In many birds, some or all of the feathers lack the barbules or the hooks, and the plumage has a loose, hairlike appearance. …in turn, have branches, the barbules. The barbules on the distal side of each barb have hooks (hamuli) that engage the barbules of the next barb.

Fused to the rachis are a series of branches, or barbs; the barbs themselves are also branched and form the barbules. These barbules have minute hooks called barbicels for cross-attachment. Down feathers are fluffy because they lack barbicels, so the barbules float free of each other, allowing the down to trap air and provide excellent thermal ...

The meaning of BARBULE is a minute barb; especially : one of the processes that fringe the barbs of a feather.

Jul 2, 2010 · Each barb is a feather within a feather with a little shaft and little barbs of its own called barbules. When viewed as a whole the barbs are the vane. Barbules (too tiny to show above): Barbules are mini-barbs that grow from the central shaft of each barb.

Feb 10, 2024 · Feathers are made up of a central shaft called a rachis. Thin structures called barbs extend out from the rachis, forming the vane of the feather. The barbs have even smaller structures called barbules that have tiny hooks that allow the barbules to zip together, creating a unified vane surface.

Although microscopic evidence from fossil forms is scant, at some point the barbs evolved barbules, the tiny hooks that provide mechanical structure to the vanes and give them aerodynamic integrity. The first such feathers were simple…

The barbules evolved hooks that interlock to make flat vanes as in current contour feathers. 5. The feather structure evolved asymmetry with the aerodynamic properties of modern-day flight feathers.

Sep 14, 2024 · Birds have six different feather types that vary in shape, structure, and function. The most familiar is the contour feather. It consists of a central shaft and countless barbs that protrude from either side, forming vanes.

The bluebird's blue is called a "structural color," caused when light is scattered and reflected by tiny structures within each feather's myriad microscopic barbules. In the bluebird's case, the feathers reflect short-wavelength blue light, creating the lovely hue that inspired Thoreau to say bluebirds carry the sky on their backs.

Define barbules. barbules synonyms, barbules pronunciation, barbules translation, English dictionary definition of barbules. n. Zoology A small barb or pointed projection, especially one of the small projections fringing the edges of the barbs of feathers.