| Popis: |
Wing shapes take flight Birds can dynamically alter the shape of their wings during flight, although how this is accomplished is poorly understood. Matloff et al. found that two mechanisms control the movement of the individual feathers. Whenever the skeleton moves, the feathers are redistributed passively through compliance of the elastic connective tissue at the feather base. To prevent the feathers from spreading too far apart, hook-shaped microstructures on adjacent feathers form a directional fastener that locks adjacent feathers. These features are found across a range of bird sizes; however, because the detachment of the hooks is noisy, they are notably absent in silent fliers, such as barn owls. Science , this issue p. 293 |
