Relationship between Chromatic Colour Change and Conspicuousness of Dominant Colour Signals
(A) Top flank (r2 = 0.30, p = 0.008); (B) mid flank (r2 = 0.54, p = 0.0001); (C) bottom flank (r2 = 0.36, p = 0.003). Chromatic contrast against the vegetation background (y-axis) is denoted as CC to background. Plots are regressions through the origin of Felsenstein's independent contrasts (FIC, positivized on the x-axis). For each variable, there are N – 1 contrasts, and one outlier was removed from each plot, resulting in 19 points (r2 and p-values are for regressions with the outlier removed). The outlier in each case is the contrast between B. pumilum from Stellenbosch and B. pumilum from Vogelgat. These lineages are very closely related but differ greatly in both habitat (vegetation) and display coloration, resulting in large contrasts. Lines indicate regression slopes.