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21.
We present the most comprehensive analysis of higher-level relationships in gall wasps conducted thus far. The analysis was based on detailed study of the skeletal morphology of adults, resulting in 164 phylogenetically informative characters, complemented with a few biological characters. Thirty-seven cynipid species from thirty-one genera, including four genera of the apparently monophyletic Cynipini and almost all of the genera in the other tribes, were examined. The outgroup included exemplar species from three successively more distant cynipoid families: Figitidae (the sister group of the Cynipidae), Liopteridae and Ibaliidae. There was considerable homoplasy in the data, but many groupings in the shortest tree were nonetheless well supported, as indicated by bootstrap proportions and decay indices. Partitioning of the data suggested that the high level of homoplasy is characteristic of the Cynipidae and not the result of the amount of available phylogenetically conservative characters being exhausted. The analysis supported the monophyly of the Cynipini (oak gall wasps) which, together with the Rhoditini (the rose gall wasps), Eschatocerini and Pediaspidini formed a larger monophyletic group of gall inducers restricted to woody representatives of the eudicot subclass Rosidae. The inquilines (Synergini) were indicated to be monophyletic, whereas the Aylacini, primarily herb gall inducers, appeared as a paraphyletic assemblage of basal cynipid groups. The shortest tree suggests that the Cynipidae can be divided into three major lineages: one including the inquilines, the Aylacini genera associated with Rosaceae, and Liposthenes ; one consisting entirely of Aylacini genera, among them Aulacidea , Isocolus and Neaylax ; and one comprising the woody rosid gallers (the oak and rose gall wasps and allies), the Phanacis-Timaspis complex and the Aylacini genera associated with Papaveraceae.  相似文献   
22.
Phylogenetic analyses of molecular data (COI, 16SrDNA, 18SrDNA, and 28SrDNA) show that the hesionid genus Gyptis Marion & Bobretzky in Marion, 1874, and the tribe Gyptini Pleijel, 1998, are nonmonophyletic as currently delineated. We introduce the new tribe Amphidurini and the new genus Neogyptis to accommodate these new findings. Amphidurini is sister to Gyptini and Ophiodromini and includes Amphiduros Hartman, 1959, Amphiduropsis, Pleijel, 2001, Neogyptis gen. nov. , and, possibly, Parahesione Pettibone, 1956. Morphologically, Amphidurini can be separated from Gyptini by the distally, rather than subdistally, inserted ventral cirri, and Neogyptis by the combination of this feature, the presence of a median antenna, and a distal ring with papillae on the proboscis. We redescribe and transfer the four species Gyptis crypta Pleijel, 1993, Gyptis mediterranea Pleijel, 1993, Gyptis plurisetis Hilbig, 1992, and Gyptis rosea (Malm, 1874) from Gyptis to Neogyptis gen. nov. , and describe five new species from shallow waters in Belize, Hong Kong, off Vladivostok, and deep‐sea hydrothermal vents in the Lau Basin off Fiji.  相似文献   
23.
The paper focuses on differences in the way social situations are defined in different cultures and societies. It develops and illustrates some dimensions for comparing social systems in this respect, viz: their inventory of statuses, the repertoires of persons, and the cultural ways in which occasions are distinguished. Some contrasting types of society are compared on these dimensions; and the problem is raised as to the epistemological character of such types, and the importance of the variable of scale. The dual nature of social organization as an organization both of people and of tasks is emphasized.  相似文献   
24.
Terfelt, F., Ahlberg, P. & Eriksson, M.E. 2011: Complete record of Furongian polymerid trilobites and agnostoids of Scandinavia – a biostratigraphical scheme. Lethaia, Vol. 44, pp. 8–14. So far, 112 polymerid trilobite species/subspecies and 13 agnostoid species/subspecies have been recorded from the Furongian (upper Cambrian) of Scandinavia. For the first time, their zonal occurrences are summarized in a biostratigraphical scheme serving as a practical synopsis for students of this interval in time. Ninety‐six of the recorded polymerid trilobite species/subspecies belong to the family Olenidae whereas the remaining 16 are distributed across eight other families. Levels of increased speciation and low diversity (including stratigraphical range gaps) are conspicuous and these may be correlated with recorded physical and chemical anomalies. □Agnostoids, biostratigraphy, Cambrian, Furongian, polymerids, Scandinavia, trilobites.  相似文献   
25.
Bartonella is a genus of vector‐borne bacteria that infect the red blood cells of mammals, and includes several human‐specific and zoonotic pathogens. Bartonella grahamii has a wide host range and is one of the most prevalent Bartonella species in wild rodents. We studied the population structure, genome content and genome plasticity of a collection of 26 B. grahamii isolates from 11 species of wild rodents in seven countries. We found strong geographic patterns, high recombination frequencies and large variations in genome size in B. grahamii compared with previously analysed cat‐ and human‐associated Bartonella species. The extent of sequence divergence in B. grahamii populations was markedly lower in Europe and North America than in Asia, and several recombination events were predicted between the Asian strains. We discuss environmental and demographic factors that may underlie the observed differences.  相似文献   
26.
