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BEN J. WALLACE 《American anthropologist》2007,109(2):368-369
Ecological Nationalisms: Nature, Livelihood, and Identities in South Asia . Gunnel Cederlöf and K. Sivaramakrishnan, eds. Seattle: University of Washington Press, 2006. 399 pp. 相似文献
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ADAM J. VANBERGEN BEN A. WOODCOCK MATTI KOIVULA JARI NIEMELÄ D. JOHAN KOTZE TOM BOLGER VALERIE GOLDEN FLORENCE DUBS GUILLAUME BOULANGER JOSE SERRANO JOSÉ LUÍS LENCINA ARTUR SERRANO CARLOS AGUIAR ANNE‐CATHERINE GRANDCHAMP SILVIA STOFER GYÖZÖ SZÉL EVA IVITS PETRA ADLER JOCHUM MARKUS ALLAN D. WATT 《Ecological Entomology》2010,35(2):226-235
1. Anthropogenic pressures have produced heterogeneous landscapes expected to influence diversity differently across trophic levels and spatial scales. 2. We tested how activity density and species richness of carabid trophic groups responded to local habitat and landscape structure (forest percentage cover and habitat richness) in 48 landscape parcels (1 km2) across eight European countries. 3. Local habitat affected activity density, but not species richness, of both trophic groups. Activity densities were greater in rotational cropping compared with other habitats; phytophage densities were also greater in grassland than forest habitats. 4. Controlling for country and habitat effects, we found general trophic group responses to landscape structure. Activity densities of phytophages were positively correlated, and zoophages uncorrelated, with increasing habitat richness. This differential functional group response to landscape structure was consistent across Europe, indicated by a lack of a country × habitat richness interaction. Species richness was unaffected by landscape structure. 5. Phytophage sensitivity to landscape structure may arise from relative dependency on seed from ruderal plants. This trophic adaptation, rare in Carabidae, leads to lower phytophage numbers, increasing vulnerability to demographic and stochastic processes that the greater abundance, species richness, and broader diet of the zoophage group may insure against. 相似文献
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BEN THUY 《Palaeontology》2011,54(1):215-233
Abstract: Two new genera and species of ophiuroid, Inexpectacantha acrobatica new gen. et sp. and Eirenura papillata new gen et sp., are described on the basis of 39 articulated specimens and several hundreds of arm fragments and isolated skeletal parts. The material was extracted from a lumachellic bed in a late early Pliensbachian succession of argillites at Sedan, French Ardennes. The material is unusually well preserved with even finest structures of the skeleton discernible. Despite the exceptionally detailed morphological data extractable from the material, the higher taxonomic classification in the system of recent ophiuroids could only be tentatively attained. Inexpectacantha acrobatica seems best placed within the Ophioplinthacinae inside the Ophiacanthidae whereas Eirenura papillata shares greatest similarities with the Ophioleucinae. The occurrence of articulated specimens of different sizes, with some of the most delicate skeletal structures left intact, together with completely disarticulated skeletons of the same species suggests that the ophiuroids were preserved as autochthonous faunule among an in situ population of Modiolus sp. during a period of more favourable bottom water conditions in an otherwise largely hostile near‐shore soft‐bottom environment. Based on its small size, the highly flexible arms and the presence of well‐developed hooks on distal arm segments, an epizoic way of life is inferred for I. acrobatica while E. papillata, with its rigid arm structure and the conspicuously large tentacle pores, is interpreted as mostly deposit‐feeding bottom surface dweller. 相似文献
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MONIKA ZAVODNA PAUL ARENS PETER J. VAN DIJK BEN VOSMAN 《Molecular ecology resources》2005,5(2):355-357
Microsatellite markers for Ficus montana and Ficus septica were developed using genomic libraries enriched for di‐, tri‐ and tetranucleotide repeats. The subsets of five and three best scorable primer pairs were characterized on 24 F. montana and 36 F. septica individuals, respectively. For F. montana, loci showed five to 14 alleles per locus and expected heterozygosities ranged between 0.23 and 0.87. For F. septica, loci showed three to five alleles per locus and expected heterozygosities ranged between 0.36 and 0.49. Four primer pairs (two from each subset) cross‐amplified in the other species, indicating transportability of the markers within the genus Ficus. 相似文献
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Abstract: Past studies using penned deer provide conflicting results on the age when reliable predictions about antler growth potential in white-tailed deer (Odocoileus virginianus) can be made. We captured wild whitetail males via aerial net gun on 12 ranches in 5 counties in south Texas, USA, from 1999 to 2007 to determine if a reliable juvenile-to-adult relationship in antler development existed. We individually marked and released captured animals at the trap site after we took antler and body measurements. We recaptured marked animals as possible in subsequent years or until we obtained final measurements after legal harvest. Amount of growth in the first set of antlers in whitetail males was a poor predictor of antler growth at maturity. By 4.5 years of age there were no differences (P > 0.05) in antler measurements regardless of the amount of development of the first set of antlers at 1.5 years. We concluded culling of yearling males based on number of antler points would have little positive effect on overall antler quality in future years. 相似文献
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树鼩细胞周期蛋白T1 cDNA的克隆和序列分析 总被引:1,自引:0,他引:1
树鼩细胞不能感染HIV-1,但支持HIV-1进入靶细胞后的转录,可能是因为树鼩细胞周期蛋白T1(tsCycT1)能结合HIV-1的Tat蛋白。通过设计引物,用RT—PCR技术,获得全长为2175bp tsCycT1基因的cDNA。其核苷酸序列与人的CycT1(hCycT1)基因的cDNA有92.6%的相似性;由此推导出的氨基酸序列有94.1%相似性。其中,hCycT1和tsCycT1氨基端的1—272个氨基酸的相似性高达98.8%,氨基酸第261位点为半胱氨酸。这些结果提示,tsCycT1会和HIV-1的Tat结合,形成高亲和的、锌依赖的复合物,支持HIV-1转录。 相似文献