The Ups and Downs of Human Demography
by Jason GodeskyToday is World Population Day. 2005’s theme focuses on gender equality, and the need for equal access to education and health care. After all, population growth decreases as education rises. After all, look at Italy; they’re actually facing the problem of their population not growing quickly enough. And by all estimates, population will peak soon, at about 9 billion. No wonder “World Population Day” is re-focusing itself on something like gender equality–overpopulation just doesn’t look like the huge catastrophe all those doom-and-gloom types were saying back in the ’60s. But, looks can be decieving….
Humans are not exempt from basic biological laws. Like every other animal, our population is a function of our food supply. Malthus’ predictions failed, because he set human population as an independent variable. Like so many of us, he supposed that humans have knowledge and free will–that we can choose to reproduce or not, as we see fit. While this may or may not be true on the individual level–I’ll leave the questions of free will and determination to philosophers for now–it is certainly not true on a societal level. If anything, free will makes groups even more predictable: if you decide to be responsible and not have any children, then your neighbor will simply take advantage of the resources you opened up and have six, instead of three.
Like every other animal, we reproduce very quickly to fill up our carrying capacity. The exponential growth curve we saw peaking in the 1960s needs to be understood in those terms. Ultimately, it’s a very simple case of energy in, and energy out.
Every year, there is a certain amount of energy generated by the sun. This energy radiates in all directions, so there is only a small given percentage of it that falls on the earth. The total amount of solar energy available to our planet per time unit has a hard limit–what is called the photosynthetic capacity of the planet. This energy can be used in any number of ways. Plants turn solar energy into sugar; animals turn plant sugar into kinetic energy. Animals can eat other animals, and obtain the energy stored in their bodies, which they obtained from plants, which they obtained from the sun. But none of these conversions are perfect, and some energy is lost in each one; this is why an animal that eats other predators is almost unheard of. Also, each individual likely used some of the energy, before it was taken by the next link in the chain. As animals, we are always at least one step removed–and as omnivores, we’re just as often two steps removed. Also, we’re only one of millions, if not billions of species, all sharing the same, set amount of energy from the sun.
With the agricultural revolution, we found a way to convert biomass into human flesh, by reducing biodiversity in favor of our own foods. We increased the percentage of the planet’s photosynthetic capacity that we recieved. Solar energy that fell on an acre of forest would be divided amongst all the creatures, plant, animal and otherwise, that lived there. Solar energy that fell on an acre of wheat would go exclusively to humans. Our carrying capacity increased; not just that we had more food, but in more abstract terms, we were helping ourselves to more energy. Our population increased, so we cultivated more land. We had more people, so obviously we needed more food. We cultivated more land, and occasionally improved our technology to increase our yields per acre, but more food simply led to more people. Who required more food … the Food Race. But lurking high above our heads was an absolute limit: photosynthetic capacity.
In the 1960s, we saw the latest, greatest “win” in the Food Race: the Green Revolution applied the potential of petroleum to farming, allowing for vastly increased yields. We found a bit of a “cheat” to the natural order in fossil fuels. Now, we can burn through decades of solar energy every day to escape the limits of photosynthetic capacity. Essentially, we burn our past and take credit against our future in order to ensure our continued, exponential growth.
The Green Revolution set our carrying capacity to–well, whatever we wanted it to be. The population responded accordingly, with a huge initial jump, slowing as it reaches its asymptote. The scientists say that asymptote lies at 9 billion, and who am I to disagree? It seems like a perfectly reasonable figure. The population growth curve fits exactly what you would expect for a population adjusting to a suddenly raised carrying capacity–a huge jump, peaking relatively early, and extinguishing as it reaches the new “stable.”
Of course, it’s unlikely that this will remain the case for long. The Food Race goes on. 9 billion people will leave millions–billions, even–starving. Those people need to be fed. We need another “win” in the Food Race!
But 9 billion people is not sustainable. 6.5 billion is not sustainable. There is no sustainble solution for so many people. Only the Green Revolution can feed that many, and the Green Revolution is inherently unsustainable, because it relies on the consumption of a non-renewable resource.
Nor are we even counting our reliance on the rest of the planet. The human race currently consumes some 40% of the earth’s photosynthetic capacity. What will happen–what tipping points will we breach–when we reach 50%? We’re currently seeing massive global climate change and a mass extinction the likes of which the earth has seen less than ten times in its entire history, all propelled by the fact that just one species out of millions is consuming the majority of the planet’s resources.
Population is far from a solved problem. Population is the only problem, and if something doesn’t give, it will very likely mean the end of our species.
Some other missives on the occasion from the Blogosphere, ranging from the insipid to the infuriating:
allAfrica.com: World Population Day Focuses on Equality
CIVITATENSIS: World dePopulation Day!
