The Agricultural Revolution is the term used to describe the transition from nomadic hunting and gathering societies to settled agrarian societies. The description deserves some qualification. Taken as a whole, from start to finish, the transition certainly was a revolution in the entirety of changes it brought in the way people lived. Considered over the entire 250,000 year span of human existence, the several thousand years it took was relatively sudden. Still, it did take several thousands of years and it was a gradual and incremental process. The changes in any given lifetime were imperceptible. Cumulatively, over time, they were enormous. For generation after generation, the people who lived through the Agricultural Revolution and made it happen had no idea they were part of anything like a revolution.
Neither was the Agricultural Revolution a singular event. Since the last ice age, the transition from nomadic foraging to settled agriculture has occured independently in at least four, possibly six, separate geographic areas. The transition takes place where both the paleolithic hunting and gathering and neolithic gardening ways of life can co-exist simultaneously. Typically, it is the women who know where and when to gather the local domesticates. Repeated harvestings engage collector and collected in a positive feedback-natural selection process that changes the domesticate species genetically to favour its selection and reproduction. Over time, passive gathering becomes active planting, tending and harvesting.
All the while, as the women acquire the arts of gardening, the men continue to lead the group on their seasonal hunting and fishing migrations. Slowly, as the garden reliably begins to produce a larger and larger portion of the food supply, there is less wandering in pursuit of game and more gardening. The transition to horticulture results in the settlement of villages around the garden plots with hunting expeditions reduced to limited forays from the settled home base. Horticultural villages usually move every few years when the garden soil is exhausted and fresh new plots are cleared.
The central role of women in horticultural societies tends to have political and sociological consequences. It is the women who own and manage their garden plots and pass them on to the next generation. It is the women who decide when their soil is depleted and where the village should move to clear more fertile ground. One of the more interesting aspects of horticultural societies is that it is often women who exercize political power and authority in their society. Anthropologists and travellers alike call attention to the special standing and respect that women enjoy in Austronesian cultures generally and the Philippines in particular. The honoured position of women in Austronesian and Philippine society, more than likely, remains a legacy from their, not so distant, horticultural prehistory.
Horticulture is the critical intermediate step between hunting and gathering and fully developed agriculture. A later shift from small plot horticulture to large field crop agriculture occurs with the introduction of domestic animal power as well as metal working technologies. It is at this stage that agriculturalists can afford to abandon their former hunting ranges altogether and settle permanently in the prime agricultural lands of river valleys with their rich alluvial soils. It is also at this stage, with its heavier field work and animal husbandry, that men take control of the land and animals and resume their dominant position in society over women.
The huge evolutionary advantage of horticulture over foraging as a cultural adaptation is the much increased reliability and abundance of the society's food supply. Horticulture can support a much larger population on the same land as hunting and gathering. Whereas a typical population density for a hunting and gathering society is about one person for every ten square kilometres; subsistence horticulture easily supports five people per square kilometre. That horticulturalists can outnumber hunters and gatherers by a factor of 50:1 has important implications for contact between the two societies. Simply put, in competition for land, horticulturalists invariably eliminate or displace hunters and gatherers.
The distinctively East Asian set of domestic plants and animals, i.e., rice, millet, chickens, geese, dogs and pigs, attest to an independent origin of agriculture in China. Chinese agriculture may have begun in two separate areas. Millet is native to the cooler, drier climate of the Huangho River in northern China while rice grows naturally in the warmer, wetter climate of the Yangtze River in southern China. Whether it started in one area or two, agriculture in China was firmly established by 6,000 BC.