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 d...

许多动物会经历完全变态发育，即幼虫形态会在成虫阶段发生剧烈转变。个体发育过程中的体色变化现象较为普遍，但学界对这类变化的演化模式仍知之甚少。本研究基于覆盖澳大利亚全部蝴蝶物种61%的246个蝶类物种的幼虫与成虫体色数据，检验不同生命阶段的体色演化是否存在耦合关联。研究结果显示，相较于蝶幼虫，不同物种间成虫的体色变异程度更高，且雄性成虫体色的系统发育信号（phylogenetic signal）更低。上述结果表明，在宏观尺度上，性选择是推动雄性成虫蝶类体色多样性演化的主要动力。此外，物种间幼虫阶段的体色相似度无法预测其成虫阶段的体色相似度，这说明幼体与成体的体色演化彼此解耦。多数蝶类物种会从幼虫阶段的隐蔽色（cryptic coloration）转变为成虫阶段的醒目体色，但即便是幼虫体色醒目的物种，也会向……