320 economy: Asia and the Pacific and ensured regular economic and cultural contact among the various urban centers of Asia The Spread of Settled Agriculture Medieval Asian and Pacific societies benefited from ample and freely available productive land that supported the basic economic needs of the region, which was generally underpopulated before 1500 Asians and Pacific islanders moved from less fertile to more productive unoccupied areas by foot or boat; they also migrated as the result of natural catastrophes (such as volcanic eruptions and earthquakes), prolonged unfavorable weather conditions, environmental or geological change, or to avoid contact with other mobile and potentially hostile populations The geography of the region is diverse The several dry and less fertile zones included China’s Gobi Desert, southern Asia’s Thar Desert, and the many desert regions of Australia; the rugged mountainous regions, such as the Himalayas, that surround the northern borders of southern Asia; the sparsely settled volcanic Southeast Asian and Pacific islands where mountains and jungle coincide; and the substantial grasslands of central Asia and Australia, where there was a pastoral tradition and where meat and milk products, rather than grains, were dietary staples Before the medieval era the rich alluvial soils of the Indus, the Ganges, and the Yellow River plains of northern India and northern and central China had sustained the transition from upland shifting to settled, lowland cultivation This move was supported by new technology, such as improved tools, better water management, and a sense of seasonality, which included the use of a calendar; all these improvements allowed farmers to cultivate lands that had been useless swampland or that had been subject to heavy annual flooding By the early medieval era settled and increasingly populous village societies in other regions of Asia were cultivating millet and other traditional grains The traditional Asian productive units were family centered and based in a village The Chinese village was a collection of traditional extended-family households that consisted of the male family head, his wife, their children, his parents, and his brothers and their wives and children Japanese village households were nuclear, consisting of the male head of family, his wife, their children, and his parents Brothers established branch households by clearing new lands or by colonizing frontiers The other regions of Asia and the Pacific had local variations of these Wet-rice cultivation became common in Southeast Asia, central and southern China, coastal southern Asia, the region of present-day Sri Lanka, southern Japan, and southern Korea from 500 to 1000 c.e Initially in the areas of modern-day Thailand, Cambodia, and Vietnam wet-rice seeds were dis- tributed at the beginning of the monsoon season on a plowed floodplain that had been divided into small fields bordered and contained by elevated earth The rice seedlings matured after the terraced fields annually flooded with the water of monsoon-swelled rivers and lakes The wet-rice crop grew quickly and needed little work, and it was harvested after the floodwaters receded Other regions of Asia adapted a more labor-intensive transplanted seedling method that was developed in the Cham regions of today’s central and southern Vietnam in the first centuries c.e In contrast to the broadcasting method, seed was annually sown in small, flooded seedling beds before rather than at the beginning of the rainy season While seedlings took root, farmers and their families prepared nearby terraced fields; they weeded and broke up soil with wooden, stone, or metal-tipped hoes until the monsoon rains soaked the earth Seedlings then were transplanted by hand with enough space between them for each plant to grow In the wet-rice regions of Asia there were three food staples: rice, fish, and coconuts Rice might be affected by periodic disease, rodents, and insects Fish (from the ocean, rivers, flooded rice fields, or fish farming in water-storage tanks) and coconuts, however, were virtually free of pests and diseases Fish usually was dried or fermented and was the major garnish to rice Properly prepared, rice and fish could be stored for more than a year Coconuts (the source of fruit, sugar, oil, and palm wine) could not be stored as long but were available at three-month intervals Most people ate rice, whether dry or wet, in preference to other grains or starches Reliance upon other staples was socially unacceptable except during rice famines, when rice cultivators could normally turn to root crops (such as taro and tapioca, which were grown as supplemental crops in wet-rice areas) and yams (which were gathered from nearby forests or were cultivated in rain-fed fields) Sago palms were another alternate source of starch During the dry season local populations grew a variety of vegetables such as beans, tomatoes, and peppers Early Asian rice cultivators also supplemented their diet by networking with highland hunters and gatherers, in part to negate the highlanders’ potential to raid their productive villages but also to exchange their diverse agricultural produce for meat and forest products, such as wood, bamboo, and tree resins Despite potentially high productivity, with the exception of China urbanization in the early wet-rice producing regions was unusual In part this was due to cultural preference, the geographical isolation of the productive regions, the intensive communal labor commitments of wet-rice cultivation, and the seeming lack of need for supralocal political commitment