Department of Zoology & Physiology, University of Wyoming, Laramie, WY, United States.
University of Wyoming Program in Ecology, Laramie, WY, United States.
Evolution. 2024 Oct 28;78(11):1774-1789. doi: 10.1093/evolut/qpae118.
Describing how hybrid zones respond to anthropogenic influence can illuminate how the environment regulates both species distributions and reproductive isolation between species. In this study, we analyzed specimens collected from the Passerina cyanea×P. amoena hybrid zone between 2004 and 2007 and between 2019 and 2021 to explore changes in genetic structure over time. This comparison follows a previous study that identified a significant westward shift of the Passerina hybrid zone during the latter half of the twentieth century. A second temporal comparison of hybrid zone genetic structure presents unique potential to describe finer-scale dynamics and to identify potential mechanisms of observed changes more accurately. After concluding that the westward movement of the Passerina hybrid zone has accelerated in recent decades, we investigated potential drivers of this trend by modeling the influence of bioclimatic and landcover variables on genetic structure. We also incorporated eBird data to determine how the distributions of P. cyanea and P. amoena have responded to recent climate and landcover changes. We found that the distribution of P. cyanea in the northern Great Plains has shifted west to track a moving climatic niche, supporting anthropogenic climate change as a key mediator of introgression in this system.
描述杂种区如何响应人为影响可以阐明环境如何调节物种的分布和物种之间的生殖隔离。在这项研究中，我们分析了 2004 年至 2007 年以及 2019 年至 2021 年间采集的 Passerina cyanea×P. amoena 杂种区的标本，以探索遗传结构随时间的变化。这项比较是在先前的一项研究之后进行的，该研究确定了 Passerina 杂种区在 20 世纪后半叶向西显著移动。第二次对杂种区遗传结构的时间比较具有独特的潜力，可以更准确地描述更细微的动态，并确定观察到的变化的潜在机制。在得出 Passerina 杂种区向西移动在最近几十年加速的结论后，我们通过模拟生物气候和土地覆盖变量对遗传结构的影响来研究这种趋势的潜在驱动因素。我们还结合了 eBird 数据来确定 P. cyanea 和 P. amoena 的分布如何响应最近的气候和土地覆盖变化。我们发现，大平原北部的 P. cyanea 分布已经向西移动，以跟踪不断变化的气候生态位，这支持人为气候变化是该系统基因渐渗的关键中介。
