Comparative biogeography and the evolution of population structure for bottlenose and common dolphins in the Indian Ocean

Abstract Aim: In the marine environment, where there are few physical boundaries to gene flow, there is often nevertheless intraspecific diversity with consequences for effective conservation and management.  Here we compare two closely related dolphin species with a shared distribution in the Indian Ocean (IO) to better understand the biogeographic drivers of their population structure. Location: Global oceans and seas with a focus on the Indian Ocean Taxon: Tursiops sp. and Delphinus sp. Methods: Bayesian, ordination, assignment, statistical and phylogenetic analyses to assess phylogeography, connectivity and population structure using microsatellite and mitochondrial DNA genetic markers. Results: Both Tursiops sp. and Delphinus sp. showed population structure across the western IO and, in each case, populations in the Arabian Sea (off India, Pakistan and Oman) were most differentiated. Comparisons with other populations worldwide revealed independent lineages in this g...摘要 研究目的：在海洋环境中，尽管基因交流几乎不存在物理屏障，但物种内部仍常存在遗传分化，这对高效的物种保护与管理具有重要意义。本研究选取在印度洋（Indian Ocean, IO）共有分布的两种近缘海豚物种，旨在深入解析其种群结构的生物地理驱动机制。 研究区域：全球海洋与海域，重点聚焦印度洋 研究类群：宽吻海豚属（Tursiops sp.）与真海豚属（Delphinus sp.） 研究方法：采用贝叶斯分析、排序分析、群体分配分析、统计分析及系统发育分析，结合微卫星（microsatellite）与线粒体DNA（mitochondrial DNA）遗传标记，对类群的系统地理学特征、种群连通性与种群结构进行评估。 研究结果：宽吻海豚属与真海豚属在西印度洋均表现出显著的种群结构；两类群中，阿拉伯海（印度、巴基斯坦与阿曼外海）的种群均呈现最高的遗传分化水平。通过与全球其他海域种群的对比分析发现，该海域类群形成了独立的演化支系……