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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   
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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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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   
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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   
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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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The biogeochemistry of Ca, Mg, K, and Nawere investigated in two forested catchments in theCzech Republic, one underlain by leucogranite, theother by serpentinite. High weathering rates at theserpentinite site at Pluhv Bor resultedin Mg2+ as the dominant cation on the soilexchange complex and in drainage water. Other basiccations (Ca2+, K+, Na+) showedrelatively low concentrations and outflow instreamwater. The catchment exhibited high basesaturation in mineral soils (>70%), and nearneutral soil and stream pH, despite elevated inputsof acidic deposition. Slow growth of Norway spruceat Pluhv Bor may be caused by K deficiency, Mgoversupply and/or Ni toxicity. In contrast, thegranitic site at Lysina showed low concentrations ofbasic cations on the soil exchange complex and instreamwater. Soil and drainage water at Lysina werehighly impacted by acidic deposition. Soil pH wasextremely acidic (<4.5) throughout the soilprofile, and the base saturation of the mineral soilwas very low (<5%). Supplies of basic cationsfrom atmospheric deposition and soil processes wereless than inputs of SO2- 4 on anequivalence basis, resulting in low pH and highconcentrations of total Al in drainage water. Needle yellowing in Norway spruce was possibly theresult of Mg deficiency at Lysina. Because of theirextremely different lithologies, these catchmentsserve as valuable end-members of ecosystemsensitivity to elevated levels of acidicdeposition.  相似文献   
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The closely related conodont species Idiognathoides noduliferus and Idiognathoides sulcatus underwent morphologic diversification in the lower Morrowan (Lower Pennsylvanian). The expanding range of variation of the two progenitor species overlapped, producing a completely intergraded morphologic-continuum. Non-intergradation and taxonomic differentiation at stratigraphically higher levels in the Morrowan demonstrate that certain morphotypes within the continuum bore the potential of becoming descendant species. The descendant species include Idiognathoides sinuatus, Idiognathoides macer, and Gnathodus bassleri symmetricus, Conventional systematic techniques are inadequate to depict the morphologic complexity and evolution shown by this example.  相似文献   
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We performed a phylogenetic analysis focused on the hydrophiloid family Helophoridae (Coleoptera: Polyphaga) in order to test the phylogenetic position of selected Mesozoic fossils assigned to the Hydrophiloidea. The analysis is based on 92 characters of larvae and adults, and includes all extant subgenera of Helophorus and representatives of all other extant hydrophiloid families. Based on this analysis, we provide additional evidence for the monophyly of the helophorid lineage containing the families Helophoridae, Georissidae and Epimetopidae, as well as the first hypothesis on the phylogenetic relationships within Helophorus, revealing three main clades: Lihelophorus, Rhopalohelophorus and the clade of sculptured small subgenera; the subgenera Helophorus s.str., Gephelophorus, Trichohelophorus and Transithelophorus are recognized as paraphyletic or polyphyletic. Inclusion of fossil species in the analysis reveals the Mesozoic genera Hydrophilopsia Ponomarenko, Laetopsia Fiká?ek et al. (adult forms) and Cretotaenia Ponomarenko (larval form) as basal extinct clades of the helophorid lineage, the former genus Mesosperchus Ponomarenko as containing probable stem taxa of Helophorus and the former genus Mesohelophorus Ponomarenko as a member of the Helophorus clade containing extant sculptured subgenera. The extant subgenus Thaumhelophorus syn.nov. is synonymized with Rhopalohelophorus. Our results show that the family Helophoridae may be dated back to the late Jurassic (c. 150 Ma) and the extant clades of Helophorus back to the Early Cretaceous (c. 136 Ma). The basal groups of Helophorus and the supposed basal extinct lineages of the helophorid lineages are shown to be aquatic as adults. A single origin of trichobothria and ventral hydrophobic pubescence in the common ancestor of the Hydrophiloidea is hypothesized, indicating ancestral aquatic habits in the adult stage for the whole Hydrophiloidea.  相似文献   
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