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1.
Mol Phylogenet Evol ; 131: 149-163, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30468940

RESUMO

White-nosed coatis (Nasua narica) are widely distributed throughout North, Central, and South America, but the patterns of temporal and spatial diversification that have contributed to this distribution are unknown. In addition, the biogeographic history of procyonid species in the Americas remains contentious. Using sequences from three mitochondrial loci (Cytochrome b, NAHD5 and 16S rRNA; 2201 bp) and genotypes from 11 microsatellite loci, we analyzed genetic diversity to determine phylogeographic patterns, genetic structure, divergence times, and gene flow among Nasua narica populations throughout the majority of the species' range. We also estimated the ancestral geographic range of N. narica and other procyonid species. We found a high degree of genetic structure and divergence among populations that conform to five evolutionarily significant units. The most southerly distributed population (Panama) branched off much earlier (∼3.8 million years ago) than the northern populations (<1.2 million years ago). Estimated gene flow among populations was low and mostly northwards and westwards. The phylogeographic patterns within N. narica are associated with geographic barriers and habitat shifts likely caused by Pliocene-Pleistocene climate oscillations. Significantly, our findings suggest the dispersal of N. narica was south-to-north beginning in the Pliocene, not in the opposite direction during the Pleistocene as suggested by the fossil record, and that the most recent common ancestor for coati species was most likely distributed in South or Central America six million years ago. Our study implies the possibility that the diversification of Nasua species, and other extant procyonid lineages, may have occurred in South America.


Assuntos
Variação Genética , Filogeografia , Procyonidae/classificação , Procyonidae/genética , Animais , Sequência de Bases , Teorema de Bayes , DNA Mitocondrial/genética , Fluxo Gênico , Genética Populacional , Genótipo , Repetições de Microssatélites/genética , América do Norte , Filogenia , América do Sul , Fatores de Tempo
2.
Naturwissenschaften ; 101(11): 965-74, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25228347

RESUMO

We report two fossil procyonids, Cyonasua sp. and Chapalmalania sp., from the late Pliocene of Venezuela (Vergel Member, San Gregorio Formation) and Colombia (Ware Formation), respectively. The occurrence of these pre-Holocene procyonids outside Argentina and in the north of South America provides further information about the Great American Biotic Interchange (GABI). The new specimens are recognized in the same monophyletic group as procyonids found in the southern part of the continent, the "Cyonasua group," formed by species of Cyonasua and Chapalmalania. The phylogenetic analysis that includes the two new findings support the view that procyonids dispersed from North America in two separate events (initially, previous to the first major migration wave-GABI 1-and then within the last major migration wave-GABI 4-). This involved reciprocal lineage migrations from North to South America, and included the evolution of South American endemic forms.


Assuntos
Migração Animal , Fósseis , Filogenia , Procyonidae/anatomia & histologia , Procyonidae/classificação , Animais , Colômbia , Procyonidae/fisiologia , Venezuela
3.
Rev. patol. trop ; 41(3): 253-269, jul.-set. 2012.
Artigo em Português | LILACS | ID: lil-664755

RESUMO

Os procionídeos são animais de hábitos terrestres e arbóreos, encontrados em diferentes habitats. Embora classificados como carnívoros, englobam importantes espécies onívoras que, além de serem dispersoras de sementes de frutos, exercem influência sobre o tamanho das populações de suas presas vertebradas e servem como fonte de alimento para os grandes felinos silvestres. Apesardos benefícios que os procionídeos conferem ao meio ambiente, seu contato com o ambiente urbano pode trazer riscos à saúde. Podem ser acometidos por patógenos adquiridos dos animais domésticos que vivem no entorno das Unidades de Conservação e transmiti-los ou servir de reservatório para outros animais e para o homem. Portanto, esta atualização objetivou realizar um levantamento dos estudos de prevalência, detecção e isolamento de patógenos com potencial zoonótico encontrados nas espécies de procionídeos mais amplamente distribuídas nas Américas.


Assuntos
Animais , Procyonidae/classificação , Reservatórios de Doenças , Monitoramento Epidemiológico , Zoonoses
4.
Cytogenet Genome Res ; 137(2-4): 174-93, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22889959

RESUMO

The order of Carnivora has been very well characterized with over 50 species analyzed by chromosome painting and with painting probe sets made for 9 Carnivora species. Representatives of almost all families have been studied with few exceptions (Otariidae, Odobenidae, Nandiniidae, Prionodontidae). The patterns of chromosome evolution in Carnivora are discussed here. Overall, many Carnivora species retained karyotypes that only slightly differ from the ancestral carnivore karyotype. However, there are at least 3 families in which the ancestral carnivore karyotype has been severely rearranged - Canidae, Ursidae and Mephitidae. Here we report chromosome painting of yet another Carnivora species with a highly rearranged karyotype, Genetta pardina. Recurrent rearrangements make it difficult to define the ancestral chromosomal arrangement in several instances. Only 2 species of pangolins (Pholidota), a sister order of Carnivora, have been studied by chromosome painting. Future use of whole-genome sequencing data is discussed in the context of solving the questions that are beyond resolution of conventional banding techniques and chromosome painting.


