Figure 2

First two axes of principal component analyses for non-normalized (a) and normalized (b) photospectral compositions. The plots show the positions in the colour space of the tadpole dorsal pigmentation (small points) relative to the position of the background (large points of the same colour) that tadpoles were reared on. Fill colours represent the background colours that tadpoles were reared on. For example, large red point represents the mean colour measurement of the red containers, and the five small red points represent the colour measurements of the tadpoles reared in this red container. The boxplots (c,d) show Euclidean distances in colour space between the tadpole pigmentation and their corresponding background (distance between smaller and larger points in the PCA). Larger distances therefore represent greater mismatch between the tadpole dorsal colour and their corresponding background.