Dermatoglyphic asymmetry as a measure of canalization

Fluctuating asymmetry has been used frequently, especially in the experimental literature, as a measure of developmental stability. However, the relationship between asymmetry and the ability of the genotype to produce an adaptive phenotype is far from clear. In this paper we evaluate the relationship between asymmetry and the mean of a quantitative trait in humans. The trait used is the a-b ridge-count, the count between the a and b triradius in the second interdigital area of the palm. The extremes of both ends of the a-b count distribution exhibit greater asymmetry than values closer to the mean. This evidence suggests that dermatoglyphic asymmetry does reflect to some extent the degree to which the developing phenotype is controlled.