HomePLANTS & ANIMALSECOLOGYIn the colorful avian world, hummingbirds have the widest breadth of colorful...

In the colorful avian world, hummingbirds have the widest breadth of colorful plumage

Richard Prum, a Yale ornithologist, has spent years studying the molecules and nanostructures that give many bird species their vibrant plumage, but nothing prepared him for what he discovered in hummingbirds.
Prum and colleagues report in the journal Communications Biology on June 23 that the colour diversity of hummingbird plumage exceeds that of all other bird species combined.
“We knew hummingbirds were colourful, but we never imagined they’d outdo all the other birds,” said Prum, the William Robertson Coe Professor of Ornithology and Ecology and Evolutionary Biology.
Gabriela Venable, a former undergraduate student in Prum’s lab (now a graduate student at Duke University), collected data on the wavelengths of light reflected by feathers of 1,600 plumages from 114 species of hummingbirds for the study. The data was then compared to an existing dataset of colours found in the plumage of 111 other bird species, ranging from penguins to parrots.
The Yale team was able to describe the diversity of avian plumage colours as seen by the birds themselves, including hues that are not visible to humans, using their knowledge of avian visual physiology.
Colour cones in birds are sensitive to four colors: red, green, blue, and ultraviolet/violet. As a result, birds can see all of the colours that humans can see. They can, however, see a variety of other colours that humans cannot, including ultraviolet and ultraviolet mixtures with other hues, such as ultraviolet-yellow and ultraviolet-green. These colours are as dissimilar to yellow and green as purple is to blue and red. Hummingbirds contribute to avian colour diversity by producing more of these combination colours than other birds.
According to the team’s new findings, the diversity of bird-visible colours in hummingbird plumages exceeds the known diversity of colours found in all other bird species’ plumages combined, increasing the total number of known bird-visible plumage colours by 56%. Colors revealed in the plumage of hummingbirds include saturated blues, blue-greens, and deep purples, which are most variable on the animals’ crowns and throats, which they display prominently during mating displays and social interactions.
The sheer variety of colours in hummingbird plumage is due to nanostructures in their feather barbules, the smallest filaments that project from their feather barbs.
“It’s pretty amazing to watch a single hummingbird,” Prum said. “However, the combination of hummingbirds’ versatile optical structures and complex sexual displays makes them the most colourful bird family of all.”

LEAVE A REPLY

Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Latest Science News Articles - PhysicsAlert.com

explore more