Geographic vectors of human mobility in the Andes (34–36° S): Comparative analysis of ‘minor’ obsidian sources

Abstract

We have carried out long-term comparative in a wide latitudinal range of the Andes (29°–37° south), encompassing selected areas that differ in ecology and biogeography. This latitudinal span shows diversity in subsistence modes across time and space, ranging from Andean agro-pastoralists in the north to Patagonian hunter-gatherers in the south. As part of this research, a program of geochemical and archaeological characterization of obsidian sources and distributions is being developed, attempting to assess connections between different biogeographical contexts. This work has allowed recognizing five Andean sources with different geological and topographical properties. Stemming from this macro-regional endeavor, in this paper we present a comparative analysis of the human use of two sources that, based on the intensity of human use on a macro-regional scale, can be interpreted as ‘minor’ sources. This study is framed on GIS least-cost models for human circulation across rugged landscapes allowing access to the sources. We assess temporal and spatial patterns of human occupation of high-altitude Andean deserts and neighboring areas comparing two of obsidian sources: Laguna del Diamante (34° S) and Cerro Huenul (36° S). The results indicate the existence of asymmetric distributions, particularly in the case of Laguna del Diamante. This evidence is used to assess the existence of dominant geographic vectors of human access and use of the Andean highlands. On this basis, we explore the analytical potential of minor sources for the study of human biogeography and organization of technology.