plumage
collective feathered covering of a bird. It provides protection, insulation, and adornment and also helps streamline and soften body contours, reducing friction in air and water. Plumage of the newborn chick is downy, called neossoptile; that which follows is termed teleoptile. Juvenal plumage, frequently distinct from that of the adult bird, is often drab, streaked, or spotted and thus camouflages the young
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