Fig. 5From: The consistent difference in red fluorescence in fishes across a 15 m depth gradient is triggered by ambient brightness, not by ambient spectrumDaily change in eye fluorescence brightness measured in the last week of the brightness experiment. Iris fluorescence measured as total photon radiance (photons s−1 sr−1 m−2) in Tripterygion delaisi after the final reversal of the light conditions (n = 19). Experimental day 0 is identical to the measurement taken during week 6 in Fig. 5. Lights were changed in the morning of the first experimental day. Fish previously held under dark light conditions (group 1) received the bright light treatment for the following 7 days whereas fish deriving from bright light conditions (group 2) changed to the dark light treatmentBack to article page