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1.
Abstract.  Fifty-four genera of the bee family Apidae comprising almost all tribes were analysed based on 77 traditional and one new character of the mature larvae. Nine, especially cleptoparasitic species, were newly added. Analyses were performed by maximum parsimony and Bayesian inference. Trees inferred from the analysis of the complete dataset were rooted by taxa from the families Melittidae and Megachilidae. Unrooted trees inferred from the analysis of the partial dataset (excluding outgroup taxa) are also presented to preclude possible negative effects of the outgroup on the topology of the ingroup. Only the subfamily Nomadinae was statistically well supported. The monophyly of the subfamilies Xylocopinae and Apinae was not topologically recovered. The monophyly of the tribe Tetrapediini was supported, and this tribe was found to be related to xylocopine taxa. At the very least, larval morphology suggests that Tetrapedia is not a member of the subfamily Apinae. Our analyses support the monophyly of the Eucerine line (Emphorini, Eucerini, Exomalopsini, Tapinotaspidini) and of the Apine line (Anthophorini, Apini, Bombini, Centridini, Euglossini, Meliponini). All analyses support the monophyly of totally cleptoparasitic tribes of the subfamily Apinae. We named this group the Melectine line (Ericrocidini, Isepeolini, Melectini, Osirini, Protepeolini, Rhathymini). In previous studies all these cleptoparasitic tribes were considered independent evolutionary lineages. Our results suggest that their similarities with hosts in morphology and pattern are probably the result of convergence and host–parasite co-evolution than phylogenetic affinity. According to the present analysis, the cleptoparasitism has evolved independently only six times within the family Apidae.  相似文献   
2.
ALFRÉD TRNKA  PAVOL PROKOP 《Ibis》2011,153(3):627-630
We documented and experimentally tested the use of snake skins in construction of nests in a Great Reed Warbler Acrocephalus arundinaceus population in southwestern Slovakia. There was no difference in predation rates of artificial nests that did or did not contain sloughs. We suggest that snake skins in Great Reed Warbler nests may serve as a post‐pairing signal revealing female parental quality.  相似文献   
3.
The paper describes a new member of a group of Lower Palaeozoic marine fossils which partly bridge the gap between echinoderms and chordates. Evidence suggests that this group included the ancestors of the vertebrates. Its members are traditionally regarded as primitive echinoderms, but are better seen as primitive chordates with echinoderm affinities. They form a basal subphylum of chordates-the Calcichordata Jefferies 1967. The Calcichordata, in accordance with an early suggestion by Gislén, are probably ancestral to all living chordates. The new calcichordate is named Reticulocarpos hanusi gen et sp. nov. It comes from the Lower Ordovician ?árka Formation (Llanvirn) of ?árka near Prague, Czechoslovakia and is placed in the family Amygdalothecidae Ubaghs 1970. It is important because of its position in the Calcichordata. This group is divided into two very different orders–the Cornuta and the Mitrata. The Cornuta are the more primitive order and gave rise to the Mitrata, which had the structure of giant, calcite-plated tunicate tadpoles. Many features show that the new species is a very advanced cornute, closely related to the stock that gave rise to the mitrates. For this reason it is important in the general history of the chordates, since some primitive mitrate was probably the latest common ancestor of the living chordate subphyla i.e. of tunicates, of amphioxus and its allies and of the vertebrates. Being a mitrate-like cornute, the new species allows the cornutes and mitrates to be compared more confidently than before. Four results are especially important. Firstly it is likely that the stem (=tail) of mitrates is equivalent only to the anterior part of the stem of cornutes. This is significant, because traditional views as to which was the upper surface in mitrates have been based on stem homologies now seen as false. Secondly Reticulocarpos hanusi is adapted to stay up on very soft mud, using only the strength of the mud for support. The mitrates, on the other hand, supported themselves on soft mud by a much more reliable method resembling buoyancy. Thirdly, the new form had paired transpharyngeal eyes which are otherwise known only in mitrates, and which are the earliest type of paired eyes in chordates. Fourthly, it becomes possible to homologize the thecal plates of cornutes with those of mitrates. Reticulocarpos hanusi represents an important phase in chordate evolution dominated by the necessity of staying up on mud by a very precarious method. During this phase many pre-adaptations for swimming were acquired. Primitive mitrates, descended from a very similar form, were probably the first chordates that could swim.  相似文献   
4.
Botanists are an overlooked group of informants in ethnobotanical studies. The aim of this study was to assess their potential as sources of original ethnobotanical information. Wild food plants remembered by Polish botanists from their childhood were freelisted by 71 botanists. The results were compared with several ethnobotanical studies: three from the 21st century and one from the mid‐20th century. The botanists listed 123 species (mean of 9.3 species per individual). Although the average number of personal freelists was slightly lower for botanists than for local key informants in two of the other studies (11 and 13, respectively), the total list of species was longer than in any other Polish ethnobotanical study. Two of the ethnobotanical studies supplied richer material on past famine plants, whereas the botanists mentioned many alien plants and plants from urban habitats not mentioned in the ethnographical study. It can be concluded that botanists are possibly the best source of information for studies of contemporary or new uses of plants, but are inadequate for uses that are dying out. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 334–343.  相似文献   
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6.
