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McInnes L Baker WJ Barraclough TG Dasmahapatra KK Goswami A Harmon LJ Morlon H Purvis A Rosindell J Thomas GH Turvey ST Phillimore AB 《Biology letters》2011,7(5):644-646
On 9 March, over 150 biologists gathered in London for the Centre for Ecology and Evolution spring symposium, 'Integrating Ecology into Macroevolutionary Research'. The event brought together researchers from London-based institutions alongside others from across the UK, Europe and North America for a day of talks. The meeting highlighted methodological advances and recent analyses of exemplar datasets focusing on the exploration of the role of ecological processes in shaping macroevolutionary patterns. 相似文献
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MIREILLE OKASSA SERGE KREITER SABINE GUICHOU MARIE‐STÉPHANE TIXIER 《Biological journal of the Linnean Society. Linnean Society of London》2011,104(2):393-406
Neoseiulus californicus (McGregor) is a natural enemy of pest mites used worldwide in many crops. Its correct identification is thus essential to ensure biological control success. The present study aimed to characterize molecular and morphological intraspecific variations for assisting in the diagnosis of the species and to build baseline information about expected variations within a commercially important phytoseiid species. Morphological and molecular [12S rRNA, cytochrome b mitochondrial (mt)DNA, and internal transcribed spacer] analyses were carried out on fourteen populations collected worldwide and on one mass‐reared strain. The genetic distances between the specimens of N. californicus and another related species were high and no overlap was observed, sustaining the reliability of such molecular methods for assisting a specific diagnosis. Furthermore, the genetic distances between populations of N. californicus were very low and overlap between intra‐ and interpopulations distances was observed, except for two populations collected in France (Marsillargues and Midi‐Pyrénées). The high mitochondrial differentiation between these two latter populations and the others questions their specific status: do they belong to the species N. californicus or to another cryptic species? However, using nuclear DNA marker analyses, no distinct differences were observed. Furthermore, even if significant morphological differences were observed between the populations, these differences were very small and the standard errors within each population were very low. We thus concluded that all the populations studied belong to the species N. californicus, despite unexpected high mitochondrial variations. The present study thus displays the importance of an integrative taxonomic approach for avoiding misidentifications. A discussion on morphological and mtDNA variations in relation to diagnostic reliability is developped. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 393–406. 相似文献
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SOIZIC MORIN ANNE‐SOPHIE LAMBERT JOAN ARTIGAS MARINA COQUERY STÉPHANE PESCE 《Freshwater Biology》2012,57(8):1658-1666
1. The impact of immigration on the recovery of diatom assemblages after chronic exposure to copper was investigated in laboratory microcosms. 2. We examined the recovery trajectories of copper‐contaminated biofilms after reducing copper stress and with or without the possibility of immigration from unimpaired communities. 3. The biofilms mixed with unimpaired communities returned to a ‘control’ assemblage structure within 6 weeks, with recovery patterns depending on the endpoint considered (i.e. 2 weeks for relative abundances of diatom species but 6 weeks for total diatom biomass). In contrast, no recovery was observed in assemblages placed under control conditions without external immigrants. 4. Immigration has important effects on the recovery of quantitative and qualitative characteristics of biofilms. 相似文献
86.
