Cosmopolitan marine pelagic species display variable patterns of population connectivity among the world’s major oceans. While this information is crucial for informing management, information is lacking for many ecologically important species, including apex predators. In this study we examine patterns of genetic structure in the broadnose sevengill shark, Notorynchus cepedianus across its global distribution. We estimate patterns of connectivity among broadnose sevengill shark populations from three major oceanic regions (South Atlantic, Oceania and Eastern Pacific) by contrasting mitochondrial and nuclear DNA haplotype frequencies. We also produced time calibrated Bayesian Inference phylogenetic reconstructions to analyses global phylogeographic patterns and estimate divergence times among distinctive shark lineages. Our results demonstrate significant genetic differentiation among oceanic regions (Φ_ST = 0.9789, P < 0.0001) and a lack of genetic structuring within regions (Φ_ST = − 0.007; P = 0.479). Time calibrated Bayesian Inference phylogenetic reconstructions indicate that the observed patterns of genetic structure among oceanic regions are historical, with regional populations estimated to have diverged from a common ancestor during the early to mid-Pleistocene. Our results indicate significant genetic structuring and a lack of gene flow among broadnose sevengill shark populations from the South Atlantic, Oceania and Eastern Pacific regions. Evidence of deep lineage divergences coinciding with the early to mid-Pleistocene suggests historical glacial cycling has contributed to the vicariant divergence of broadnose sevengill shark populations from different ocean basins. These finding will help inform global management of broadnose sevengill shark populations, and provides new insights into historical and contemporary evolutionary processes shaping populations of this ecologically important apex predator.

大都会海洋中上层鱼类在世界各主要海洋之间显示出不同的种群连通性模式。尽管此信息对于告知管理至关重要，但许多生态上重要的物种（包括先头天敌）都缺乏信息。在这项研究中，我们研究了宽鼻七g鲨（Notorynchus cepedianus）的遗传结构模式遍及全球 通过对比线粒体和核DNA单倍型频率，我们估计了来自三个主要海洋地区（南大西洋，大洋洲和东太平洋）的宽鳍七g鲨种群之间的连通性模式。我们还制作了经过时间校准的贝叶斯推断系统发育重构，以分析全球系统地理模式并估计不同鲨鱼谱系之间的发散时间。我们的结果证明海洋区域（间显著遗传分化Φ _ST  = 0.9789，P  <0.0001）和区域内缺乏遗传结构化的（Φ _ST  = - 0.007; P = 0.479）。时间校准的贝叶斯推断系统发育重建表明，在大洋区域中观察到的遗传结构模式是历史性的，在更新世早期至中期，区域种群估计与共同祖先背道而驰。我们的结果表明，来自南大西洋，大洋洲和东太平洋地区的宽鼻七seven鲨种群之间存在显着的遗传结构，并且缺乏基因流。与更新世早期至中期相一致的深层谱系差异的证据表明，历史上的冰川循环促成了来自不同海盆的阔鼻七g鲨种群的异族分化。这些发现将有助于为全球管理七seven鲨种群的全球管理提供依据，。