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Eastern chipmunks are small forest rodents for which ecological data at multiple spatial scales exist, but no molecular markers have been developed that provide adequate resolution to examine genetic structure at fine scales in this species. Thus, we developed 12 variable microsatellite loci, which amplified in three multiplexed reactions, and screened them in 27 individuals from northern Indiana, USA. Observed heterozygosities across loci ranged from 0.26 to 0.91 and number of alleles per locus ranged from three to 10. We will use these markers along with ecological data to understand population dynamics of eastern chipmunks at small spatial scales.  相似文献   
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Although microsatellite markers have become exceedingly popular in molecular studies of wild organisms, their development in some taxonomic groups is challenging. This is partly because of repetitive flanking sequences, which lead to the simultaneous amplification of alleles from multiple loci. Until now, these microsatellite DNA families have been considered unsuitable for population genetics studies, but here we describe our development of these repetitive flanking sequences (ReFS) as novel molecular markers. We illustrate the utility of these markers by using them to address an outstanding taxonomic question in the moth genus Schrankia.  相似文献   
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ABSTRACT. Our knowledge of the diversity of amoeboid protists is rapidly expanding as new and old habitats are more fully explored. In 2003, while investigating the cause of an amoeboid disease afflicting lobsters on the East Coast, samples were examined for the presence of amoebae from the carapace washings of the American lobster, Homarus americanus . During this survey a unique community of gymnamoebae was discovered. Among the new taxa discovered was a small Thecamoeba -like organism with a single posteriorly directed pseudopodium. Although resembling Parvamoeba rugata , this amoeba displayed distinctive morphology from that isolate or any other amoebozoan. Phylogenetic analysis shows this amoeba is distantly related to the Thecamoebidae. In this paper we describe the unique morphology of a second species of Parvamoeba and discuss its phylogenetic position with respect to the "Amoebozoa."  相似文献   
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ABSTRACT Knowledge of the distribution and pathology of West Nile virus (WNV) in black bears is a necessary tool that allows wildlife managers to implement a management plan, set harvest quotas, and relocate nuisance bears. We studied the presence and significance of WNV titers in free-roaming black bears (Ursus americanus) in northeastern Wisconsin between February 2003 and March 2005. Serum neutralizing antibodies to WNV, with confirmation by plaque-reduction neutralization test to both WNV and Saint Louis encephalitis, identified exposure in 13 of 74 (17.6%) bears. This compares with a 6% infection rate in black bears in Virginia and 22% in European brown bears (Ursus arctos). Pathologic effects from exposure to WNV were not seen in any of the black bears studied.  相似文献   
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