Fig. 2. Apparatus and analysis. (A) Schematic drawing showing the arrangement of
the loudspeaker, the animal, the pressure-gradient microphone and the laser
Doppler vibrometer (LDV). The vibration velocity 
vib was
assessed via the LDV, the particle velocity air
via the microphone. (B) Detail from A depicting the animal's
orientation during the measurements (in contrast to the picture shown, the
animal's wings and legs were removed for experiments). (C) Comparison between
the measured velocity response of an arista (red trace) and the fitted
function of a simple harmonic oscillator (blue trace). Magnitude (left panel)
and phase (right panel) responses are shown. The fitted function is described
by f0=394Hz, Q=1.24 and
vib/air at f0=1.13, where
f0 is the resonance frequency and Q is the quality
factor.
