Population substructure and patterns of quantitative variation among the Gollas of southern Andhra Pradesh, India

Population substructure and biological differentiation was studied among th e Golla, a pastoral caste living in the southern areas of Andhra Pradesh (A P) in India, using 11 anthropometric measurements and 20 quantitative derma toglyphic variables. The data were collected from a sample of 334 adult mal es drawn from 30 villages distributed in the Chittoor district of AP who be longed to 8 endogamous subunits of the same caste. Multiple discriminant an alysis of the anthropometrics suggests a highly significant degree of discr imination that is consistent with the microgeographic variations of the gro ups. In contrast, in different sets of dermatoglyphs discrimination is low and generally inconsistent with both the geographic and ethnohistorical aff iliations of the groups. These findings are reflected in the F-ST value for anthropometry, which is more than double the value of dermatoglyphs. The p atterns of gene flow as inferred through the regression of phenotypic varia nce on the distance of groups from the centroid is not generally consistent with the known backgrounds in the case of either dermatoglyphs or anthropo metry. It is concluded that at the level of caste substructure representing the lowest level of population hierarchy, the quantitative variables exami ned here may not portray a complete picture of the historical process of su bdivision. The results of this study are not in congruence with those based on another study of 13 short tandem repeat loci on the same set of populat ions (Reddy et al. 2001), which may provide better insights into the popula tion structure and history of subdivision that are consistent with the know n ethnohistorical backgrounds of the populations.