What happens when we run out of people?

This isn't a particularly topical question, considering that the world population spiked past seven billion, and will hit eight or nine billion in my lifetime.

In the long term, it is an interesting question. It's one that rich western countries are already facing to a certain extent, and we have plenty of short-term answers, but few long-term ones.

This is the issue in a nutshell: in most of human recorded history, life was a Malthusian mess. People had no reliable birth control.

Beyond that, most families didn't want to stop having kids, because most people were dung-smeared peasants, and kids are handy, free farm labourers/load-bearing animals/emergency rations during the next famine.

So families had as many children as they could feed, give or take child mortality.

Then we got the industrial revolution and antibiotics and the green revolution, and all of a sudden, all those kids were still being born, but they weren't dropping dead of dysentery like all your party members in Oregon Trail. They lived, and they moved to the cities.

But something weird happened, something people didn't really notice for decades. When people move to cities, when they take part in modern industrial and post-industrial societies, they have fewer kids. In fact, the more advanced, the fewer kids.

The total fertility rate in Canada right now is around 1.59. That means that the average woman in Canada will have 1.59 kids in her lifetime. To replace every person still alive in Canada would require women in Canada to have about 2.1 kids. (The 0.1 is to account for people who die of crime, disease, or accident before having any kids of their own.)

Canada's population is still going up because we have a lot of demographic momentum from the baby boom years, and because we are a friendly and open society that welcomes immigrants, especially if they have money and marketable skills.

Canada actually has a fairly high birth rate. Singapore's is 0.78. Japan is at 1.39, South Korea at 1.23.

Right now, there are racists and wackos out there who like to use stats like this to stir up panic. Look, they scream, not enough white Euro-babies are being born! We'll all be eaten by those scary brown people from the countries at the top of the fertility rate charts!

Which is stupid, because one of the hallmarks of being a national basket case is, in fact, having a stupendously high fertility rate. When Niger or Mali or Uganda solve their problems, when they build the kind of education-industrial-technological infrastructure necessary to make them a real power in the world - their birth rates will drop like a rock.

And that's the big question. If we save everyone, if Bob Geldof and Bono bring Africa up to First World standards of wealth, and China and India finish their projects of becoming powerhouses, then every population starts shrinking. Estimates say it'll start happening sometime around 2050, give or take.

So the question is this: we have created the modern city (yes, including suburbia) the most pleasant and safe place humans have ever lived. But to live here is expensive, and we react to this by having fewer children, who are also pricey. What do we do in 2050, when we run out of people to replace us, to run the cities and feed them? Do the costs of living in an urbanized world eventually destroy it utterly, or can we hit that 2.1 sweet spot?

Don't worry too much, though. It'll be a problem for our great-great-great-grandchildren. Assuming we have any, of course.

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mclaxton@langleyadvance.com