Data from: Complex dynamics underlie the evolution of imperfect wing pattern convergence in butterflies

Adaptive radiation is characterized by rapid diversification that is strongly associated with ecological specialization. However, understanding the evolutionary mechanisms fueling adaptive diversification requires a detailed knowledge of how natural selection acts at multiple life-history stages. Butterflies within the genus Adelpha represent one of the largest and most diverse butterfly lineages in the Neotropics. Although Adelpha species feed on an extraordinary diversity of larval hosts, convergent evolution is widespread in this group suggesting that selection for mimicry may contribute to adaptive divergence among species. To investigate this hypothesis, we conducted predation studies in Costa Rica using artificial butterfly facsimiles. Specifically, we predicted that non-toxic, palatable Adelpha species that do not feed on host plants in the family Rubiaceae would benefit from sharing a locally convergent wing pattern with the presumably toxic Rubiaceae-feeding species via reduced predation. Contrary to expectations, we found that the presumed mimic was attacked significantly more than its locally convergent model, at a frequency paralleling attack rates on both novel and palatable prey. Although these data reveal the first evidence for protection from avian predators by the supposed toxic, Rubiaceae-feeding Adelpha species, we conclude that imprecise mimetic patterns have high costs for Batesian mimics in the tropics.

适应辐射（Adaptive radiation）的典型特征为快速物种分化，且该过程与生态特化紧密关联。然而，要阐明驱动适应性分化的进化机制，需详尽掌握自然选择如何作用于多个生活史阶段。Adelpha属蝴蝶是新热带区规模最大、多样性最丰富的蝴蝶支系之一。尽管该属物种的幼虫寄主植物类群极其多样，但类群内趋同进化（convergent evolution）现象极为普遍，这提示拟态选择或许推动了物种间的适应性分化。为验证这一假说，我们在哥斯达黎加开展了基于人工蝴蝶模型的捕食实验。我们提出具体预测：不以茜草科（Rubiaceae）植物为寄主的无毒、适口的Adelpha物种，若与假定具有毒性、以茜草科植物为食的类群共享当地趋同的翅纹，可通过降低被捕食概率获得收益。但实验结果与预期相悖：我们发现，被视作拟态者的类群被捕食率显著高于其当地趋同的模型类群，其被捕食频率与全新、适口的猎物相当。尽管本研究首次证实了假定具有毒性、以茜草科植物为食的Adelpha物种可获得鸟类捕食者的保护，但我们得出结论：不精确的拟态模式会给热带地区的贝茨拟态者（Batesian mimic）带来高昂代价。