Feather. Light micrograph of water droplets on a bird's feather. A feather consists of a central axis or shaft (light brown), with many slender barbs slanting off from it. The barbs bear interlocking barbules to form the flat vane of the feather. Feathers are necessary for flight, insulation, camouflage and attracting mates. They also waterproof the bird through their oily coating. Magnification: x7 at 6x7cm size. magnification: x12 at 4x5 inch size.