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; 2201â¯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 (â¼3.8 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 TempoRESUMO
The pygmy raccoon (Procyon pygmaeus) of Cozumel Island, Mexico, is among the most endangered carnivores in the world, and causes of its decline are unclear. During 2002 and 2003, we sampled approximately 10% of the remaining population to survey exposure to viral and parasitic pathogens that may have contributed to population decline. We found evidence of exposure to infectious canine hepatitis, canine distemper, feline panleukopenia virus, and Toxoplasma gondii. The latter is suggestive of spillover from domestic cats, which have only recently been introduced to the island. Additional parasites identified include Eimeria nutalli, Placoconus lotoris, Capillaria procyonis, Physaloptera sp., a mite in the family Listrophoridae, and a trematode in the family Heterophyidae. Several of these are typical of the parasite community of the common raccoon (Procyon lotor).