Validating Sexual Dimorphism in Finger Friction Ridges (Dermatolgyphics) Using Novel Classifications

Aigbogun et al. in 2018 introduced a new classification with a wide range of application in anthropological research. This study, therefore, evaluated the distribution of finger friction ridges among University of Port Harcourt students; with the aim validating the assumption of sexual dimorphism in dermatoglyphics. The study was a cross-section analytical research involving randomly selected 100 students (49 male and 51 females) from 10 faculties of the University. The dermatoglyphic characteristics were obtained using the protocol of Oghenemavwe and Osaat (2015); as modified by Aigbogun et al. (2018b). The digital dermatoglyphics patterns for the subjects were obtained and the fingers were coded as 1D (thumb) to 5D (little finger); R (right) and L (left). Galton (1988) and Aigbogun et al. (2018a) classifications were used to describe the patterns. Sex-associated pattern distribution, combination, and symmetricity were evaluated using Statistical Package for Social Science (Version 23; IBM® Armonk, New York), and Minitab® 2017 (version 18.1) at 95% confidence level (P<0.05 was taken to be significant). Using Galton's classification, there was no sex-associated difference in the distribution of the patterns except for R_1D (P=0.039). Using Aigbogun et al.'s classification, the distribution of the patterns (L1, W1, A1, AL, AW, and LW) and symmetricity (CS, PS, PAS, with no CAS) was not significantly different (P>0.05). In conclusion, the observed distributional differences in certain patterns between males and females is not an indication of sexual dimorphism, but simply variations. Therefore, to establish dimorphism, group-categorising model must prove at least 75% accuracy for sex discrimination.

Key Words: Dermatoglyphics, Novel classification, Sexual dimorphism, Students, University of Port Harcourt