The role of admixture in the identification of skeletal remains : a metric analysis of Mexican crania

Skeletal biological studies of crania have allowed physical forensic anthropologists to typically distinguish Caucasoid, Negroid, and Amerindian traits for the identification of racial affinity. In the forensic setting, individuals of admixed heritage pose a challenge to the investigator. For example, persons who identify themselves as Mexican have European, Amerindian, and African ancestry. It is the duty of the forensic anthropologist to investigate, morphologically and metrically, where this group may be viewed in relation to the three parental groups.

A sample of 70 Mexican crania was measured from the Spencer R. Atkinson Cranio-Osteological Collection at the University of Pacific School of Dentistry in San Francisco. Data were analyzed by finite mixture analysis and multivariate discriminant function analysis; results were compared to Caucasoid, Amerindian, Negroid, and Hispanic individuals from the Forensic Data Bank at the University of Tennessee-Knoxville.

The results of the study discuss the ability of current metric analyses to properly identify hybrid individuals; specifically the Mexican group from White, Black, and Amerindian populations. Findings show that Mexicans from the Atkinson Collection to be a hybrid group, and can be discriminated from the three parental groups used from the Forensic Data Bank. The Mexican group seems to be most closely related to the Black ancestral component in the Mahalanobis distance scores and the multivariate canonical analysis.