Anterior Dental Cutting in the Laetolil Hominids and the Evolution of the Bicuspid P3
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چکیده
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, 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 P3 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
منابع مشابه
AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 73:41-63 (1987) Evolution of P3 Morphology in Australopithecus afarensis
The Australopithecus afarensis dental sample exhibits a wide range of variation, which is most notable in the morphology of the lower third premolar (P3). P3 morphology in the A. afarensis sample ranges from the primitive sectorial extreme in AL 128-23 to the derived, bicuspid (molarized) extreme in AL 333w-1. In this paper, the degree and patterning of variation of the 20 known A. afarensis P3...
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تاریخ انتشار 2005