We studied hybridization between the diploid Centaurea pseudophrygia and the tetraploid C. jacea by performing crossing experiments and screening natural populations using flow cytometry. The experiments confirm that the studied species exhibit strong reproductive isolation. Interspecific hybrids were formed at a low frequency, including triploids (originating from reduced gametes) and tetraploids (involving unreduced gametes of the diploids). In contrast, hybrids were almost absent among seeds and adult plants of natural mixed populations and among the offspring from experimental pollinations with a mixture of pollen of both ploidy levels. We found that mixed pollination is an important mechanism for preventing hybridization between plants of different ploidy levels and sustaining the reproduction of the tetraploids. A mentor effect (induced selfing in the presence of pollen of different ploidy levels) was observed in both diploids and tetraploids, reinforcing the reproductive isolation between cytotypes. Higher ploidy levels (pentaploid, hexaploid) involving unreduced gametes of the tetraploid species were identified. Notably, pentaploids were discovered for the first time in Centaurea sect. Jacea. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 93–106.  相似文献   
7.
The habitat association approach has been increasingly used in ecology to resolve problems in wildlife conservation and management. One problem related to habitat association studies is that they are restricted to small geographical areas within a species' range, and thus they are applicable to only a limited set of environmental conditions utilized by the species. In addition, very few studies address why the preference for specific habitat components may be adaptive for the species in question. The objective of this study was to examine how consideration of populations of a species from two dramatically different environments affects the results of habitat association modelling for a ground-nesting passerine, the Rock Bunting Emberiza cia . At a regional scale, a trend to defending breeding habitat patches with relatively higher stone cover was confined to birds from a temperate region in Slovakia. In contrast, in a semi-arid region in southeastern Spain, Rock Buntings preferred to use breeding habitat patches that had relatively higher grass cover. Combining data from both regions, breeding Rock Buntings showed a general pattern of using habitat patches close to hedges, with low bush cover, high ditch density and a steep slope. Whereas regional habitat association models appear to be sensitive to the particularities of the breeding environment, our study suggests that Rock Bunting breeding habitat association is constrained by the adults' tactics to protect themselves against predators. Although the birds prefer to nest in patches of low vegetation, the better to see nearby predators, these patches are ideally close to taller vegetation that can be used to provide cover when evading predators, and they are also of a rugged profile that helps the birds to approach and leave the nest stealthily.  相似文献   
8.
A revision of the holotype of Triplosoba pulchella (Brongniart, 1883), the ‘oldest mayfly’, provides evidence for new attribution to Palaeodictyopterida sensu Bechly. New character states derived from the venation pattern, namely the basal connection of the median anterior with the radius and radius posterior in the forewing, the median anterior remote from the radius posterior and basally fused with the median posterior in the hindwing, and a strong costal margin formed by two connected or fused veins with a series of small spines (costa and subcosta anterior), support an ordinal placement of Triplosoba into Palaeodictyopterida (inclusive of Diphanopterodea sensu Bechly) versus Ephemeroptera as supposed by previous authors. It shares with Diaphanopterodea a potential synapomorphy in the presence of long curved connections between the three stems of the radius, media, and cubitus in the basal part of the forewing, a character not present in other groups of Palaeodictyopterida.  相似文献   
9.
10.
Sexual size dimorphism (SSD) is a widespread phenomenon in different animal taxa, including the subfamily of goats and sheep (Caprinae), which belongs to the most dimorphic mammalian groups. Rensch's rule describes the pattern of SSD, claiming that larger species generally exhibits higher male to female body size ratio. Agreement with Rensch's rule is manifested by slope of the allometric relationship between male and female body size exceeding one. To test this rule, we analysed the data available in the literature on adult body mass of males and females in domestic goat and sheep breeds (169 and 303, respectively) and 37 wild species/subspecies of the subfamily Caprinae. According to the current phylogenetical hypotheses, there are six distinct monophyletic groups with different levels of SSD (expressed as M/F): (1) wild goats (1.83); (2) wild sheep (1.67); (3) non‐European chamoises, including Ovibos moschatus (1.18); (4) European chamoises (1.27); (5) Budorcas taxicolor (1.01); and (6) Pantholops hodgsonii (1.65). Domestication has led to a remarkable decline in SSD of both domestic goats (1.36) and sheep (1.41). The highest regression slope of the relationship between male and female body size is that estimated for wild goats (1.32), followed by wild sheep (1.24), non‐European chamoises (1.14), domestic sheep (1.13), and domestic goats (1.10). Nevertheless, only the last two values are statistically different from one and thus corroborate Rensch's rule. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98 , 872–883.  相似文献   
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