For millennia birds have been prized, even hunted, for their beautiful plumage, but what makes their feathers so colorful? Read the fascinating work of physicist turned ornithologist Vinod Saranathan. At Phys.Org:
A new X-ray analysis of the structure of feathers from 230 bird species, led by Vinod Saranathan of Oxford University’s Department of Zoology, has revealed the nanostructures behind certain colours of feather, structures that could inspire new photonic devices.
A report of the research appears in the Journal of the Royal Society Interface.
“Pigments or dyes are the most common ways to make color in birds as in other organisms. Pigment molecules absorb certain portions of the white light spectrum and the portions that are not absorbed manifest as the colour we see,” Vinod tells me.
“For instance, melanosomes, granules filled with the pigment melanin, produce blacks, browns and reddish-browns in feathers, whereas other pigments such as carotenoids produce the majority of bright yellow, orange or reddish colors.”
He explains that parrots even have their own class of pigments (psittacofulvins) which give them their vivid yellow and red plumage.
“However, there are no known blue pigments found in vertebrates and the only known green pigment in birds is found in turacos, a group of birds endemic to sub-Saharan Africa,” Vinod says. More
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