Assuntos
Carnívoros/classificação , Carnívoros/genética , Animais , Canidae/classificação , Canidae/genética , Gatos , Coloração Cromossômica , Cromossomos de Mamíferos/genética , Cães , Evolução Molecular , Felidae/classificação , Felidae/genética , Feminino , Humanos , Cariótipo , Masculino , Mephitidae/classificação , Mephitidae/genética , Mustelidae/classificação , Mustelidae/genética , Filogenia , Procyonidae/classificação , Procyonidae/genética , Especificidade da Espécie , Ursidae/classificação , Ursidae/genética , Viverridae/classificação , Viverridae/genética
5.
Mol Phylogenet Evol ; 43(3): 1076-95, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17174109

RESUMO

The Procyonidae (Mammalia: Carnivora) have played a central role in resolving the controversial systematics of the giant and red pandas, but phylogenetic relationships of species within the family itself have received much less attention. Cladistic analyses of morphological characters conducted during the last two decades have resulted in topologies that group ecologically and morphologically similar taxa together. Specifically, the highly arboreal and frugivorous kinkajou (Potos flavus) and olingos (Bassaricyon) define one clade, whereas the more terrestrial and omnivorous coatis (Nasua), raccoons (Procyon), and ringtails (Bassariscus) define another clade, with the similar-sized Nasua and Procyon joined as sister taxa in this latter group. These relationships, however, have not been tested with molecular sequence data. We examined procyonid phylogenetics based on combined data from nine nuclear and two mitochondrial gene segments totaling 6534bp. We were able to fully resolve relationships within the family with strongly supported and congruent results from maximum parsimony, maximum likelihood, minimum evolution, and Bayesian analyses. We identified three distinct lineages within the family: a (Nasua, Bassaricyon) clade, a (Bassariscus, Procyon) clade, and a Potos lineage, the last of which is sister to the other two clades. These findings, which are in strong disagreement with prior fossil and morphology-based assessments of procyonid relationships, reemphasize the morphological and ecological flexibility of these taxa. In particular, morphological similarities between unrelated genera possibly reflect convergence associated with similar lifestyles and diets rather than ancestry. Furthermore, incongruence between the molecular supermatrix and a morphological character matrix comprised mostly of dental characters [Baskin, J.A., 2004. Bassariscus and Probassariscus (Mammalia, Carnivora, Procyonidae) from the early Barstovian (Middle Miocene). J. Vert. Paleo. 24, 709-720] may be due to non-independence among atomized dental characters that does not take into account the high developmental genetic correlation of these characters. Finally, molecular divergence dating analyses using a relaxed molecular clock approach suggest that intergeneric and intrageneric splits in the Procyonidae mostly occurred in the Miocene. The inferred divergence times for intrageneric splits for several genera whose ranges are bisected by the Panamanian Isthmus is significant because they suggest diversification well precedes the Great American Interchange, which has long been considered a primary underlying mechanism for procyonid evolution.


Assuntos
Filogenia , Procyonidae/genética , Animais , Núcleo Celular/genética , Evolução Molecular , Genes Mitocondriais/genética , Variação Genética , Dados de Sequência Molecular , Procyonidae/anatomia & histologia , Procyonidae/classificação , Análise de Sequência de DNA
7.
Mol Phylogenet Evol ; 36(1): 78-89, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15904858

RESUMO

The red panda (Ailurus fulgens) is an endangered species and its present distribution is restricted to isolated mountain ranges in western China (Sichuan, Yunnan, and Tibet provinces) and the Himalayan Mountains chain of Nepal, India, Bhutan, and Burma. To examine the evolutionary history across its current range, and to assess the genetic divergence among current subspecies and population structure among different geographic locations, we sequenced mitochondrial DNA from the control region (CR) and cytochrome (cyt) b gene for 41 individuals in Sichuan, Yunnan, Tibet of China, and Burma. 25 CR haplotypes (10 for cyt b) were identified from 11 geographic locations. Only three haplotypes were shared among sample localities, including one among current subspecies. Nine haplotypes were shared with the study of Su et al. [Mol. Biol. Evol. 18 (2001) 1070]. CR haplotype diversity was high (0.95+/-0.02) and nucleotide diversity among all haplotypes was relatively low (0.018+/-0.009). Phylogenetic confirmed trees show a shallow pattern with very little structure or statistical robustness. The application of two coalescent-based tests for population growth allowed us to interpret this phylogeny as the result of a recent population expansion. Analysis of molecular variance and nested clade analysis failed to detect significant geographic structure in both data sets. The lack of significant differentiation between subspecies does not indicate the presence of evolutionary significant units. We suggest that the present population structure has resulted from habitat fragmentation and expansion from glacial refugia. Due to its habitat requirements it is likely that the red panda has undergone bottlenecks and population expansions several times in the recent past. The present population may exhibit a pattern reminiscent of a relatively recent population expansion.


Assuntos
DNA Mitocondrial/genética , Procyonidae/classificação , Procyonidae/genética , Animais , Ásia , Sequência de Bases , Conservação dos Recursos Naturais , Citocromos b/genética , Evolução Molecular , Variação Genética , Geografia , Haplótipos , Filogenia , RNA de Transferência de Treonina/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
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