How Butterfly Wings Get Their Colors
A butterfly’s wings play a significant role when it comes to survival, and not just in terms of escape. Some colors and patterns displayed on each wing have evolved to mimic the appearance of species that don’t taste good to predators, which in turn makes those butterflies less appealing to creatures that might eat them, according to Professor David Lohman (City College of New York). But what determines those colors?
In collaboration with Professor George John (City College of New York), Lohman analyzed the chemical compositions of pigments found in the orange wings of two butterfly populations, one from Thailand and one from Indonesia. Both populations were female, belonged to the Elymnias hypermnestra species, and mimicked the colors of Danaus genus butterflies. Lohman and John published their results in the journal PLOS One.
There are over 50 species in the Elymnias genus, said Lohman, and almost every one mimics some distasteful butterfly. In the study, the researchers found that the shades of orange in each E. hypermnestra population, while similar, arose from different pigment mixtures. This could mean that while both groups evolved to mimic the same species, they did so in slightly different ways because of their environments.
“Things are not always what they seem,” Lohman said in an interview. “This may be the result of parallel evolution, in which evolution has acted on the same set of pre-existing genes to produce orange pigments that are chemically distinct but visually similar.”
Lohman is now part of a collaboration studying the genetics of color differences within E. hypermnestra, an endeavor the researchers hope will eventually shed light on color diversity in other species, too. “A long-term goal is to understand the genetic and developmental basis of such incredible wing pattern diversity and how it evolved within the genus,” Lohman said.
“How Did Butterflies Evolve? Their Color Chemistry Offers Clues” (GC News)
“Pigments In Butterfly Wings Lead Scientists To Colorful Conclusions” (CUNY News)