Field evidence for colour mimicry overshadowing morphological mimicry

1. Imperfect mimicry may be maintained when the various components of an aposematic signal have different salience for predators. Experimental laboratory studies provide robust evidence for this phenomenon. Yet, evidence from natural settings remains scarce. 2. We studied how natural bird predators assess multiple features in a multicomponent aposematic signal in the Neotropical “clear wing complex” mimicry ring, dominated by glasswing butterflies. 3. We evaluated two components of the aposematic signal, wing colouration and wing morphology, in a predation experiment based on artificial replicas of glasswing butterflies (model) and Polythoridae damselflies (mimics) in their natural habitat. We also studied the extent of the colour aposematic signal in the local insect community. Finally, we inspected the nanostructures responsible for this convergent colour signal, expected to highly differ between these phylogenetically distinct species. 4. Our results provide direct eviden...1. 当警戒信号（aposematic signal）的不同组分对捕食者具有不同显著性时，不完善拟态（imperfect mimicry）或可得以维持。实验室实验已为该现象提供了可靠证据，但自然环境中的相关证据仍较为稀缺。 2. 我们以新热带区以透翅蝶（glasswing butterfly）为优势类群的“透翅翅复合体”拟态环为研究对象，探究野生鸟类捕食者如何对多组分警戒信号中的多项特征进行评估。 3. 我们在其自然栖息地开展捕食实验，以透翅蝶（模型类群）与扁蟌科（Polythoridae）豆娘（拟态类群）的人工复制品为实验材料，评估了警戒信号的两个组分——翅部体色与翅部形态。此外，我们还调查了当地昆虫群落中警戒体色信号的分布范围；最后，我们对介导这类趋同体色信号的纳米结构进行了检测——这类结构在系统发育分化显著的物种间理应存在显著差异。 4. 我们的研究结果提供了直接的实验证据……