Data from: From cryptic to colourful: evolutionary decoupling of larval and adult colour in butterflies

Many animals undergo complete metamorphosis, where larval forms change abruptly in adulthood. Colour change during ontogeny is common, but there is little understanding of evolutionary patterns in these changes. Here we use data on larval and adult colour for 246 butterfly species (61% of all species in Australia) to test whether the evolution of colour is coupled between life stages. We show that adults are more variable in colour across species than caterpillars and that male adult colour has lower phylogenetic signal. These results suggest that sexual selection is driving colour diversity in male adult butterflies at a broad scale. Moreover, colour similarities between species at the larval stage do not predict colour similarities at the adult stage, indicating that colour evolution is decoupled between young and adult forms. Most species transition from cryptic coloration as caterpillars to conspicuous colouration as adults, but even species with conspicuous caterpillars change to different conspicuous colours as adults. The use of high-contrast coloration is correlated with body size in caterpillars but not adults. Taken together, our results suggest a change in the relative importance of different selective pressures at different life stages, resulting in the evolutionary decoupling of coloration through ontogeny.