Inferring the demographic history of European Ficedula flycatcher populations

Background: Inference of population and species histories and population stratification using genetic data is important for discriminating between different speciation scenarios and for correct interpretation of genome scans for signs of adaptive evolution and trait association. Here we use data from 24 intronic loci re-sequenced in population samples of two closely related species, the pied flycatcher and the collared flycatcher. Results: We applied Isolation-Migration models, assignment analyses and estimated the genetic differentiation and diversity between species and between populations within species. The data indicate a divergence time between the species of < 1 million years, significantly shorter than previous estimates using mtDNA, point to a scenario with unidirectional gene-flow from the pied flycatcher into the collared flycatcher and imply that barriers to hybridisation are still permeable in a recently established hybrid zone. Furthermore, we detect significant populat...

背景：利用遗传数据推断种群与物种演化历史以及种群分层结构，对于区分不同的物种形成场景、正确解读全基因组扫描所发现的适应性进化信号与性状关联具有重要意义。本研究使用了两个近缘物种——斑姬鹟（pied flycatcher）与领姬鹟（collared flycatcher）的种群样本中24个内含子位点的重测序数据。结果：我们采用隔离迁移（Isolation-Migration）模型、归属分析方法，估算了物种间以及物种种群内的遗传分化与遗传多样性水平。数据显示两个物种的分化时间不足100万年，显著短于此前基于线粒体DNA（mtDNA）得到的估算结果；研究结果指向斑姬鹟向领姬鹟存在单向基因流的演化场景，并表明在新近形成的杂交带中，杂交障碍仍具有可渗透性。此外，我们检测到显著的种群...