Innate immunity mediated by TLR5 as a novel antiinflammatory target for cystic fibrosis lung disease
Blohmke CJ Victor RE Hirschfeld AF Elias IM Hancock DG Lane CR Davidson AG Wilcox PG Smith KD Overhage J Hancock RE Turvey SE 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(11):7764-7773
Novel therapies to target lung inflammation are predicted to improve the lives of people with cystic fibrosis (CF) but specific antiinflammatory targets have not been identified. The goal of this study was to establish whether TLR5 signaling is the key molecular pathway mediating lung inflammation in CF, and to determine whether strategies to inhibit TLR5 can reduce the damaging inflammatory response. The innate immune responses were analyzed in both airway epithelial cells and primary PBMCs from CF patients and matched controls. Additionally, 151 clinical isolates of Pseudomonas aeruginosa from CF patients were assessed for motility and capacity to activate TLR5. Blood and airway cells from CF patients produced significantly more proinflammatory cytokine than did control cells following exposure to the CF pathogens P. aeruginosa and Burkholderia cepacia complex (p < 0.001). Stimulation with pure TLR ligands demonstrated that TLR signaling appears to mediate the excessive cytokine production occurring in CF. Using complementary approaches involving both neutralizing Ab targeting TLR5 and flagellin-deficient bacteria, we established that inhibition of TLR5 abolished the damaging inflammatory response generated by CF airway cells following exposure to P. aeruginosa (p < 0.01). The potential therapeutic value of TLR5 inhibition was further supported by our demonstration that 75% of clinical isolates of P. aeruginosa retained TLR5 activating capacity during chronic CF lung infection. These studies identify the innate immune receptor TLR5 as a novel antiinflammatory target for reducing damaging lung inflammation in CF. 相似文献
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DIANA H. WALL MARK A. BRADFORD MARK G. ST. JOHN JOHN A. TROFYMOW VALERIE BEHAN‐PELLETIER DAVID E. BIGNELL J. MARK DANGERFIELD WILLIAM J. PARTON JOSEF RUSEK WINFRIED VOIGT VOLKMAR WOLTERS HOLLEY ZADEH GARDEL FRED O. AYUKE RICHARD BASHFORD OLGA I. BELJAKOVA PATRICK J. BOHLEN ALAIN BRAUMAN STEPHEN FLEMMING JOH R. HENSCHEL DAN L. JOHNSON T. HEFIN JONES MARCELA KOVAROVA J. MARTY KRANABETTER LES KUTNY KUO‐CHUAN LIN MOHAMED MARYATI DOMINIQUE MASSE ANDREI POKARZHEVSKII HOMATHEVI RAHMAN MILLOR G. SABARÁ JOERG‐ALFRED SALAMON MICHAEL J. SWIFT AMANDA VARELA HERALDO L. VASCONCELOS DON WHITE XIAOMING ZOU 《Global Change Biology》2008,14(11):2661-2677
Climate and litter quality are primary drivers of terrestrial decomposition and, based on evidence from multisite experiments at regional and global scales, are universally factored into global decomposition models. In contrast, soil animals are considered key regulators of decomposition at local scales but their role at larger scales is unresolved. Soil animals are consequently excluded from global models of organic mineralization processes. Incomplete assessment of the roles of soil animals stems from the difficulties of manipulating invertebrate animals experimentally across large geographic gradients. This is compounded by deficient or inconsistent taxonomy. We report a global decomposition experiment to assess the importance of soil animals in C mineralization, in which a common grass litter substrate was exposed to natural decomposition in either control or reduced animal treatments across 30 sites distributed from 43°S to 68°N on six continents. Animals in the mesofaunal size range were recovered from the litter by Tullgren extraction and identified to common specifications, mostly at the ordinal level. The design of the trials enabled faunal contribution to be evaluated against abiotic parameters between sites. Soil animals increase decomposition rates in temperate and wet tropical climates, but have neutral effects where temperature or moisture constrain biological activity. Our findings highlight that faunal influences on decomposition are dependent on prevailing climatic conditions. We conclude that (1) inclusion of soil animals will improve the predictive capabilities of region‐ or biome‐scale decomposition models, (2) soil animal influences on decomposition are important at the regional scale when attempting to predict global change scenarios, and (3) the statistical relationship between decomposition rates and climate, at the global scale, is robust against changes in soil faunal abundance and diversity. 相似文献
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The remarkable elongated upper canines of extinct sabretoothed carnivorous mammals have been the subject of considerable speculation on their adaptive function, but the absence of living analogues prevents any direct inference about their evolution. We analysed scaling relationships of the upper canines of 20 sabretoothed feliform carnivores (Nimravidae, Barbourofelidae, Machairodontinae), representing both dirk-toothed and scimitar-toothed sabretooth ecomorphs, and 33 non-sabretoothed felids in relation to body size in order to characterize and identify the evolutionary processes driving their development, using the scaling relationships of carnassial teeth in both groups as a control. Carnassials display isometric allometry in both sabretooths and non-sabretooths, supporting their close relationship with meat-slicing, whereas the upper canines of both groups display positive allometry with body size. Whereas there is no statistical difference in allometry of upper canine height between dirk-toothed and scimitar-toothed sabretooth ecomorphs, the significantly stronger positive allometry of upper canine height shown by sabretooths as a whole compared to non-sabretooths reveals that different processes drove canine evolution in these groups. Although sabretoothed canines must still have been effective for prey capture and processing by hypercarnivorous predators, canine morphology in these extinct carnivores was likely to have been driven to a greater extent by sexual selection than in non-sabretooths. Scaling relationships therefore indicate the probable importance of sexual selection in the evolution of the hypertrophied sabretooth anterior dentition. 相似文献