50 resultados para historical biogeography
em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The golden-striped salamander (Chioglossa lusitanica) is an endemic species inhabiting stream-side habitats in mountainous areas in the northwestern Iberian Peninsula. This salamandrid is listed in the IUCN Red Data Book as a threatened species. The combination of bioclimatic modeling of the species distribution and multivariate analysis of genetic and phenotypic data strengthens previous hypotheses concerning the historical biogeography of C. lusitanica: the Pleistocene subdivision of the species' range and a process of postglacial recolonization. Discrepancies between bioclimatic modeling predictions and the present-day distribution suggest that the species may still be expanding its range northwards. We propose the identification of two distinct units for the conservation of the species and suggest that this information should be taken into account in defining key areas for conservation in the Iberian Peninsula.
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The family Callichthyidae, divided into the subfamilies Corydoradinae and Callichthyinae, contains more than 200 species of armoured catfishes distributed throughout the Neotropics, as well as fossil species dating from the Palaeocene. Both subfamilies are very widely distributed throughout the continent, with some species ranges extending across multiple hypothesized biogeographical barriers. Species with such vast geographical ranges could be made up of multiple cryptic populations that are genetically distinct and have diverged over time. Although relationships among Callichthyinae genera have been thoroughly investigated, the historical biogeography of the Callichthyinae and the presence of species complexes have yet to be examined. Furthermore, there is a lack of fossil-calibrated molecular phylogenies providing a time frame for the evolution of the Callichthyinae. Here, we present a novel molecular data set for all Callichthyinae genera composed of partial sequences of mitochondrial and nuclear markers. These data were used to construct a fossil-calibrated tree for the Callichthyinae and to reconstruct patterns of spatiotemporal evolution. All phylogenetic analyses [Bayesian, maximum likelihood and maximum parsimony (MP)] resulted in a single fully resolved and well-supported hypothesis for the Callichthyinae, where Dianema is the sister group of all the remaining genera. Results suggest that the ancestry of most Callichthyinae genera originated in the Amazonas basin, with a number of subsequent ancestral dispersal events between adjacent basins. High divergences in sequences and time were observed for several samples of Hoplosternum littorale, Megalechis picta and Callichthys callichthys, suggesting that these species may contain cryptic diversity. The results highlight the need for a taxonomic revision of species complexes within the Callichthyinae, which may reveal more diversity within this relatively species-poor lineage. © 2013 Blackwell Verlag GmbH.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Aim The aim of this study was to understand the biogeography of Brachygastra. As the spatial component of evolution is of fundamental importance to understanding the processes shaping the evolution of taxa, the known geological history of the Neotropical region was used together with the current phylogeny and distribution of species to investigate questions concerning the biogeography of Brachygastra: the ancestral ranges of Brachygastra species; their areal relationships and their congruence with previously published hypotheses; the possible associated vicariance events and the influence of land bridges between North and South America, and the split between the Amazon and Atlantic forests. Location Neotropical region, from Mexico to central Argentina and southern USA. Methods Statistical dispersal–vicariance analysis (S-DIVA) was used to reconstruct the possible ancestral ranges of Brachygastra species based on their phylogeny (divided into three groups, lecheguana, scuttelaris and smithii). A Brooks parsimony analysis (BPA) and component analysis were performed to reconstruct the areal relationships of these species within the Neotropics. Results S-DIVA suggested a widespread, South American ancestral region for Brachygastra. The ancestral B. azteca probably reached the Nearctic before a posterior vicariance event separated it from the species groups ((lecheguana (scutellaris + smithii))), that stayed in the Atlantic forest. The ancestral (scutellaris + smithii groups) possibly reached the Amazon by dispersal, and the subsequent vicariance event splitting the Atlantic forest and Amazon separated the groups into scutellaris in the Atlantic forest and smithii in the Amazon. BPA and component analyses suggested that the Nearctic was a sister area to other regions, the Andes and Mesoamerica was a sister area to the Neotropical regions and the Amazon was closely related to the Atlantic forest. Main conclusions The phylogeny and distribution of Brachygastra suggest the influence of a land bridge between the Northern and Southern Hemispheres affecting the cladogenesis of B. azteca and the importance of the formation of the two blocks of forests in South America to the cladogenesis of the main groups of Brachygastra. Future comparisons between the distribution patterns of other taxa should enable a more precise identification of the possible events and outcomes, adding robustness to the hypothesized areal relationships.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)