Archaic Culture-8000 to 500 B.C.
By 4000 B.C., the climate had become similar to that of the present. The area became warmer and the monsoon pattern of precipitation evolved. The megafauna of the past were extinct. People had to broaden their source of food, including many different species of plants and animals. Farming and sedentism began during this period, particularly as corn was brought into the region from the south in the Late Archaic Period. Indicative of this period were one-handed manos, basin metates, flaked tools, and no pottery.