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Physics

Optical Interference

Quick fact

Optical interference is responsible for the iridescent colors seen in butterfly wings and peacock feathers, not from pigments but from microscopic structures that cause light waves to interfere constructively or destructively for different wavelengths.

Why this is interesting

Have you ever noticed the rainbow colors in a soap bubble or an oil slick? These colors are not from pigments but from a fascinating phenomenon where light waves combine, amplify, or cancel each other out.