Structural coloration

Colour in living creatures caused by interference effects

Structural coloration in animals, and a few plants, is the production of colour by microscopically structured surfaces fine enough to interfere with visible light instead of pigments, although some structural coloration occurs in combination with pigments. For example, peacock tail feathers are pigmented brown, but their microscopic structure makes them also reflect blue, turquoise, and green light, and they are often iridescent. Structural coloration was first described by English scientists Robert Hooke and Isaac Newton, and its principle—wave interference—explained by Thomas Young a century later.

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