Without permanent kings, bureaucrats or standing armies they fostered the growth of mathematical and calendrical knowledge. In some regions they pioneered metallurgy, the cultivation of olives, vines and date palms, or the invention of leavened bread and wheat beer; in others they domesticated maize and learned to extract poisons, medicines and mind-altering substances from plants. Civilizations, in this true sense, developed the major textile technologies applied to fabrics and basketry, the potter’s wheel, stone industries and beadwork, the sail and maritime navigation, and so on.
