Greenfield L O
Department of Anthropology, Temple University Philadelphia.
Z Morphol Anthropol. 1990;78(2):155-68.
Most theories of human canine evolution are unicausal and only purport to explain size and related shape changes in human canines. The present work tests whether one of the morphological changes, dulling of the distal edge of the maxillary canine, can be entirely explained as a byproduct of changes in the overall shape of the canine. The data show that the distal edge of maxillary canines of A. afarensis became far duller than would be predicted from changes in crown shape. The greater than expected dullness of the distal edge can be explained by evolutionary changes in the genetic field for cheek tooth morphology. This suggests that human canine evolution is complex and cannot be accounted for by unicausal theories.
大多数人类犬齿进化理论都是单因的，仅旨在解释人类犬齿的大小及相关形状变化。本研究检验了一种形态变化，即上颌犬齿远中边缘变钝，是否能完全解释为犬齿整体形状变化的副产品。数据表明，阿法南方古猿上颌犬齿的远中边缘变得比根据牙冠形状变化所预测的要钝得多。远中边缘超乎预期的钝度可通过颊齿形态遗传领域的进化变化来解释。这表明人类犬齿进化是复杂的，不能用单因理论来解释。
