Quite recently I read an opinion in the New York Times with the remarkable title ‘Overpopulation Is Not the Problem‘. In this article the author—a trained ecologist—argues that there is no such thing as a carrying capacity for mankind on this earth. He begins his argument by stating that humans have always altered ecosystems, and thereby increased the planet’s carrying capacity for mankind. Furthermore, the use of tools, domesticating animals for consumption, agriculture and the practice of cooking food to optimally obtain nutrients are also cited as historic examples of mankind using his unbridled ingenuity to increase the amount of resources at his disposal, thus making larger human populations possible. As a biologist myself, I always thought that the actual carrying capacity was a very difficult thing to determine. In fact, as far as I know scientific literature tells us that the actual carrying capacity is pretty much unknown (see for example the research of J.E. Cohen). I was therefore intrigued by this provocative statement and interested to learn on what profound insights and evidence this bold claim is based.
But I am soon disappointed. Because the author then simply begins extrapolating aforementioned historic achievements far into the future, and that’s where it all goes wrong. He begins by writing that the world population now stands at roughly 7.2 billion people, and that by the year 2050 this number is estimated to increase to 9 billion. But then he quotes the United Nations’ estimate that if—and boy what a big ‘if’, in fact it’s so big it deserves to be written in capitals and bold font—IF rich countries invest a huge amount of money in foreign infrastructure, trade, anti-poverty and food security, then the earth will be able to sustain this number. I just have to laugh at this point—just look at the current state of affairs on our planet! Going from that mess to a global end to poverty, universal fair trade, food security for all and nice roads for everyone to drive on in less than 37 years seems to me nothing more than a fancy for naive dreamers. But even if this all did succeed somehow, and I really hope it does by the way, then I still don’t see how that implies there is no final limit to the carrying capacity of our planet.
The article continues by claiming that future improvements in the social and technological systems will probably triumph over limiting environmental factors. But how can anyone be sure of that? How do past successes guarantee future successes? I would say that sounds suspiciously like an economic bubble—or should I say an ecological bubble? And what kind of living standards are we talking about here? What is to be done about the increased risk of catastrophic pandemics, due to the increase in population density? And growing beef for untold billions of people hardly seems sustainable, so must we all become vegetarians? How do we make sure there is enough fish in the sea for an infinite number of people? The whole article seems to entirely bypass the question of what kind of quality of life people will have as the population increases. People are also in this regard nothing like bacteria on a petri dish—just enough resources to survive and reproduce is quite simply not good enough for humans. Beyond the bottom-up factors that limit the carrying capacity, such as food and water, the author also seems to ignore the top-down factors such as infectious diseases. Or is as yet uninvented technology always going to be able to take care of that as well?
Some resources are simply finite, once we use them up they are gone. At the moment, mankind is consuming resources at an unsustainable rate and this problem is only exacerbated by a growing global population. That is an issue our ancestors neither faced nor solved, so simply declaring that we will always be able to find ways to increase the carrying capacity just because our ancestors managed to do so in the past, is patently something no one can say with certainty. Another lesson history has taught us is that putting your faith in science and technology to solve all the world’s problems is not only the height of hubris, but may also have catastrophic consequences for our world, as was for example illustrated in Rachel Carson’s classic book ‘Silent Spring’. We don’t merely shape ecosystems, we also destroy them. So indeed the author is quite right when he concludes the last sentence with ‘…the environment will be what we make of it.‘ The article ultimately makes no reference to convincing scientific evidence in support of its main claim and fails to provide truly compelling arguments to justify such an extremely optimistic and rather arrogant Anthropocene outlook. I think a problem as big as overpopulation deserves better than that.