Anderson Giulia, Hampton John, Smith Neville, Rico Ciro
School of Marine Studies Molecular Analytics Laboratory (MOANA-LAB) Faculty of Science Technology and Environment The University of the South Pacific Suva Fiji.
Oceanic Fisheries Programme (OFP) Pacific Community Nouméa New Caledonia.
Ecol Evol. 2019 Aug 27;9(18):10354-10364. doi: 10.1002/ece3.5554. eCollection 2019 Sep.
Albacore tuna () has a distinctly complex life history in which juveniles and adults separate geographically but at times inhabit the same spaces sequentially. The species also migrates long distances and presumably experiences varied regimes of physical stress over a lifetime. There are, therefore, many opportunities for population structure to arise based on stochastic differences or environmental factors that promote local adaptation. However, with the extent of mobility consistently demonstrated by tagged individuals, there is also a strong argument for panmixia within an ocean basin. It is important to confirm such assumptions from a population genetics standpoint for this species in particular because albacore is one of the principal market tuna species that sustains massive global fisheries and yet is also a slow-growing temperate tuna. Consequently, we used 1,837 neutral SNP loci and 89 loci under potential selection to analyze population genetic structure among five sample groups collected from the western and central South Pacific. We found no evidence to challenge panmixia at neutral loci, but strong indications of structuring at adaptive loci. One population sample, from French Polynesia in 2004, was particularly differentiated. Unfortunately, the current study cannot infer whether the divergence is geographic or temporal, or possibly caused by sample distribution. We encourage future studies to include potentially adaptive loci and to continue fine-scale observations within an ocean basin, and not to assume genome-wide panmixia.
长鳍金枪鱼（）具有明显复杂的生活史，其中幼鱼和成鱼在地理上相互分离，但有时会依次栖息在相同的空间。该物种还会进行长距离洄游，并且在其一生中可能会经历不同的物理压力状态。因此，基于随机差异或促进局部适应的环境因素，种群结构有很多机会形成。然而，鉴于标记个体始终表现出的移动程度，也有强有力的论据支持在一个大洋盆地内存在随机交配。从种群遗传学的角度确认这些假设对于该物种尤为重要，因为长鳍金枪鱼是维持全球大规模渔业的主要市场金枪鱼物种之一，同时也是生长缓慢的温带金枪鱼。因此，我们使用了1837个中性单核苷酸多态性（SNP）位点和89个潜在选择下的位点，来分析从南太平洋西部和中部收集的五个样本组之间的种群遗传结构。我们没有发现证据挑战中性位点的随机交配，但在适应性位点有强烈的结构化迹象。2004年来自法属波利尼西亚 的一个种群样本特别分化。不幸的是，当前的研究无法推断这种分化是地理上的还是时间上的，或者可能是由样本分布引起的。我们鼓励未来的研究纳入潜在的适应性位点，并在一个大洋盆地内继续进行精细尺度的观察，而不要假定全基因组随机交配。
