Sexual dimorphism and population variation in mandibular variables: a study on a contemporary Indian population

Abstract

Sexual dimorphism in a population varies over time due to temporal changes and data on this need to be updated regularly. Further, each population needs its own sex-discriminating anthropometric standards, which can be used on unknown skeletal remains of that population. Sex estimation of frag-mented, buried, or burnt remains in which sex-discriminating morphological traits are often impossible to discern presents a huge problem for anthropologists, archaeologists, and forensic experts. The mandi-ble—a strong bone usually found with other skeletal remains—is considered highly sexually dimorphic. In the current study, we investigated the reliability of mandibular dimorphism for sex estimation using 17 variables in the contemporary Indian population. The study included 385 adult mandibles of known sex and age collected from the two medical colleges in northern India. After the measurement of all variables, they were subjected to discriminant function analysis. All variables showed significantly larg-er dimensions in males except one. The most dimorphic variables included length measurements fol-lowed by height; breadth measurements were the least dimorphic. The gonion–gnathion length emerged as the most dimorphic parameter, with sexing of 79.5%. The stepwise and direct analysis resulted in 81.1% and 84.7% accuracy, representing the mandible as highly dimorphic. Factors that affect sexing accuracy and selection of the best variables are also explored and discussed.