Figure 5.

Drosophila larvae phototaxis under natural lighting conditions. (A) Schematic of the outdoor behavioral assay. Azimuth is the horizontal angle from north to the position of the sun. Azimuth defines in which direction the sun is. North has azimuth 0° and east has azimuth 90°. Altitude is the vertical angle from the horizon (0°) to center of the sun and defines the elevation of the sun. Zenith has altitude 90°. (B) Preference indices of WT larvae under cloudy conditions in the morning and evening respectivly. (C,D) Preference indices of WT, Rh6 single mutant larvae, Rh5 single mutant larvae, Rh5 and Rh6 double mutant larvae and Gr28b mutant larvae stimulated with either direct sun light (C) or with diffuse sun light under cloudy conditions (D). Data show the mean and error bars indicate ± SEM. Rejection of the null hypothesis that the mean of the data set is 0: *p < 0.05, **p < 0.01, ***p < 0.001, One sample t test. Or rejection of the null hypothesis that the mean of two data set is the same: *p < 0.05, **p < 0.01, ***p < 0.001, unpaired t test.