Fig. 2 Thin plate spline deformations of shape of lower lip representing positive and negative extremes observed among samples. A) Positive scores on RW1 represent June sucker-like shapes. B) Negative scores on RW1 represent Utah sucker-like shapes. C) Negative scores on RW2 represent June sucker-like shapes. D) Positive scores on RW2 represent Utah sucker-like shapes.