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1.
Mol Phylogenet Evol ; 109: 388-403, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28119108

RESUMO

The tortricid moth genus Syndemis has ten described species, with two polyphagous species in Europe and North America respectively. We sequenced five nuclear and four mitochondrial genes for Syndemis samples across both continents and discovered unexpected, extensive diversification restricted to California. DNA evidence supports five new, undescribed, species endemic to California, while the rest of North America and Europe have only one species each. Further, the nuclear genes are less variable and yield contrasting phylogenetic signal compared to mitochondrial DNA for basal relationships between taxa across the genus. Such conflict strongly suggests that male and female moths exhibit radically different levels of philopatry. Our results highlight the importance of sex-specific behavior, and the need for inclusion of multiple genes to fully understand species boundaries, their causes, and the process of speciation. While mtDNA introgression often is invoked to explain incongruous haplotype distributions, our study shows that nuclear DNA selective sweeps, or swamping, can occur while mtDNA and ecology preserve an ancient divergence that is not discernable in nuclear DNA. This study further demonstrates that diversification of herbivores may occur on relictual, declining hostplants, which contrasts with the dominant co-speciation model.


Assuntos
Especiação Genética , Mariposas/fisiologia , Animais , Sequência de Bases , California , DNA Mitocondrial , Feminino , Genes Mitocondriais , Haplótipos , Masculino , Mariposas/genética , Filogenia , Análise de Sequência de DNA , Caracteres Sexuais , Árvores/parasitologia
2.
BMC Evol Biol ; 15: 73, 2015 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-25907684

RESUMO

BACKGROUND: The Mormon Metalmark (Apodemia mormo) species complex occurs as isolated and phenotypically variable colonies in dryland areas across western North America. Lange's Metalmark, A. m. langei, one of the 17 subspecies taxonomically recognized in the complex, is federally listed under the U.S. Endangered Species Act of 1973. Metalmark taxa have traditionally been described based on phenotypic and ecological characteristics, and it is unknown how well this nomenclature reflects their genetic and evolutionary distinctiveness. Genetic variation in six microsatellite loci and mitochondrial cytochrome oxidase subunit I sequence was used to assess the population structure of the A. mormo species complex across 69 localities, and to evaluate A. m. langei's qualifications as an Evolutionarily Significant Unit. RESULTS: We discovered substantial genetic divergence within the species complex, especially across the Continental Divide, with population genetic structure corresponding more closely with geographic proximity and local isolation than with taxonomic divisions originally based on wing color and pattern characters. Lange's Metalmark was as genetically divergent as several other locally isolated populations in California, and even the unique phenotype that warranted subspecific and conservation status is reminiscent of the morphological variation found in some other populations. CONCLUSIONS: This study is the first genetic treatment of the A. mormo complex across western North America and potentially provides a foundation for reassessing the taxonomy of the group. Furthermore, these results illustrate the utility of molecular markers to aid in demarcation of biological units below the species level. From a conservation point of view, Apodemia mormo langei's diagnostic taxonomic characteristics may, by themselves, not support its evolutionary significance, which has implications for its formal listing as an Endangered Species.


Assuntos
Evolução Biológica , Borboletas/classificação , Borboletas/genética , Espécies em Perigo de Extinção , Animais , Conservação dos Recursos Naturais , DNA Mitocondrial/genética , Variação Genética , Genética Populacional , Repetições de Microssatélites , Filogenia , Estados Unidos
3.
Zookeys ; (461): 1-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25561859

RESUMO

We discuss 45 Costa Rican species of Ethmia Hübner, 1819, including 23 previously described: Ethmiadelliella (Fernald), Ethmiabittenella (Busck), Ethmiafestiva Busck, Ethmiascythropa Walsingham, Ethmiaperpulchra Walsingham, Ethmiaterpnota Walsingham, Ethmiaelutella Busck, Ethmiajanzeni Powell, Ethmiaungulatella Busck, Ethmiaexornata (Zeller), Ethmiaphylacis Walsingham, Ethmiamnesicosma Meyrick, Ethmiachemsaki Powell, Ethmiabaliostola Walsingham, Ethmiaduckworthi Powell, Ethmiasandra Powell, Ethmianigritaenia Powell, Ethmiacatapeltica Meyrick, Ethmialichyi Powell, Ethmiatransversella Busck, Ethmiasimilatella Busck, Ethmiahammella Busck, Ethmialinda Busck, and 22 new species: Ethmiablaineorum, Ethmiamillerorum, Ethmiadianemillerae, Ethmiaadrianforsythi, Ethmiastephenrumseyi, Ethmiaberndkerni, Ethmiadimauraorum, Ethmiabillalleni, Ethmiaehakernae, Ethmiahelenmillerae, Ethmiajohnpringlei, Ethmialaphamorum, Ethmiapetersterlingi, Ethmialesliesaulae, Ethmiaturnerorum, Ethmianormgershenzi, Ethmianicholsonorum, Ethmiahendersonorum, Ethmiarandyjonesi, Ethmiarandycurtisi, Ethmiamiriamschulmanae and Ethmiatilneyorum. We illustrate all species and their male and female genitalia, along with distribution maps of Costa Rican localities. Immature stages are illustrated for 11 species, and food plants are listed when known. Gesneriaceae is added as a new food plant family record for Ethmia. CO1 nucleotide sequences ("DNA barcodes") were obtained for 41 of the species.

