My friend sent me this op-ed by Erle Ellis, an associate professor of geology and environmental systems at the University of Maryland, Baltimore County, and asked the simple prompt, “thoughts?”. I glanced at the title—“Overpopulation Is Not the Problem”—and took the bait. What I read would have almost made me laugh at its inanity, if it weren’t for the fact that it’s attitudes like the one expressed by Ellis that have allowed 200 species to go extinct today, with another 200 on deck tomorrow. Here is a selection of choice passages from the piece and my response to each:
Many scientists believe that by transforming the earth’s natural landscapes, we are undermining the very life support systems that sustain us. Like bacteria in a petri dish, our exploding numbers are reaching the limits of a finite planet, with dire consequences. Disaster looms as humans exceed the earth’s natural carrying capacity. Clearly, this could not be sustainable.
This is nonsense. Even today, I hear some of my scientific colleagues repeat these and similar claims — often unchallenged. And once, I too believed them. Yet these claims demonstrate a profound misunderstanding of the ecology of human systems. The conditions that sustain humanity are not natural and never have been. Since prehistory, human populations have used technologies and engineered ecosystems to sustain populations well beyond the capabilities of unaltered “natural” ecosystems.
The first paragraph is groovy, but of course it’s just a lead-in, intended to set the stage for the searing indictment of so-called conventional wisdom to follow. But besides the fact that a simple assertion doesn’t count as evidence (I can assert that there will be more bees next year than are alive this year, but it doesn’t make it true), I’d like to highlight the sentence that makes me slap my forehead: “The conditions that sustain humanity are not natural and never have been.” Read that back to yourself a couple of times and let it sink in. The conditions that sustain humanity are not natural and never have been.
It’s clear from the next sentence that Ellis’ point is about humans changing their environment; once people build a mound or irrigate a valley or even clear a footpath through a meadow, the environment ceases to be in its “natural” state. And yes, of course, the argument that humans shouldn’t change the physical characteristics of their habitats is a stupid one, if, for no other reason, than because it’s impossible for humans not to change their surroundings (urinating in a river means it’s irrevocably altered, right?).
Except, no one is saying that humans shouldn’t alter the environment. Indigenous Native Americans lived on this continent for thousands of years, and during that time they burned forests, fished, built structures, and changed their material surroundings in countless other ways (they even had interconnected economies and traded with European powers).
The point we’re making (by we I mean doomers, scientists, rational thinkers, critics of industrialism, et al.) is that there’s a categorical difference between fishing on a river bank with a pole and a string and fishing by essentially raking the ocean floor with a giant mechanical monster requiring the extraction of metals, the shipping of parts, the drilling, refining, and movement of oil, and so on. We could drop a nuclear bomb over the state of Pennsylvania and it would clear a lot of forest. But what could be wrong with that? Humans have always (“since prehistory,” a phrase I’m not sure makes sense) used technology to change the ecosystem, right? (cf. critique of Pleistocene Overkill Hypothesis)
Also note that beavers change their environments by building dams, ants do it by using agriculture to grow edible fungi, birds do it by collecting materials and building nests, etc. And yet we have no problem talking about the carrying capacities of their ecosystems, because carrying capacity relies on natural limits and you can’t escape them, no matter what technology you develop. Beavers can build all the dams they want, but if there’s not enough water for them to drink, their population cannot grow. This is not even Malthusian; it’s just simple logic that should be apparent if you think about what an ecosystem is for more than two minutes.
All technology—even the abstract and ethereal “cloud” where all this data is stored—is made from natural things. This computer is manufactured, shipped, powered, and maintained by natural materials and their storage of energy from the sun. It’s also made by child wage slaves in China, but I digress…
The planet’s carrying capacity for prehistoric human hunter-gatherers was probably no more than 100 million. But without their Paleolithic technologies and ways of life, the number would be far less — perhaps a few tens of millions. The rise of agriculture enabled even greater population growth requiring ever more intensive land-use practices to gain more sustenance from the same old land. At their peak, those agricultural systems might have sustained as many as three billion people in poverty on near-vegetarian diets.
