Jensen Ashley M, O'Neil Nicholas P, Iwaniuk Andrew N, Burg Theresa M
Department of Biological Sciences University of Lethbridge Lethbridge Alberta Canada.
Canadian Centre for Behavioural Neuroscience University of Lethbridge Lethbridge Alberta Canada.
Ecol Evol. 2019 May 1;9(10):5572-5592. doi: 10.1002/ece3.5112. eCollection 2019 May.
The amount of dispersal that occurs among populations can be limited by landscape heterogeneity, which is often due to both natural processes and anthropogenic activity leading to habitat loss or fragmentation. Understanding how populations are structured and mapping existing dispersal corridors among populations is imperative to both determining contemporary forces mediating population connectivity, and informing proper management of species with fragmented populations. Furthermore, the contemporary processes mediating gene flow across heterogeneous landscapes on a large scale are understudied, particularly with respect to widespread species. This study focuses on a widespread game bird, the Ruffed Grouse (), for which we analyzed samples from the western extent of the range. Using three types of genetic markers, we uncovered multiple factors acting in concert that are responsible for mediating contemporary population connectivity in this species. Multiple genetically distinct groups were detected; microsatellite markers revealed six groups, and a mitochondrial marker revealed four. Many populations of Ruffed Grouse are genetically isolated, likely by macrogeographic barriers. Furthermore, the addition of landscape genetic methods not only corroborated genetic structure results, but also uncovered compelling evidence that dispersal resistance created by areas of unsuitable habitat is the most important factor mediating population connectivity among the sampled populations. This research has important implications for both our study species and other inhabitants of the early successional forest habitat preferred by Ruffed Grouse. Moreover, it adds to a growing body of evidence that isolation by resistance is more prevalent in shaping population structure of widespread species than previously thought.
种群间发生的扩散量可能会受到景观异质性的限制，景观异质性通常是由自然过程和人为活动共同导致的，这些活动会造成栖息地丧失或破碎化。了解种群的结构以及绘制种群间现有的扩散廊道，对于确定影响种群连通性的当代因素以及为管理种群破碎化的物种提供恰当的指导都至关重要。此外，目前对大规模介导基因流穿过异质景观的当代过程研究不足，尤其是对于分布广泛的物种。本研究聚焦于一种分布广泛的猎禽——披肩榛鸡（学名：Bonasa umbellus），我们分析了该物种分布范围西部的样本。通过使用三种类型的遗传标记，我们发现了多个共同作用的因素，这些因素负责介导该物种当代的种群连通性。检测到多个遗传上不同的群体；微卫星标记揭示了六个群体，线粒体标记揭示了四个群体。许多披肩榛鸡种群在遗传上是隔离的，可能是由于宏观地理屏障。此外，景观遗传学方法的应用不仅证实了遗传结构的结果，还揭示了令人信服的证据，即由不适合栖息地区域造成的扩散阻力是介导抽样种群间种群连通性的最重要因素。这项研究对于我们的研究物种以及披肩榛鸡所偏好的早期演替森林栖息地的其他栖息者都具有重要意义。此外，它还增加了越来越多的证据，表明抗性隔离在塑造分布广泛物种的种群结构方面比以前认为的更为普遍。
