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891.
Male‐limited secondary sexual trait interacts with environment in determining female fitness 下载免费PDF全文
Anna Maria Skwierzyńska Jacek Radwan Agata Plesnar‐Bielak 《Evolution; international journal of organic evolution》2018,72(8):1716-1722
Selection for secondary sexual trait (SST) elaboration may increase intralocus sexual conflict over the optimal values of traits expressed from shared genomes. This conflict can reduce female fitness, and the resulting gender load can be exacerbated by environmental stress, with consequences for a population's ability to adapt to novel environments. However, how the evolution of SSTs interacts with environment in determining female fitness is not well understood. Here, we investigated this question using replicate lines of bulb mites selected for increased or decreased prevalence of a male SST—thickened legs used as weapons. The fitness of females from these lines was measured at a temperature to which the mites were adapted (24°C), as well as at two novel temperatures: 18°C and 28°C. We found the prevalence of the SST interacted with temperature in determining female fecundity. At 28°C, females from populations with high SST prevalence were less fecund than females from populations in which the SST was rare, but the reverse was true at 18°C. Thus, a novel environment does not universally depress female fitness more in populations with a high degree of sexually selected dimorphism. We discuss possible consequences of the interaction we detected for adaptation to novel environments. 相似文献
892.
Male advertisement call characters as phylogeographical indicators in European water frogs 总被引:1,自引:0,他引:1
JULIA WYCHERLEY SIMON DORAN TREVOR J. C. BEEBEE 《Biological journal of the Linnean Society. Linnean Society of London》2002,77(3):355-365
Anuran vocalizations are valuable in the determination of species identity and have the potential to discriminate intraspecific variation. We developed novel bioacoustic sampling techniques, based on Fast Fourier Transforms, to increase the precision and sensitivity of male advertisement call analysis and applied the method to European water frogs. This approach robustly separated the three types of north European water frogs (Rana ridibunda, R. lessonae and their viable, fertile hybrid R. esculenta) by their call subunit characteristics. The hybrid frog exhibited a high frequency call component absent from both the parental species. Furthermore, call analysis demonstrated significant intraspecific differences among populations of all three frog types. Call characters of R. ridibunda changed systematically as a function of longitude. This trend may reflect either clinal variation in selection pressures across Europe, or the consequences of drift following postglacial colonization from eastern refugia. High resolution vocalization analysis therefore provides a potentially useful method for investigating intraspecific differentiation and the phylogeographical origins of anuran distributions. © 2002 The Linnean Society of London. Biological Journal of the Linnean Society, 2002, 77 , 355?365. 相似文献
893.
Morphological and behavioural alterations occurred in the fish Tilapia mossambica, following methallibure treatment. A complete loss of sexual dimorphism, absence of reproductive and agonistic behaviours
and a total blanching of the body due to destruction of the melanophores were the changes recorded. Moreover, significant
changes were also induced in the pars intermedia by this drug. These results are discussed in the light of available data. 相似文献
894.
Birgitta S. Tullberg Alison F. Hunter 《Biological journal of the Linnean Society. Linnean Society of London》1996,57(3):253-276
Gregariousness in insects is often associated with aposematism, which has two distinct properties, repellent defence and warning coloration. Theoretically, both repellent defence and warning coloration are expected to facilitate the evolution of gregariousness. This paper investigates whether the likelihood for gregariousness to evolve is higher (1) in the presence of chemical/physical defence and (2) in the presence of warning coloration, in a sample of over 800 tree-living macrolepidopteran species. A new phylogenetic technique for investigating the correlation between two discrete characters, based on independent contrasts, is used. For each of nine contrasts, based on presence/absence of repellent defence that included transitions to gregariousness, the frequency of such transitions was highest in the lineage with repellent defence present. Similarly, out of 12 contrasts based on presence/absence of warning coloration 10 had the highest frequency of transitions to gregariousness in the lineage with warning coloration. Thus, gregariousness is more likely to evolve in lineages with repellent defence and in lineages with warning coloration, but it is concluded that, since these traits are strongly intercorrelated, it is very difficult to distinguish between their separate effects on the evolution of gregariousness. Our findings indicate, however, that potentially, the presence of repellent defence may be sufficient for the evolution of gregariousness. 相似文献
895.
