Sunday, December 12, 2010

Biomechanical load and African craniafacial heterogeneity

Generally, physical anthropologists can tell the difference between the skeletal remains of an African,and European. This is due to “extremes” in African craniometrics. Carlson and Gerven observed that the variance in craniofacial features in African populations may be due to diet( See: Carlson,D. and Van Gerven,D.P. (1979). Diffussion, biological determinism and bioculdtural adaptation in the Nubian corridor,American Anthropologist, 81, 561-580.)

The research indicates that craniofacial features, in relation to the skull can be shaped, in evolutionary terms by heritability and high biomechanical load. This is reflected in the morphological heterogeneity within the same population studied by Carlson and Gerven when they studied Nubian craniometrics.

These researchers explained that the differences in Nubian skeletal remains was not the result of populaton changes resulting from invasion. They argued that the skeletal remains represented the same population.

So instead of the changes in the crania African and Black people reflecting biological diffusion, the changes in facial features result from changes in diet that lead to less masticatory stress associated with changes in subsistence patterns . Research shows that changes in diet lead to variation in the size and position of the muscles of mastication which inturn lead to reduction in the robustness of the craniofacial complex. This would explain why the use of multivariate techniques show variability between modern and ancient crania and skulls of African people and the broad or fine features associated with diverse African populations.

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