Faces Ancestry (image) Penn State Caption Facial features are affected by the response-based imputed variable for ancestry. First row shows the range of facial features three standard deviations to either side of the mean in profile and full face. Second row shows (left to right) the proportion of the total variation, and three primary facial shape change parameters:area ratio, curvature difference and normal displacement. Credit Shriver/Claes Usage Restrictions Non commercial use only Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.