Past Human Mobility Corridors and Least-Cost Path Models South of General Carrera Lake, Central West Patagonia (46° S, South America)

Abstract

Understanding the use of natural corridors is critical for characterizing the past use of marginally occupied landscapes at the Andean fringes of western Patagonia by the hunter-gatherer groups who inhabited this region. In this paper, we combine least-cost path models and archaeological surveys and excavations to determine the possible movements along the southern margin of General Carrera Lake. The methodology includes defining uncertainties that allow for modeling a set of equiprobable routes, thereby avoiding problems with errors and biases from predictors, such as slope, land-use cover, and seasonality. The results identify mobility corridor bottlenecks, i.e., geographical areas with a high probability of travel routes with equiprobable routes that converge. In addition, we identify areas where travel routes are likely to diverge into multiple semi-parallel routes. The study of archaeological sites provides stratigraphic data to control for the chronology and characteristics of mobility along this transect. The correlation between archaeological sites and paths, specifically for the control and winter scenarios, shows the quality of these route predictions. These results indicate the repeated use of internodal spaces that were effectively incorporated into mobility during the last three millennia.