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Population genomics reveals seahorses (Hippocampus erectus) of the western mid-Atlantic coast to be residents rather than vagrants - PubMed

  • ️Thu Jan 01 2015

Population genomics reveals seahorses (Hippocampus erectus) of the western mid-Atlantic coast to be residents rather than vagrants

J T Boehm et al. PLoS One. 2015.

Abstract

Understanding population structure and areas of demographic persistence and transients is critical for effective species management. However, direct observational evidence to address the geographic scale and delineation of ephemeral or persistent populations for many marine fishes is limited. The Lined seahorse (Hippocampus erectus) can be commonly found in three western Atlantic zoogeographic provinces, though inhabitants of the temperate northern Virginia Province are often considered tropical vagrants that only arrive during warm seasons from the southern provinces and perish as temperatures decline. Although genetics can locate regions of historical population persistence and isolation, previous evidence of Virginia Province persistence is only provisional due to limited genetic sampling (i.e., mitochondrial DNA and five nuclear loci). To test alternative hypotheses of historical persistence versus the ephemerality of a northern Virginia Province population we used a RADseq generated dataset consisting of 11,708 single nucleotide polymorphisms (SNP) sampled from individuals collected from the eastern Gulf of Mexico to Long Island, NY. Concordant results from genomic analyses all infer three genetically divergent subpopulations, and strongly support Virginia Province inhabitants as a genetically diverged and a historically persistent ancestral gene pool. These results suggest that individuals that emerge in coastal areas during the warm season can be considered "local" and supports offshore migration during the colder months. This research demonstrates how a large number of genes sampled across a geographical range can capture the diversity of coalescent histories (across loci) while inferring population history. Moreover, these results clearly demonstrate the utility of population genomic data to infer peripheral subpopulation persistence in difficult-to-observe species.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Map of zoogeographic provinces, collection sites, and temperature variance.

Contrasting ocean minimum sea surface temperatures across zoogeographic provinces: generated in ARCGIS v.9.3 using the Bio-ORACLE long-term climatic dataset [67]. Collection sites from the northeastern Gulf of Mexico to New York State indicated by diamonds: Apalachicola, Tampa Bay-Charlotte Harbor, Florida Keys, Indian River Lagoon and Jacksonville, FL., Chesapeake Bay, New Jersey-New York.

Figure 2
Figure 2. Genomic variation across individuals and subpopulations.

(a) Treemix population tree with branch lengths scaled to the amount of genetic drift between regions and inferred proportion of genetic admixture (m = 2) between southern and northern regions represented by arrows. Dotted lines do not represent branch length. (b) Principle component analysis. Black circles = Chesapeake Bay-New York, dark grey circles = Florida Atlantic coast, and light grey circles = Gulf of Mexico-Florida Keys. Pie diagrams (a) represent ancestry coefficient proportions derived from the sNMF ancestry plot (c). Each line of the sNMF plot represents one individual.

Figure 3
Figure 3. Distribution of heterozygote and singleton genotypes.

Boxplots represent the range of observed heterozygote genotypes (a) and singleton genotypes per individual/per subpopulation (b).

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References

    1. Briggs PT, Waldman JR (2002) Annotated list of fishes reported from the marine waters of New York. Northeast Nat 9: 47–80.
    1. Curran M (1989) Occurrence of tropical fishes in New England waters. AAUS. 71–82.
    1. Teixeira R, Musick J (2001) Reproduction and food habits of the lined seahorse, Hippocampus erectus (Teleostei: Syngnathidae) of Chesapeake Bay, Virginia. Rev Bras Biol 61: 79–90. - PubMed
    1. Milstein CB, Thomas DL (1976) Fishes New or Uncommon to the New Jersey Coast. Chesap Sci 17: 198.
    1. Briggs JC, Bowen BW (2012) A realignment of marine biogeographic provinces with particular reference to fish distributions. J Biogeogr 39: 12–30. 10.1111/j.1365-2699.2011.02613.x - DOI

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Grants and funding

The National Science Foundation (40C33-00-01) supported the dissertational research of J. T. B. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.