Extinction and recolonization of maritime <scp>A</scp>ntarctica in the limpet <scp>N</scp>acella concinna (Strebel, 1908) during the last glacial cycle: toward a model of Quaternary biogeography in shallow <scp>A</scp>ntarctic invertebrates

• Published in: Molecular Ecology
• Main Authors: González‐Wevar, C. A., Saucède, T., Morley, S. A., Chown, S. L., Poulin, E.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2013
• Subjects: Genetics; Ecology, Evolution, Behavior and Systematics; Antarc*; Antarctica
• Online Access: http://dx.doi.org/10.1111/mec.12465; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fmec.12465; https://onlinelibrary.wiley.com/doi/pdf/10.1111/mec.12465

Abstract Quaternary glaciations in A ntarctica drastically modified geographical ranges and population sizes of marine benthic invertebrates and thus affected the amount and distribution of intraspecific genetic variation. Here, we present new genetic information in the A ntarctic limpet N acella concinna , a dominant A ntarctic benthic species along shallow ice‐free rocky ecosystems. We examined the patterns of genetic diversity and structure in this broadcast spawner along maritime A ntarctica and from the peri‐ A ntarctic island of South Georgia. Genetic analyses showed that N . concinna represents a single panmictic unit in maritime A ntarctic. Low levels of genetic diversity characterized this population; its median‐joining haplotype network revealed a typical star‐like topology with a short genealogy and a dominant haplotype broadly distributed. As previously reported with nuclear markers, we detected significant genetic differentiation between South Georgia I sland and maritime A ntarctica populations. Higher levels of genetic diversity, a more expanded genealogy and the presence of more private haplotypes support the hypothesis of glacial persistence in this peri‐ A ntarctic island. B ayesian Skyline plot and mismatch distribution analyses recognized an older demographic history in South Georgia. Approximate Bayesian computations did not support the persistence of N . concinna along maritime Antarctica during the last glacial period, but indicated the resilience of the species in peri‐ A ntarctic refugia (South Georgia I sland). We proposed a model of Quaternary Biogeography for A ntarctic marine benthic invertebrates with shallow and narrow bathymetric ranges including (i) extinction of maritime A ntarctic populations during glacial periods; (ii) persistence of populations in peri‐ A ntarctic refugia; and (iii) recolonization of maritime A ntarctica following the deglaciation process.