Тариалан хэрхэн эхэлсэн бэ

How Farming Began

AFor most of human history, people obtained their food by hunting animals and gathering wild plants. Then, beginning roughly 11,000 years ago, communities in several parts of the world began to cultivate crops and raise animals. Archaeologists now believe that this shift, often called the Neolithic Revolution, did not happen in a single place and then spread outward. Instead, farming appeared independently in a number of separate regions, including western Asia, China, Central America and the highlands of New Guinea.

BThe earliest evidence comes from the Fertile Crescent, an arc of land stretching from the eastern Mediterranean to the Persian Gulf. Here, wild wheat and barley grew naturally, and people who harvested them year after year may have unintentionally favoured plants whose seeds stayed on the stalk instead of scattering on the ground. Over many generations, such plants came to depend on humans to spread their seeds, a process known as domestication.

CWhy people turned to farming remains a matter of debate. One long-standing theory holds that growing populations had simply run out of wild food. Yet studies of skeletons suggest that early farmers were often shorter and less healthy than their hunter-gatherer ancestors, probably because their diet depended on a few starchy crops. For this reason, some researchers argue that farming was not an obvious improvement, and that the warmer, more stable climate that followed the last Ice Age played a larger role than population pressure.

DWhatever its causes, the change had enormous consequences. Because crops could be stored, farming communities were able to produce a surplus, which allowed some people to specialise in crafts, trade or religion. Permanent villages grew into towns, and within several thousand years the first cities and written records appeared. Stored food, however, also created new forms of inequality, as those who controlled the harvest gained power over others.

EToday, three of the crops domesticated in those early centres – wheat, rice and maize – supply a large share of the calories that humans consume. Scientists who study the genes of these plants hope to learn from the choices of the first farmers, particularly as they search for varieties able to withstand drought and rising temperatures.