Diagram of American Chronology
... showing regions and eras.
Showing regions: ARCTIC CANADIAN FOREST GREAT PLAINS SOUTHWEST CENTRAL MEXICAN MAYAN COLOMBIAN AMAZON FOREST PERUVIAN SOUTHERN PLAINS SOUTHERN FOREST Eras: Horizon of Recorded History Second Horizon of Agriculture (Humid) First Horizon of Agriculture (Arid) Nomadic Non-Agricultural Horizon Primary Invasion from Asia via Alaska on upper Paleolithic or lower Neolithic, without agriculture, pottery or loom weaving. 15000-10000 BC.