When I was younger, I would occasionally hear from fellow environmentalists that the “real problem” was human overpopulation. (The standard answer, from the well informed, was: nope, it’s inequality, extractive capitalism, institutional inertia, patriarchal values, colonialism, et al. “Overpopulation” was a symptom, not the disease.)
The population-mongers have mostly faded since then, as the “demographic transition” argument has proven itself pretty convincing (people with greater opportunities for a real life end up having fewer children, and more and more countries have taken that path). And as most environmentalists have come to see the role of culture, politics, and economics in shaping our problems.
But I still find it stunning to see a diagram like this one, in a NY Times article from a few weeks ago.
It shows a range of projections of global human population growth, with almost all of them peaking in the coming decades — at 10 billion around 2085 — and then falling way, way down, in fact to below 110 million within a matter of centuries.
According to the author, Dean Spears, who is an economist at University of Texas Austin’s Population Research Center but who is working from data produced by leading demographic studies, “per year births” may have already peaked, as early as 2014, and “peak human population” is expected to be achieved between 2060 and 2090. (I find it hard to believe that we won’t hit 10 billion by 2050. I hope to be around to see.)
From then on, if current below-replacement level trends continue, it’s all downhill. This author projects a potential human population of under 1 billion within less than three centuries of “peak.” That’s one-eighth of today’s population — with no killing involved in getting there (just dying, which we’ve been doing ever since the whole lively ball of life got rolling). (Killing might of course continue, but it’s both a lousy and a stupid way to do things, as it encourages poor decision-making by the survivors.)
The reason this decline could happen so quickly is the same reason why population grew so quickly: it grows, and declines, geometrically. It only takes a certain number of generations for a 3-child-per-couple average (multiplied by the billions of humans around) to spiral out of control. By the same token, it only takes a similar number of generations for a 1.5-child-per-couple average to bring numbers way back down again.
The under 110 million number still seems far-fetched to me. But like the ecological “sustainability bottleneck” that we’re going through, it seems we are also going through a “population bottleneck.” If we get out alive, we may get out quite well. The worry about “Who will work to support all those old people?” in a low-population (but healthy, long-lifespan, and info-rich) world, is a legitimate one. But the author makes clear that if we start planning for a low-population world now, we’ll figure out ways to manage it. And since these trends aren’t deterministic, we could always decide otherwise, or tweak the details to make them workable.
There is, of course, an unstated background assumption to all such population projections. This is the assumption that the world of the coming centuries will be stable enough — and that ecological conditions will remain conducive enough to human survival — for demographic trends like these to be at all predictable. If those conditions go away, then all bets are off.
But the whole idea that we are living through a blip (or spike), a brief historical bubble, is one I find comforting. It’s one that seems true with resource use, and with so much else, too. (I do wonder if the authors aren’t going out on a limb when they write that “Indeed, four-fifths of all births — past, present, and future — would have already happened.” The assumption of a certain life-span for humanity seems, well, let’s say, interesting.)
And even in a worst case scenario, my cosmic argument still applies: that even if we don’t “get out alive,” there are so many other life-harboring planets in the universe that some of them will get out alive from this kind of predicament — a predicament that can be expected from any planet-spanning technological civilization (as Adam Frank has argued) — and that they might share whatever they learn with others. (There’s an assumption in there, too.) Not every experiment succeeds, and not every mutation avoids an evolutionary dead end. But some definitely will. Why else do we even try?
Let us rejoice in difficult blips. They are the background against which peace, contentment, harmony, and creativity become possible.
I don’t find the blip or spike too surprising, although I would have explained, predicted or speculated on such in terms of ecological overshoot and (repeated) social collapses in a limits to growth type manner. Interesting, and I also agree comforting, to see the demographic transition explained/predicted in these terms.
lots of older folks in rich (often White) countries and many young people in generally poor and not so White countries, if we see how that is playing out along the Mediterranean things don’t look so good….
Those ‘Mediterranean’ differentiations are part of the spike… And yes, wars and ‘overshoots’ will likely contribute to the falling off of the spike. I suspect demographers will point to bigger trends like China and now India bringing their living standards up to ‘middle class’ levels, with families getting smaller, etc.
The big question for me is how waves of climate-related migration will play themselves out: whether rich/White countries put up walls and build Gaza-like containment structures, or fight among each other (‘multipolar world’) with migrants contributing to (ISIS-like) stateless people’s armies and scrambling things up, and what happens to nukes and chemical weapons, etc. In the short run, I doubt it will be pretty. But the long-term trends at least look more promising than they used to, no?
Then again, radioactive (and other kinds of) contamination might play a ‘scrambling’ role as well. So it’s still a crap shoot whether humanity comes out ‘intact’ (intelligent, technically savvy, globally coordinated) and capable of establishing a ‘Symbiocene’ type relationship with whatever climate/ecological rearrangements emerge out the other end of the blip/spike/bottleneck…
I think it’s highly unlikely that much in the way of infrastructure (social & physical) will make it thru the social conflicts or the climate changes (and the interactions between the two) see what’s happening now here in the US with power grids, fresh water, migration, labor struggles, etc and how things are already crumbling while the Gov struggles to even get the people in place to keep things where they are let alone become proactive and then crank up the dial…
Hey Adrian,
Yeah, I dunno about the doubters. :^) I usually start all of my env ethics sections with the observation that, when I was their age in the early 70s there were half as many human beings in the world. The fact that the preponderance of energy use and pollution belong to those of us in the 5% of that global population doesn’t mean anything if the goal of the other 95% is to live like middle class Euro/americans. My sense is, increasingly, that nature is going to take care of this for us.
Hi Adrian,
Your contemplation on the trajectory of global human population growth is thought-provoking. The visual representation of projections, indicating a potential peak around 2085 followed by a substantial decline, raises intriguing questions about the future of our species.
Your observation about the demographic transition and the understanding that population dynamics are intricately linked with factors like opportunities for a fulfilling life, cultural, political, and economic contexts is indeed a nuanced perspective. The idea that we might witness a decline to under 1 billion within a few centuries of the projected peak is fascinating, considering the geometric nature of population growth and decline.
The notion of a “population bottleneck” and the analogy to an ecological sustainability bottleneck add layers to the discourse. The call to start planning for a low-population world resonates, acknowledging the need for proactive strategies to manage potential challenges.
The underlying assumption about the stability of the world and conducive ecological conditions for human survival is critical. The recognition that demographic trends are contingent on such stability reinforces the importance of addressing broader environmental and societal issues.
Your cosmic argument, contemplating the potential for life-harboring planets in the universe, adds a philosophical dimension. The acknowledgment of experimentation, potential dead ends, and the persistence of the human spirit to try and overcome challenges reflects a hopeful outlook.
Indeed, as you suggest, difficult blips can serve as a backdrop against which positive aspects of human existence—peace, contentment, harmony, and creativity—may flourish. Your perspective encourages reflection on our place in the vast cosmic tapestry.
Thank you for sharing your insights.