Document Type

Article

Department/Program

Virginia Institute of Marine Science

Publication Date

12-13-2018

Journal

Biological Journal of the Linnean Society

Volume

126

Issue

2

First Page

289

Last Page

303

Abstract

The existence of strong genetic structure is expected in species with limited ability to disperse and philopatric behaviour. These life-history traits are found in many small benthic elasmobranchs, such as in the small-spotted catshark (Scyliorhinus canicula). However, no evidence of genetic structure was found across its northeastern Atlantic (NEA) range using traditional molecular markers. Here, fine-scale genetic differentiation was detected between the British Isles and southern Iberia using 2674 single nucleotide polymorphism loci generated using 2b-restriction site-associated DNA (2b-RAD). Geographical distance and historical demography were two major drivers shaping the distribution of genetic diversity of S. canicula along the NEA. Significant positive spatial autocorrelation of allelic frequencies was detected, with genetic differentiation generally increasing with geographical distance. However, marked genetic divergence of the Celtic Sea and South Portugal collections from their closest neighbours resulted in geographically constrained genetic breaks south of the British Isles and off southwestern Iberia. Historical demographic reconstruction of population pairs across these genetic breaks suggested a scenario of historical isolation before secondary contact, probably related to distinct northern and southern glacial refugia. These results provide new insights into the population structure of S. canicula along the NEA and serve as a reference for benthic elasmobranchs with similar distribution ranges.

DOI

doi: 10.1093/biolinnean/bly185

Keywords

catsharks, genetic breaks, glacial refugia, isolation by distance, local populations

bly185_suppl_supplementary_figures.pdf (233 kB)
Supplementary figures

bly185_suppl_supplementary_tables.docx (55 kB)
Supplementary Tables

bly185_suppl_supplementary_information-1.docx (28 kB)
Supplementary information 1

bly185_suppl_supplementary_information-3.zip (1 kB)
Supplementary information 2

bly185_suppl_supplementary_information-2.txt (988 kB)
Supplementary information 3

Included in

Genomics Commons

Share

COinS