Selective pressures and dental evolution in hominids

Inter‐group differences in tooth size and attrition scores in fossil hominids from the late Riss, Würm I–II and Würm III–IV were compared to determine: (1) the extent and timing of reduction in tooth size; (2) the relation of such reduction to decreased functional demands made on the dentition, as estimated by the severity of attrition. The largest reduction in tooth size was found to take place between the Riss and WAuUrm I–II groups, and to affect anterior teeth as well as posterior teeth. It is suggested that the differences between these conclusions and those reached by Brace ('67) are a function of the samples used. Similarly the observed reduction in tooth size was not associated with any concomitant reduction in functional demands made on the dentition, but appears to have outstripped them, as demonstrated by the increased severity of attrition found in the later smaller‐toothed groups.