TIME AND ARCHEOLOGY IN THE ANDES rcheologists divide pre-Columbian Andean history into periods and horizons. Periods are blocks of time during which individual cultures developed in relative isolation. Horizons refer to eras during which several cultures were united by a common government, religion, and/or art style. The history of the Andes shows an alternation between periods of separatism and periods when a dominant culture expanded to link separate regions under some form of central rule.						2 of 2   Pre-Ceramic Early Horizon Early Intermediate Middle Horizon Late Intermediate The Inca