J. Szweykowski K. Buczkowska I. J. Odrzykoski 《Plant Systematics and Evolution》2005,253(1-4):133-158
Detailed analysis of 270 specimens of Conocephalum conicum (L.) Dumort., mainly from the POZW Herbarium revealed some diagnostic differences between two cryptic species originally detected on the basis of isozyme studies. Several diagnostic characters were found in the structure of the archegoniophore, sporophyte and sterile thallus. The most reliable diagnostic features are size and structure of stomatal apparatus of the archegoniophore ‘heads’, type of junction of the air chamber walls with epidermal cells, and the thallus surface details. On the basis of morphological and anatomical diagnostic characters, two formerly cryptic species are recognized following the rules of formal taxonomy. The lectotype of C. conicum preserved in FI was found to possess characteristics of cryptic species C. conicum- species L. Accordingly, the species previously named as C. conicum–species L must bear the name Conocephalum conicum (L.) Dumort. No published name was related to C. conicum – species S, which is therefore described as a new species: Conocephalum salebrosum Szweykowski, Buczkowska &; Odrzykoski. Both species are fully described and their diagnostic characters are illustrated. Distribution maps for both species are given. 相似文献
896.
Absence of a seasonal cycle in the sonic neuromuscular system of the oyster toadfish 总被引:1,自引:1,他引:0
M. S. Johnson T. D. Waybright D.W. Matt † J. J. Feher ‡ M. L. Fine § 《Journal of fish biology》2000,56(1):211-215
No seasonal pattern was found in total swimbladder weight, sonic muscle weight, or spinal sonic motor nucleus neuron soma size of the oyster toadfish Opsanus tau , indicating that additional nonsteroidal factors are also involved in the development of the toadfish sonic neuromuscular system. 相似文献
897.
Juan C. Alonso Marina Magaña Carlos A. Martín Carlos Palacín Javier A. Alonso 《European Journal of Wildlife Research》2006,52(1):43-47
During a long-term study of individually marked, free-living male great bustards captured as chicks and radio-tracked through
several years in Spain, we studied the development with age of two secondary sex traits, the moustachial feathers and the
neck plumage pattern. Juvenile males acquired full adult plumage between their fourth and seventh years. The main changes
occurred at the neck, coinciding with the onset of sexual maturity. The grey colour typical of immature males turned to ivory
white around the fourth to fifth spring, and a gradual increase was appreciated in adults in the brightness of the white colour
of the upper neck and in the contrast between this and a progressively more intense chestnut brown at the neck base. Based
on these changes, we proposed four neck plumage patterns that can be used to differentiate male age classes during the mating
period. The development of moustachial feathers showed more interindividual variability and was not as useful as the neck
plumage to estimate male age. 相似文献
898.
A quantitative genetic model for growth,shape, reaction norms,and other infinite-dimensional characters 总被引:22,自引:0,他引:22
Infinite-dimensional characters are those in which the phenotype of an individual is described by a function, rather than by a finite set of measurements. Examples include growth trajectories, morphological shapes, and norms of reaction. Methods are presented here that allow individual phenotypes, population means, and patterns of variance and covariance to be quantified for infinite-dimensional characters. A quantitative-genetic model is developed, and the recursion equation for the evolution of the population mean phenotype of an infinite-dimensional character is derived. The infinite-dimensional method offers three advantages over conventional finite-dimensional methods when applied to this kind of trait: (1) it describes the trait at all points rather than at a finite number of landmarks, (2) it eliminates errors in predicting the evolutionary response to selection made by conventional methods because they neglect the effects of selection on some parts of the trait, and (3) it estimates parameters of interest more efficiently. 相似文献
899.
Mahrad Nassirkhani Reza Vafai Shoushtari Mahtab Rahmat Abadi 《Zoology in the Middle East.》2016,62(1):78-84
The pseudoscorpion Hysterochelifer afghanicus Beier, 1966 is redescribed and illustrated based on 21 specimens (13♂, 8♀) collected from different sites in northern, western, and southern Iran. A number of morphological characters and new provincial records are given. In addition, a key for 13 species of the pseudoscorpion genus Hysterochelifer Chamberlin, 1932 is proposed. 相似文献
900.
Birgitta Siixn-Tullberg 《Evolution; international journal of organic evolution》1993,47(4):1182-1191
In a published paper, a method for testing the correlation between two discrete characters was presented and applied to test whether in butterfly larvae origins of gregariousness are concentrated to lineages with aposematic coloration. The relationship was found to be nonsignificant. However, the butterfly data on which the test was applied had been compiled in another study to investigate evolutionary sequences and was biased, because there was an overrepresentation of aposematic, as compared to cryptic, branches in the sample. In the paper presented here, aposematic and cryptic clades of the original phylogeny were resolved to the same degree, and the resulting set of branches may be regarded as unbiased with respect to the hypothesis being tested. A method for testing the contingency of states in two characters was then applied to the new data set, resulting in a highly significant relationship between origins of gregariousness and aposematic coloration. I argue that when using statistical methods on phylogenetic data, it is crucial to resolve various parts of the phylogeny to the same comparable systematic unit in order not to get a distorted sample of taxa/branches. 相似文献