Figure 1.

An ultradian feeding rhythm is regulated by cryptochrome and light. Bars on top of each panel indicate light:dark (LD) (white/black) or dark:dark (DD) (gray/black) cycles, while zeitgeber time or circadian time in hours is shown at the bottom. (A) Locomotor activity of wild-type flies and tim⁰¹ arrhythmic mutants under 12:12 LD and DD conditions (n = 32 for each genotype). The number of beam breaks was summed into 30-minute bins and is presented as first quartile (light gray), median (black), and third quartile (dark gray) values. (B) Feeding behavior measured as radioactive counts consumed during 2-hour intervals for wild-type flies and tim⁰¹ mutants under 12:12 LD and DD conditions (n > 1700 for each genotype). Boxes depict the interquartile range for each time point, with the median indicated by a horizontal bar and the lighting condition represented by shading. (C) Feeding behavior of cry⁰¹ mutants under 12:12 LD conditions (n > 540). All data are compiled from 4 biologically independent experiments (*p < 0.01, Student’s t test).