I think this is far too simplistic. Chickens and ducks have both pigments and iridescence in their feathers. It isn’t an either-or phenomenon; both are present in the same animal and even on the same feather.Alfred Cann said:Summary:: Colors of bird feathers and butterfly wings
They are mostly attributed to interference in microscopic structures, not dyes, yet do not display the typical change of color with viewing angle of interference colors. Why?
This appears to be the core of the question.Alfred Cann said:[The colours] do not display the typical change of color with viewing angle of interference colors. Why?
Alfred Cann said:yet do not display the typical change of color with viewing angle of interference colors. Why?
Colors through interference don't have to be angle-insensitive. See post #5.Alfred Cann said:1. Most bird and butterfly colors appear quite angle-insensitive, not even Fabry-Perot. Is the literature wrong that I have read, that attributes these colors to interference?
Interference colors are colors that are produced when light waves interact with the microscopic structures on the surface of a material, causing some wavelengths of light to be amplified and others to be cancelled out. These colors are often iridescent and change depending on the angle of observation.
Bird feathers and butterfly wings have specialized structures called photonic crystals that are made up of layers of proteins and air. When light hits these structures, it is reflected and refracted in a way that produces interference colors.
The purpose of interference colors in birds and butterflies is primarily for communication and camouflage. These colors can help attract mates, intimidate rivals, and blend into their surroundings.
No, not all animals can see interference colors. Some animals, such as birds and butterflies, have specialized vision that allows them to see these colors, while others, like humans, may not be able to see them at all or only see them as a dull, gray color.
Scientists use a variety of techniques such as microscopy, spectroscopy, and computer modeling to study the structures and properties of photonic crystals in bird feathers and butterfly wings. They also observe these animals in their natural habitats and conduct experiments to understand the function of interference colors.