system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Is the stuff that makes animals feathers and fur a multitude of colors the same as the stuff we use to dye materials?

I know that chlorophyll makes plants produce their green color, but what makes a peacocks feathers into a rainbow? Is it the same thing we use to color crayons?
gpt
The "rainbow" effect like peacock feathers and beetle shells isn't a dye, it's an optical effect called "diffraction" caused by very small physical features of the surface. It's roughly similar to the physics of rainbows or the colours you see with gasoline on water. You can't extract that and put it in something else, like a crayon, because it's physical, not chemical.