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1.
Pap. avulsos Zool. ; 60: e20206050, Sept. 29, 2020. ilus, mapas
Artigo em Inglês | VETINDEX | ID: vti-33422

RESUMO

The genus Leptodon encompasses two Neotropical raptor species. The more widely-distributed Gray-headed Kite (Leptodon cayanensis) occurs in a vast area of Neotropical region, while the White-collared Kite (Leptodon forbesi) is endemic of the Atlantic Forest of northeastern Brazil, but there are some questions about the extent of its geographic distribution and about its sympatry with its congener. Here we present a review of the geographic distribution and the diagnoses of L. forbesi, correcting recent records based on misidentifications. We also clarify the main features of juvenile and subadult plumage of Leptodon raptors and describe new phases of juvenile plumage.(AU)


Assuntos
Animais , Papagaios/anatomia & histologia , Papagaios/classificação , Distribuição Animal , Falcões/anatomia & histologia , Falcões/classificação , Espécies em Perigo de Extinção , Brasil
2.
Pap. avulsos zool ; 60: e20206050, Feb. 14, 2020. ilus, map
Artigo em Inglês | VETINDEX | ID: biblio-1487267

RESUMO

The genus Leptodon encompasses two Neotropical raptor species. The more widely-distributed Gray-headed Kite (Leptodon cayanensis) occurs in a vast area of Neotropical region, while the White-collared Kite (Leptodon forbesi) is endemic of the Atlantic Forest of northeastern Brazil, but there are some questions about the extent of its geographic distribution and about its sympatry with its congener. Here we present a review of the geographic distribution and the diagnoses of L. forbesi, correcting recent records based on misidentifications. We also clarify the main features of juvenile and subadult plumage of Leptodon raptors and describe new phases of juvenile plumage.


Assuntos
Animais , Distribuição Animal , Falcões/anatomia & histologia , Falcões/classificação , Papagaios/anatomia & histologia , Papagaios/classificação , Brasil , Espécies em Perigo de Extinção
3.
J Parasitol ; 95(6): 1372-82, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19655998

RESUMO

In an evolutionary context, parasites tend to be morphologically conservative relative to their hosts. However, the rate of neutral molecular evolution across many parasite lineages is faster than in their hosts. Although this relationship is apparent at the macroevolutionary scale, insight into the processes underpinning it may be gained through investigations at the microevolutionary scale. Birds and their ectoparasitic lice have served as important natural experiments in co-evolution. Here, we compared mitochondrial and morphological divergence in 2 recently diverged avian host lineages and their parasites. Gálapagos hawks (Buteo galapagoensis) are phenotypically divergent from their closest mainland relatives, the Swainson's hawk (Buteo swainsoni). Both species are host to a feather louse species of Craspedorrhynchus (Insecta: Phthiraptera: Ischnocera, Philopteridae). We sequenced the 5' end of the mitochondrial gene cytochrome oxidase c subunit I (COI) from a set of hawks and lice. Although this fragment allowed unambiguous identification of host and parasite lineages on the islands and the mainland, only a single variable site was present in the 2 hosts, but 2 major Craspedorrhynchus clades divergent by ~10% were recovered that sorted perfectly with host species. We found significant population genetic structure within the Galápagos Craspedorrhynchus lineage. While the host species are highly differentiated phenotypically, the 2 Craspedorrhynchus louse lineages are phenotypically overlapping, although subtle but significant morphological differences exist.


Assuntos
Doenças das Aves/parasitologia , Falcões/classificação , Falcões/parasitologia , Infestações por Piolhos/veterinária , Ftirápteros/classificação , Animais , Equador , Feminino , Variação Genética , Falcões/anatomia & histologia , Falcões/genética , Infestações por Piolhos/parasitologia , Masculino , América do Norte , Ftirápteros/anatomia & histologia , Ftirápteros/genética , Filogenia , Análise de Componente Principal , América do Sul
4.
Mol Phylogenet Evol ; 53(3): 703-15, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19635577