The world population is now estimated at 7.2 billion. But with current industrial technologies, the Food and Agriculture Organization of the United Nations has estimated that the more than nine billion people expected by 2050 as the population nears its peak could be supported as long as necessary investments in infrastructure and conducive trade, anti-poverty and food security policies are in place. Who knows what will be possible with the technologies of the future? The important message from these rough numbers should be clear. There really is no such thing as a human carrying capacity. We are nothing at all like bacteria in a petri dish.
How does one get away with listing the estimated carrying capacities for populations of humans throughout history, and then claim in the very next breath that “there really is no such thing as human carrying capacity”?
No really, how does one get away with that?
Once again, Ellis sets up a nice straw man, as if those who point out the obvious about overpopulation and material limits argue that human carrying capacity can’t be expanded with the use of technology. Of course it can be expanded, and in fact it’s often another piece of ammunition for doomers in arguing against unsustainable industrial systems; the fact that the use of oil has freakishly expanded the carrying capacity of the earth in such a relatively short time is just another strike against it, since the artificially fueled population boom creates and compounds the problems of overconsumption and the over-extraction of resources just to “grow the economy,” which is all that matters apparently.
90% of the large fish in the ocean are dead, when compared to 1950 numbers. Could it be, just maybe, that the feedback loop of a population boom fueled by the use of technology—harnessing the stored solar power in ancient biomatter, in the form of oil—and then the overconsumption necessary to keep the train running, to keep GDP going up every year, which leads to increased population, on and on in perpetuity, is causing people to kill 90% of the fish in the ocean?
Why is it that highly trained natural scientists don’t understand this? My experience is likely to be illustrative. Trained as a biologist, I learned the classic mathematics of population growth — that populations must have their limits and must ultimately reach a balance with their environments. Not to think so would be to misunderstand physics: there is only one earth, of course!
It was only after years of research into the ecology of agriculture in China that I reached the point where my observations forced me to see beyond my biologists’s blinders.
If there’s no drinkable water, we’re all dead, no matter what technology we’re currently employing. I should hope that highly trained natural scientists don’t understand anyone saying anything to the contrary.
The idea that humans must live within the natural environmental limits of our planet denies the realities of our entire history, and most likely the future. Humans are niche creators. We transform ecosystems to sustain ourselves. This is what we do and have always done. Our planet’s human-carrying capacity emerges from the capabilities of our social systems and our technologies more than from any environmental limits.
Yes, humans are niche creators. I’m sitting in a niche as I type this. But carrying capacity doesn’t “emerge from the capabilities of our social systems and our technologies,” it emerges from the material world. Everything comes from nature (from the sun, ultimately)—even our social systems and technologies. The irrigation canals that double a field’s productive capacity for crop yields is a material thing, made with material things, and maintained by material things. The same is true for a dam, a highway system, an economy.
What the technotopians always fail to recognize—some willingly and some by mistake—is that once you reach the limit of those material things, you can’t build the systems or technologies that depend on them any longer. The internet requires material cables and rooms full of servers; talking on the telephone requires cell phone towers and satellites. Natural gas production requires water and oil. Solar panels require metals, which require oil, rubber, other metals, and a huge network of communication and transportation systems in order to extract, refine, mold, and manufacture them.
“The idea that humans must live within the natural environmental limits of our planet denies the realities of our entire history.” What history is Ellis talking about? If humans didn’t have to live within natural limits, they would’ve landed on the moon in 2,000 B.C.E.
What he’s espousing here is at once the worst kind of hubris and the most dangerous and cowardly absolution of guilt: the idea that humans have always destroyed living systems—er, “built niches”—and so dioxin in breast milk isn’t just business as usual, it’s actually a testament to how great we are as a species! We can support 9 billion people on the planet, so take that, carrying capacity conspiracy theorists. Except that, 200 species go extinct a day at the current clip, and no technology is going to reconcile the loss of the honey bee. Human population will crash, like all other populations reaching their material limits. It happens in every habitat—planet or petri dish.