For a Riot of Reasons: July 11, World Population Day
China CRIENGLISH: China marks World Population Day
PowerBlog: World Population Day
Comment by Jason Godesky — 11 July 2005 @ 5:27 PM
“We need another “win” in the Food Race!”
We’ve done it!
http://english.aljazeera.net/NR/exeres/83C43DC5-EB8F-4504-A9D3-4E25CE6B7F05.htm
Problem solved!
Comment by Cory S. — 11 July 2005 @ 5:42 PM
Jason,
I have to say, you bring a fresh perspective to the issue. Very well written. It would have been great if you addressed the “What can we do?” instead of wondering “What will happen?”
Just out of curiousity, where does my article (July 11, World Population Day) stand? Is it Insipid or is it infuriating ?
…for a RIoT of reasons
Comment by One More Reason — 11 July 2005 @ 8:41 PM
Well, what CAN you do? We’ve far outgrown our carrying capacity, civilization is determined to expand at any cost (and the costs will be huge) and even if we suddenly decreased our reproduction rates, our population would continue to increase for a while. Also, the estimate of 9 billion people is predicated on the Third World becoming like the First World, which is somewhat impossible. There simply are not enough resources on this Earth or 3 earths or 6 earths for that. If everyone were to live like people in America do, the number of Earths we’d need to support that is something like 8 or 9.
There might be some possibility for a managed collapse, but I don’t think there is much chance of that happening. Perhaps if we’d started a long time ago, we could have managed a collapse. The way I see it now, we’re due for some very hard times. We can’t rely on the people in power to protect us any longer, because, well, the-powers-that-be have generally sucked at providing for or even understanding the needs of the majority.
People might say this is a defeatist attitude, or that I’m pessimistic about the future, but I’m not. I just don’t think the status quo is going to be able to continue on a worldwide, systemic scale. And if we look deeply at the status quo, we’re able to recognize that it’s not exactly the greatest thing for the overwhelming majority of people on this planet. We don’t need to wait until our population reaches 9 billion starving in order to have billions starving, we’re already at the 2 billion mark. What will the number be when the available resources are even more spread out? I can’t imagine the continuation of our systems ever turning out to be a positive thing for anyone but the elite.
From this, I’ve come to the conclusion that we CAN’T “save the world”, because the world is saving itself. No animal can continually expand its carrying capacity. We’re due for some pretty ugly balancing in the future. I’ll be doing the best I can to help on a local/regional level, but I don’t have the ability/power/knowledge/motivation to save our civilization and its staggering number of people.
For now, I’m learning/hoping to become self-sufficient, and hoping to create an ecovillage/sustainable community off of the grid. I just hope that I have enough time before Peak Oil, Water (and other resource) wars, pandemics, global warming, and many other coming disasters make it impossible for me to do so. To everyone out there, I suggest you do the same.
Peace,
Devin
p.s. There is always the question “What if the crash doesn’t happen?”. Well, if something this infinitesimally unlikely happens (I won’t call it a “miracle”, because I’m not sure that NOT having a collapse is a good thing) you’ll still be in a peaceful, self-sufficient, balanced community. There are so many reasons to move to a community like this, that our current way of life is ending is only one of the factors. Not very many people are happy with their life in this system — and I mean really, truly happy. I think a movement of decentralization and re-localization is good all around.
Comment by Devin — 11 July 2005 @ 9:17 PM
Actually, Reason, yours was the only one that didn’t aggrevate me. Sorry to get you lumped in like that….
I’ve been working on an “official” series of articles outlining my thinking on this, so this particular article was just a small detour (hence, a rough outline of our problem, with no solution offered up), but my thinking on it comes down to this: we’ve been in a very deterministic escalation for some ten thousand years, and it’s now coming to a head. There was never any real way to get out of it except by expanding more–until now. We’ve now reached a point where we, individually, can choose a different, more fulfilling life for ourselves. The catch is, the very reason this is possible for us individually, is because we’re reaching the limits of our expansion, and because there is no future for us as a group. We’ll be looking at total civilizational collapse–Chaco Canyon on a global scale. The silver lining to this is even though there’s probably no way to avoid catastrophe on the macro scale, that same catastrophe provides each of us on the micro scale the possibility for a better way of life, the likes of which none of our kind have known for a dozen millennia.
Comment by Jason Godesky — 11 July 2005 @ 11:51 PM
Devin:
I agree with what you’ve said, but there is one huge-and-growing hitch….
Suppose we have a sustainable community set up. We have a landbase which provides all our basic resources; crops, fresh water, etc, etc. Then the crisis comes, and most of the rest of America/name the country is s. What’s to stop the government from noting “Oh here’s a bunch of land we could be farming, mining, clearcutting, or getting some freaking water from. Why don’t we go and steal it?” Thanks to the recent Emminent Domain ruling: nothing! And in fact I’m nearly certain this is exactly what’s going to happen.
