Department of Wildlife and Fisheries Sciences and Texas Cooperative Wildlife Collections, Texas A&M University, College Station, TX, 77843, USA.
Mol Ecol. 2013 Jun;22(12):3333-44. doi: 10.1111/mec.12305. Epub 2013 May 25.
The evolution of migration in birds has fascinated biologists for centuries. In this study, we performed phylogenetic-based analyses of Catharus thrushes, a model genus in the study of avian migration, and their close relatives. For these analyses, we used both mitochondrial and nuclear genes, and the resulting phylogenies were used to trace migratory traits and biogeographic patterns. Our results provide the first robust assessment of relationships within Catharus and relatives and indicate that both mitochondrial and autosomal genes contribute to overall support of the phylogeny. Measures of phylogenetic informativeness indicated that mitochondrial genes provided more signal within Catharus than did nuclear genes, whereas nuclear loci provided more signal for relationships between Catharus and close relatives than did mitochondrial genes. Insertion and deletion events also contributed important support across the phylogeny. Across all taxa included in the study, and for Catharus, possession of long-distance migration is reconstructed as the ancestral condition, and a North American (north of Mexico) ancestral area is inferred. Within Catharus, sedentary behaviour evolved after the first speciation event in the genus and is geographically and temporally correlated with Central American distributions and the final closure of the Central American Seaway. Migratory behaviour subsequently evolved twice in Catharus and is geographically and temporally correlated with a recolonization of North America in the late Pleistocene. By temporally linking speciation events with changes in migratory condition and events in Earth history, we are able to show support for several competing hypotheses relating to the geographic origin of migration.
鸟类迁徙的进化几百年来一直吸引着生物学家。在这项研究中，我们对画眉鸟（迁徙鸟类研究的模式属）及其近缘种进行了基于系统发育的分析。我们使用了线粒体和核基因进行这些分析，所得的系统发育树用于追踪迁徙特征和生物地理模式。我们的研究结果首次对画眉鸟及其近缘种的内部关系进行了稳健评估，并表明线粒体和常染色体基因都有助于整体支持系统发育。系统发育信息量的衡量标准表明，线粒体基因在画眉鸟内部提供的信号比核基因多，而核基因在画眉鸟与其近缘种之间的关系上提供的信号比线粒体基因多。插入和缺失事件也在整个系统发育树上提供了重要的支持。在研究中包括的所有分类群中，长距离迁徙被重建为祖先状态，并且推断出北美的（墨西哥以北）祖先区域。在画眉鸟内部，久坐行为在属内的第一次物种形成事件之后进化而来，并且与中美洲的分布和中美洲海道的最终关闭在地理和时间上相关。迁徙行为随后在画眉鸟中进化了两次，并且与更新世晚期北美的重新殖民化在地理和时间上相关。通过将物种形成事件与迁徙状态和地球历史事件在时间上联系起来，我们能够为几个与迁徙起源相关的竞争假说提供支持。
