Scale (zoology)

Small rigid plate that grows out of an animal's skin

In zoology, a scale (Ancient Greek: λεπίς, romanized: lepís; Latin: squāma) is a small rigid plate made out of keratin that grows out of vertebrate animals' skin to provide protection. In lepidopterans (butterflies and moths), scales are plates on the surface of the insect wing, made out of chitin instead of keratin, and provide coloration. Scales are quite common and have evolved multiple times through convergent evolution, with varying structure and function.

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