GEOGRAPHICAL AND ETHNIC VARIABILITY OF FINGER RIDGE-COUNTS - BIPLOTS OF MALE AND FEMALE INDIAN SAMPLES

The graphical technique of biplot due to Gabriel and others is explain ed, and is applied to ten finger ridge-count means of 239 populations, mostly Indian. The biplots, together with concentration ellipses base d on them. are used to study geographical, gender and ethnic/social gr oup variability, to compare Indian populations with other populations and to study relations between individual counts and populations. The correlation structure of ridge-counts exhibits a tripartite division o f digits demonstrated by many other studies, but with a somewhat diffe rent combination of digits. Comparisons are also made with the results of Leguebe and Vrydagh, who used principal components, discriminant f unctions Andrews functions, etc., to study geographical and gender var iations. There is a great deal of homogeneity in Indian populations wh en compared to populations from the rest of the world. Although broad geographical contiguity is reflected in the biplots, local (states wit hin India) level contiguity is not maintained. Monogoloids and Caucaso ids have distinct ridge-count structures. The higher level of homogene ity in females and on the left side observed by Leguebe and Vrydagh is also observed in the biplots. A comparison with principal component p lots indicates that biplots yield a graphical representation similar t o component plots, and convey more information than component plots.