Genetic Diversity in a Deep-Sea Harpacticoid Copepod Found Near Two Oil-Drilling Sites in the Gulf of Mexico
Genetic Diversity in a Deep-Sea Harpacticoid Copepod Found Near Two Oil-Drilling Sites in the Gulf of Mexico
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在墨西哥湾两个石油钻探地点附近发现的深海 Harpacticoid 桡足类动物的遗传多样性
DOI：
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
J. Fleeger
中科院分区：
文献类型：
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作者：
Christopher S. Gregg;D. Foltz;J. Fleeger
摘要在路易斯安那州海岸外墨西哥湾北方的两个地点，对邻近（近场）和远离（远场）石油钻井平台的地点进行了harpacticoid桡足类的采样，两个地点的深度均为1100 m。这些地点位于花园银行地区602区（GB 602）和密西西比峡谷地区292区（MC 292）。在这两个地点的近场地点的特点是大量的单一的未描述的种类的harpacticoid桡足类，深足蚤属，但这种物种在远场地区基本上不存在。我们测序了线粒体细胞色素c氧化酶亚基I基因（考克斯I）的710 bp的部分，以分析在两个平台的Bathycletopsyllus sp.的遗传多样性和种群结构，并确定是否harpacticoids检查是一个单一的物种，或一个复杂的隐蔽物种。我们发现，在考克斯I基因（最大1.6%）的分歧是在观察到的范围内的种内变异性在以前研究的种类的harpacticoid桡足类，以及其特征在于分类。因此，这里分析的两个样品是单一种属，而不是复杂的神秘种属。此外，两个样本之间存在显著的遗传异质性，表明两个地点之间的基因流动有限。这是预期的，因为Harpacticoids的典型低扩散潜力和站点之间的距离（407公里）。最后，GB 602样本中的单倍型多样性和核苷酸多样性都很低，与纯中性模型存在名义上的显着偏离。这一结果可能表明选择性扫描，时间种群规模变化或其他过程不包括在中性模型的发生。相比之下，MC 292样本的单倍型多样性和核苷酸多样性均高于Garden Banks样本，并且没有检测到偏离中性。对于这两个样本，在单倍型和核苷酸水平的多样性在浅水hapacticoid物种栖息在未污染和污染的淤泥质沉积物的范围内，所以没有证据表明在本研究中的污染相关的影响。
Abstract Sites adjacent to (near-field) and distant from (far-field) oil-drilling platforms were sampled for harpacticoid copepods at two locations in the northern Gulf of Mexico off the coast of Louisiana, both at depths of ≈ 1100 m. The sites were located at Garden Banks Area Block 602 (GB 602) and Mississippi Canyon Area Block 292 (MC 292). Near-field sites at both locations were characterized by large numbers of a single undescribed species of harpacticoid copepod, Bathycletopsyllus sp., but this species was essentially absent from far-field sites. We sequenced a 710 bp portion of the mitochondrial cytochrome c oxidase subunit I gene (COX I) to analyze the genetic diversity and population structure of Bathycletopsyllus sp. at the two platforms, and to determine if the harpacticoids examined were either a single species, or a complex of cryptic species. We found that divergence at the COX I gene (maximum 1.6%) was within the range observed for intraspecific variability in previously-studied species of harpacticoid copepods that were well-characterized taxonomically. Thus, the two samples analyzed here were a single species and not a complex of cryptic species. In addition, there was significant genetic heterogeneity between the two samples, suggesting limited gene flow between the two sites. This was expected given the low dispersal potential typical of harpacticoids and the distance between the sites (407 km). Lastly, haplotype diversity and nucleotide diversity were both low in the GB 602 sample, giving a nominally-significant departure from a pure neutral model. This result could indicate the occurrence of selective sweeps, temporal population size variation or other processes not included in the neutral model. In contrast, haplotype diversity and nucleotide diversity were both higher in the MC 292 sample than at Garden Banks, and there was no detectable departure from neutrality. For both samples, diversity at the haplotype and nucleotide levels were within the range seen in shallow-water harpacticoid species inhabiting both uncontaminated and contaminated muddy sediments, so there was no evidence for pollution related effects in the present study.
影响因子：
3.3
作者：
L. Excoffier;P. Smouse;J. Quattro
通讯作者：
L. Excoffier;P. Smouse;J. Quattro