It turn out, wing of bird was very well designed, er, evolved. According to New Scientist’s report and Journal of Fluid Mechanic, the vibration of some convert feathers on bird’s wing reduce drag on the wing significantly by sticking up at right angles to the surface. This finding, allows researcher to create synthetic feathers as rigid keratin bristles 4 to 6 centimetres long and 0.5 millimetres in diameter which can reduce drag on cylinder by 15%. Quote fro NS,
“With the feathers, the low-pressure slipstream does not form, and the vortices affecting the cylinder are weaker.”
(Link)NS, Fake feathers could take the drag out of flights.