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1.
Abstract 1. Non‐lethal genetic surveys in insects usually extract DNA from a leg or a piece of wing. Although preferable to lethal sampling, little is known about the effect of leg/wing non‐lethal sampling on fitness‐related traits. 2. Graellsia isabelae (Graells, 1849) is a European moth protected by the Habitats Directive and the Bern Convention. Conservation genetics surveys on this species should therefore use non‐lethal sampling. 3. The present study aimed to (1) quantify the effects of both leg and hind‐wing tail sampling on survivorship and reproductive behaviour of adult males and females, and (2) assess the quality and quantity of DNA obtained from those tissues. 4. Both hind‐wing tails and mid‐legs proved to be good sources of high quality nuclear and mitochondrial DNA. DNA concentration was significantly higher when extracted from a large (130 mm2) piece of the hind‐wing tails than from about half of the mid‐leg. Using mark–release–recapture experiments with adults, it was found that neither mid‐leg nor hind‐wing tail sampling significantly reduced male survivorship or total number of matings. However, although mid‐leg sampling did not significantly affect female survivorship, it had a negative effect on female mating success. 5. Wing‐tail clipping on males appeared to be the best non‐lethal sampling procedure for G. isabelae. It is a fast procedure, similar to natural wing impairment, and did not significantly affect survival or mating behaviour.  相似文献   
2.
Nest-site fidelity and breeding success in White Stork Ciconia ciconia   总被引:1,自引:0,他引:1  
Nest-site fidelity is a life-history trait of birds that may produce benefits in terms of fitness. We studied the relationship between breeding success and nest fidelity in the White Stork Ciconia ciconia . We also studied how other factors such as age, sex, habitat, colony size and productivity in previous breeding attempts might interfere with this relationship. Our results showed that pairs with higher fidelity rates also have lower failure rates, and that breeding failure and productivity in the previous season influenced the frequency of nest change in the following season. In addition, a curvilinear relationship was found between age and nest fidelity. These results suggest that age is a major factor related to nest fidelity and therefore individual experience could explain this behaviour in the White Stork. Changing the nest involves a reproductive cost for which nest fidelity can be considered as an adaptive strategy to increase fitness.  相似文献   
3.
Semiarid environments throughout the world have lost a major part of their woody vegetation and biodiversity due to the effects of wood cutting, cattle grazing and subsistence agriculture. The resulting state is typically used for cattle production, but the productivity of these systems is often very low, and erosion of the unprotected soil is a common problem. Such dry‐land degradation is of great international concern, not only because the resulting state is hardly productive but also because it paves the way to desertification. The natural distribution of the genus Prosopis includes arid and semiarid zones of the Americas, Africa and Asia, but the majority of the Prosopis species are, however, native to the Americas. In order to assess a likely gradient in the response of tree species to precipitation, temperature and their connection to El Niño southern oscillation (ENSO) events, two Prosopis species were chosen along a latitudinal gradient in Latin America, from northern Peru to central Chile: Prosopis pallida from a semi‐arid land in northern and southern Peru and P. chilensis from a semiarid land in central Chile. Growth rings of each species were crossdated at each sampling site using classical dendrochronological techniques. Chronologies were related with instrumental climatic records in each site, as well as with SOI and N34 series. Cross‐correlation, spectral and wavelet analysis techniques were used to assess the relation of growth with precipitation and temperature. Despite the long distance among sites, the two Prosopis species presented similar responses. Thus, the two species' growth is positively correlated to precipitation, while with temperature it is not. In northern Peru, precipitation and growth of P. pallida present a similar cyclic pattern, with a period of around 3 years. On the other hand, P. pallida in southern Peru, and P. chilensis also present this cyclic pattern, but also another one with lower frequency, coinciding with the pattern of precipitation. Both cycles are within the range of the ENSO band.  相似文献   
4.
The origin of manus-only and manus dominated sauropod trackways has been a matter of intense debate since two hyphothesis exist: (a) manus-only and manus-dominated trackways result from a 'swimming' sauropod, and (b) they result from a selective underprint phenomenon that only leaves the manus recorded. Several new sauropod trackways are reported in the Fumanya tracksite area (Maastrichtian), in SE Pyrenees, where both tracks and undertracks are found on the same stratigraphic bedding surface. In one of the trackways, footprint morphology together with the trackway pattern displays a clear succession of manus-only impressions attributed to a sauropod dinosaur in a walking gait. The ichnological comparison between the manus-only trackway with the other complete trackway (manus-pes) display an identical distribution of the manus pattern. This fact clearly points towards an underprint phenomenon as the origin for manus-only trackways, since it is rather unlikely that the same pattern would completely match different locomotion behaviours such as walking and swimming. Therefore, we suggest an interpretation based on the differential loading between the hindfoot and the forefoot on an upper stratigraphic track-level, for the studied manus-only trackway. □ Fumanya tracksite, manus-only trackways, titanosaurs, trackway pattern, underprint, Upper Cretaceous.  相似文献   
5.
6.
Few studies of population structure and genetic diversity exist for frogs in the Amazon of South America, an area renowned for exceptionally high species richness. We isolated seven highly variable tetranucleotide microsatellite loci for the neotropical leaflitter frog, Eleutherodactylus ockendeni using an enrichment method. Three of the repeats are simple, three are compound and one is imperfect. We screened all loci with 175 individuals from one geographical area in the upper Napo of Ecuador and found high polymorphism in all loci (> 14 alleles/locus). These markers are suitable for population genetics studies of E. ockendeni and perhaps other leaflitter frogs of the same genus.  相似文献   
7.
