Abstract ID: 3.11782 | Accepted as Talk | Talk/Oral | TBA | TBA

In the topographically complex central Andes, tremendous ecological variation is expressed over relatively small geographic distance. This feature of the environment must have been apparent to the hunter-gatherers who first dispersed into this region of high plateaus, deeply incised valley systems, intervening slopes, and the coastal plain. Here we summarize results from over a decade investigating contemporary Terminal Pleistocene and Early Holocene sites located in the hyper-arid Pacific coastal desert and the high Andes of western South America. These sites are known to be linked by obsidian transfers from the Andean highlands to the coast, but the nature of this connection has been difficult to resolve. By exploring all elevation floors of the western Andean slope and detailed study of archaeological plant and animal remains and lithic artifacts, our team developed fine-grained provenance information to resolve the foraging patterns at these early sites and the interactions between them. The coastal sites have a marked seasonality of occupation, and they are tethered to the interior, based on use of plants and rocks from higher elevations. In contrast, the highland sites could have been occupied in multiple seasons, lack lowland resources, and exhibit a localized foraging pattern above 3500 m elevation. The origins of these distinct coastal and highland adaptations remain elusive, but they are not well explained by simple models positing a tentative and protracted dispersal into the Andean highlands from the Pacific coast. Current evidence allows for multiple migration models for the peopling of western South America. Once established, lowland-highland connections persisted over time in the Andes.