![]() ![]() Powder down, or pulviplumes, is a special type of down that occurs in a few groups of apparently unrelated birds. Powder down "Feather dust" left on a window after a birdstrike. : 470 Body down is a layer of small, fluffy feathers that lie underneath the outer contour feathers on a bird's body. Megapode hatchlings are the sole exception they are already covered with contour feathers when they hatch. Precocial nestlings are already covered with a layer of down when they hatch, while altricial nestlings develop their down layer within days or weeks of hatching. Natal down is the layer of down feathers that cover most birds at some point in their early development. There are three types of down: natal down, body down and powder down. It has a short or vestigial rachis (shaft), few barbs, and barbules that lack hooks. The down feather is considered to be the most "straightforward" of all feather types. ![]() The word down comes from the Old Norse word dúnn, which had the same meaning as its modern equivalent. The discovery of feathers trapped in ancient amber suggests that some species of non-avian dinosaur likely possessed down-like feathers.ĭescription and etymology Like many precocial hatchlings, domestic chickens are already covered with a coat of downy feathers when they hatch. Down is a fine thermal insulator and padding, used in goods such as jackets, bedding ( duvets and featherbeds), pillows and sleeping bags. Powder down is a specialized type of down found only in a few groups of birds. The down of birds is a layer of fine feathers found under the tougher exterior feathers. Soft, fine feather, sometimes under larger feathersĭown feathers lack the interlocking barbules of pennaceous feathers, making them very soft and fluffy. ![]()
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