I don’t mean to be pessimistic, I’m just genuinely freaked-out by this. The only solution I think is to lay low for the initial period of the collapse, and only claim a piece of ground once the government has ceased to be operable. But at that point everyone will be rushing to do the same–and where does that leave us?
Comment by Steve Thomas — 12 July 2005 @ 6:33 PM
With a lot of accumulated expertise to start over again elsewhere, further than most people will be willing to stray from the cities? I’m just desperately trying to find silver linings these days.
I wrestle with the same dark thoughts, about the possible futility of escape, since it’s impossible to predict when and how it will all go down. For example, I saw a documentary on Tierra Del Fuego a while ago and the people living there by the beach seemed to have it so good. But who says that thanks to climate changes or nuclear detonations over the pole, etc., that even a remote paradise like that may not simply disappear under rising waters.
It’s useless to try and predict everything. In the end total randomness might be the one and only judge of who gets to stand.
Comment by Gerard Godin — 12 July 2005 @ 11:15 PM
Nothing remains the same for long. I’d agree. It has long been the problem that people assume that tomorrow will be like today when it comes to population. But it will not. The world is not coming to an end. It used to be that religious loonies alone held these beliefs. Now, those who claim to be scientists are proclaiming similar obscurantism disguised as “science.” You assume, for example, that having children is irresponsible (”if you decide to be responsible and not have any children”). Genetically, that’s nonesense; genetically, it is the opposite.
As far as resources, all things being equal, a family of 10 in North America is far more efficient than a family with only three. It’s far more efficient to heat and illuminate a house for 10 people than a house of the same size with only three people. And the same applies to almost everything else. A minivan with a family of 7 is more efficient than two families (let alone three) with as many people, not only in gas consumption but in terms of insurance, repairs, and so on. Large families are typically not as wasteful, and make a far more efficient use of resources. Those with no children are typically less efficient, tend to be more highly consumeristic of trinkets and less necessary things. Unfortunately, these days it almost takes a rocket scientists to realise that consumerism is more harmful to the natural environment than the number of people per se. Again, typically, no domestic arrangements are more inefficient and wasteful than a DINK arrangement –not to mention the genetic inefficiency.
Fortunately, no matter how many Chicken Littles with a science background appear or how many apocalyptic announcements are made, people will have kids, and probably more of them. That’s the biologically-correct thing to do. BTW, you folks may be helping the population “explosion” with the silly doom talk. There is evidence, as you know, that creatures tend to reproduce more in socially/environmentally threatening situations. If you keep repeating the mantra and manage to convince many of them that the end of the species is at hand, paradoxically, creatures will do the rationally foolish (from your view) but the biologically imperative thing.
Comment by Someone — 9 August 2005 @ 12:30 PM
Population growth has never, and will never, be constrained by ideology. For all our self-congratulation on how we can choose how many children we have–and as true as it may be on the individual level–our overall population has always–always–matched our food supply. Because biology wins out over reason, every time. So we can’t get more people to reproduce, and we can’t get less. Only our food supply can do that. I used the term “responsible” that you object to so much to illustrate that. If we ask people to be “responsible” and have fewer children, it will simply result in the “irresponsible” having even more children.
Efficiency is not the problem at all. Naturally, lighting a house for ten is more efficient than lighting a house for five. The problem is one of absolute limits. There’s only so much energy available to us, and the more we take up, the less there is for everything else on the planet. So if we’re all hyper-efficient with our ten children, and they all grow up and have kids so there are ten times as many households in the next generation, all equally efficient, then the current mass extinction will claim us and end our species, simply because at that point we’ll be taking up more than 50% of the total energy capacity of the earth.
It doesn’t matter how efficient we are–if it’s one person using it all up, or billions splitting it so many ways. What matters is how much total energy we require. Even at the most minimal basics of human existence, there isn’t enough for 6.5 billion sustainably, much less 9 billion. That’s not even considering the incredible luxury of the first world.
As I’ve said before, apocalypticism is a mode of human thought as old as civilization itself. It’s an archetype. We are preceded by others who based their predictions in religious scripture, and were proven wrong. To indicate that we have placed our facts and evidence into a well-worn model proves only that we are human, and think like humans. To allege that we’re wrong because others made similar claims in the past and were wrong is illogical.
Comment by Jason Godesky — 9 August 2005 @ 1:58 PM
Someone,
You should avail yourself of the work done by Virginia Abernethy. Her economic oportunity hypothesis suggests just the opposite of what you assert.
Sincerely,
Paul
Someone wrote
BTW, you folks may be helping the population “explosion” with the silly doom talk. There is evidence, as you know, that creatures tend to reproduce more in socially/environmentally threatening situations. If you keep repeating the mantra and manage to convince many of them that the end of the species is at hand, paradoxically, creatures will do the rationally foolish (from your view) but the biologically imperative thing.
Comment by pbj@email.unc.edu — 19 September 2006 @ 1:06 PM