improve technology. Also in the past, not only did technology have a lot of room for improvement, but there were plenty of untapped resources to use in its development. Unfortunately, this is not the case anymore. Most ecosystems are already pushed beyond their capacity and the bio-rich habitats, such as jungles, have been 90% harvested. Due to over-farming and drought related to global warming, there is increasingly less arable land on the planet. Crop yields are dropping in many areas, and desertification is increasing across the globe. Millions of starving farmers are unable to make a living and are flooding cities, overwhelming the already tenuous infrastructure of Third World capitals. History would dictate that, as in the past, there is an easy technological fix for this destruction. But there are limits to what our technology and knowledge can do for us on a planet with a fixed amount of water and biomass. Regardless of any new scientific breakthrough, we are working in a closed system, and without an influx of resources we are just treading water – and losing ground.

For optimism’s sake let us pretend that humanity once again, over the coming generation, staves off a population crash by inventing new technologies, and that our species continues to grow at an alarming pace. In this scenario we would only be prolonging the inevitable: a significant population downturn. Because no matter what humans do to manipulate the environment with invention, the ecological concept of carrying capacity guarantees one thing: that an exponential increase in any population, human or other, beyond the capacity for the system to support it, will inevitably be followed by a natural, but no-less-disastrous, population crash – eventually. Interestingly, the same technology that humans have used to vault themselves to such a dominant position in ecosystems across the globe is the technology that has so far allowed man to stave off this inevitable crash. Only time will tell if the continuation of this technology will also be able to help us face a less dire population crash. Whether technology can unnaturally soften the imminent blow is yet to be seen.

It is useless to speculate if our population crash, such a long time coming, will follow the model of carrying capacity as dictated by the principles of ecology. This would result in a steep backside of the curve – caused by a horrific environmental collapse due to humanity’s over harvesting of nature’s bounty, and followed by a subsequent population crash, where hundreds of millions would starve to death. Or there could be a more humane, unnatural reduction in the masses, slowed by our careful planning but characterized by a major overall downsize and a decreased average resource consumption per person. Likely, the reality will lie somewhere in between. Through good science, technology, and conservation we could likely soften the blow, but it is important to stress that we have already pushed things beyond the point of no return. There will be a reduction and it is going to be painful to many.

Because roughly 90% of the world's inhabitants are poor, are living in developing nations, and, even now, have access to so few resources, it is going to be those already impoverished who will be most impacted by the crash. With little economic cushion and governmental support, they will suffer greatly. As always, the poor take on the brunt of the world’s problems. But because the deprived use so few resources, a reduction in average consumption in the population of the worlds destitute will do very little to solve the overall problem of diminishing resources. Even hundreds of millions of deaths might not tip nature’s scales in the right direction. The 10% of the world who control most of the resources and live the First-World life, complete with high consumption standards, are the ones who are going to have to downsize the most, on average, when the human population is so large that even technology cannot bail us out. Since the dawn of industry, most First World citizens, by definition, have had a robust economic security blanket protecting us from economic downturn. But when this blanket unravels, the average QOL in developed countries is going to plummet as well. It’s tough to imagine this happening in the USA, as every successive generation has become wealthier and lived better than the previous, save for perhaps the survivors of the Civil War. But that trend is about to change. The sharks are running out of fish.

There is no telling when the average QOL will begin to fall because many new technological advances still artificially boost our success in feeding the hungry masses. But it will happen and soon. Perhaps it’s already begun. Resources are at an all-time low so how can the average quality of life continue to increase? Oil prices reached their historical peak last summer. Fish stocks around the world are so depleted that scientists predict a collapse in the majority of them within the next several years. There are food and water shortages everywhere. Pollution and habitat loss have destroyed much of the third worlds’ arable land. The majority of the world’s virgin forests have been decimated by clearing. The resources, agriculture, and species humans rely on to survive are stretched far beyond their limits. If not in this generation then one very soon, for the first time since the Black Plague of the European Middle Ages, the quality of life for the average human will likely decrease.

The crash will lead to a major QOL adjustment, which will be felt by all but the very richest of society: the economically unflappable and multimillionaires. For the rest of us, this change is going to be very difficult to weather, because while it is easy and convenient to acclimate oneself to a life of steadily increasing luxury, as we Americans have for decades now, it's extremely difficult and painful to experience the opposite. Whether technology, which has both infinitely helped us up to now but also brought us, ironically, to this tipping point, can reduce the intensity of this inevitable carrying capacity crash is only a matter of speculation. For the sake of the human population and the planet we are rapidly destroying, we can only hope so. If not, like the sharks, we will all be swimming with the fishes.