Cover image

Cover: During courtship, fruit flies Drosophila melanogaster produce songs by moving one of their wings. The flies perceive the resulting acoustic waves (oscillographic waveform depicted by glyphs) with tiny antennal hearing organs. Operating over short distances, this acoustic communication makes use of the properties of sound propagation in the acoustic near-field. In effect, the motion of the air particles in the sound field generates viscous forces that make the antennae oscillate. Using microscanning laser Doppler vibrometry and pressure-gradient microphones, an examination of antennal auditory mechanics revealed the rotational pattern of antennal motion and its non-linear mechanical response. Composite image by Bob Porter, Martin Göpfert and Daniel Robert, School of Biological Sciences, University of Bristol (see Göpfert and Robert, pp. 1199-1208).