Peppered moths in England were able to change the color of their wings based on their surroundings and the changes happening around them. While this is not a new fact, scientists have found that the genes responsible for this evolutionary adaption are also in the brilliantly colored tropical Heliconius butterflies in South America.
The moths were originally salt-and-pepper in color, camouflaging themselves against light-colored trees. As the Industrial Revolution hit, pollution started killing off the lichen and blackening the trees the peppered moths lived in. The moths then began changing their color to compensate, growing darker wings. Butterflies, on the other hand, use bright colors to warn predators as to their toxicity.
New research from the University of Cambridge and the University of Sheffield suggests that a gene called “cortex” is the driving force behind the colors of the butterflies. This segment of genetic code is known to play a part in cell division, which in turn makes it a major target for natural selection.
A similar paper from the University of Liverpool showed that the same gene was responsible for the change in wing colors of the peppered moth. These findings give insight as to how genetics makes evolution a process that can be predicted, although more studies have to be done for the cortex gene to be fully understood.
Chris Jigging of the University of Cambridge says,
What’s exciting is that it turns out to be the same gene in both cases. For the moths, the dark coloration developed because they were trying to hide, but the butterflies use bright colors to advertise their toxicity to predators. It raises the question that given the diversity in butterflies and moths, and the hundreds of genes involved in making a wing, why is it this one every time?
There are some 17,000 butterfly species and 160,000 moth species known to scientists. Their wings have minuscule scales, layered in alternating rows. Each butterfly or moth specie has a unique wing pattern. Until recently, scientists were unable to confirm how these patterns formed, despite over 100 years of research. Now, it appears they have a partial answer.
The study was published in the journal Nature.