Handling Editor: Luis Valente Abstract Aim: Lineage fusion (merging of two or more populations of a species resulting in a single panmictic group) is a special case of secondary contact. It has the potential to counteract diversification and speciation, or to facilitate it through creation of novel genotypes. Understanding the prevalence of lineage fusion in nature requires reliable detection of it, such that efficient summary statistics are needed. Here, we report on simulations that characterized the initial intensity and subsequent decay of signatures of past fusion for 17 summary statistics applicable to DNA sequence haplotype data. Location: Global. Taxa: Diploid out-crossing species. Methods: We considered a range of scenarios that could reveal the impacts of different combinations of read length versus number of loci (arrangement of DNA sequence data), and whether or not pre-fusion populations experienced bottlenecks coinciding with their divergence (historical context of fusion). Post-fusion gene pools were sampled along 10 successive time points representing increasing lag times following merging of sister populations, and summary statistic values were recalculated at each. Results: Many summary statistics were able to detect signatures of complete merging of populations after a sampling lag time of 1.5 Ne generations, but the most informative ones included two neutrality tests and four diversity metrics, with ZnS (a linkage disequilibrium-based neutrality test) being particularly powerful. Correlation was relatively low among the two neutrality tests and two of the diversity metrics. There were clear benefits of many short (200-bp × 200) loci over a handful of long (4-kb × 10) loci. Also, only the latter genetic dataset type showed impacts of bottlenecks during divergence upon the number of informative summary statistics. Main conclusions: This work contributes to identifying cases of lineage fusion, and advances phylogeography by enabling more nuanced reconstructions of how individual species, or multiple members of an ecological community, responded to past environmental change.

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从系统地理学数据集中检测谱系融合的有效汇总统计

处理编辑：Luis Valente 摘要 目的：谱系融合（一个物种的两个或多个种群的合并导致一个单一的群体）是二次接触的特例。它有可能抵消多样化和物种形成，或通过创造新的基因型来促进多样化和物种形成。了解自然界中谱系融合的流行需要对其进行可靠检测，因此需要有效的汇总统计。在这里，我们报告了模拟，这些模拟表征了过去融合特征的初始强度和随后衰减，适用于 DNA 序列单倍型数据的 17 个汇总统计数据。地点：全球。分类群：二倍体异交物种。方法：我们考虑了一系列场景，这些场景可以揭示读取长度与基因座数量（DNA 序列数据的排列）的不同组合的影响，以及融合前种群是否遇到与其分歧一致的瓶颈（融合的历史背景）。融合后基因库沿 10 个连续时间点采样，代表姐妹群体合并后增加的滞后时间，并在每个时间点重新计算汇总统计值。结果：许多汇总统计数据能够在 1.5 Ne 代的采样滞后时间后检测到种群完全合并的特征，但信息量最大的包括两个中性测试和四个多样性指标，以及 ZnS（基于连锁不平衡的中性测试）特别强大。两个中立性测试和两个多样性指标之间的相关性相对较低。许多短 (200-bp × 200) 基因座明显优于少数长 (4-kb × 10) 基因座。此外，只有后一种遗传数据集类型显示了分歧期间瓶颈对信息汇总统计数量的影响。主要结论：这项工作有助于确定谱系融合的案例，并通过更细致地重建单个物种或生态群落的多个成员如何应对过去的环境变化来推进系统地理学。只有后一种遗传数据集类型显示了分歧期间瓶颈对信息汇总统计数量的影响。主要结论：这项工作有助于确定谱系融合的案例，并通过更细致地重建单个物种或生态群落的多个成员如何应对过去的环境变化来推进系统地理学。只有后一种遗传数据集类型显示了分歧期间瓶颈对信息汇总统计数量的影响。主要结论：这项工作有助于确定谱系融合的案例，并通过更细致地重建单个物种或生态群落的多个成员如何应对过去的环境变化来推进系统地理学。