Sunday, December 08, 2013

Agriculture

Even though Lee is tired of arguing with me, I have to get in one more comment on the effect of agriculture on the human race. Domesticating plants and animals (or being domesticated by them) had some obvious advantages for the human race. It allowed us to control far more of the planet's total biological productivity and consequently for the population to expand enormously. Even before the industrial revolution, agriculture probably expanded the human population by twenty to fifty-fold. In addition, the surpluses it created permitted the development of cities, writing, and ultimately, science. Arts gained greatly in sophistication and range. For those at the top of the food pyramid, the gains were great.

How about everybody else? There the record is more mixed. Living in close quarters with our garbage and waste spread disease. Living in close quarters with domestic animals allowed their diseases to adapt to us and spread. Most of the epidemic diseases which plagued humans throughout history (measles, smallpox, etc) are actually domestic animal diseases that spread to humans from cattle, pigs, and domesticated fowl. Periodic flu epidemics still follow that route. Our native diseases, like the common cold, are typically milder - a disease that kills its host tends to harm its own future prospects, so they have become less virulent.

Sedentary living permits women to have more children, since they don't have to carry them about, so agricultural populations expand faster and consequently have higher child mortality. Before agriculture, humans lived in roughly egalitarian bands. Agriculture produced owner and peasant classes, with owners perhaps living better than their forbears but peasants worse.

Studies of the recently existing hunter-gatherers show that subsistence tends to take about three to four hours work per day. Farming tends to take endless toil. The HG life, at least since the sapiens developed sophisticated hunting techniques, was the life of a top predator.

One may ask, "if farming is a worse life than hunting and gathering (HG), why did humans adopt it?" One answer is evolution. Evolution doesn't care if our life is hard, it only cares how many offspring reach breeding age. Another answer is that agriculture was advantageous to those who first developed it, but later not. Once farmers had taken over a piece of land, it was no longer available for hunting and gathering. Greater population density meant that farmers could out compete HGs.

These aren't idle speculations. The archeological record makes clear that HGs were healthier than farmers. They were taller, bigger, suffered fewer stress injuries at comparable ages, and were far less likely to die from disease. This is hardly a Rousseau fantasy - it's the record of the bones. They also appear to have been somewhat less likely to have died by interpersonal violence.