Spatial patterns and evolutionary processes in southern South America: a study of dental morphometric variation

BERNAL V.; GONZALEZ P.; PEREZ S. I.; SARDI M.; PUCCIARELLI H.

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY

Año: 2010

0002-9483

The purpose of this article is to examine the patterns of evolutionary relationships between humanpopulations from the later Late Holocene (1,500–100 years BP) of southern South America on the basis of dental morphometric data. We tested the hypotheses that the variation observed in this region would be explained by the existence of populations with different phylogenetic origin or differential action of gene flow and genetic drift. In this study, we analyzed permanent teeth from 17 samples of male and female adult individuals from throughout southern South America. We measured mesiodistal and buccolingual diameters at the base of the crown, along the cement–enamel junction. The results of multiple regression analysis and a mantel correlogram indicate the existence of spatial structure in dental shape variation, as the D2 Mahalanobis distance between samples increases with increasing geographical distance betweenthem. In addition, the correlation test results show a trend toward reduction of the internal variation of samples with increasing latitude. The detected pattern of dental variationagrees with the one expected as an outcome of founder serial effects related to an expansion of range during the initial occupation of southern South America.