Meeting Abstract
Flying insect process and integrate a variety of visual and other sensory cues to find and approach targets. Even with coarse vision and tiny brains, they can find flowers, prey items, trees, or other resources with startling skill. But it is often unclear how they use the dynamic images in their visual field to navigate to their intended destination. We set out to determine how fruit flies balance the wide-field optic flow with the motion of the smaller target they wish to approach when they chart a course towards it. To do this we put tethered flies in a closed-loop, virtual environment with a vertical target to approach, and wide-field features to help stabilize flight. Fruit flies have long been noted for their interest in vertical features, in both tethered and free flight, and their strong responses to wide-field visual stimuli. Although the tethered arena fails to capture all the aspects of natural flight, it is sufficiently convincing that our flies robustly steered towards the vertical bar. We characterized the probability that flies could find and arrive at the target, and then the shape of the path they used to approach it. We found that both the density and location of wide-field cues affected the likely success of getting to the bar, and the path of approach. These effects are consistent with the hypothesis that flies adjust their flight paths towards small targets to increase the information the acquire from wide-field optic flow.
