Dental Asymmetry in a Late Archaic and Late Prehistoric Skeletal Sample of the Ohio Valley Area

Abstract

Dental asymmetry (directional, anti-symmetry, and fluctuating) is analyzed in samples from two prehistoric Native American populations: a terminal Late Archaic population (3200-2700 BP) and a Late Prehistoric population (ca. 750 BP). Both directional and fluctuating asymmetry were found in each sample. Directional asymmetry occurs in only four teeth in the Late Archaic sample and in two teeth in the Late Prehistoric sample. Neither sample exhibits the tendency for opposing arch dominance in directional asymmetry. Fluctuating asymmetry is significantly greater than measurement error for all teeth in each sample. However, contrary to expectations the Late Prehistoric maize agriculturists do not show an overall greater degree of fluctuating asymmetry compared to their forager ancestors. This result coupled with a survey of pathological conditions in these populations suggest that stress levels in Ohio Valley populations, at least that stress which affected dental developmental stability, were not drastically increased with the introduction of maize agriculture. Spearman correlations between relative tooth size variation (coefficient of variation), the magnitude of fluctuating dental asymmetry, and duration of time (per tooth) spent in soft tissue development were obtained for each sample. Coefficients of variation and fluctuating asymmetry are significantly correlated in both samples but fluctuating asymmetry is significantly correlated with duration of soft tissue development only in the Late Prehistoric population.