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1.
Emerg Infect Dis ; 23(9): 1611-1612, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28820367

RESUMO

White-nose syndrome, first diagnosed in North America in 2006, causes mass deaths among bats in North America. We found the causative fungus, Pseudogymnoascus destructans, in a 1918 sample collected in Europe, where bats have now adapted to the fungus. These results are consistent with a Eurasian origin of the pathogen.


Assuntos
Ascomicetos/genética , Quirópteros/microbiologia , DNA Fúngico/genética , Micoses/história , Micoses/veterinária , Animais , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Ascomicetos/patogenicidade , DNA Fúngico/isolamento & purificação , França/epidemiologia , História do Século XIX , História do Século XX , História do Século XXI , Micoses/microbiologia , Micoses/mortalidade , América do Norte/epidemiologia , Nariz/microbiologia , Nariz/patologia , Análise de Sequência de DNA , Síndrome
2.
Mol Phylogenet Evol ; 66(1): 161-81, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23063883

RESUMO

Although the status of Crinoidea (sea lilies and featherstars) as sister group to all other living echinoderms is well-established, relationships among crinoids, particularly extant forms, are debated. All living species are currently placed in Articulata, which is generally accepted as the only crinoid group to survive the Permian-Triassic extinction event. Recent classifications have recognized five major extant taxa: Isocrinida, Hyocrinida, Bourgueticrinina, Comatulidina and Cyrtocrinida, plus several smaller groups with uncertain taxonomic status, e.g., Guillecrinus, Proisocrinus and Caledonicrinus. Here we infer the phylogeny of extant Crinoidea using three mitochondrial genes and two nuclear genes from 59 crinoid terminals that span the majority of extant crinoid diversity. Although there is poor support for some of the more basal nodes, and some tree topologies varied with the data used and mode of analysis, we obtain several robust results. Cyrtocrinida, Hyocrinida, Isocrinida are all recovered as clades, but two stalked crinoid groups, Bourgueticrinina and Guillecrinina, nest among the featherstars, lending support to an argument that they are paedomorphic forms. Hence, they are reduced to families within Comatulida. Proisocrinus is clearly shown to be part of Isocrinida, and Caledonicrinus may not be a bourgueticrinid. Among comatulids, tree topologies show little congruence with current taxonomy, indicating that much systematic revision is required. Relaxed molecular clock analyses with eight fossil calibration points recover Articulata with a median date to the most recent common ancestor at 231-252mya in the Middle to Upper Triassic. These analyses tend to support the hypothesis that the group is a radiation from a small clade that passed through the Permian-Triassic extinction event rather than several lineages that survived. Our tree topologies show various scenarios for the evolution of stalks and cirri in Articulata, so it is clear that further data and taxon sampling are needed to recover a more robust phylogeny of the group.


Assuntos
Evolução Biológica , Equinodermos/classificação , Filogenia , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Equinodermos/genética , Fósseis , Funções Verossimilhança , Alinhamento de Sequência , Análise de Sequência de DNA
3.
Proc Natl Acad Sci U S A ; 107(11): 5041-6, 2010 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-20202924

RESUMO

Comparative population genetics of ecological guilds can reveal generalities in patterns of differentiation bearing on hypotheses regarding the origin and maintenance of community diversity. Contradictory estimates of host specificity and beta diversity in tropical Lepidoptera (moths and butterflies) from New Guinea and the Americas have sparked debate on the role of host-associated divergence and geographic isolation in explaining latitudinal diversity gradients. We sampled haplotypes of mitochondrial cytochrome c oxidase I from 28 Lepidoptera species and 1,359 individuals across four host plant genera and eight sites in New Guinea to estimate population divergence in relation to host specificity and geography. Analyses of molecular variance and haplotype networks indicate varying patterns of genetic structure among ecologically similar sympatric species. One-quarter lacked evidence of isolation by distance or host-associated differentiation, whereas 21% exhibited both. Fourteen percent of the species exhibited host-associated differentiation without geographic isolation, 18% showed the opposite, and 21% were equivocal, insofar as analyses of molecular variance and haplotype networks yielded incongruent patterns. Variation in dietary breadth among community members suggests that speciation by specialization is an important, but not universal, mechanism for diversification of tropical Lepidoptera. Geographically widespread haplotypes challenge predictions of vicariance biogeography. Dispersal is important, and Lepidoptera communities appear to be highly dynamic according to the various phylogeographic histories of component species. Population genetic comparisons among herbivores of major tropical and temperate regions are needed to test predictions of ecological theory and evaluate global patterns of biodiversity.


