Abstract：
The white shark (Carcharodon carcharias) (Linnaeus, 1758), an iconic apex predator occurring in all oceans,1,2 is classified as Vulnerable globally3-with global abundance having dropped to 63% of 1970s estimates,4-and as Critically Endangered in Europe.5 Identification of evolutionary significant units and their management are crucial for conservation,6 especially as the white shark is facing various but often region-specific anthropogenic threats.7,8,9,10,11 Assessing connectivity in a cosmopolitan marine species requires worldwide sampling and high-resolution genetic markers.12 Both are lacking for the white shark, with studies to date typified by numerous but geographically limited sampling, and analyses relying largely on relatively small numbers of nuclear microsatellites,13,14,15,16,17,18,19 which can be plagued by various genotyping artefacts and thus require cautious interpretation.20 Sequencing and computational advances are finally allowing genomes21,22,23 to be leveraged into population studies,24,25,26,27 with datasets comprising thousands of single-nucleotide polymorphisms (SNPs). Here, combining target gene capture (TGC)28 sequencing (89 individuals, 4,000 SNPs) and whole-genome re-sequencing (17 individuals, 391,000 SNPs) with worldwide sampling across most of the distributional range, we identify three genetically distinct allopatric lineages (North Atlantic, Indo-Pacific, and North Pacific). These diverged 100,000-200,000 years ago during the Penultimate Glaciation, when low sea levels, different ocean currents, and water temperatures produced significant biogeographic barriers. Our results show that without high-resolution genomic analyses of samples representative of a species\' range,12 the true extent of diversity, presence of past and contemporary barriers to gene flow, subsequent speciation, and local evolutionary events will remain enigmatic.
摘要：
白鲨（Carcharodoncarcharias）（Linnaeus，1758),出现在所有海洋中的标志性顶点捕食者，1,2被归类为全球脆弱3-全球丰度已降至20世纪70年代估计的63%，4-在欧洲极为濒危。5识别进化的重要单位及其管理对于保护至关重要，6尤其是当白鲨面临各种但通常是特定地区的人为威胁时。7,8,9,10,11评估世界性海洋物种的连通性需要全球采样和高分辨率遗传标记。迄今为止的研究以众多但地理有限的抽样为代表，和分析主要依赖于相对少量的核微卫星，13,14,15,16,17,18,19这可能会受到各种基因分型伪影的困扰，因此需要谨慎的解释。20测序和计算的进步最终允许基因21,22,23被利用到人口研究中，具有包含数千个单核苷酸多态性(SNP)的数据集的24,25,26,27。这里,结合靶基因捕获(TGC)28个测序(89个个体，4,000个SNP）和全基因组重新测序（17个个体，391,000个SNP)，在大部分分布范围内进行全球抽样，我们确定了三个遗传上不同的异源谱系(北大西洋，印度-太平洋,和北太平洋）。这些在倒数第二个冰川期间在100,000-200,000年前发生了分歧，当海平面低时，不同的洋流，和水温产生了显著的生物地理障碍。我们的结果表明，如果没有对代表物种范围的样本进行高分辨率基因组分析，12多样性的真实程度，过去和当代的基因流动障碍的存在，随后的物种形成，局部进化事件仍将是个谜.
