Department of Biology, Utah State University, Logan, UT, 84322, USA.
Ecology Center, Utah State University, Logan, UT, 84322, USA.
Nat Commun. 2020 May 1;11(1):2179. doi: 10.1038/s41467-020-15641-x.
Genomic outcomes of hybridization depend on selection and recombination in hybrids. Whether these processes have similar effects on hybrid genome composition in contemporary hybrid zones versus ancient hybrid lineages is unknown. Here we show that patterns of introgression in a contemporary hybrid zone in Lycaeides butterflies predict patterns of ancestry in geographically adjacent, older hybrid populations. We find a particularly striking lack of ancestry from one of the hybridizing taxa, Lycaeides melissa, on the Z chromosome in both the old and contemporary hybrids. The same pattern of reduced L. melissa ancestry on the Z chromosome is seen in two other ancient hybrid lineages. More generally, we find that patterns of ancestry in old or ancient hybrids are remarkably predictable from contemporary hybrids, which suggests selection and recombination affect hybrid genomes in a similar way across disparate time scales and during distinct stages of speciation and species breakdown.
杂交的基因组结果取决于杂种中的选择和重组。这些过程在现代杂交区和古老的杂交谱系中对杂种基因组组成的影响是否相似尚不清楚。在这里，我们表明，在 Lycaeides 蝴蝶的一个现代杂交区中，基因渐渗的模式可以预测地理上相邻的、更古老的杂交群体的祖先模式。我们发现，在旧的和现代的杂交种中，来自杂交种之一 Lycaeides melissa 的 Z 染色体的祖先特别缺乏。在另外两个古老的杂交谱系中也观察到了 Z 染色体上 L. melissa 祖先减少的相同模式。更一般地说，我们发现，古老或古老的杂交种的祖先模式可以从现代杂交种中非常准确地预测，这表明选择和重组以相似的方式影响不同时间尺度和不同物种形成和物种崩溃阶段的杂种基因组。
