Tyler Cowen asks, What caused the Agricultural Revolution? and notes that he “long assumed (without much evidence) that mankind invented agriculture about 10,000 years ago because we suddenly, for some reason, became smarter” before encountering this alternative explanation, in Richard Manning’s The Oil We Eat:
It is no accident that no matter where agriculture sprouted on the globe, it always happened near rivers. You might assume, as many have, that this is because the plants needed the water or nutrients. Mostly this is not true. They needed the power of flooding, which scoured landscapes and stripped out competitors. Nor is it an accident, I think, that agriculture arose independently and simultaneously around the globe just as the last ice age ended, a time of enormous upheaval when glacial melt let loose sea-size lakes to create tidal waves of erosion. It was a time of catastrophe.
Tyler Cowen says, “Most of the article is terrible.” The anti-human, anti-farming bias is pretty sophomoric:
Corn, rice, and wheat are especially adapted to catastrophe. It is their niche. In the natural scheme of things, a catastrophe would create a blank slate, bare soil, that was good for them. Then, under normal circumstances, succession would quickly close that niche. The annuals would colonize. Their roots would stabilize the soil, accumulate organic matter, provide cover. Eventually the catastrophic niche would close. Farming is the process of ripping that niche open again and again. It is an annual artificial catastrophe, and it requires the equivalent of three or four tons of TNT per acre for a modern American farm. Iowa’?s fields require the energy of 4,000 Nagasaki bombs every year.
Here is Manning’s primary point, where the title of the piece comes from:
Ever since we ran out of arable land, food is oil. Every single calorie we eat is backed by at least a calorie of oil, more like ten. In 1940 the average farm in the United States produced 2.3 calories of food energy for every calorie of fossil energy it used. By 1974 (the last year in which anyone looked closely at this issue), that ratio was 1:1.
Manning argues that modern Green Revolution farming techniques are not sustainable, because oil energy won’t be cheap and plentiful forever.