This time lapse video was created by Aaron Pomerantz, a Berkeley graduate student, who performed a ‘window surgery’ to get a closer look into the metamorphosis of a caterpillar. This ‘window’ was created by making a small incision into the caterpillar and pulling out cells that would normally form one of the butterfly’s forewings. With this clear window into the pupae, Pomerantz was able to photograph the metamorphosis. He took an image every twenty minutes and captured almost a thousand images during the 8-day butterfly pupation.
His research revealed the structural color formation of the butterfly’s wings. According to the National Geographic, structural color formation “is created by the interaction of light with tiny nanostructures in the wing.” Some colors in birds and butterflies, such as yellow or black, are created by pigments, but in butterflies, the color blue is a structural color that appears as their wings grow thicker.
Although these ‘window surgeries’ inhibit the growth of the butterfly’s forewing, they are still able to fly with three wings. According to Pomerantz, the three-winged butterflies from these experiments are not released into the wild. Instead, the butterflies are put into a Berkeley greenhouse.