Studying how isolation can impact population divergence and adaptation in co-distributed species can bring us closer to understanding how landscapes affect biodiversity. The Sargo, Anisotremus davidsonii (Haemulidae), and the Longjaw mudsucker, Gillichthys mirabilis (Gobiidae), offer a notable framework to study such mechanisms as their Pacific populations cross phylogeographic breaks at Point Conception, California, United States, and Punta Eugenia, Mexico, and are separated to those in the Sea of Cortez by the Baja California peninsula. Here, thousands of loci are genotyped from 48 Sargos and 73 mudsuckers using RADseq to characterize overall genomic divergence, and search for common patterns of putatively neutral and non-neutral structure based on outlier loci among populations with hypothesized different levels of isolation. We further search for parallels between population divergence and the total proportion of outliers, outlier FST distribution, and the proportion of outliers matching coding regions in GenBank. Statistically significant differentiation is seen across Point Conception in mudsucker (FST = 0.15), Punta Eugenia in Sargo (FST = 0.02), and on either side of the Baja California peninsula in both species (FST = 0.11 and 0.23, in Sargo and mudsucker, respectively). Each species shows structure using neutral and non-neutral loci. Finally, higher population divergence yields a more even distribution of outliers along their differentiation range but does not always translate into higher outlier proportions or higher rates in which outliers are matched to coding regions. If repeated in similar systems, observed genomic patterns might reveal speciation signatures in diverse networks of population isolation.

中文翻译：

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同域和异域东北太平洋和科尔特斯海的 Sargo (Anisotremus davidsonii) 和 Longjaw Mudsucker (Gillichthys mirabilis) 种群的基因组差异模式和选择信号

研究隔离如何影响共同分布物种的种群分化和适应，可以让我们更深入地了解景观如何影响生物多样性。Sargo, Anisotremus davidsonii (Haemulidae) 和 Longjaw 泥鳅, Gillichthys mirabilis (Gobiidae) 提供了一个值得注意的框架来研究它们的太平洋种群跨越美国加利福尼亚州 Point Conception 和墨西哥蓬塔尤金尼亚的系统地理学断点等机制，并被下加利福尼亚半岛与科尔特斯海中的那些分开。在这里，使用 RADseq 对来自 48 个 Sargos 和 73 个 mudusuckers 的数千个基因座进行基因分型，以表征整体基因组差异，并基于具有假设不同隔离水平的种群中的异常基因座搜索推定中性和非中性结构的常见模式。我们进一步寻找种群差异与异常值总比例、异常值 FST 分布以及与 GenBank 中编码区域匹配的异常值比例之间的相似之处。在 Mudusucker (FST = 0.15)、Sargo 的 Punta Eugenia (FST = 0.02) 和 Baja California 半岛两侧的两个物种 (FST = 0.11 和 0.23，在 Sargo 和 mudusucker，分别）。每个物种使用中性和非中性基因座显示结构。最后，较高的群体差异会在其分化范围内产生更均匀的异常值分布，但并不总是转化为更高的异常值比例或更高的异常值与编码区域匹配的比率。如果在类似系统中重复，