PROJECTS
Multispectral Coloration at the Burke Museum
Hummingbird sight has only been consistently studied in the last few years. Humans can see the visible spectrum of light, but that’snot all that exists. The sun produces ultraviolet light rays and there are also infrared light rays. We are aware that these ultravioletrays exist (have you ever had a sunburn?), but we as humans cannot detect them visually. Recent work (Stoddard et al., 2020) tells us that hummingbirds can see visible colors with three cones (like humans), but they also have a fourth cone that allows them to differentiate ultraviolet light as well!
A key part of our work at the Behavioral Ecophysics Lab is to investigate the role of coloration in sexual selection and behavior. One behavior that intrigues us, specifically, is a behavior we’ve seen in videos where a species of hummingbird (Pterophanes cyanopterus; Sapphirewing Hummingbirds) take a pause mid-flap, exposing the underside of their wing for an slightly longer duration than a typical flap. When they do this, a small patch of iridescent color is visible on the underside of the wing, and for a slightly longer period due to this pause. We want to know why they pause and what might be special about the colors on these patches– both for the bird who is flapping to show it off and also for the bird observing these color patches.
Taking these two factors into account we are asking the question: if we know coloration is used for communication, we know iridescence helps with this communication, and we know light interacts with color and iridescent patches– what does all this look like to another hummingbird?
