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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.
J Wildl Dis ; 41(3): 615-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16244074

RESUMO

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).


Assuntos
Anticorpos Antiprotozoários/sangue , Fezes/parasitologia , Doenças Parasitárias em Animais/epidemiologia , Guaxinins/parasitologia , Animais , Feminino , Humanos , Masculino , México/epidemiologia , Estudos Soroepidemiológicos
3.
Mar Pollut Bull ; 89(1-2): 160-167, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25455822

RESUMO

Palmyra Atoll, in the Central Pacific, is a unique marine ecosystem because of its remarkably intact food web and limited anthropogenic stressors. However during World War II the atoll was structurally reconfigured into a military installation and questions remain whether this may have impacted the health of the atoll's ecosystems and species. To address the issue we assessed green sea turtle (n=157) health and exposure to contaminants at this foraging ground from 2008 to 2012. Physical exams were performed and blood was sampled for testosterone analysis, plasma biochemistry analysis, hematology and heavy metal exposure. Hematological and plasma chemistries were consistent with concentrations reported for healthy green turtles. Heavy metal screenings revealed low concentrations of most metals, except for high concentrations of iron and aluminum. Body condition indices showed that <1% of turtles had poor body condition. In this study, we provide the first published blood values for a markedly healthy sea turtle population at a remote Central Pacific Atoll.


Assuntos
Metais Pesados/sangue , Tartarugas/fisiologia , Animais , Análise Química do Sangue , Peso Corporal , Conservação dos Recursos Naturais , Ecossistema , Meio Ambiente , Feminino , Cadeia Alimentar , Masculino , Metais Pesados/toxicidade , Instalações Militares , Ilhas do Pacífico
4.
J R Soc Interface ; 11(93): 20130888, 2014 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-24451389

RESUMO

Population connectivity and spatial distribution are fundamentally related to ecology, evolution and behaviour. Here, we combined powerful genetic analysis with simulations of particle dispersal in a high-resolution ocean circulation model to investigate the distribution of green turtles foraging at the remote Palmyra Atoll National Wildlife Refuge, central Pacific. We analysed mitochondrial sequences from turtles (n = 349) collected there over 5 years (2008-2012). Genetic analysis assigned natal origins almost exclusively (approx. 97%) to the West Central and South Central Pacific combined Regional Management Units. Further, our modelling results indicated that turtles could potentially drift from rookeries to Palmyra Atoll via surface currents along a near-Equatorial swathe traversing the Pacific. Comparing findings from genetics and modelling highlighted the complex impacts of ocean currents and behaviour on natal origins. Although the Palmyra feeding ground was highly differentiated genetically from others in the Indo-Pacific, there was no significant differentiation among years, sexes or stage-classes at the Refuge. Understanding the distribution of this foraging population advances knowledge of green turtles and contributes to effective conservation planning for this threatened species.


Assuntos
DNA Mitocondrial/genética , Modelos Genéticos , Filogenia , Tartarugas/genética , Animais , Ilhas do Pacífico , Oceano Pacífico
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