Theisen T C, Bowen B W, Lanier W, Baldwin J D
Division of Biological Sciences, Florida Atlantic University, 2912 College Avenue, Davie, Florida 33314, USA.
Mol Ecol. 2008 Oct;17(19):4233-47. doi: 10.1111/j.1365-294x.2008.03913.x.
The population genetic structure and phylogeography of wahoo, Acanthocybium solandri, were investigated on a global scale with intron six of lactate dehydrogenase-A (ldhA6, 8 locations, N = 213) and mtDNA cytochrome b (Cytb, 10 locations, N = 322). Results show extensive sharing of haplotypes across the wahoo's entire global range, and analyses were unable to detect significant structure (nuclear F(ST) = 0.0125, P = 0.106; mtDNA Phi(ST) < 0.0001, P = 0.634). Power analyses indicated 95% confidence in detecting nuclear F(ST) > or = 0.0389 and mtDNA Phi(ST) > or = 0.0148. These findings appear unique, as most other tunas, billfishes, and oceanic sharks exhibit significant population structure on the scale of East-West Atlantic, Atlantic vs. Indian-Pacific, or East-West Pacific. Overall nuclear heterozygosity (H = 0.714) and mtDNA haplotype diversity (h = 0.918) are both high in wahoo, while overall mtDNA nucleotide diversity (pi = 0.006) and nuclear nucleotide diversity (pi = 0.004) are uniformly low, indicating a recent increase in population size. Coalescence analyses yield an estimate of effective female population size (NeF) at approximately 816,000, and a population bottleneck approximately 690,000 years ago. However, conclusions about population history from our Cytb data set are not concordant with a control region survey, a finding that will require further investigation. This is the first example of a vertebrate with a single globally distributed population, a finding we attribute to extensive dispersal at all life stages. The indications of a worldwide stock for wahoo reinforce the mandate for international cooperation on fisheries issues.
利用乳酸脱氢酶 - A的内含子6（ldhA6，8个地点，N = 213）和线粒体DNA细胞色素b（Cytb，10个地点，N = 322），在全球范围内对马鲛鱼（Acanthocybium solandri）的种群遗传结构和系统地理学进行了研究。结果显示，马鲛鱼在其全球分布范围内广泛共享单倍型，分析未能检测到显著的结构（核F(ST) = 0.0125，P = 0.106；线粒体DNA Phi(ST) < 0.0001，P = 0.634）。功效分析表明，有95%的把握检测到核F(ST)≥0.0389和线粒体DNA Phi(ST)≥0.0148。这些发现似乎很独特，因为大多数其他金枪鱼、旗鱼和远洋鲨鱼在东西大西洋、大西洋与印度洋 - 太平洋或东西太平洋的尺度上表现出显著的种群结构。马鲛鱼的总体核杂合度（H = 0.714）和线粒体DNA单倍型多样性（h = 0.918）都很高，而总体线粒体DNA核苷酸多样性（pi = 0.006）和核核苷酸多样性（pi = 0.004）均较低，表明种群大小近期有所增加。溯祖分析得出有效雌性交配群体大小（NeF）约为816,000，以及约69万年前的种群瓶颈。然而，我们的Cytb数据集关于种群历史的结论与一个控制区调查不一致，这一发现需要进一步研究。这是具有单一全球分布种群的脊椎动物的首个例子，我们将这一发现归因于在所有生命阶段的广泛扩散。马鲛鱼全球种群的迹象强化了在渔业问题上开展国际合作的必要性。
