Data from: Parapatric genetic introgression and phenotypic assimilation: testing conditions for introgression between Hercules beetles (Dynastes, Dynastidae)

The prevalence and consequences of genetic introgression between species have been intensively debated. I used Hercules beetles as examples to test for conditions that may be associated with the occurrence of introgression. RADseq data were used to reconstruct the species tree and history of introgression between Hercules beetles. Image data from museum specimens were used to investigate the phenotypic similarity of two adaptive traits between species from two distinct climatic realms (Nearctic versus Neotropical). Genetic introgression was identified between Hercules beetles living in geographic proximity (parapatric). Phylogenetic relatedness and phenotypic similarity did not predict nor preclude genetic introgression between species. Phenotypic assimilation in body coloration was evident between distantly related Hercules beetles co-distributed in Central America, where directional introgression was also statistically supported from the putative donor to receiver lineages. The number of introgressed loci was significantly higher between species with than without phenotypic similarity. I discuss the implications of recent studies on adaptive genetic introgression by providing supporting evidence from the Hercules beetle system.物种间遗传渐渗（genetic introgression）的普遍性及其演化后果长期以来备受学界热议。本研究以长戟犀金龟（Hercules beetles）为研究对象，旨在检验与遗传渐渗发生相关的潜在条件。本研究利用限制性位点关联DNA测序（RADseq）数据，重构了长戟犀金龟的物种树及其种间遗传渐渗历史。此外，本研究借助博物馆馆藏标本的图像数据，对两个截然不同的气候域（新北区（Nearctic）与新热带区（Neotropical））内的犀金龟物种的两种适应性性状（adaptive traits）的表型相似性（phenotypic similarity）展开了分析。研究发现，地理毗邻的邻域分布（parapatric）长戟犀金龟类群之间存在遗传渐渗现象。系统发育亲缘关系（phylogenetic relatedness）与表型相似性既无法预测物种间的遗传渐渗发生，也不能阻碍这一过程。在同分布于中美洲的亲缘关系较远的长戟犀金龟之间，体色（body coloration）的表型同化（phenotypic assimilation）现象十分显著；同时，统计学分析支持存在从推定供体谱系向受体谱系的定向遗传渐渗（directional introgression）。具有表型相似性的物种类群对之间，渐渗位点（introgressed loci）的数量显著高于无表型相似性的类群对。本研究通过长戟犀金龟研究体系提供的佐证证据，探讨了近期适应性遗传渐渗相关研究的理论启示。