title: Temporal and spatial genetic differentiation in the crab Liocarcinus depurator across the Atlantic-Mediterranean transition.
abstract: Spatial genetic studies often require sampling broadly separated areas, difficult to access simultaneously. Although comparing localities surveyed at different time periods might result in spurious genetic differentiation, there is a general believe on the stability of genetic structure through time, particularly if sampled localities are isolated or very distant. By analysing spatial and temporal genetic differentiation of the portunid crab Liocarcinus depurator we assessed the contribution of historical and contemporary processes on population connectivity patterns across three main oceanographic discontinuities along the Atlantic-Mediterranean transition: Gibraltar Strait, Almeria-Oran Front and Ibiza Channel. A partial fragment of the cytochrome oxidase I gene was sequenced in 366 individuals collected from localities at both sides of each discontinuity during three time periods. Although localities showed genetic fluctuations through time, a significant gradient was detected along the coast for all sampling periods. Significant inter-annual differences identified within the Alicante area, north of the Almeria-Oran Front, were associated with shifts in the relative contribution of Atlantic and Mediterranean water masses. The persistence of a clinal pattern in the Atlantic-Mediterranean transition area together with local fluctuations suggests a complex balance of dispersal and selection.
authors.affiliation: Dept. Genètica, Microbiologia i Estadística and IRBio, University of Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Pascual
authors.affiliation: Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la Cala Sant Francesc 14, 17300 Blanes, Spain.
authors.forename: Ferran
authors.initials: F
authors.lastname: Palero
authors.affiliation: University of Quindio (Group of Evolution, Ecology and Conservation, EECO), Armenia, Quindío (Colombia).
authors.forename: Víctor Hugo
authors.initials: VH
authors.lastname: García-Merchán
authors.affiliation: Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la Cala Sant Francesc 14, 17300 Blanes, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Macpherson
authors.affiliation: Dept. Genètica, Microbiologia i Estadística and IRBio, University of Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain.
authors.forename: Aymée
authors.initials: A
authors.lastname: Robainas-Barcia
authors.affiliation: Dept. Genètica, Microbiologia i Estadística and IRBio, University of Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain.
authors.forename: Francesc
authors.initials: F
authors.lastname: Mestres
authors.affiliation: Dept. Genètica, Microbiologia i Estadística and IRBio, University of Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain.
authors.forename: Tania
authors.initials: T
authors.lastname: Roda
authors.affiliation: Institut de Ciències del Mar (ICM-CSIC), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Catalonia, Spain.
authors.forename: Pere
authors.initials: P
authors.lastname: Abelló
mesh_terms: D000818:Animals; D003386:Brachyura / Q000235:genetics*; D051456:Gene Flow; D040961:Genetic Drift; D049810:Genetic Speciation; D005828:Genetics, Population; D005843:Geography; D018895:Microsatellite Repeats / Q000235:genetics; D010802:Phylogeny