Fig. 10. Saccades were employed, as with the wind stimuli
(Fig. 6) to orient flies
towards an attractive visual stimulus. A visual pattern expanding at 5 Hz in
the absence of a wind stimulus tended to elicit saccades that oriented flies
towards (blue bars) rather than away from the FOC (red bars), particularly at
the beginning of the trial (note that histograms are stacked). Flies also
exhibited a large number of saccades towards the end of trials with expansion
rates of 5 Hz, particularly when the FOC was at either the up- or the downwind
ends of the arena.