Interpopulation variation in facial sexual dimorphism: a review with implications for forensic anthropology and...

Understanding how human facial morphology varies across populations and what factors drive these differences is essential for both theoretical and applied biological and medical disciplines. The aims of this study were to: I) outline the dimorphic sex-based differences in facial morphology, II) examine the interpopulation variation in the degree of dimorphism and its potential causes, and III) highlight the significance of this knowledge for medical science.

A systematic review was conducted using the PubMed, Scopus and Web of Science databases from January to March 2025, following the PRISMA guidelines.

Individuals of European and South American origin consistently exhibit a higher degree of facial sexual dimorphism than those of African origin. Additionally, significant differences (p < 0.01) in morphological variation between the sexes have been reported in relation to population size, with smaller or more isolated populations exhibiting less dimorphism. Interpopulation variation in facial morphology is the result of multiple processes, primarily natural and sexual selection. At present, the influence of the natural environment on adaptive or adaptability-based changes in morphology is diminishing, while cultural factors are becoming increasingly important.

Facial morphology and sexual dimorphism data obtained from one population can neither be considered representative of another population nor be used as a basis for developing methods in forensic anthropology. Algorithms that use facial features or craniofacial structures to determine sex should also take biogeographical ancestry into account. Similarly, in aesthetic and corrective medicine, culturally sensitive approaches should be applied to achieve optimal patient outcomes.