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HENDRIK-JAN MEGENS RIENK DE JONG KONRAD FIEDLER 《Biological journal of the Linnean Society. Linnean Society of London》2005,84(2):225-241
The Oriental butterfly genus Arhopala is by far the most species‐rich genus within the subfamily Theclinae. We investigated whether biotic interactions with larval host plants or ants are phylogenetically constrained in the evolutionary history of Arhopala, by collating available information on the ecology of Arhopala from the literature as well as from personal observations, and analysing and interpreting these data rigorously in a phylogenetic context. Larvae of all species in the sister‐group of Arhopala and Flos feed on Fabaceae. However, the predominant feeding preference of Arhopala s.l., with the exception of a particular monophyletic and species‐rich group, called ‘Group A’, appears to be centred on Fagaceae, with additional records of Dipterocarpaceae feeding. The preference for Fagaceae has strong phylogenetic inertia, as indicated by T‐PTP tests designed to test for phylogenetic signal. Adding all available life‐history data, using the phylogeny presented before as scaffolding, further increased the phylogenetic signal in host plant data. Feeding on Fabaceae (mainly in the outgroup) and Euphorbiaceae also showed significant phylogenetic signal, but feeding on Dipterocarpaceae did not and was found scattered across the phylogeny. Except for the Dipterocarpaceae, phylogenetic signal in feeding preferences was very clear, even despite uneven taxon sampling and apparent lability in host plant use. Ant association also demonstrated historical constraint, but based on the phylogenetic hypothesis presented here it was not clear whether increased ant association intimacy emerged independently various times in Group A, as well as in several basal groups. Our finding of distinct phylogenetic patterns in the host plant and to a lesser degree in ant association data contradicts the hypothesis that life‐history traits are very labile in the Lycaenidae. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 84 , 225–241. 相似文献
94.
PAULA M. DE OMENA MÔNICA F. KERSCH‐BECKER PABLO A. P. ANTIQUEIRA TIAGO N. BERNABÉ SANDRA BENAVIDES‐GORDILLO FÁTIMA C. RECALDE CAMILA VIEIRA GUSTAVO H. MIGLIORINI GUSTAVO Q. ROMERO 《Ecological Entomology》2018,43(3):389-393
1. A key challenge in the study of mutualistic interactions is understanding sources of variation that strengthen or weaken these interactions. In spider–plant mutualisms, spiders benefit plants by improving plant nutrition and protecting plants from herbivory. Although the benefits of plants to spider growth and survival are often claimed, they are rarely demonstrated. 2. In this study, empirical evidence is provided that bromeliads (Bromelia balansae, Bromeliaceae) are essential for the resilience of the mutualistic bromeliad‐living jumping spider populations (Psecas chapoda, Salticidae) after a fire event, sheltering spiders from the heat of the flames. 3. Spider populations were compared before and after a natural fire event and it was shown that spiders of different ages survived the fire. The survival of such individuals allowed the population of P. chapoda spiders to recover rapidly, returning to pre‐fire levels in 5 months. 4. Bromeliads reduced the susceptibility of P. chapoda spiders to burning, and this mutualistic relationship contributed to the resilience of the spider population after a fire event. It is suggested that frequent fires in fire‐prone landscapes may have strengthened this spider–plant relationship, contributing to the maintenance and evolution of this association. 相似文献
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96.
Simple scaling of photosynthesis from leaves to canopies without the errors of big-leaf models 总被引:24,自引:0,他引:24
In big-leaf models of canopy photosynthesis, the Rubisco activity per unit ground area is taken as the sum of activities per unit leaf area within the canopy, and electron transport capacity is similarly summed. Such models overestimate rates of photosynthesis and require empirical curvature factors in the response to irradiance. We show that, with any distribution of leaf nitrogen within the canopy (including optimal), the required curvature factors are not constant but vary with canopy leaf area index and leaf nitrogen content. We further show that the underlying reason is the difference between the time-averaged and instantaneous distributions of absorbed irradiance, caused by penetration of sunflecks and the range of leaf angles in canopies. These errors are avoided in models that treat the canopy in terms of a number of layers – the multi-layer models. We present an alternative to the multi-layer model: by separately integrating the sunlit and shaded leaf fractions of the canopy, a single layered sun/shade model is obtained, which is as accurate and simpler. The model is a scaled version of a leaf model as distinct from an integrative approach. 相似文献
97.
