Kaczvinsky Chloe, Hardy Nate B
Department of Entomology and Plant Pathology Auburn University Auburn AL USA.
Ecol Evol. 2020 Feb 26;10(8):3636-3646. doi: 10.1002/ece3.6116. eCollection 2020 Apr.
The Escape and Radiate Hypothesis posits that herbivorous insects and their host plants diversify through antagonistic coevolutionary adaptive radiation. For more than 50 years, it has inspired predictions about herbivorous insect macro-evolution, but only recently have the resources begun to fall into place for rigorous testing of those predictions. Here, with comparative phylogenetic analyses of nymphalid butterflies, we test two of these predictions: that major host switches tend to increase species diversification and that such increases will be proportional to the scope of ecological opportunity afforded by a particular novel host association. We find that by and large the effect of major host-use changes on butterfly diversity is the opposite of what was predicted; although it appears that the evolution of a few novel host associations can cause short-term bursts of speciation, in general, major changes in host use tend to be linked to significant long-term decreases in butterfly species richness.
逃逸与辐射假说认为，植食性昆虫及其寄主植物通过对抗性协同进化适应性辐射实现多样化。五十多年来，该假说激发了关于植食性昆虫宏观进化的预测，但直到最近，才开始有资源用于对这些预测进行严格检验。在此，我们通过蛱蝶科蝴蝶的比较系统发育分析，检验其中两个预测：主要寄主转换往往会增加物种多样化，且这种增加将与特定新寄主关联所提供的生态机会范围成正比。我们发现，总体而言，主要寄主利用变化对蝴蝶多样性的影响与预测相反；尽管少数新寄主关联的进化似乎会导致物种形成的短期爆发，但一般来说，寄主利用的重大变化往往与蝴蝶物种丰富度的显著长期下降有关。
