Rapid Evolution of Host Repertoire and Geographic Range in a Young and Diverse Genus of Montane Butterflies

作者：SHI-FANG MO, Yao‐Wei Zhu, Mariana P. Braga, David J. Lohman, Sören Nylin, Ashraf Moumou, Christopher W. Wheat, Niklas Wahlberg, Min Wang, Fangzhou Ma, Peng Zhang, Houshuai Wang · 发表于：Systematic Biology · 年份：2024 · DOI：10.1093/sysbio/syae061 · 被引用次数：3 · 研究领域：Lepidoptera: Biology and Taxonomy、Plant and animal studies、Species Distribution and Climate Change

Evolutionary changes in geographic distribution and larval host plants may promote the rapid diversification of montane insects, but this scenario has been rarely investigated. We studied the rapid radiation of the butterfly genus Colias, which has diversified in mountain ecosystems in Eurasia, Africa, and the Americas. Based on a data set of 150 nuclear protein-coding genetic loci and mitochondrial genomes, we constructed a time-calibrated phylogenetic tree of Colias species with broad taxon sampling. We then inferred their ancestral geographic ranges, historical diversification rates, and the evolution of host use. We found that the most recent common ancestor of Colias was likely geographically widespread and originated ~3.5 Ma. The group subsequently diversified in different regions across the world, often in tandem with geographic expansion events. No aspect of elevation was found to have a direct effect on diversification. The genus underwent a burst of diversification soon after the divergence of the Neotropical lineage, followed by an exponential decline in diversification rate toward the present. The ancestral host repertoire included the legume genera Astragalus and Trifolium but later expanded to include a wide range of Fabaceae genera and plants in more distantly related families, punctuated with periods of host range expansion and contraction. We suggest that the widespread distribution of the ancestor of all extant Colias lineages set the stage for diversificati...