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Allan J Baker - One of the best experts on this subject based on the ideXlab platform.

  • mitochondrial and nuclear dna sequences support a cretaceous origin of Columbiformes and a dispersal driven radiation in the paleogene
    Systematic Biology, 2007
    Co-Authors: Sergio L Pereira, Kevin P Johnson, Dale H Clayton, Allan J Baker
    Abstract:

    Phylogenetic relationships among genera of pigeons and doves (Aves, Columbiformes) have not been fully re- solved because of limited sampling of taxa and characters in previous studies. We therefore sequenced multiple nuclear and mitochondrial DNA genes totaling over 9000 bp from 33 of 41 genera plus 8 outgroup taxa, and, together with sequences from 5 other pigeon genera retrieved from GenBank, recovered a strong phylogenetic hypothesis for the Columbiformes. Three major clades were recovered with the combined data set, comprising the basally branching New World pigeons and allies (clade A) that are sister to Neotropical ground doves (clade B), and the Afro-Eurasian and Australasian taxa (clade C). None of these clades supports the monophyly of current families and subfamilies. The extinct, flightless dodo and soli- taires (Raphidae) were embedded within pigeons and doves (Columbidae) in clade C, and monophyly of the subfamily Columbinae was refuted because the remaining subfamilies were nested within it. Divergence times estimated using a Bayesian framework suggest that Columbiformes diverged from outgroups such as Apodiformes and Caprimulgiformes in the Cretaceous before the mass extinction that marks the end of this period. Bayesian and maximum likelihood inferences of ancestral areas, accounting for phylogenetic uncertainty and divergence times, respectively, favor an ancient origin of Columbiformes in the Neotropical portion of what was then Gondwana. The radiation of modern genera of Columbiformes started in the Early Eocene to the Middle Miocene, as previously estimated for other avian groups such as ratites, tinamous, galliform birds, penguins, shorebirds, parrots, passerine birds, and toucans. Multiple dispersals of more derived Columb- iformes between Australasian and Afro-Eurasian regions are required to explain current distributions. (Columbiformes; dispersal; divergence times; doves; fossil; K/T boundary; molecular phylogeny; pigeons.)

Maciej Skoracki - One of the best experts on this subject based on the ideXlab platform.

Dale H Clayton - One of the best experts on this subject based on the ideXlab platform.

  • There and back again: Switching between host orders by avian body lice (Ischnocera: Goniodidae)
    Biological Journal of the Linnean Society, 2011
    Co-Authors: Kevin P Johnson, Jason D. Weckstein, Mathys J. Meyer, Dale H Clayton
    Abstract:

    Studies of major switches by parasites between highly divergent host lineages are important for understanding new opportunities for parasite diversification. One such major host switch is inferred for avian feather lice (Ischnocera) in the family Goniodidae, which parasitize two distantly-related groups of birds: Galliformes (pheasants, quail, partridges, etc.) and Columbiformes (pigeons and doves). Although there have been several cophylogenetic studies of lice at the species level, few studies have focused on such broad evolutionary patterns and major host-switching events. Using a phylogeny based on DNA sequences for goniodid feather lice, we investigated the direction of this major host switch. Unexpectedly, we found that goniodid feather lice have switched host orders, not just once, but twice. A primary host switch occurred from Galliformes to Columbiformes, leading to a large radiation of columbiform body lice. Subsequently, there was also a host switch from Columbiformes back to Galliformes, specifically to megapodes in the Papua–Australasian region. The results of the present study further reveal that, although morphologically diagnosable lineages are supported by molecular data, many of the existing genera are not monophyletic and a revision of generic limits is needed. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102, 614–625.

  • mitochondrial and nuclear dna sequences support a cretaceous origin of Columbiformes and a dispersal driven radiation in the paleogene
    Systematic Biology, 2007
    Co-Authors: Sergio L Pereira, Kevin P Johnson, Dale H Clayton, Allan J Baker
    Abstract:

