Jeff's Lunchbreak

Guns, Germs, and Steel: The Fates of Human Societies is a Pulitzer Prize winning book by Jared Diamond. To quote from the book itself, it is "A short history about everyone for the last 13,000 years." Diamond has attempted to explain why world history has taken the course it has. But he's more interested in large scale trends and causes, as opposed to battle by battle or even war by war tracking of history. Or, to put it another way, he was taking a more scientific approach to history, as opposed to just stamp collecting. Wikipedia has a good overview of the book, so I'll only present a brief summary here.

To use an example, we all learned in school of the European conquest of the Americas, even though the Europeans were vastly outnumered. We've been taught many of the factors that lead to that result, most notably the superior weapons technology of the Europeans, horses, and the diseases that Europeans brought with them. Diamond noted all these proximate causes (and a few others), but then moved on to ask why the Europeans had developed those advantages, and not the other way around. Why hadn't Motecuhzoma sent ships to conquer Spain?

According to Diamond, much of the advantage of certain regions was a result of geography and the indigineous plants and animals. To help support his case, Diamond looked at native plant species around the world, how nutritious they were, and how easily they could be domesticated. Wheat, for example, is a very nutritious crop, with a fairly high protein content for a plant. It required only a single mutation in wild wheat, inhibiting the seeds from falling off the crop when ripe, to make it suitable for agriculture. Teosinte, by comparison, required many more mutations to become domestic corn (maize), which isn't as nutritious as wheat. As it turns out, Eurasia has a greater number of nutritious, easily domesticated plants than any other region.

Eurasia also had a higher number of potential livestock candidates. In many regions of the world, the Pleistocene extinction event killed off most large mammals at the end of the last ice age (there is debate over the cause of this extinction, but that's largely irrelevant to Diamond's hypothesis). If you don't have large wild mammals, you can't domesticate them into livestock. But you can't just domesticate any large animal. In this section of the book, Diamond quoted Tolstoy, "Happy families are all alike; every unhappy family is unhappy in its own way." There are many traits an animal has to have to make it suitable for domestication (diet, behavior, lack of aggression, social structure, etc.), but missing any one of them would make an animal unfit for domestication. Diamond used this reasoning to show why, for example, zebras weren't domesticated in Africa like horses were in Eurasia, or why bears or rhinos weren't suitable to domesticate for food or as draft animals.

Diamond went on to argue how differences in geography allowed agriculture and domestic animals (referred to collectively as food production) to spread more easily in some regions than others once they had been developed. Eurasia, without any great barriers such as deserts, and with an east-west axis that meant the climate was more similar along its breadth, facilitated this spread more so than other regions.

Once regions had developed food production, they could maintain higher population densities. Initially this gave them a military advantage just through shear numbers. But eventually, by providing for an artisan class that didn't have to grow its own food, it led to technological advantages, as well. The high population densities, along with domestic animals, also contributed to those regions having endemic diseases that didn't exist elsewhere.

As an example of how Diamond was attempting to explain the grand patterns in history over tens of thousands of years, he pointed out that someone could ask why, out of all the areas of Eurasia, Western Europe currently dominates the world stage, and not Eastern Asia. He stated that this simply might be a short term 'blip', and not part of the long term trend (just look at the resurgence of modern China).

As I said, this is only a brief summary of the book. Diamond had many more reasons and examples that he used to support his hypothesis.

Some parts were more convincing than others. It also didn't help that in a few examples he brought up that I already knew a bit about, I saw some mistakes. For example, when discussing ancient human history, he compared the Out of Africa hypothesis to the multiregional hypothesis. The weight of evidence strongly favors the 'Out of Africa' hypothesis, but Diamond seemed a little more ambiguous in the book. In another section, discussing why cultures might be resistant to adopting certain technologies, he brought up the old QWERTY/DVORAK controversy, claiming that DVORAK is clearly superior to QWERTY, but market forces have kept it from being adopted. This is an old urban myth that isn't true. There haven't been many actual studies comparing the two keyboard layouts, and the studies that have been done don't show a very big advantage of one design over the other (certain advantages of each layout are offset by different advantages of the other layout).

Overall, I thought the book was very interesting, and that Diamond did a good job of presenting his case. I'd definitely recommend it.

Update 2010-03-29 - Slightly revised wording in 4th from last paragraph.