Anterior dental cutting in the Laetolil hominids and the evolution of the bicuspid P 3 Research supported by a University of Michigan Rackham grant.

Abstract

The younger Laetolil hominids provide evidence of a unique anterior cutting complex with a chisel-like action occurring between the lingual-distal C face and a transverse ridge on the P 3 perpendicular to it, extending between the subequal cusps. An earlier adaptation to more efficient grinding may have resulted in reduced canine projection and the development of the lingual P 3 cusp, raising the ridge between it and the buccal cusp. This development acted to retain the anterior cutting function by shifting it to the top of the premolar.