How did feather coloration evolve over time? And which came first: brightly colored feathers or the color vision needed to see them?
A research team that dug through evolutionary trees and the fossil record found that color vision likely evolved 400 - 500 million years ago in both arthropods and backboned animals. But it wasn’t until about 100 million years ago that animals started using color to attract mates (and it started in fish). The animal world then saw an explosion of color, with the use of color-driven sexual selection independently evolving hundreds of times, including among birds.
Can we know what some of those colorful early birds looked like? A recently published study analyzed feathers of today’s birds for hints of what the fossil record might reveal about coloration in extinct species. The team ran spectral reflectance measurements on black, brown, gray and rufous feathers; the measurable differences between these colors may help future interpretation of fossilized feather coloration.
Other researchers are trying to understand the underlying mechanisms of feather coloration changes by studying the quickly evolving capuchino seedeaters. This group of South American birds is undergoing rapid evolutionary radiation, so the research team is analyzing how feather pigments and morphology interact and the differences between these quickly diverging, closely related species.