Internal consistency predicts attractiveness in biological motion walkers

Why do some people appear attractive to us while others don't? Evolutionary psychology states that sexual attractiveness has evolved to assess the reproductive qualities of a potential mate. Past research in the field has identified a number of traits that can be linked directly to qualities such as immuno-competence, developmental stability, and fertility. The current study is motivated by the hypothesis that attractiveness is determined not just by individual, independent traits, but also by whether their pattern is internally consistent. Exploiting the domain of biological motion, we manipulated internal consistency between anthropometry and kinematics of a moving body. In two experiments, we varied internal consistency by using original point-light walkers (high internal consistency) and hybrid walkers, generated by combining anthropometric and kinematic data from different walkers (low internal consistency). As predicted, we found a significant link between internal consistency and sexual attractiveness, suggesting that internal consistency signals health and mate quality.