title: The spatial scale of genetic subdivision in populations of Ifremeria nautilei, a hydrothermal-vent gastropod from the southwest Pacific.
abstract: BACKGROUND
  Deep-sea hydrothermal vents provide patchy, ephemeral habitats for specialized communities of animals that depend on chemoautotrophic primary production. Unlike eastern Pacific hydrothermal vents, where population structure has been studied at large (thousands of kilometres) and small (hundreds of meters) spatial scales, population structure of western Pacific vents has received limited attention. This study addresses the scale at which genetic differentiation occurs among populations of a western Pacific vent-restricted gastropod, Ifremeria nautilei.
  
  
  RESULTS
  We used mitochondrial and DNA microsatellite markers to infer patterns of gene flow and population subdivision. A nested sampling strategy was employed to compare genetic diversity in discrete patches of Ifremeria nautilei separated by a few meters within a single vent field to distances as great as several thousand kilometres between back-arc basins that encompass the known range of the species. No genetic subdivisions were detected among patches, mounds, or sites within Manus Basin. Although I. nautilei from Lau and North Fiji Basins (~1000 km apart) also exhibited no evidence for genetic subdivision, these populations were genetically distinct from the Manus Basin population.
  
  
  CONCLUSIONS
  An unknown process that restricts contemporary gene flow isolates the Manus Basin population of Ifremeria nautilei from widespread populations that occupy the North Fiji and Lau Basins. A robust understanding of the genetic structure of hydrothermal vent populations at multiple spatial scales defines natural conservation units and can help minimize loss of genetic diversity in situations where human activities are proposed and managed.
authors.affiliation: Marine Laboratory, Nicholas School of the Environment, Duke University, Beaufort, NC 28516, USA. andrew.david.thaler@gmail.com
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Thaler
authors.forename: Kevin
authors.initials: K
authors.lastname: Zelnio
authors.forename: William
authors.initials: W
authors.lastname: Saleu
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Schultz
authors.forename: Jens
authors.initials: J
authors.lastname: Carlsson
authors.forename: Clifford
authors.initials: C
authors.lastname: Cunningham
authors.forename: Robert C
authors.initials: RC
authors.lastname: Vrijenhoek
authors.forename: Cindy L
authors.initials: CL
authors.lastname: Van Dover
mesh_terms: D000818:Animals; D004272:DNA, Mitochondrial / Q000235:genetics; D049851:Gastropoda / Q000145:classification / Q000235:genetics*; D005819:Genetic Markers; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D060086:Hydrothermal Vents; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D010140:Pacific Ocean; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial; D005819:Genetic Markers