Among the different species of birds, hummingbirds are among the most iconic and distinct in the skies. These unique creatures hover unlike most birds, they feed on sugary nectar, and they have incredible metabolisms. They also have the most wide-ranging colors in their plumage of all other birds.
A recent study from Yale University published in Communications Biology showed that hummingbirds, in fact, exceed the color diversity of all other bird species combined.
The work began with Richard Prum, a professor of ornithology of ecology and evolutionary biology at Yale University, who has been studying the molecules and nanostructures that give many bird species their rich colorful plumage for years.
“We knew that hummingbirds were colorful, but we never imagined that they would rival all the rest of the birds combined,” says Prum.
The study examined data on the wavelengths of light reflected by the feathers of 1,600 samples of plumages from 114 species of hummingbirds. These findings were compared with the data collected from 111 other wide-ranging bird species.
Some of the myriad colors are visible to bird eyes but not to humans. Birds can see all of the colors humans can and many that we can’t, such as ultraviolet. They can also see ultraviolet mixed with other hues, like ultraviolet-yellow and blue. Combining ultraviolet is one of the ways that hummingbirds add to their color profile that makes them distinct from other birds.
According to the study, hummingbirds’ diversity of bird-visible colors in their plumage is higher than that of all other bird species combined. In fact, they increase the total of known bird-visible plumage colors by 56%. The reason for this is a difference in the nanostructure of their feather barbules, the smallest filaments that project from their feather barbs.
“Watching a single hummingbird is pretty extraordinary,” Prum says. “But the combination of versatile optical structures and complex sexual displays make hummingbirds the most colorful bird family of all.”
Source Study: Communications Biology — Hummingbird plumage color diversity exceeds the known gamut of all other birds | Communications Biology (nature.com)