Fig 2.

Facial surface warps modeling the shape variation associated with PC4 (along the horizontal axis) and PC5 (along the vertical axis). The centrally located face represents the average or consensus facial surface for the sample. Movement along the principal axes of shape variation in either direction away from the consensus face is accompanied by the 3D displacement of landmarks and modeled as a deformation of the consensus 3D surface. This deformation reflects the major modes of shape variation associated with PC4 and PC5, respectively.