Hybrid zones act as natural laboratories where divergent genomes interact, providing powerful systems for examining the evolutionary processes underlying biological diversity. In this study, we characterized patterns of genomic and phenotypic variation resulting from hybridization between divergent intraspecific lineages of the Neotropical red‐eyed treefrog (Agalychnis callidryas). We found genetic evidence of a newly discovered contact zone and phenotypic novelty in leg colour—a trait suspected to play a role in mediating assortative mating in this species. Analysis of hybrid ancestry revealed an abundance of later‐generation F_n individuals, suggesting persistence of hybrids in the contact zone. Hybrids are predominantly of southern ancestry but are phenotypically more similar to northern populations. Genome‐wide association mapping revealed QTL with measurable effects on leg‐colour variation, but further work is required to dissect the architecture of this trait and establish causal links. Further, genomic cline analyses indicated substantial variation in patterns of introgression across the genome. Directional introgression of loci associated with different aspects of leg colour are inherited from each parental lineage, creating a distinct hybrid colour pattern. We show that hybridization can generate new phenotypes, revealing the evolutionary processes that potentially underlie patterns of phenotypic diversity in this iconic polytypic frog. Our study is consistent with a role of hybridization and sexual selection in lineage diversification, evolutionary processes that have been implicated in accelerating divergence in the most phenotypically diverse species.

中文翻译：

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遗传和表型上的标志性红眼树蛙的不同颜色形态之间的接触区的证据。

杂种区充当了不同基因组相互作用的自然实验室，为检查生物多样性基础的进化过程提供了强大的系统。在这项研究中，我们表征了由于新热带红眼树蛙（Agalychnis callidryas）的不同种内种系之间的杂交而导致的基因组和表型变异模式。我们发现了一种新发现的腿部颜色的接触区和表型新奇的遗传证据，该特征被怀疑在该物种的交配交配中起作用。对杂交血统的分析表明，有很多后代F _n个体，表明杂种在接触区的持久性。杂种主要是南方祖先，但在表型上更类似于北方种群。全基因组关联图谱揭示了QTL对腿色变异具有可测量的影响，但是需要进一步的工作来剖析该性状的结构并建立因果关系。此外，基因组突变分析表明整个基因组的渗入模式有很大变化。与腿部颜色的不同方面相关的基因座的方向性渗入从每个亲代谱系继承，从而创建了独特的混合颜色模式。我们表明杂交可以产生新的表型，揭示出可能是这一标志性多型青蛙表型多样性模式的基础的进化过程。