Click on image to view larger version.

Fig. 2. Skin darkness of socially dominant and subordinate Arctic charr allowed to
interact in pairs on a white (N=7) or black (N=7)
background. Skin darkness was measured on a linear grey scale, where 0 is
white and 255 is black, 24 h before (white bars) and after 5 days (black bars)
of social interaction. Controls are fish that were visually isolated on the
white (N=8) or black (N=8) background. Values are means +
S.E.M. Means with no common superscript letters are significantly different
(P<0.05; Sheffé post hoc test).