Do you know anything about the Jamaican click beetle?
It's a bioluminescent insect and it's belly glows orange.
The males of this species fly around at night searching for females. The light they emit on their bellies makes them visible to females who are stationary in trees and bushes. The gals, if they're interested, respond by emitting light from their backs.
What's more interesting is the range of color emitted by the insects. The Jamaican click beetle is unique among bioluminescent creatures for emitting several different colors. The light the species emits varies from green to yellow-green to orange, depending on an individual insect's genes.
What's more is that the appearance of orange is a relatively new phenomenon, but one that is quickly spreading as a result of sexual selection. That is, female Jamaican click beetles prefer males who emit orange light versus a green or yellow hue.
Perhaps there some evolutionary advantage to orange, such as better protection from predators. If so, scientists don't know what that advantage is just yet.
What they can verify is that this female preference for orange is evolving in the species before our very eyes. The orange light first appeared in an isolated population of the beetles in eastern Jamaica. This is where the concentration of orange lights is highest, but the color is spreading across the island as we speak.