title: Understanding the mechanisms of antitropical divergence in the seabird White-faced Storm-petrel (Procellariiformes: Pelagodroma marina) using a multilocus approach.
abstract: Analytical methods that apply coalescent theory to multilocus data have improved inferences of demographic parameters that are critical to understanding population divergence and speciation. In particular, at the early stages of speciation, it is important to implement models that accommodate conflicting gene trees, and benefit from the presence of shared polymorphisms. Here, we employ eleven nuclear loci and the mitochondrial control region to investigate the phylogeography and historical demography of the pelagic seabird White-faced Storm-petrel (Pelagodroma marina) by sampling subspecies across its antitropical distribution. Groups are all highly differentiated: global mitochondrial ΦST = 0.89 (P < 0.01) and global nuclear ΦST varies between 0.22 and 0.83 (all P < 0.01). The complete lineage sorting of the mitochondrial locus between hemispheres is corroborated by approximately half of the nuclear genealogies, suggesting a long-term antitropical divergence in isolation. Coalescent-based estimates of demographic parameters suggest that hemispheric divergence of P. marina occurred approximately 840 000 ya (95% HPD 582 000-1 170 000), in the absence of gene flow, and divergence within the Southern Hemisphere occurred 190 000 ya (95% HPD 96 000-600 000), both probably associated with the profound palaeo-oceanographic changes of the Pleistocene. A fledgling sampled in St Helena (tropical South Atlantic) suggests recent colonization from the Northern Hemisphere. Despite the great potential for long-distance dispersal, P. marina antitropical groups have been evolving as independent, allopatric lineages, and divergence is probably maintained by philopatry coupled with asynchronous reproductive phenology and local adaptation.
authors.affiliation: Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.
authors.forename: Mónica C
authors.initials: MC
authors.lastname: Silva
authors.affiliation: Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Penryn, TR10 9EZ, UK.|Marine and Environmental Sciences Centre, ISPA-Instituto Universitário, 1149-041, Lisboa, Portugal.
authors.forename: Rafael
authors.initials: R
authors.lastname: Matias
authors.affiliation: Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, 7701, South Africa.|Seabird Conservation Program, BirdLife South Africa, PO Box 7119, Roggebaai, 8012, South Africa.
authors.forename: Ross M
authors.initials: RM
authors.lastname: Wanless
authors.affiliation: Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, 7701, South Africa.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Ryan
authors.affiliation: Eco-Vista: Photography & Research Ltd, PO Box 157, Bay View, Napier, 4149, New Zealand.
authors.forename: Brent M
authors.initials: BM
authors.lastname: Stephenson
authors.affiliation: RSPB Centre for Conservation Science, Royal Society for the Protection of Birds, The Lodge, Sandy, Beds, SG19 2DL, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Bolton
authors.affiliation: CIBIO, Universidade do Porto, Campus Agrário Vairão, 4485-661, Vairão, Portugal.
authors.forename: Nuno
authors.initials: N
authors.lastname: Ferrand
authors.affiliation: Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.
authors.forename: M Manuela
authors.identifier: http://orcid.org/0000-0003-3288-1693
authors.initials: MM
authors.lastname: Coelho
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D001717:Birds / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D019143:Evolution, Molecular; D014644:Genetic Variation; D005828:Genetics, Population; D008969:Molecular Sequence Data; D010802:Phylogeny; D058974:Phylogeography; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial
keywords: Pelagodroma; Procellariiformes; anonymous nuclear markers; antitropical divergence; coalescence; gene flow