Two Sides to a Wing: A Gene that Makes Butterfly Upper and Bottom Wing Patterns Different

Abstract

Butterflies, with their colorful and intricate wing patterns, have inspired artists and poets for many centuries. The variations in hues and patterns on their wings are not just for show but perform crucial communication functions. The patterns on the wings can help protect butterflies from predators through camouflage, or warn predators that the butterfly’s body is toxic, or help attract potential mates. A major feature of these wing canvases is that they have two sides and they can contain different messages on each side. In general, butterflies use the upper surfaces of their wings to seduce the opposite sex, whereas they use the lower surfaces to hide from view or to communicate to their predators that eating them would be toxic. We have identified a gene that is responsible for creating the upper surface “seductive message” patterns. This gene, when mutated, transforms both surfaces of the butterfly wing into the lower surface wing pattern “anti-predation” message. This article discusses how we identified this butterfly wing gene that turns a two-sided canvas into a repeated one-sided canvas.