FIGURE 4.

Measurements of Xenopus craniofacial features. (A) Representative frontal view image of stage 42 X. laevis tadpole. Measurements of facial features include facial height (blue line), facial width (orange line), facial area (red dotted line), facial angle (green line), and mouth roundness (yellow dotted line). Facial height is measured from the top of the middle of the eyes to the top of the cement gland. Facial width is measured from the middle of one eye to the middle of the opposite eye. Facial area is measured as the area around the top of the eyes to the top of the cement gland. Facial angle is measured as the angle between the middle of the eyes and the top of the cement gland. Mouth roundness is measured as the area around the periphery of the mouth. (B) Representative lateral view image of stage 42 X. laevis tadpole. Measurements of facial features include eye area (red dotted line) and snout length (orange line). Eye area is measured as the area around the periphery of the eye. Snout length is measured from the most anterior part of the face to the bottom of the eye. All measurements can be performed using ImageJ. cg, cement gland. Scale bar: 100 μm.