Dispersion, colonization and phenotypic structure of prehistoric human populations of the Andes of North-Western Argentina.

Abstract

In this article we study the phenotypic structure, biological relationships and evolutionary factors that acted on the biological diversity observed in the prehistoric groups that inhabited Northwest Argentina (NWA). The collections used belong to different subareas and periods of the development of this region. In this study 15 metric traits of the skull were used. To achieve the proposed objective, models derived from population genetics, multivariate statistical analysis, geo-referenced map and phenotypic correlation between geographical and biological distances were applied. The total genetic divergence (FST) is 16% and within subregions it varies between 2% and 10%. The correlation (r) between geographic and phenotypic distances among all samples in NWA is 0.3 and within subregions it varies between -0.16 (Quebrada de Humahuaca) and 0.7 (Puna de Jujuy). The analysis of georeferenced data indicates two phenotypic gradients in NWA. The results show a varied evolutionary scenario, characterized by an important population structure produced by a set of evolutionary factors (genetic isolation, non-random mating, effective size and different rates of genetic interaction between subpopulations).