Fig. 4. The fly’s visual environment influences the spatial structure of its flight trajectory. (A) Sample trajectories taken within uniform (left) and textured (right) backgrounds showing the effects of changing the fly’s visual environment. The inter-saccade segments are longer for flight within the uniform background, causing saccades to occur farther from the center of the arena. (B) Histogram of the fly’s position within the arena for uniform and textured backgrounds pooled over multiple flies. The transit probability peaks in the center of the arena with a textured background and is more evenly distributed with the uniform background. (C) Histograms showing the distribution of saccade locations. Within a textured background, flies tend to saccade in the middle of the arena. Position bins are 50 mmx50 mm. Uniform background data represent 58 trajectories totaling 916 s containing 1080 saccades; textured background data represent 36 trajectories totaling 1020 s containing 1579 saccades.
