Developmental biologists at Tufts University have identified a "self-correcting" mechanism by which developing organisms recognize and repair head and facial abnormalities. The research, reported in the May 2012 issue of the journal Developmental Dynamics, used a tadpole model to show that developing organisms are not genetically "hard-wired" with a set of pre-determined cell movements that result in normal facial features. Instead, the study shows that cell groups are able to measure their shape and position relative to other organs and perform the movements and remodeling needed to compensate for significant patterning abnormalities. Here three abnormal facial structures on the right side of a tadpole self-repair over time. On days 9 to 23, the branchial arch, or gill, (arrowhead) is almost flat rather than displaying the expected curvature, the right side of the jaw (arrow) is deformed, and the right eye is out of position and displays a "chocolate kiss" shape. By day 131-170, the branchial arch has become curved, the jaw displays the expected "U" shape and the right eye has moved up to align with the left eye and has a more rounded shape.