title: Phylogeographic analyses of the 30 degrees S south-east Pacific biogeographic transition zone establish the occurrence of a sharp genetic discontinuity in the kelp Lessonia nigrescens: vicariance or parapatry?
abstract: Phylogeographic studies are lacking in the Southern Hemisphere, and in particular in the south-eastern Pacific. To infer the possible scenario for the debated biogeographic transition zone located at 30-33 degrees S along the Chilean coast, we investigated whether there is a concordance between the phylogeographic pattern and the biogeographic transition in the intertidal kelp Lessonia nigrescens whose distribution is continuous across this transition zone. Using a combination of four makers located in the three genomic compartments (chloroplast, mitochondria and nucleus), we showed the presence of two main divergent lineages, possibly cryptic species. There was an exact match of the phylogeographic break with the 30 degrees S biogeographic transition zone, suggesting a common origin. The combined information given by the multilocus approach and by the population analysis suggested the occurrence of a budding speciation, with a northward range expansion.
authors: UPMC Université Paris VI, UMR 7144, Equipe Evolution et Génétique des Populations Marines, LIA DIAMS, Station Biologique de Roscoff, B.P. 74, Place Georges Teissier, 29682 Roscoff, France.
authors: Florence
authors: F
authors: Tellier
authors: Andrés P
authors: AP
authors: Meynard
authors: Juan A
authors: JA
authors: Correa
authors: Sylvain
authors: S
authors: Faugeron
authors: Myriam
authors: M
authors: Valero
mesh_terms: D001483:Base Sequence; D002467:Cell Nucleus / Q000235:genetics; D048028:DNA, Algal / Q000235:genetics; D018742:DNA, Chloroplast / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D019143:Evolution, Molecular; D049810:Genetic Speciation; D005828:Genetics, Population; D005843:Geography; D044423:Kelp / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D010140:Pacific Ocean; D010802:Phylogeny; D018807:Polymorphism, Single-Stranded Conformational; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D048028:DNA, Algal; D018742:DNA, Chloroplast; D004272:DNA, Mitochondrial