Figure 1.

Figure 1.

Behavior at scale. A, top panel, Five consecutive frames from an individual well of a 96-well plate as a 6 dpf zebrafish larva performs a swim bout. Blue highlights pixels that change intensity between frames (Δ pixels). Lower panel. A Δ pixels time series from the larva above. Highlighted are the features that describe each active and inactive bout. B, Mean bout frequency (Hz) recorded from individual larvae at 5 and 6 dpf during the day (light blue) and the night (dark blue). Each dot is 1 of 124 wild-type larvae. The orange crosses mark the population means. C, The probability of observing different lengths of inactivity during the day (light blue) or the night (dark blue) at 5 and 6 dpf. Each larva’s data were fit by a pdf. Shown is a mean pdf (bold line) and SD (shaded surround) with a log scale on the x-axis cropped to 10 s. Inset, The total probability of inactive bout lengths longer than 10 s, per animal. D, The mean activity of 124 wild-type larvae from 4 to 7 dpf, on a 14/10 h light/dark cycle. Data for each larva was summed into seconds and then smoothed with a 15-min running average. Shown is a summed and smoothed mean Δ pixels trace (bold line) and SEM (shaded surround). E, Average activity across one day (white background) and night (dark background) for larvae dosed with either DMSO (control) or a range of melatonin doses immediately before tracking at 6 dpf. Data were summed and smoothed as in D. The number of animals per condition is denoted as n. Extended Data Figures 1-1, 1-2, 1-3 support Figure 1.