Castilho Rita, Cunha Regina L, Faria Cláudia, Velasco Eva M, Robalo Joana I
Center of Marine Sciences (CCMAR), University of Algarve, Faro, Portugal.
Instituto de Educação da Universidade de Lisboa, Lisboa, Portugal.
PeerJ. 2017 Apr 27;5:e3195. doi: 10.7717/peerj.3195. eCollection 2017.
Transition zones are of high evolutionary interest because unique patterns of spatial variation are often retained. Here, we investigated the phylogeography of the peacock blenny, , a small marine intertidal fish that inhabits rocky habitats of the Mediterranean and the adjacent Atlantic Ocean. We screened 170 individuals using mitochondrial and nuclear sequence data from eight locations. Four models of genetic structure were tested: panmixia, isolation-by-distance, secondary contact and phylogeographic break. Results indicated clear asymmetric migration from the Mediterranean to the Atlantic but only marginally supported the isolation-by-distance model. Additionally, the species displays an imprint of demographic expansion compatible with the last glacial maximum. Although the existence of a refugium in the Mediterranean cannot be discarded, the ancestral lineage most likely originated in the Atlantic, where most of the genetic diversity occurs.
过渡区域具有很高的进化研究价值，因为独特的空间变异模式常常得以保留。在此，我们研究了孔雀鳚（一种小型海洋潮间带鱼类，栖息于地中海及相邻大西洋的岩石栖息地）的系统地理学。我们利用来自八个地点的线粒体和核序列数据对170个个体进行了筛选。测试了四种遗传结构模型：随机交配、距离隔离、二次接触和系统地理间断。结果表明存在从地中海到大西洋的明显不对称迁移，但仅微弱支持距离隔离模型。此外，该物种显示出与末次盛冰期相符的种群扩张印记。虽然不能排除地中海存在避难所的可能性，但祖先谱系很可能起源于大西洋，那里存在着大部分的遗传多样性。
