As the Yayoi population increased, the society became more stratified and complex. They wove textiles, lived in permanent farming villages, and constructed buildings with wood and stone. They also accumulated wealth through land ownership and the storage of grain. Such factors promoted the development of distinct social classes. Contemporary Chinese sources described the people as having tattoos and other bodily markings which indicated differences in social status. Yayoi chiefs, in some parts of Kyūshū, appear to have sponsored, and politically manipulated, trade in bronze and other prestige objects. That was made possible by the introduction of an irrigated, wet-rice agriculture from the Yangtze estuary in southern China via the Ryukyu Islands or Korean Peninsula. Wet-rice agriculture led to the development and growth of a sedentary, agrarian society in Japan. Local political and social developments in Japan were more important than the activities of the central authority within a stratified society.