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1.
Microsatellite loci were isolated from Carnaby's black cockatoo (Calyptorhynchus latirostris: Aves), a highly valued, endangered, and endemic species of bird from Western Australia. This study describes three dinucleotide and one tetranucleotide microsatellite loci for which the primers produced clear and polymorphic amplification patterns with between two and nine alleles and moderate levels of variability. Two additional dinucleotide markers which were monomorphic in the Carnaby's cockatoo were able to amplify and were polymorphic in two other species of black cockatoo, greatly increasing the utility of these markers.  相似文献   
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The ground parrot (Pezoporus wallicus) has a coastal distribution in Victoria and has declined in range since European colonization. Its habitat consists of two major vegetation communities: coastal heathland and sedgeland. These are further divided into various sub-communities. These habitats contained high densities of cyperaceous and restionaceous plants, the seeds of which form the bulk of the bird's diet. Seeds and small fruits of some dicotyledonous plants and grasses are also eaten. Seed production by sedges remains fairly constant over time in sedgelands but varies in heathland, depending on time since burning. This variation is reflected by parallel changes in ground parrot population density. Both long unburnt and very frequently burnt heathlands are unsuitable for ground parrots. The birds also require dense vegetation cover. Ground parrots appear to live in territorial breeding pairs with enforced natal dispersal. This is an adaptation to an environment where habitat is patchily distributed in space and variable in quality over time.  相似文献   
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Clitoria yellow vein virus (CYW) was found in Clitoria ternatea and Abrus precatorius in coastal districts of Kenya, but was not detected in food legume crops. When transmitted by inoculation of sap, CYW infected many species in the Papilionaceae, commonly causing yellowing of secondary and smaller leaf veins. All the economically important food legumes grown in the area of occurrence were very susceptible, so that CYW is potentially very important. The virus also infected okra (Hibiscus esculentus) and species in the Solanaceae, but none of many species of Cucurbitaceae. CYW is serologically closely related to cocoa yellow mosaic and kennedya yellow mottle viruses, and more distantly to okra mosaic and desmodium yellow mottle viruses. Other properties of CYW^ typical of the tymoviruses include particle morphology (particle diameter c. 28 nm; two components) with sedimentation coefficients of 50S (top) and 109S (bottom); molecular weight of protein sub-units c. 20000; thermal inactivation point c. 72 oC; and longevity in vitro c. 3 wk.  相似文献   
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Violent spore discharge in the Hyphomycetes Alternaria tenuis,Memnoniella supsimplex, Curvularia lunata, C. geniculata, Corynesporacassiicola, and Zygophiala jamaicensis occurs after transferfrom a humid to a dry atmosphere. Mechanisms of discharge aresuggested.  相似文献   
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Abstract: Fishers (Martes pennanti) were extirpated from much of southern Ontario, Canada, prior to the 1950s. We hypothesised that the recent recolonization of this area originated from an expansion of the population in Algonquin Provincial Park, which historically served as a refuge for fishers. To test this hypothesis, we created a sampling lattice to encompass Algonquin and the surrounding area, and we collected contemporaneous DNA samples. We sampled fishers from each of 35 sites and genotyped them at 16 microsatellite loci. Using a Bayesian assignment approach, with no a priori geographic information, we inferred 5 discrete genetic populations and used genetic population assignment as a means to cluster sites together. We concluded that the Algonquin Park fisher population has not been a substantial source for recolonization and expansion, which has instead occurred from a number of remnant populations within Ontario, Quebec, and most recently from the Adirondacks in New York, USA. The genetic structure among sampling sites across the entire area revealed a pattern of isolation-by-distance (IBD). However, an examination of the distribution of genetic structure (FST/1- FST) at different distances showed higher rates of gene flow than predicted under a strict IBD model at small distances (40 km) within clusters and at larger distances up to 100 km among clusters. This pattern of genetic structure suggests increased migration and gene flow among expanding reproductive fronts.  相似文献   
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Here, I examine overlapping resource use of forest and cultivated resources by villagers and tonkean macaques (Macaca tonkeana) in Lore Lindu National Park, Sulawesi, Indonesia. An integrative research design was employed, using methods from primatology and cultural anthropology, in conjunction with quantitative measurements of cacao crop loss. The results indicate that the current patterns of overlapping resource use may not be severely affecting the tonkean macaques or villagers in Lindu. The research does, however, point to possible future difficulty if cacao crop raiding by macaques increases, and as changing socioeconomic trends and loss of traditional folklore result in further modification of macaque habitat. Successful strategies to ameliorate human–macaque conflict may require efforts aimed at the adoption of alternative buffer zone crops that use shade-management systems, the deliberate protection of important macaque food species, and increasing local tolerance to crop raiding by exploring the role of macaques in forest regeneration.  相似文献   
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