Wednesday, April 06, 2005

Malthus was wrong; but we still face a population problem

The famous British economist Thomas Malthus predicted that human population would outstrip food supplies and cause a terrible crash. So far, he's been wrong. Humans keep coming up with ways to increase food supplies. But, does our ability to match food supplies with population growth create other problems that threaten us? This long and complex piece answers yes. It proposes that there is no "technical" solution to overpopulation. That is, we cannot just keep growing even if we can produce the necessary food supply and expect everything to turn out all right. We will destabilize the environment is myriad ways that eventually will lead to die-off. If the solution is not technical, then it must be cultural. But, that's a different essay.

(Via Flying Talking Donkey.)



Cameron said...

Mathus was not 'wrong'; his timing was off. He didn't know about OIL (petroleum) and natural gas. These two massive but finite sources of 'extra' energy postponed (but did not eliminate) the day when the human population would suddenly be much bigger than its post-oil ability to produce food. As soon as petroleum and natural gas are in ever declining supply, so to will be our food production. Lester Brown says that per capita grain production is already falling, and that when we don't have fossil fuels to pour into farm machines, transportation, refrigeration, fertilizer and pesticides, the earth's sustainable carrying capacity for humans will be between 1 & 2 billion people, not the current 6.5 billion that is supported by oil based agriculture. Thus Malthus was right afterall, and this century could be very unpleasant for billions of people.

Jason Godesky said...

Malthus' entire argument was backwards; the question of how to feed a growing population neglects the fact that your population's growing because you have more food!

Now, when something extraordinary happens--like Peak Oil--you can have a Malthusian catastrophe, because your food supply is suddenly ripped out from under you. But Malthus was proposing a systemic problem, and that's not the case at all.

Thanks for the link to my site, Kurt! I really like your blog; I'll be sure to add it to the roll on Anthropik!

Cameron said...

I concede your point, Jason. Malthus did have it backwards; and your way of putting things is born out by the increased food production (plus transportation and storage) empowered by oil and the consequent population increase. Actually, it started earlier than oil with other innovations like the steel moldboard plough which made it possible to open the USA prairies to agriculture where there had been none, or very little, before. So 'new' land was also a factor. Now, however, when the oil prop gets knocked out from under agriculture, our population will be like a cartoon character that has run off the edge of a cliff, and looks down. . .

Bruce said...

Actually Malthus was not wrong, and what he presented was a primordial fact of life rather than the prediction of a catastrophe. He did not predict a crash - he explained the mechanism of misery: famine, war and plague guaranteed by simple mathematics.
He pointed out that, for any living creature, reproduction would cause exponential population increase if unchecked, which would in short order exceed the carrying capacity of any environment - hence that stable states exist because population pressure causes death rates to rise to match rates of reproduction. Both Darwin and Wallace (co-discoverers of evolution) acknowledged that reading Malthus had been crucial to their thinking - revealing the constant lethal pressure which powers natural selection.
What Malthus did not foresee was the abrupt collapse in reproductive rates in all societies where women attain power and education. This has taken the pressure off, and made long and relatively gracious lives possible.