Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
Mol Ecol. 2011 Sep;20(18):3894-909. doi: 10.1111/j.1365-294X.2011.05220.x. Epub 2011 Aug 18.
Pleistocene glacial oscillations and associated tectonic processes are believed to have influenced the historical abundances and distribution of organisms in the Asia Northwest Pacific (ANP). Accumulating evidence indicates that factors shaping tempospatial population dynamics and distribution patterns of marine taxa vary with biogeographical latitude, pelagic behaviour and oceanographic regimes. To detect what kinds of historical and contemporary factors affected genetic connectivity, phylogeographic profiles of littoral macroalga Sargassum horneri in the ANP were analysed based on mitochondrial (Cox3) and chloroplast (rbcL) data sets. Five distinct clades were recovered. A strong signature of biogeographical structure was revealed (Φ(CT) = 0.487, P < 0.0001) derived from remarkable differentiation in clade distribution, as clade I is restricted to Chinese marginal seas (Yellow-Bohai Sea, East China Sea and South China Sea), whereas clades II-V are discontinuously scattered around the main Islands of Japan. Furthermore, two secondary contact regions were identified along the south Japan-Pacific coastline. This significant differentiation between the two basins may reflect historical glacial isolation in the northwestern Pacific, which is congruent with the estimates of clade divergence and demographic expansion during the late Quaternary low sea levels. Analysis of molecular variance and the population-pair statistic F(ST) also revealed significant genetic structural differences between Chinese marginal seas and the Japanese basin. This exceptional phylogeographic architecture in S. horneri, initially shaped by historical geographic isolation during the late Pleistocene ice age and physical biogeographical barriers, can be complicated by oceanographic regimes (ocean surface currents) and relocating behaviour such as oceanic drifting.
更新世冰期振荡和相关的构造过程被认为影响了亚洲西北太平洋（ANP）生物的历史丰度和分布。越来越多的证据表明，塑造海洋分类群时空种群动态和分布模式的因素因生物地理纬度、浮游行为和海洋学状态而异。为了检测哪些历史和当代因素影响了遗传连通性，对 ANP 沿岸大型海藻半叶马尾藻（Sargassum horneri）的线粒体（Cox3）和叶绿体（rbcL）数据集进行了系统地理分析。共发现 5 个不同的分支。系统地理结构的强烈特征（Φ（CT）= 0.487，P < 0.0001）揭示了明显的分化，支系分布存在显著差异，因为支系 I 局限于中国边缘海（黄渤海、东海和南海），而支系 II-V 则不连续地散布在日本主要岛屿周围。此外，还在日本南部太平洋海岸线发现了两个次要接触区。这两个盆地之间的明显分化可能反映了西北太平洋的历史冰川隔离，这与晚第四纪低海平面时期支系分歧和种群扩张的估计一致。分子方差分析和种群对统计 F（ST）也揭示了中国边缘海和日本海盆之间的遗传结构差异显著。半叶马尾藻这种独特的系统地理结构最初是由晚更新世冰期的历史地理隔离和物理生物地理障碍塑造的，然后受到海洋学状态（海洋表面流）和洄游行为（如海洋漂流）的影响。