    Phylogenetic relationships among genera of pigeons and doves (Aves, Columbiformes) have not been fully re- solved because of limited sampling of taxa and characters in previous studies. We therefore sequenced multiple nuclear and mitochondrial DNA genes totaling over 9000 bp from 33 of 41 genera plus 8 outgroup taxa, and, together with sequences from 5 other pigeon genera retrieved from GenBank, recovered a strong phylogenetic hypothesis for the Columbiformes. Three major clades were recovered with the combined data set, comprising the basally branching New World pigeons and allies (clade A) that are sister to Neotropical ground doves (clade B), and the Afro-Eurasian and Australasian taxa (clade C). None of these clades supports the monophyly of current families and subfamilies. The extinct, flightless dodo and soli- taires (Raphidae) were embedded within pigeons and doves (Columbidae) in clade C, and monophyly of the subfamily Columbinae was refuted because the remaining subfamilies were nested within it. Divergence times estimated using a Bayesian framework suggest that Columbiformes diverged from outgroups such as Apodiformes and Caprimulgiformes in the Cretaceous before the mass extinction that marks the end of this period. Bayesian and maximum likelihood inferences of ancestral areas, accounting for phylogenetic uncertainty and divergence times, respectively, favor an ancient origin of Columbiformes in the Neotropical portion of what was then Gondwana. The radiation of modern genera of Columbiformes started in the Early Eocene to the Middle Miocene, as previously estimated for other avian groups such as ratites, tinamous, galliform birds, penguins, shorebirds, parrots, passerine birds, and toucans. Multiple dispersals of more derived Columb- iformes between Australasian and Afro-Eurasian regions are required to explain current distributions. (Columbiformes; dispersal; divergence times; doves; fossil; K/T boundary; molecular phylogeny; pigeons.)

Kevin P Johnson - One of the best experts on this subject based on the ideXlab platform.

  • There and back again: Switching between host orders by avian body lice (Ischnocera: Goniodidae)
    Biological Journal of the Linnean Society, 2011
    Co-Authors: Kevin P Johnson, Jason D. Weckstein, Mathys J. Meyer, Dale H Clayton
    Abstract:

    Studies of major switches by parasites between highly divergent host lineages are important for understanding new opportunities for parasite diversification. One such major host switch is inferred for avian feather lice (Ischnocera) in the family Goniodidae, which parasitize two distantly-related groups of birds: Galliformes (pheasants, quail, partridges, etc.) and Columbiformes (pigeons and doves). Although there have been several cophylogenetic studies of lice at the species level, few studies have focused on such broad evolutionary patterns and major host-switching events. Using a phylogeny based on DNA sequences for goniodid feather lice, we investigated the direction of this major host switch. Unexpectedly, we found that goniodid feather lice have switched host orders, not just once, but twice. A primary host switch occurred from Galliformes to Columbiformes, leading to a large radiation of columbiform body lice. Subsequently, there was also a host switch from Columbiformes back to Galliformes, specifically to megapodes in the Papua–Australasian region. The results of the present study further reveal that, although morphologically diagnosable lineages are supported by molecular data, many of the existing genera are not monophyletic and a revision of generic limits is needed. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102, 614–625.

  • mitochondrial and nuclear dna sequences support a cretaceous origin of Columbiformes and a dispersal driven radiation in the paleogene
    Systematic Biology, 2007
    Co-Authors: Sergio L Pereira, Kevin P Johnson, Dale H Clayton, Allan J Baker
    Abstract:

    Phylogenetic relationships among genera of pigeons and doves (Aves, Columbiformes) have not been fully re- solved because of limited sampling of taxa and characters in previous studies. We therefore sequenced multiple nuclear and mitochondrial DNA genes totaling over 9000 bp from 33 of 41 genera plus 8 outgroup taxa, and, together with sequences from 5 other pigeon genera retrieved from GenBank, recovered a strong phylogenetic hypothesis for the Columbiformes. Three major clades were recovered with the combined data set, comprising the basally branching New World pigeons and allies (clade A) that are sister to Neotropical ground doves (clade B), and the Afro-Eurasian and Australasian taxa (clade C). None of these clades supports the monophyly of current families and subfamilies. The extinct, flightless dodo and soli- taires (Raphidae) were embedded within pigeons and doves (Columbidae) in clade C, and monophyly of the subfamily Columbinae was refuted because the remaining subfamilies were nested within it. Divergence times estimated using a Bayesian framework suggest that Columbiformes diverged from outgroups such as Apodiformes and Caprimulgiformes in the Cretaceous before the mass extinction that marks the end of this period. Bayesian and maximum likelihood inferences of ancestral areas, accounting for phylogenetic uncertainty and divergence times, respectively, favor an ancient origin of Columbiformes in the Neotropical portion of what was then Gondwana. The radiation of modern genera of Columbiformes started in the Early Eocene to the Middle Miocene, as previously estimated for other avian groups such as ratites, tinamous, galliform birds, penguins, shorebirds, parrots, passerine birds, and toucans. Multiple dispersals of more derived Columb- iformes between Australasian and Afro-Eurasian regions are required to explain current distributions. (Columbiformes; dispersal; divergence times; doves; fossil; K/T boundary; molecular phylogeny; pigeons.)

