Dermatoglyphic traits of six Chibcha-speaking Amerindians of Costa Rica, and an assessment of the genetic affinities among populations

Abstract

Dermatoglyphic traits have been used to evaluate population structure and microdifferentiation in several populations. For Chibcha-speaking groups of Lower Central America there are few dermatoglyphic studies, but extensive linguistic, anthropological and genetic data support their historical, cultural and biological relationships. The main objectives of this study were to describe new dermatoglyphic data for six Chibchaspeaking Amerindians of Costa Rica, and to assess the relationships between these and other Amerindian and Eskimo groups, at different levels of population differentiation by means of multivariate analyses of quantitative traits. Sexual (χ2=27.22, df=3, p<0.01), and bimanual (χ2=54.45, df=3, p<0.01) differences were both significant for the overall population, as has been reported previously. Remarkably, higher frequencies of arches, lower frequencies of whorls and lower means of total ridge counts were observed in the tribes analyzed compared with other American Indians. At the lowest level of population differentiation, two Cabecar subpopulations (Atlantic and Chirripo) were compared and no significant differences were found (F=0.001, p=0.72), suggesting that dermatoglyphic variation might not reflect known genetic divergence at this level of association. Comparisons within the Chibchan dataset using Principal Components Analysis (PCA) placed the Huetar and the Cabecar in close proximity, and separated the Guatuso and the Guaymi. Additionally, the Chibchan tribes, although showing nearer proximity to Non-Andean South American groups, can be separated from other Amerindian and Eskimo populations, confirming previous results based on extensive genetic surveys and linguistic analyses that have demonstrated the existence of a Chibchan cluster within a larger South American phylogenetic group. The results obtained support the use of dermatoglyphics to assess interpopulation affinities, even at the level of tribes