Jeff Guo on grains versus tubers in economic development

Jeff Guo:

[Omer Moav, Luigi Pascali, Joram Mayshar, and Zvika Neeman’s] novel work on archaeological and anthropological evidence, attempts to explain a strange pattern in agricultural practices. The most advanced civilizations all tended to cultivate grain crops, like wheat and barley and corn. Less advanced societies tended to rely on root crops like potatoes, taro and manioc…

the economists believe that grains crops transformed the politics of the societies that grew them, while tubers held them back.

Call it the curse of the potato…

Crops like wheat are harvested once or twice a year, yielding piles of small, dry grains. These can be stored for long periods of time and are easily transported — or stolen.

Root crops, on the other hand, don’t store well at all. They’re heavy, full of water, and rot quickly once taken out of the ground. Yuca, for instance, grows year-round and in ancient times, people only dug it up right before it was eaten…

But the fact that grains posed a security risk may have been a blessing in disguise. The economists believe that societies cultivating crops like wheat and barley may have experienced extra pressure to protect their harvests, galvanizing the creation of warrior classes and the development of complex hierarchies and taxation schemes…

more fertile regions did not necessarily yield more complex societies. The crucial factor wasn’t the amount of food that a society could produce; it was the type of food they chose as their main crop — grain or tuber…

The theory is not ironclad, of course. One problem is that most tuber-growing societies lived in the tropics, where there was also endemic disease that slowed the growth of complex civilizations. Anthropologists also point out that to the best of our knowledge, tubers were domesticated thousands of years after cereals, so societies that grew grains had a head start.

And then there is the case of the Incas, who oversaw an empire that grew both grain and potatoes. The Incas developed a way of freeze-drying potatoes by leaving them out at high elevations. This technology allowed them to treat potatoes like a grain: non-perishable, transportable and taxable…

Bettinger’s research explores an ancient mystery: why people in pre-historic California mostly ate acorns instead of salmon. The fish was plentiful and easy to harvest, and the technology existed to dry and preserve the meat. But for some reason, societies for a long time focused on collecting acorns, which was more time consuming and less nutritious.

Bettinger argues that early societies avoided salmon because it is what he calls a “front-loaded” resource. It takes a lot of upfront work to hunt salmon and turn it into jerky; but after that, the dried salmon is easy to steal (or to freeload off your neighbor). Acorns, on the other hand, are “back-loaded.” A lot of work is needed to turn a cache of acorns into a meal. They are bothersome to steal.

Once the tribes in California became less nomadic, Bettinger and his co-author Beth Tushingham write, more and more of them turned to salmon hunting. Because they stayed in one place, they could better defend their salmon stores.

“It comes down to the ability to expropriate others’ labor,” Bettinger said…

 

If there’s truth in this theory, it would represent a tremendous irony. The potato may have been a curse in antiquity, but it has become a blessing in modern times.

A famous paper by Qian, an economist at Yale, and Nathan Nunn, an economist at Harvard, argues that the white potato revolutionized agriculture in Europe after being brought over from the Americas. It dramatically increased the amount of food that people could grow, particularly in places unsuitable for grain agriculture. Between 1700 and 1900, the world population nearly tripled; Qian and Nunn give the potato a large chunk of the credit…