4.
J Urol ; 188(4 Suppl): 1500-4, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22910268

RESUMO

PURPOSE: Guidelines for staging Wilms tumor mandate regional lymph node sampling at nephrectomy. However, the usefulness of preoperative computerized tomography in staging lymph nodes has not been rigorously investigated. Thus, we correlated preoperative computerized tomography and pathological lymph node findings to establish a radiological criterion for pathological lymph node enlargement. MATERIALS AND METHODS: We reviewed the medical records of children with Wilms tumor at our institution who underwent pre-chemotherapy surgery with lymph node sampling and had preoperative computerized tomography with contrast medium available for interpretation. Computerized tomography was independently reviewed by 2 radiologists blinded to the pathological findings. We collected data on the diameter of the largest regional lymph node identified and this measurement was correlated with the pathological results. RESULTS: A total of 52 children (25 male, 27 female) with a median age of 3.1 years (range 0.4 to 9.6) were identified. The median largest regional lymph node diameter was 6 mm (range 2 to 15). Of the children 10 (19.2%) had metastatic involvement of sampled lymph nodes. A radiological cutoff of 7 mm for lymph node positivity corresponded to a negative predictive value of 89.0%, a sensitivity of 70.0% and a specificity of 57.1%. A ROC curve was constructed with these data describing the prognostic ability of the diameter of the largest regional lymph node on preoperative computerized tomography to determine lymph node positivity in Wilms tumor, which revealed an AUC of 0.67 (95% CI 0.48-0.87, p = 0.09). CONCLUSIONS: By defining a radiological size cutoff for suspicious lymph nodes, preoperative computerized tomography for staging lymph nodes in Wilms tumor demonstrates potential clinical usefulness through risk stratification for therapy and future study design.


Assuntos
Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Tomografia Computadorizada por Raios X , Tumor de Wilms/diagnóstico por imagem , Tumor de Wilms/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Linfonodos/patologia , Masculino , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Estudos Retrospectivos
5.
PLoS One ; 6(1): e16361, 2011 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-21298019

RESUMO

BACKGROUND: The light brown apple moth (LBAM), Epiphyas postvittana (Walker), is native to Australia but invaded England, New Zealand, and Hawaii more than 100 years ago. In temperate climates, LBAM can be a major agricultural pest. In 2006 LBAM was discovered in California, instigating eradication efforts and quarantine against Hawaiian agriculture, the assumption being that Hawaii was the source of the California infestation. Genetic relationships among populations in Hawaii, California, and New Zealand are crucial to understanding LBAM invasion dynamics across the Pacific. METHODOLOGY/PRINCIPAL FINDINGS: We sequenced mitochondrial DNA (mtDNA) from 1293 LBAM individuals from California (695), Hawaii (448), New Zealand (147), and Australia (3) to examine haplotype diversity and structure among introduced populations, and evaluate the null hypothesis that invasive populations are from a single panmictic source. However, invasive populations in California and New Zealand harbor deep genetic diversity, whereas Hawaii shows low level, shallow diversity. CONCLUSIONS/SIGNIFICANCE: LBAM recently has established itself in California, but was in Hawaii and New Zealand for hundreds of generations, yet California and New Zealand show similar levels of genetic diversity relative to Hawaii. Thus, there is no clear relationship between duration of invasion and genetic structure. Demographic statistics suggest rapid expansion occurring in California and past expansions in New Zealand; multiple introductions of diverse, genetically fragmented lineages could contribute to these patterns. Hawaii and California share no haplotypes, therefore, Hawaii is not the source of the California introduction. Paradoxically, Hawaii and California share multiple haplotypes with New Zealand. New Zealand may be the source for the California and Hawaii infestations, but the introductions were independent, and Hawaii was invaded only once. This has significant implications for quarantine, and suggests that probability of invasion is not directly related to geographic distance. Surprisingly, Hawaiian LBAM populations have much lower genetic diversity than California, despite being older.


Assuntos
Agricultura , Genes de Insetos/genética , Espécies Introduzidas , Mariposas/fisiologia , Animais , California , Genética Populacional , Haplótipos , Havaí , Espécies Introduzidas/estatística & dados numéricos , Mariposas/genética
6.
Oecologia ; 81(4): 490-493, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28312642

RESUMO

In 1985 and 1986, more than 180 adults of Prodoxus y-inversus Riley eclosed from cocoons of the 1969 generation in Yucca baccata, after prepupal larvae spent 16 and 17 years in diapause, intervals prior to mass emergence that are unmatched by any other insect on record. The emergences, which occurred during 15- to 16-day periods, followed many years of virtually no maturation by other individuals of the colony, and the size of the moths was not diminished by the long wait. Successful delay of development and synchronous emergence by many individuals indicates that whole populations can postpone activities through long periods of conditions that would be adverse for adult activity.

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