The genus Sige Malmgren, 1865 is revised and the type species S.fusigera Malmgren, 1865, redescribed from syntypes and newly collected topotype material. Based on examination of type specimens, six species described from other genera are transferred to Sige: Pirakia brunnea Fauchald, 1972; Vitiazia dogieli Ushakov, 1953; Eulalia longocirrata Stop-Bowitz, 1948; Eumida (Eumidaj parvicirrus Perkins, 1984; Eulalia sandwichensis Ushakov, 1975; Eulalia sigeformis Annekova, 1937. The genus Vitiazia Ushakov, 1953, being monotypic, becomes a junior synonym to Sige. Pirakia lanceolata Hartman & Fauchald, 1971 is synonymized with Sige longocirrata (Støp-Bowitz, 1948) and Sige oliveri sp. nov. is described from western Norway and Sweden. Ten species are recognized as belonging to Sige. The relationships of Sige to other genera are discussed.  相似文献   
27.
Abstract.  1. During range expansions of phytophagous insects, secondary or novel hosts may allow colonisation of areas without primary hosts. Because plant species often differ in their relative attractiveness and suitability for insects, insect preference for, and performance on, these hosts can determine recruitment potential in the current and future expansion areas.
2. This study explores the relative roles of female preference and larval performance in an important pine defoliator, Thaumetopoea pityocampa (Denis & Schiffermüller) (Lepidoptera, Notodontidae), which colonises three Pinus species at its current range margin in the Italian Alps: P. nigra (primary host), P. sylvestris (secondary host), and P. mugo (novel host).
3. Host use patterns in multiple insect populations were studied through choice and no-choice oviposition experiments in cages, field surveys of mixed stands, and laboratory and field monitoring of larval growth and mortality. It was predicted that a specific life-history trait – time limitation of short-lived females to lay a single batch of eggs – would act as a component of female performance, and lead to similar rates of host acceptance in no-choice settings.
4. In the choice experiment, P. nigra was accepted the most frequently while P. sylvestris was accepted the least frequently, confirming nest density patterns in the field. Contrary to prediction, females remained discriminating in no-choice settings in spite of time limitation. In contrast, relative growth rate (RGR) and mortality of larvae did not differ significantly among the three hosts, highlighting a discrepancy between female preference and larval performance.
5. Recruitment potential of T. pityocampa in future expansion into stands of P. sylvestris and P. mugo is evaluated by combining host quality, conservatism in oviposition behaviour, habitat suitability, and the opportunity for local adaptation.  相似文献   
28.
This paper develops a statistical model for daily gross primary production (GPP) in boreal and temperate coniferous forests. The model applies the light use efficiency (LUE) approach, which estimates the conversion efficiency of daily absorbed photosynthetically active radiation (APAR) into daily GPP as a product of potential LUE and modifying factors. The latter were derived from daily total APAR and daily mean temperature, vapour pressure deficit (VPD) and soil water content (SWC). Modelling data came from five European eddy covariance measurement towers over 2–8 years. The model was tested against independent data from two AmeriFlux stations. The model with the APAR, temperature and VPD modifiers worked well in almost all the site–year combinations, but the SWC modifier only improved the fit in few cases. Geographical variation was found in the modifiers and potential LUE in site-specific models. When a model was fitted to pooled data, differences between sites could be explained by potential LUE, leaf area and environmental conditions. The test against the AmeriFlux data corroborated this finding. The potential LUE varied from 1.9 to 3.1 g C MJ−1, and a weak correlation was found between foliar nitrogen concentration and potential LUE. Some year-to-year variation remained which could be captured by neither the pooled nor the site-specific models.  相似文献   
29.
30.
We analysed patterns of animal dispersal, vicariance and diversification in the Holarctic based on complete phylogenies of 57 extant non‐marine taxa, together comprising 770 species, documenting biogeographic events from the Late Mesozoic to the present. Four major areas, each corresponding to a historically persistent landmass, were used in the analyses: eastern Nearctic (EN), western Nearctic (WN), eastern Palaeoarctic (EP) and western Palaeoarctic (WP). Parsimony‐based tree fitting showed that there is no significantly supported general area cladogram for the dataset. Yet, distributions are strongly phylogenetically conserved, as revealed by dispersal‐vicariance analysis (DIVA). DIVA‐based permutation tests were used to pinpoint phylogenetically determined biogeographic patterns. Consistent with expectations, continental dispersals (WP?EP and WN?EN) are significantly more common than palaeocontinental dispersals (WN?EP and EN?WP), which in turn are more common than disjunct dispersals (EN?EP and WN?WP). There is significant dispersal asymmetry both within the Nearctic (WN→EN more common than EN→WN) and the Palaeoarctic (EP→WP more common than WP→EP). Cross‐Beringian faunal connections have traditionally been emphasized but are not more important than cross‐Atlantic connections in our data set. To analyse changes over time, we sorted biogeographic events into four major time periods using fossil, biogeographic and molecular evidence combined with a ‘branching clock’. These analyses show that trans‐Atlantic distributions (EN‐WP) were common in the Early‐Mid Tertiary (70‐20 Myr), whereas trans‐Beringian distributions (WN‐EP) were rare in that period. Most EN‐EP disjunctions date back to the Early Tertiary (70‐45 Myr), suggesting that they resulted from division of cross‐Atlantic rather than cross‐Beringian distributions. Diversification in WN and WP increased in the Quaternary (< 3 Myr), whereas in EP and EN it decreased from a maximum in the Early‐Mid Tertiary.  相似文献   
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