Society for American Archaeology 57th Annual Meeting, Pittsburgh Coastal Colonies and the Collapse of Tiwanaku:

Abstract: Although the Tiwanaku state (500 AD-1000 AD) is often said to have planted colonies in the coastal valleys of southern Peru and northern Chile, recent systematic survey and excavation in three potential colony sites finds no evidence of Tiwanaku state colonies in the coastal Osmore valley, not even at Loreto Viejo, a frequently cited "colony". Instead, immigrants from the Tiwanaku settlements in the middle Osmore valley moved to the coast as or after Tiwanaku collapsed. Radiocarbon dates, site descriptions, and excavated material support a preliminary reconstruction of the repercussions that Tiwanaku's collapse had on the southern Peruvian coast. In 1985, Elias Mujica confidently wrote that "...it is accepted that Tiwanaku access in coastal valleys was by colonies", citing six respected scholars to support his point. These coastal colonies were presumably established to produce exportable surpluses of coastal crops and marine products for exchange with the highland core of the Tiwanaku state. Whether this exchange was based on "verticality " relations as described by John Murra (1975) or state-level economic strategy, the supposed colonies defined important aspects of our reconstruction of the economics and politics of the late, "expansive " Tiwanaku state