title: Patterns of colonization, evolution and gene flow in species of the genus Patella in the Macaronesian Islands.
abstract: The study of phylogeographical patterns may contribute to a better understanding of factors affecting the dispersal of organisms in ecological and historical times. For intertidal organisms, islands are particularly suitable models allowing the test of predictions related to the efficacy of pelagic larvae dispersal. Here, we study the phylogeographical patterns and gene flow within three groups of species of the genus Patella present in the Macaronesian Islands that have been previously shown to be monophyletic. The genetic variability of around 600 bp of the mitochondrial gene cytochrome c oxidase subunit I was studied by single strand conformation polymorphism and/or sequencing for seven species of limpets. A total of 420 samples were analysed from the Macaronesian archipelagos, North Africa, and Atlantic and Mediterranean shores of the Iberian Peninsula. No clear geographical pattern or temporal congruence was found between the three groups of species, pointing to independent histories and colonization events. However, for the three groups, the split between the Macaronesian and the mainland forms most probably occurred before 3.9 million years ago, predating the establishment of the current circulation patterns. The presence of pelagic larvae in these species is shown to be insufficient to ensure gene flow between continental and Macaronesian populations and between the Macaronesian archipelagos. In the endangered Azorean populations of Patella candei, there is restricted gene flow to Flores and Graciosa.
authors.affiliation: CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, 4485-661 Vairão, Portugal. xanasapinto@gmail.com
authors.forename: Alexandra
authors.initials: A
authors.lastname: Sá-Pinto
authors.forename: Madalena
authors.initials: M
authors.lastname: Branco
authors.forename: Diogo
authors.initials: D
authors.lastname: Sayanda
authors.forename: Paulo
authors.initials: P
authors.lastname: Alexandrino
mesh_terms: D000354:Africa, Western; D000818:Animals; D001394:Azores; D003576:Electron Transport Complex IV / Q000235:genetics; D019143:Evolution, Molecular; D049851:Gastropoda / Q000145:classification / Q000235:genetics* / Q000254:growth & development; D051456:Gene Flow; D005843:Geography; D016013:Likelihood Functions; D008969:Molecular Sequence Data; D010802:Phylogeny; D011174:Portugal; D017422:Sequence Analysis, DNA; D013030:Spain; D013045:Species Specificity
chemical_list: D003576:Electron Transport Complex IV