Habitat loss and alteration has driven many species into decline, often to the point of requiring protection and intervention to avert extinction. Genomic data provide the opportunity to inform conservation and recovery efforts with details about vital evolutionary processes with a resolution far beyond that of traditional genetic approaches. The tricolored blackbird (Agelaius tricolor) has suffered severe losses during the previous century largely due to anthropogenic impacts on their habitat. Using a dataset composed of a whole genome paired with reduced representation libraries (RAD‐Seq) from samples collected across the species’ range, we find evidence for panmixia using multiple methods, including PCA (no geographic clustering), admixture analyses (ADMIXTURE and TESS conclude K = 1), and comparisons of genetic differentiation (average FST = 0.029). Demographic modeling approaches recovered an ancient decline that had a strong impact on genetic diversity but did not detect any effect from the known recent decline. We also did not detect any evidence for selection, and hence adaptive variation, at any site, either geographic or genomic. These results indicate that species continues to have high vagility across its range despite population decline and habitat loss and should be managed as a single unit.

中文翻译：

---

尽管受威胁的三色黑鸟（Agelaius tricolor）栖息地极度丧失和种群减少，但仍存在持续性混血症

栖息地的丧失和改变导致许多物种的数量减少，常常达到需要保护和干预以免灭绝的地步。基因组数据提供了机会，可以为保护和恢复工作提供重要的进化过程的详细信息，其分辨率远远超出了传统遗传方法的分辨率。三色黑鸟（Agelaius tricolor）在上个世纪以来遭受了严重损失，这主要是由于人为对其栖息地的影响。使用由整个基因组与来自整个物种范围内的样本的简化表示库（RAD-Seq）配对的数据集，我们使用多种方法（包括PCA（无地理聚类），混合分析（ADMIXTURE和TESS）找到泛滥的证据（K = 1），以及遗传分化比较（平均FST = 0.029）。人口建模方法恢复了对遗传多样性有重大影响的古老衰落，但未发现已知的最近衰落带来的任何影响。我们也没有在任何地点（地理或基因组）检测到任何选择证据，因此也没有发现适应性变异。