Gene Flow and Isolation in the Arid Nearctic Revealed by Genomic Analyses of Desert Spiny Lizards.
Gene Flow and Isolation in the Arid Nearctic Revealed by Genomic Analyses of Desert Spiny Lizards.
复制标题
沙漠刺蜥蜴的基因组分析揭示了干旱近极地区的基因流和隔离。
DOI：
10.1093/sysbio/syae001
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发表时间：
2024
影响因子：
6.5
通讯作者：
Pavón-Vázquez CJ
中科院分区：
文献类型：
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作者：
Pavón-Vázquez CJ
基因流动和基因隔离的对立力量是形成遗传多样性的两个主要过程。了解这些在空间和时间上是如何变化的，对于确定促进多样化的环境特征是必要的。在干旱的新北极地区的分类群中发现了相当大的地理结构，促使人们对该地区隔离的驱动因素进行了研究。一些地理特征被认为是基因流动的障碍，包括科罗拉多河、西部大陆分水岭（WCD）和假定的中半岛下加利福尼亚州的海道。然而，最近的研究表明，与其他分化机制相比，屏障在遗传分化中的作用可能被高估了。在这项研究中，我们推断了沙漠刺蜥（Sceloporus magister）和巴哈刺蜥（Sceloporus zosteromus）的连通性和隔离性的历史和空间格局，它们共同构成了一个由异鸟谱系组成的物种complex，在北美西部干旱地区分布广泛。我们的分析结合了线粒体序列、基因组规模数据以及过去和现在的气候数据，以评估该地区基因流动障碍的性质和强度。我们的方法依赖于对多物种融合下的迁移的估计，以了解面对基因流动的谱系分化的历史。结果表明：Magistercomplex是地理结构的，但我们也发现了基因流动的实例。WCD是基因流动的强大屏障，而科罗拉多河更具渗透性。分析对半岛谱系分化的催化剂产生了矛盾的结果。zosteromus。我们的研究表明，对完全采样的物种的大规模基因组数据可以为生物地理学带来新的启示。此外，我们的方法强调需要对多种证据来源进行综合分析，以充分表征差异的驱动因素。
The opposing forces of gene flow and isolation are two major processes shaping genetic diversity. Understanding how these vary across space and time is necessary to identify the environmental features that promote diversification. The detection of considerable geographic structure in taxa from the arid Nearctic has prompted research into the drivers of isolation in the region. Several geographic features have been proposed as barriers to gene flow, including the Colorado River, Western Continental Divide (WCD), and a hypothetical Mid-Peninsular Seaway in Baja California. However, recent studies suggest that the role of barriers in genetic differentiation may have been overestimated when compared to other mechanisms of divergence. In this study, we infer historical and spatial patterns of connectivity and isolation in Desert Spiny Lizards (Sceloporus magister) and Baja Spiny Lizards (Sceloporus zosteromus), which together form a species complex composed of parapatric lineages with wide distributions in arid western North America. Our analyses incorporate mitochondrial sequences, genomic-scale data, and past and present climatic data to evaluate the nature and strength of barriers to gene flow in the region. Our approach relies on estimates of migration under the multispecies coalescent to understand the history of lineage divergence in the face of gene flow. Results show that theS.magistercomplex is geographically structured, but we also detect instances of gene flow. The WCD is a strong barrier to gene flow, while the Colorado River is more permeable. Analyses yield conflicting results for the catalyst of differentiation of peninsular lineages inS. zosteromus. Our study shows how large-scale genomic data for thoroughly sampled species can shed new light on biogeography. Furthermore, our approach highlights the need for the combined analysis of multiple sources of evidence to adequately characterize the drivers of divergence.