Morphological divergence between walking-stick taxon pairs.

We consider here ten traits that were examined in [71], as well as principle components (PC) axes generated from all these ten traits or from the colour variables only. Divergence in trait means between hosts was often statistically significant for all three taxon pairs (testing using F-ratios in ANOVA analyses), but the magnitude of divergence tended to be greater for the species pair than the ecotype pairs (particularly for colour traits, which are known to be under host-specific selection). Mean trait values are shown for Ceanothus (C) and Adenostoma (A), along with the difference between means (D = mean on Ceanothus minus mean on Adenostoma). Also shown is the percent difference between means (% Δ), calculated as 1–(smaller value/larger value). Thus, larger values of % Δ represent larger differences between taxon pairs (due to negative means, this calculation was not conducted for PC axes). This calculation is in bold to emphasize standardized differences between taxon pairs. Traits are as follows: 1 = body hue, 2 = body saturation, 3 = body brightness, 4 = stripe hue, 5 = stripe saturation, 6 = stripe brightness, 7 = head width, 8 = femur length, 9 = thorax width, 10 = body length, 11 = PC1 using all ten traits, 12 = PC2 using all ten traits, 13 = PC1 using only colour variables, 14 = PC2 using only colour variables.