It's a nice piece outlining the successive agricultural revolutions that have enabled (or perhaps even been driven by) several jumps in population. My synopsis - there have been three basic revolutions in agriculture: methods, chemistry, and genetics.
- Methods
- 1) the change from hunter-gatherer to sedentary farming about 10,000 years ago;
- 2) the mechanization of agriculture in the 1800's;
- 1) the change from hunter-gatherer to sedentary farming about 10,000 years ago;
- Chemistry
- 3) the discovery of the basic principles of fertilization, also in the 1800's;
- 4) the production of artificial fertilizers in the early 1900's;
- 3) the discovery of the basic principles of fertilization, also in the 1800's;
- Genetics
- 5) the specialized hybridization of corn and cereals in the early 1900's;
- 6) the Green Revolution increasing yields in the 1950's; and
- 7) the current work on genetically modified organisms.
- 5) the specialized hybridization of corn and cereals in the early 1900's;
The Nature piece does, however, have a dark overtone to it in terms of the future, which made me recall the pretty simple fact that raising animals for meat requires more arable land than raising grain for people. It's about a ten-to-one ratio for beef, meaning it takes about ten times as much land to produce a pound of beef than it does a pound of grain. This fact, when combined with the changing diet of the increasingly wealthy Chinese (who are becoming Westernized and consuming more beef), means that if the average diet of China reaches Western levels of consumption for beef, there will be no arable land left on Earth. We are already using half of the available land -- to use the rest of course means getting rid of all of that troublesome forest and jungle.
If you start to consider the "footprint" that Western habits of consumption leave on the environment, the prospect of an increasingly Westernized China is pretty frightening. The alternatives, however, are not too pleasant either. I am not sure I have much confidence in environmental policy under a fundamentalist Islamic world government, or a fundamentalist Jain world government, but I would bet they would not differ much from a fundamentalist Christian view. You would think that the idea of stewardship of the Earth would have formed part of these philosophies, but the geographical areas under this type of political control have shown there was very little understanding of this concept.
Looking at the above list of revolutions, the equation for supply and demand gives fairly simple ideas on what can be altered. Either you increase production (by increasing the area sown, and/or increasing yield/acre) or you reduce demand (by reducing the number of people, or by reducing demand/person). We have concentrated so far on the first part of the equation (production), but the second part has always proved intractable. One wonders what might be possible in terms of genetically modifying humans to require fewer calories?
Arguments are often given that the sea will save us, in terms of increasing the amount of protein available for consumption in the form of fish, either directly harvested, or from aquaculture. Trewavas used two phrases that hit me square in the forehead: "The current malthusian crisis affecting world fisheries has been caused by the application of modern harvesting to an industry that has yet to escape the ethos of the hunter-gatherer." and "...A problem is that fish-farming as currently practised is not sustainable, consuming more fish protein than it produces". That is, that fish protein is not a place to look for feeding needs, as practised currently.
Oh, and the Chinese will all want to drive SUV's too.
