Genetic diversity and demographic instability in Riftia pachyptilatubeworms from eastern Pacific hydrothermal vents

BMC Evolutionary Biology

Research Article

Stephen A Karl¹  Richard A Lutz²  Robert C Vrijenhoek³  Shannon B Johnson³  D Katharine Coykendall⁴ 

[1] Hawai`i Institute of Marine Biology, University of Hawai`i, Mānoa, Kāne`ohe, HI, USA;Institute of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, USA;Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA;USGS-Leetown Science Center, Aquatic Ecology Branch, Kearneysville, WV, USA;

关键词: Annelida;    Polychaeta;    Siboglinidae;    vent;    metapopulations;   

DOI  :  10.1186/1471-2148-11-96

 received in 2010-11-05, accepted in 2011-04-13,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundDeep-sea hydrothermal vent animals occupy patchy and ephemeral habitats supported by chemosynthetic primary production. Volcanic and tectonic activities controlling the turnover of these habitats contribute to demographic instability that erodes genetic variation within and among colonies of these animals. We examined DNA sequences from one mitochondrial and three nuclear gene loci to assess genetic diversity in the siboglinid tubeworm, Riftia pachyptila, a widely distributed constituent of vents along the East Pacific Rise and Galápagos Rift.ResultsGenetic differentiation (FST) among populations increased with geographical distances, as expected under a linear stepping-stone model of dispersal. Low levels of DNA sequence diversity occurred at all four loci, allowing us to exclude the hypothesis that an idiosyncratic selective sweep eliminated mitochondrial diversity alone. Total gene diversity declined with tectonic spreading rates. The southernmost populations, which are subjected to superfast spreading rates and high probabilities of extinction, are relatively homogenous genetically.ConclusionsCompared to other vent species, DNA sequence diversity is extremely low in R. pachyptila. Though its dispersal abilities appear to be effective, the low diversity, particularly in southern hemisphere populations, is consistent with frequent local extinction and (re)colonization events.

【 授权许可】

Unknown   
© Coykendall et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.