Crop Diversity; Neolithic Foundations for Agriculture's Future Adaptation to Climate Change

摘要

About 10 000 to 13 000-y ago, something fascinating, odd, and absolutely world-changing began to take place almost simultaneously, yet slowly, in Africa, Asia, the Near East, and Meso-America (1). After 200 000 y on Earth as hunters and gatherers, our Homo sapiens ancestors, 500 generations removed from us, began to make a slow, millennia-long transition to agriculture. Why? Over the years there have been many explanations. Some have argued that population growth spurred the need to increase food supplies, which in turn pushed people to farm. But, if you are a hunter and gatherer and in need of food, it is not entirely logical that you plant seeds and wait for harvest time. That is a long time to be hungry. The population-food relationship may nevertheless have played a role. As numbers expanded in groups of hunters and gatherers, subgroups may have split off to migrate to new areas in search of food. On the margins of the natural ranges of the plants they knew and used, they may have found it useful to encourage the growth of such plants, to protect them, to harvest and even to take that last and all-important step of planting the seed they harvested in order to increase the stand.