RESUMO

Buteonine hawks represent one of the most diverse groups in the Accipitridae, with 58 species distributed in a variety of habitats on almost all continents. Variations in migratory behavior, remarkable dispersal capability, and unusual diversity in Central and South America make buteonine hawks an excellent model for studies in avian evolution. To evaluate the history of their global radiation, we used an integrative approach that coupled estimation of the phylogeny using a large sequence database (based on 6411 bp of mitochondrial markers and one nuclear intron from 54 species), divergence time estimates, and ancestral state reconstructions. Our findings suggest that Neotropical buteonines resulted from a long evolutionary process that began in the Miocene and extended to the Pleistocene. Colonization of the Nearctic, and eventually the Old World, occurred from South America, promoted by the evolution of seasonal movements and development of land bridges. Migratory behavior evolved several times and may have contributed not only to colonization of the Holarctic, but also derivation of insular species. In the Neotropics, diversification of the buteonines included four disjunction events across the Andes. Adaptation of monophyletic taxa to wet environments occurred more than once, and some relationships indicate an evolutionary connection among mangroves, coastal and várzea environments. On the other hand, groups occupying the same biome, forest, or open vegetation habitats are not monophyletic. Refuges or sea-level changes or a combination of both was responsible for recent speciation in Amazonian taxa. In view of the lack of concordance between phylogeny and classification, we propose numerous taxonomic changes.


Assuntos
Migração Animal , Evolução Molecular , Falcões/genética , Filogenia , Animais , Teorema de Bayes , Núcleo Celular/genética , América Central , DNA Mitocondrial/genética , Ecossistema , Falcões/classificação , Funções Verossimilhança , Modelos Genéticos , Conformação de Ácido Nucleico , Alinhamento de Sequência , Análise de Sequência de DNA , América do Sul
5.
BMC Evol Biol ; 6: 10, 2006 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-16464261

RESUMO

BACKGROUND: The family Accipitridae (hawks, eagles and Old World vultures) represents a large radiation of predatory birds with an almost global distribution, although most species of this family occur in the Neotropics. Despite great morphological and ecological diversity, the evolutionary relationships in the family have been poorly explored at all taxonomic levels. Using sequences from four mitochondrial genes (12S, ATP8, ATP6, and ND6), we reconstructed the phylogeny of the Neotropical forest hawk genus Leucopternis and most of the allied genera of Neotropical buteonines. Our goals were to infer the evolutionary relationships among species of Leucopternis, estimate their relationships to other buteonine genera, evaluate the phylogenetic significance of the white and black plumage patterns common to most Leucopternis species, and assess general patterns of diversification of the group with respect to species' affiliations with Neotropical regions and habitats. RESULTS: Our molecular phylogeny for the genus Leucopternis and its allies disagrees sharply with traditional taxonomic arrangements for the group, and we present new hypotheses of relationships for a number of species. The mtDNA phylogenetic trees derived from analysis of the combined data posit a polyphyletic relationship among species of Leucopternis, Buteogallus and Buteo. Three highly supported clades containing Leucopternis species were recovered in our phylogenetic reconstructions. The first clade consisted of the sister pairs L. lacernulatus and Buteogallus meridionalis, and Buteogallus urubitinga and Harpyhaliaetus coronatus, in addition to L. schistaceus and L. plumbeus. The second clade included the sister pair Leucopternis albicollis and L. occidentalis as well as L. polionotus. The third lineage comprised the sister pair L. melanops and L. kuhli, in addition to L. semiplumbeus and Buteo buteo. According to our results, the white and black plumage patterns have evolved at least twice in the group. Furthermore, species found to the east and west of the Andes (cis-Andean and trans-Andean, respectively) are not reciprocally monophyletic, nor are forest and non-forest species. CONCLUSION: The polyphyly of Leucopternis, Buteogallus and Buteo establishes a lack of concordance of current Accipitridae taxonomy with the mtDNA phylogeny for the group, and points to the need for further phylogenetic analysis at all taxonomic levels in the family as also suggested by other recent analyses. Habitat shifts, as well as cis- and trans-Andean disjunctions, took place more than once during buteonine diversification in the Neotropical region. Overemphasis of the black and white plumage patterns has led to questionable conclusions regarding the relationships of Leucopternis species, and suggests more generally that plumage characters should be used with considerable caution in the taxonomic evaluation of the Accipitridae.


Assuntos
Ecossistema , Falcões/classificação , Falcões/genética , Filogenia , Animais , Plumas , Variação Genética
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