Vila, B., Galobart, À., Oms, O., Poza, B. & Bravo, A.M. 2009: Assessing the nesting strategies of Late Cretaceous titanosaurs: 3‐D clutch geometry from a new megaloolithid eggsite. Lethaia, Vol. 43, pp. 197–208. Detailed mapping and excavation at the egg locality of Font del Bullidor (Vallcebre Syncline, NE Iberian Peninsula) document various clutches with megaloolithid (Megaloolithus siruguei) eggs and provide significant information on the mode of incubation of Late Cretaceous titanosaurs. Clutches of eggs are preserved in a greyish lagoonal mudstone deposited overlying a sinuous channel infill. Despite the lithological uniformity of the mudstone, clutch architecture can be inferred from the topographical position of the eggs within some clutches. Mapping methods underscore the importance of documenting the spatial relationship of the egg‐bearing bed and the mapping plan, as well as an accurate 3‐D coordinate acquisition. Both geometry of the clutches and taphonomic observations on particular eggs indicate that eggs were laid in a shallow pit excavated into the substrate. Most of the eggs were incubated under a cover of sediment before hatching or cracking. This corroborates previous inferences on nesting mode. □Clutch, dinosaurs, eggs, Maastrichtian, Megaloolithus siruguei, Pyrenees.  相似文献   
8.
Abstract

Life history theory predicts that the patterns of resource allocation in animals are associated with different strategies, selected in the course of evolution. In the present study, the life history of Leptinaria unilamellata was characterized under laboratory conditions. We determined the growth, reproduction, and longevity patterns of this species and elucidated the strategy related to the development of embryos, through direct observations and examination of the morphology of the gravid uterus. Furthermore, we attempted to analyze the glycogen and galactogen contents of the albumen gland, digestive gland and cephalopedal mass in order to understand energy allocation to life history traits, for three life stages. Leptinaria unilamellata's life history is characterized by great longevity, a short juvenile phase, early sexual maturity, and repeated reproductive events, with little reproductive effort at each event and some mortality shortly after the first reproduction. In the terraria, we found juveniles but no eggs. However, the results of the anatomical study showed no morphological connection between the embryos and the parental organism. Thus, this species should be described as ovoviviparous rather than viviparous. Egg retention in the parent organism is the primary cause of the release of juveniles, instead of eggs, enabling the offspring to withstand environmental stress. The higher quantity of galactogen found in the adults' albumen gland, as compared to juveniles and senescent individuals, as well as the ratio of glycogen to galactogen, reveal the allocation of energy to reproduction rather than to growth. The remaining energy is directed to the maintenance of omeostasis. Such pattern was confirmed by the low levels of glycogen and galactogen observed in the senescent stage, compared to the juvenile and adult stages. In the life strategy of L. unilamellata, the distribution of the reproductive effort among many events associated with ovoviviparity indicates a long-term investment in reproductive success.  相似文献   
9.
The pink dolphin (Inia geoffrensis) is widely distributed along the Amazon and Orinoco basins, covering an area of approximately 7 million km2. Previous morphological and genetic studies have proposed the existence of at least two evolutionary significant units: one distributed across the Orinoco and Amazon basins and another confined to the Bolivian Amazon. The presence of barriers in the riverine environment has been suggested to play a significant role in shaping present‐day patterns of ecological and genetic structure for this species. In the present study, we examined the phylogeographic structure, lineage divergence time and historical demography using mitochondrial (mt)DNA sequences in different pink dolphin populations distributed in large and small spatial scales, including two neighbouring Brazilian Amazon populations. mtDNA control region (CR) analysis revealed that the Brazilian haplotypes occupy an intermediate position compared to three previously studied geographic locations: the Colombian Amazon, the Colombian Orinoco, and the Bolivian Amazon. On a local scale, we have identified a pattern of maternal isolation between two neighbouring populations from Brazil. Six mtDNA CR haplotypes were identified in Brazil with no sharing between the two populations, as well as specific cytochrome b (cyt b) haplotypes identified in each locality. In addition, we analyzed autosomal microsatellites to investigate male‐mediated gene flow and demographic changes within the study area in Brazil. Data analysis of 14 microsatellite loci failed to detect significant population subdivision, suggesting that male‐mediated gene flow may maintain homogeneity between these two locations. Moreover, both mtDNA and microsatellite data indicate a major demographic collapse within Brazil in the late Pleistocene. Bayesian skyline plots (BSP) of mtDNA data revealed a stable population for Colombian and Brazilian Amazon lineages through time, whereas a population decline was demonstrated in the Colombian Orinoco lineage. Moreover, BSP and Tajima's D and Fu's Fs tests revealed a recent population expansion exclusively in the Bolivian sample. Finally, we estimated that the diversification of the Inia sp. lineage began in the Late Pliocene (approximately 3.1 Mya) and continued throughout the Pleistocene. Published 2011. This article is a US Government work and is in the public domain in the USA. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102 , 812–827.  相似文献   
10.
Time of day is usually not considered an important factor underlying the structure of forest passerine communities. However, this study shows that the positions exploited in trees by some members of a community change during the day in a cyclic pattern. Coal Tit Pants ater, Crested Tit Parus cristatus and Goldcrest Regulus regulus foraged lower and nearer to the trunk at midday than in the first and last hours of the day. Simultanously, there were diurnal changes in the niche breadth (degree of uniformity in the exploitation of the different parts of the trees). The Coal Tit reached the maximum niche breadth values during the central part of the day, with the minimum being recorded at that time for the Crested Tit and the Goldcrest. On the other hand, Treecreepers Certhia sp. did not show significant diurnal variation. These results, together with the changes in activity levels during the day for each species, suggest that time of day plays an important role in the structure of the community, allowing a more uniform use of the habitat and addressing a new interpretation of the interspeciic relationships inside the community, with competitive relationships not showing the same intensity throughout the day.  相似文献   
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