title: The evolutionary diversification of the Centropagidae (Crustacea, Calanoida): A history of habitat shifts.
abstract: The copepod family Centropagidae is widely distributed and occurs in marine, estuarine, freshwater, and inland saline settings. Molecular phylogenies based upon the 16S and 28S genes demonstrate a complex biogeographic history, involving at least five independent invasions of continental waters from the sea. The first colonization was ancient, likely into part of Gondwanaland, and resulted in an inland radiation in southern genera via both vicariance and subsequent habitat shifting among different types of continental waters. Species occupying saline lakes are nested within freshwater clades, indicating invasion of these habitats via fresh waters rather than directly from the ocean or from epicontinental seas. In contrast with the great southern clade, all of the remaining continental invasions are northern, species poor, and quite recent, perhaps even Pleistocene. Long-lived evolutionary euryhalinity, a high propensity for inland invasion, continental vicariance, and in situ radiation within single continents have all played major roles in the diversification of the centropagids.
authors.affiliation: Biodiversity Institute of Ontario, Department of Integrative Biology, 579 Gordon St., University of Guelph, Guelph, ON, Canada N1G 2W1. sadamowi@uoguelph.ca
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Adamowicz
authors.forename: Silvina
authors.initials: S
authors.lastname: Menu-Marque
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Halse
authors.forename: Janet C
authors.initials: JC
authors.lastname: Topan
authors.forename: Tyler S
authors.initials: TS
authors.lastname: Zemlak
authors.forename: Paul D N
authors.initials: PD
authors.lastname: Hebert
authors.forename: Jonathan D S
authors.initials: JD
authors.lastname: Witt
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D033342:Copepoda / Q000145:classification / Q000235:genetics*; D017753:Ecosystem; D019143:Evolution, Molecular; D014644:Genetic Variation; D005843:Geography; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012339:RNA, Ribosomal, 28S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D012336:RNA, Ribosomal, 16S; D012339:RNA, Ribosomal, 28S