CECILE POMPORT-CASTILLON BERNARD ROMESTAND JOHAN F. DE JONCKHEERE 《The Journal of eukaryotic microbiology》1997,44(6):540-544
ABSTRACT. The SSUrDNA and the ITS of different microsporidia from eight fishes, four insects and a shrimp were amplified and digested with restriction enzymes. The generated riboprints suggest a close evolutionary relationship between Glugea americanus and Spraguea lophii suggesting that Glugea americanus should be renamed Spraguea americanus and that the tissue infected and host origin should be considered of greater taxonomic importance for defining a genus than previously considered. Phylogenetic analysis of the riboprints demonstrates an unidentified microsporidium from a bumper fish ( Chloroscombrus chrysurus ) is related although not identical to Microgemma oviodea , a parasite from red band fish. We were also able to distinguish between Glugea anomala and Glugea atherinae and Glugea stephani but were not able to differenciate among the latter two. Insects isolates, Nosema costelytrae, N. bombycis, N. trichoplusiae, Nosema sp. and a shrimp isolate, Agmasoma penaei , are not related to the fish isolates. 相似文献
98.
MÁRCIA FERNANDES DE AQUINO SANTOS JOSÉ RICARDO M. MERMUDES VERA MARIA MEDINA DA FONSECA 《Palaeontology》2011,54(4):807-814
Abstract: A specimen of Curculionidae (Curculioninae) is described as Arariperhinus monnei gen. et sp. nov. The specimen is preserved on a laminated limestone sample of the Crato Formation (Santana Group), Lower Cretaceous (Aptian–Albian), and was collected from a quarry near Nova Olinda, Chapada do Araripe, State of Ceará, Brazil. The genus is placed in the subfamily Curculioninae because of its strongly convex body and relatively slender rostrum, but mainly by its rounded eyes and lack of a prosternal sulcus and tibial spurs. The very prominent eyes in lateral view, a cylindrical rostrum and a straight posterior margin of ventrite II are strong indications that this fossil belongs to the tribe Anthonomini. However, the claws, which would resolve the exact placement of this fossil, are poorly preserved. Arariperhinus monnei gen. et sp. nov. is distinguishable by the combination of several characters and the first record of the family Curculionidae in the Santana Group; it is the oldest record of a member of the subfamily Curculioninae. 相似文献
99.
REBECCA M. Harman MEGAN K. HE SHENG ZHANG GERLINDE R. VAN DE WALLE 《Cytotherapy》2018,20(8):1061-1076
Background
Impaired cutaneous wound healing is common in humans, and treatments are often ineffective. Based on the significant emotional and economic burden of impaired wound healing, innovative therapies are needed. The potential of mesenchymal stromal cell (MSC)–secreted factors to treat cutaneous wounds is an active area of research that is in need of refinement before effective clinical trials can be initiated. The aims of the present study were to (i) study which MSC-secreted factors stimulate dermal fibroblast (DF) migration in vitro and (ii) evaluate the potential of these factors to promote wound healing in vivo.Methods
To this end, MSCs were isolated from the peripheral blood of healthy horses, a physiologically relevant large animal model appropriate for translational wound-healing studies. Conditioned medium (CM) from cultured equine MSCs was analyzed using liquid chromatography-mass spectrophotometry (LC-MS/MS) to identify secreted proteins of interest. Double-stranded RNA-mediated interference (RNAi) was used to silence the genes encoding selected proteins, and the effects of CM from these transfected MSCs on migration of cultured equine DF cells in vitro and full-thickness wounds in mice were evaluated.Results
We found that MSC-derived plasminogen activator inhibitor-1 (PAI-1) and tenascin-C significantly increased DF migration in vitro and improved wound healing in vivo by decreasing time to wound closure.Discussion
These results suggest that in a complex wound environment, MSC-secreted factors PAI-1 and tenascin-C contribute to the positive effect of therapeutically applied MSC CM on wound healing. 相似文献100.