Marked phylogeographic structure of Gentoo penguin reveals an ongoing diversification process along the Southern Ocean

• Published in: Molecular Phylogenetics and Evolution
• Main Authors: Vianna, Juliana A., Noll, Daly, Dantas, Gisele P.M., Petry, Maria Virginia, Barbosa, Andrés, González-Acuña, Daniel, Le Bohec, Céline, Bonadonna, Francesco, Poulin, Elie
• Other Authors: Pontificia Universidad Católica de Chile (UC), Pontifícia Universidade Católica de Minas Gerais (PUC Minas), Universidade do Vale do Rio dos Sinos (UNISINOS), Departamento de Ecología Evolutiva (Museo Nacional de Ciencias Naturales), Museo Nacional de Ciencias Naturales (MNCN), Universidad de Concepción Chile, Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centre Scientifique de Monaco (CSM), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD France-Sud ), Instituto de Ecología y Biodiversidad (IEB)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: Climate change; Demographic history; Polar region; Population structure; Seabirds; [SDE]Environmental Sciences; Antarctic; Antarctic Peninsula; Kerguelen; Kerguelen Islands; Kya; South Shetland Islands; Southern Ocean; The Antarctic; Antarc*; Crozet Islands; Gentoo penguin; Pygoscelis papua
• Online Access: https://hal.archives-ouvertes.fr/hal-01531456; https://doi.org/10.1016/j.ympev.2016.12.003

International audience Two main hypotheses have been debated about the biogeography of the Southern Ocean: (1) theAntarctic Polar Front (APF), acting as a barrier between Antarctic and sub-Antarctic provinces, and (2)the Antarctic Circumpolar Current (ACC), promoting gene flow among sub-Antarctic areas. The Gentoopenguin is distributed throughout these two provinces, separated by the APF. We analyzed mtDNA(HVR1) and 12 microsatellite loci of 264 Gentoo penguins, Pygoscelis papua, from 12 colonies spanningfrom the Western Antarctic Peninsula and the South Shetland Islands (WAP) to the sub-AntarcticIslands (SAI). While low genetic structure was detected among WAP colonies (mtDNA UST = 0.037–0.133; microsatellite FST = 0.009–0.063), high differentiation was found between all SAI and WAP populations(mtDNA UST = 0.678–0.930; microsatellite FST = 0.110–0.290). These results suggest that contemporarydispersal around the Southern Ocean is very limited or absent. As predicted, the APF appears to bea significant biogeographical boundary for Gentoo penguin populations; however, the ACC does not promoteconnectivity in this species. Our data suggest demographic expansion in the WAP during the lastglacial maximum (LGM, about 20 kya), but stability in SAI. Phylogenetic analyses showed a deep divergencebetween populations from the WAP and those from the SAI. Therefore, taxonomy should be furtherrevised. The Crozet Islands resulted as a basal clade (3.57 Mya), followed by the Kerguelen Islands(2.32 Mya) as well as a more recent divergence between the Falkland/Malvinas Islands and the WAP(1.27 Mya). Historical isolation, local adaptation, and past climate scenarios of those EvolutionarilySignificant Units may have led to different potentials to respond to climate changes.