Allometric analysis of dental variation in a human population

Abstract

There exists an extensive literature that deals with interspecific allometry, eg, brain size-body size relationships among species. Yet comparatively little attention has been paid to intraspecific or static adult allometry. An intraspecific allometric analysis was conducted on the complete permanent dentition of a prehistoric American Indian population (N = 156). Mesiodistal and buccolingual measurements were logarithmically transformed and regressed on log transformations of femur length, an estimate of body size. When measurements of antimeric teeth were introduced together into common regressions on femur length, 20 of the 32 slopes were significantly different from zero. Thirty-one of the slopes ranged between zero and one and clustered between 0.2 and 0.4. Hence, negative allometry describes the tooth size-body size association, ie, taller individuals in general possess absolutely but not relatively larger teeth than shorter individuals. In addition, no significant sex differences for the regression slopes were observed. Though significantly correlated, tooth size and body size variables are too weakly associated to permit accurate predictions from regression equations. Evolutionary implications of intraspecific dental allometry are discussed.