Assuntos
DNA Mitocondrial/genética , Ecossistema , Genética Populacional , Lepidópteros/genética , Animais , Geografia , Haplótipos/genética , Dados de Sequência Molecular , Nova Guiné , Especificidade da Espécie
4.
J Parasitol ; 101(3): 327-35, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25634599

RESUMO

The relative importance of environmental factors and host factors in explaining variation in prevalence and intensity of flea parasitism in small mammal communities is poorly established. We examined these relationships in an East African savanna landscape, considering multiple host levels: across individuals within a local population, across populations within species, and across species within a landscape. We sampled fleas from 2,672 small mammals of 27 species. This included a total of 8,283 fleas, with 5 genera and 12 species identified. Across individual hosts within a site, both rodent body mass and season affected total intensity of flea infestation, although the explanatory power of these factors was generally modest (<10%). Across host populations in the landscape, we found consistently positive effects of host density and negative effects of vegetation cover on the intensity of flea infestation. Other factors explored (host diversity, annual rainfall, anthropogenic disturbance, and soil properties) tended to have lower and less consistent explanatory power. Across host species in the landscape, we found that host body mass was strongly positively correlated with both prevalence and intensity of flea parasitism, while average robustness of a host species to disturbance was not correlated with flea parasitism. Cumulatively, these results provide insight into the intricate roles of both host and environmental factors in explaining complex patterns of flea parasitism across landscape mosaics.


Assuntos
Infestações por Pulgas/veterinária , Doenças dos Roedores/parasitologia , Animais , Tamanho Corporal , Ecossistema , Feminino , Infestações por Pulgas/epidemiologia , Infestações por Pulgas/parasitologia , Pradaria , Interações Hospedeiro-Patógeno , Quênia/epidemiologia , Masculino , Plantas/classificação , Prevalência , Chuva , Doenças dos Roedores/epidemiologia , Roedores , Estações do Ano , Sifonápteros/classificação , Solo/classificação
5.
Zookeys ; (324): 1-83, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24003317

RESUMO

We present the first comprehensive taxonomic revision and review the biology of the olingos, the endemic Neotropical procyonid genus Bassaricyon, based on most specimens available in museums, and with data derived from anatomy, morphometrics, mitochondrial and nuclear DNA, field observations, and geographic range modeling. Species of Bassaricyon are primarily forest-living, arboreal, nocturnal, frugivorous, and solitary, and have one young at a time. We demonstrate that four olingo species can be recognized, including a Central American species (Bassaricyon gabbii), lowland species with eastern, cis-Andean (Bassaricyon alleni) and western, trans-Andean (Bassaricyon medius) distributions, and a species endemic to cloud forests in the Andes. The oldest evolutionary divergence in the genus is between this last species, endemic to the Andes of Colombia and Ecuador, and all other species, which occur in lower elevation habitats. Surprisingly, this Andean endemic species, which we call the Olinguito, has never been previously described; it represents a new species in the order Carnivora and is the smallest living member of the family Procyonidae. We report on the biology of this new species based on information from museum specimens, niche modeling, and fieldwork in western Ecuador, and describe four Olinguito subspecies based on morphological distinctions across different regions of the Northern Andes.

6.
Zool J Linn Soc ; 154(2): 353-385, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32287392

RESUMO

Hog-badgers (mustelid carnivorans classified in the genus Arctonyx) are distributed throughout East and Southeast Asia, including much of China, the eastern Indian Subcontinent, Indochina and the large continental Asian island of Sumatra. Arctonyx is usually regarded as monotypic, comprising the single species A. collaris F. Cuvier, 1825, but taxonomic boundaries in the genus have never been revised on the basis of sizeable series from throughout this geographical range. Based on a review of most available specimens in world museums, we recognize three distinctive species within the genus, based on craniometric analyses, qualitative craniodental features, external comparisons, and geographical and ecological considerations. Arctonyx albogularis (Blyth, 1853) is a shaggy-coated, medium-sized badger widely distributed in temperate Asia, from Tibet and the Himalayan region to eastern and southern China. Arctonyx collaris F. Cuvier, 1825, is an extremely large, shorter-haired badger, distributed throughout Southeast Asia, from eastern India to Myanmar, Thailand, Vietnam, Cambodia and Laos. The world's largest extant badger, A. collaris co-occurs with A. albogularis in eastern India and probably in southern China, and fossil comparisons indicate that its geographical range may have extended into central China in the middle Pleistocene. The disjunctly distributed species Arctonyx hoevenii (Hubrecht, 1891), originally described within the order 'Edentata' by a remarkable misunderstanding, is the smallest and darkest member of the genus and is endemic to the Barisan mountain chain of Sumatra. Apart from A. hoevenii, no other Arctonyx occurs on the Sunda Shelf below peninsular Thailand. The natural history of each species of Arctonyx, so far as is known, is briefly reviewed. No claim to original US Government works.

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