  • Deletion Bias in Avian Introns over Evolutionary Timescales
    Molecular Biology and Evolution, 2004
    Co-Authors: Kevin P Johnson
    Abstract:

    The role that introns play in the function and evolution of nuclear genomes is not fully understood. Recent models of intron evolution suggest that selection and drift may interact to maintain introns in multicellular organisms. In addition, deletion mutations are more likely to become fixed than insertion mutations. Examination of indel substitutions over macroevolutionary timescales in pigeons and doves (Aves: Columbiformes) reveals that deletion substitutions outnumber insertion substitutions by over six times. The length of indel events is variable.

Bruno Pereira Berto - One of the best experts on this subject based on the ideXlab platform.

  • eimeria ferreirai n sp chromista miozoa eimeriidae from doves leptotila spp Columbiformes columbidae from brazil
    Zootaxa, 2020
    Co-Authors: Mariana De Souza Oliveira, Jhon Lennon Genovezoliveira, Carlos Nei Ortuzarferreira, Carla Maronezi, Sergio Thodefilho, Sergian Vianna Cardozo, Aguida Aparecida De Oliveira, Viviane Moreira De Lima, Bruno Pereira Berto
    Abstract:

    The doves and pigeons constitute a taxonomic group (Columbiformes: Columbidae) of granivorous and frugivorous birds with a worldwide distribution. The current work aims to describe morphologically and molecularly a new protozoan from white-tipped doves Leptotila verreauxi Bonaparte, 1855 and grey-fronted doves Leptotila rufaxilla (Richard Bernard, 1792) in Southeastern Brazil. Eimeria ferreirai n. sp. has oocysts that are sub-spherical to ellipsoidal, 21.4 × 18.8 μm, with smooth, bilayered wall, ~1.6 μm thick. Micropyle present. Oocyst residuum absent, but one to two polar granules are present. Sporocysts are elongate ovoidal to boomerang-shaped, 13.4 × 6.9 μm. Stieda body triangular to lozengal. Sporocyst residuum is composed of granules of different sizes. Sporozoites are vermiform with refractile body and nucleus. Sequencing of the mitochondrial cytochrome c oxidase subunit 1 (COI) gene and the subsequent phylogenetic molecular comparisons supported the description of the new species, since the maximum similarity was 90-95% with eimeriid species of Columbiformes, Anseriformes, Galliformes and Passeriformes. Thus, this is the first coccidian species reported from Leptotila spp. and the twentieth description of an eimerian from Columbiformes in the World.

  • Coccidia of Columbiformes: a taxonomic review of its Eimeriidae species and Eimeria columbinae n. sp. from Columbina talpacoti (Temminck, 1809) from Brazil.
    Parasitology Research, 2019
    Co-Authors: Carlos Nei Ortúzar-ferreira, Mariana De Souza Oliveira, Sergian Vianna Cardozo, Aguida Aparecida De Oliveira, Viviane Moreira De Lima, Jhon Lennon Genovez-oliveira, Heider Alves Franco, Sergio Thode-filho, Ildemar Ferreira, Bruno Pereira Berto
    Abstract:

    Coccidia (Chromista: Miozoa: Eimeriidae) of columbiform birds (Aves: Columbiformes) have been described since the end of the nineteenth century; however, some of these descriptions were poorly detailed or inconclusive. In this sense, the current work makes a detailed taxonomic revision reconsidering and organizing 18 Eimeria spp. and two Isospora spp. previously described or reported of Columbiformes. Along with this, a new species of Eimeria is morphologically and molecularly identified by the mitochondrial cytochrome c oxidase subunit 1 (COI) gene and by the 18S small subunit ribosomal RNA (18S) gene from the ruddy ground-dove Columbina talpacoti (Temminck, 1809) in the Medio Paraiba region of the State of Rio de Janeiro, southeastern Brazil. Eimeria columbinae n. sp. has subspheroidal oocysts, 14.7 × 13.2 μm, with smooth, bi-layered wall, ~ 1.1 μm and length/width ratio of 1.1. Micropyle and oocyst residuum are present, but polar granule is absent. Sporocysts are ellipsoidal to slightly asymmetrical, 9.0 × 5.1 μm, with both Stieda and sub-Stieda bodies. Sporocyst residuum present and sporozoites with refractile body and nucleus. This is the 19th description of an eimerian from Columbiformes in the World, and the second to have a molecular identification of the COI and 18S genes.