1491_ New Revelations of the Americas Before Columbus - Charles C. Mann [170]
Manioc has always been the Amazonian staple. To this day, it is ubiquitous in the slash-and-burn plots that surround every riverside hamlet. These little, shifting farms look like unchanged remnants of the past. But that idea apparently is mistaken. Rather than being the timeless indigenous adaptation portrayed in ecology textbooks, many archaeologists now view slash-and-burn agriculture as a relatively modern technique whose spread was driven by European technology. The main reason is the stone ax.
Living in the world’s thickest forest, the inhabitants of the Amazon basin had to remove a lot of trees if they wanted to accomplish practically anything. For this task the stone ax was their basic tool. Unfortunately, stone axes are truly wretched tools. With a stone ax, one does not so much cut down a tree as use the ax to beat a section of the trunk to pulp, weakening the base until the tree can no longer support itself. In the outskirts of the central Amazonian city of Manaus, a researcher let me whack at a big Brazil nut tree with a locally made replica of a traditional stone ax. After repeated blows I had created a tiny dent in the cylindrical wall of the bole. It was like attacking a continent. “Those things suck,” the researcher said, shaking his head.
In the 1970s Robert Carneiro, of the American Museum of Natural History, measured the labor required to clear a field before the advent of steel. He set people to work with stone axes in thickly forested parts of Peru, Brazil, and Venezuela. Many of the trees were four feet in diameter or more. In Carneiro’s experiments, felling a single four-foot tree with an indigenous stone ax took 115 hours—nearly three weeks of eight-hour days. With a steel ax, his workers toppled trees of similar size in less than three hours. Carneiro’s team used stone axes to clear about an acre and a half, a typical slash-and-burn plot, in the equivalent of 153 eight-hour days. Steel axes did the job in the equivalent of eight workdays—almost twenty times faster. According to surveys by Stephen Beckerman, an anthropologist at Pennsylvania State University, Amazonian slash-and-burners are able to work their plots for an average of three years before they are overwhelmed. Given that farmers also must hunt, forage, build houses and trails, maintain their existing gardens, and perform a hundred other tasks, Carneiro wondered how they could have been able to spend months on end banging on trees to clear new fields every three years.
Unsurprisingly, people with stone implements wanted metal tools as soon as they encountered them—the prospective reduction in workload was staggering. When Columbus landed, according to William Balée, the Yanomamo lived in settled villages in the Amazon basin. Battered by European diseases and slave raiding, many fled to the Orinoco, becoming wandering foragers. In the seventeenth century they acquired steel tools, and used them to make the return journey from seminomadic hunter-gatherers to agriculturalists who lived in more or less permanent villages. So precious did European axes become during this time, according to Brian Ferguson, an anthropologist at Rutgers University, that when a source appeared the Yanomami would relocate whole villages to be near it. Steel tools, he told me,