Individual variation in facial expressivity: An evolutionary hypothesis

摘要

Individuals differ in facial anatomy (size, structure and number of facial muscles) and how successfully they use facial expression as social tools. Here, we propose a unifying evolutionary hypothesis to explain these phenomena. We suggest that differences in facial expressivity reflect how individuals situate themselves within a social network. In an interdisciplinary study, we will combine psychological, anatomical and cross-species methods to document individual differences in facial expressivity and measure how this is related to social function.