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101.
LISE COMTE LAËTITIA BUISSON MARTIN DAUFRESNE GAËL GRENOUILLET 《Freshwater Biology》2013,58(4):625-639
1. Climate change could be one of the main threats faced by aquatic ecosystems and freshwater biodiversity. Improved understanding, monitoring and forecasting of its effects are thus crucial for researchers, policy makers and biodiversity managers. 2. Here, we provide a review and some meta‐analyses of the literature reporting both observed and predicted climate‐induced effects on the distribution of freshwater fish. After reviewing three decades of research, we summarise how methods in assessing the effects of climate change have evolved, and whether current knowledge is geographically or taxonomically biased. We conducted multispecies qualitative and quantitative analyses to find out whether the observed responses of freshwater fish to recent changes in climate are consistent with those predicted under future climate scenarios. 3. We highlight the fact that, in recent years, freshwater fish distributions have already been affected by contemporary climate change in ways consistent with anticipated responses under future climate change scenarios: the range of most cold‐water species could be reduced or shift to higher altitude or latitude, whereas that of cool‐ and warm‐water species could expand or contract. 4. Most evidence about the effects of climate change is underpinned by the large number of studies devoted to cold‐water fish species (mainly salmonids). Our knowledge is still incomplete, however, particularly due to taxonomic and geographic biases. 5. Observed and expected responses are well correlated among families, suggesting that model predictions are supported by empirical evidence. The observed effects are of greater magnitude and show higher variability than the predicted effects, however, indicating that other drivers of changes may be interacting with climate and seriously affecting freshwater fish. 6. Finally, we suggest avenues of research required to address current gaps in what we know about the climate‐induced effects on freshwater fish distribution, including (i) the need for more long‐term data analyses, (ii) the assessment of climate‐induced effects at higher levels of organisation (e.g. assemblages), (iii) methodological improvements (e.g. accounting for uncertainty among projections and species’ dispersal abilities, combining both distributional and empirical approaches and including multiple non‐climatic stressors) and (iv) systematic confrontation of observed versus predicted effects across multi‐species assemblages and at several levels of biological organisation (i.e. populations and assemblages). 相似文献
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D.W. Brammer C.M. O'Rourke LA Heath C.E. Chrlsp G.K. Peter G.L. Hofing 《Journal of medical primatology》1995,24(4):231-235
Abstract: This report documents asymptomatic infections of Mycobacterium kansasii in four of five tuberculin positive squirrel monkeys (Saimiri sciureus sciureus). The mycobacterial DNA amplified by polymerase chain reaction (PCR) from a bronchial lymph node had no affinity for the species specific probes of M. tuberculosis, M. avium, and M. intracellular, thus allowing the presumptive diagnosis of an atypical mycobacterial infection. Infection by Mycobacterium kansasii was confirmed by culture of bronchial lymph nodes from three monkeys. The source of the infection was never identified. 相似文献
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JESÚS MANZANILLA ENRIQUE LA MARCA MARIO GARCÍA-PARÍS 《Biological journal of the Linnean Society. Linnean Society of London》2009,97(1):185-199
We used partial sequences of mitochondrial 16S and cytochrome oxidase I genes to perform a phylogenetic study of collared frogs (Anura: Aromobatidae: Mannophryne ), a genus endemic to Venezuela and the islands of Trinidad and Tobago. We analysed 1.2 kb from 13 of the 15 described species of Mannophryne . Maximum parsimony, maximum likelihood and Bayesian analyses support the monophyly of Mannophryne . Mannophryne consists of three deeply differentiated clades that split from each other in a relatively short period of time. The diversification of Mannophryne occurred well before the glacial-interglacial periods of the Quaternary. Our data support the taxonomic validity of M. olmonae , a species endemic to Tobago Island. Mannophryne olmonae is more closely related to the continental species Mannophryne riveroi than to the Trinidad island endemic Mannophryne trinitatis . As in most tropical clades of frogs, molecular evidence indicates that species richness in Mannophryne is largely underestimated and, consequently, current priorities for conservation are inadequate. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 185–199. 相似文献
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Antonio Hernández-Matías Joan Real Roger Pradel 《The Journal of wildlife management》2011,75(4):856-866
Survival is a key life-history trait in animals. However, most methods of survival estimation require substantial human and economic investment in the long term, particularly in species occurring in low densities, the case of most endangered species. An alternative to traditional recapture (CR) methods is estimation of adult survival based indirectly on either age ratios (AGR) or turnover rates (TOR) in territorial species. These 2 methods are applicable to bird species in which recruited individuals enter into the breeding population whilst still exhibiting the external traits that distinguish those animals from experienced adults. The main advantages of these methods are that survival can be easily estimated for all monitored individuals after just 1 or 2 breeding seasons and that disturbance to the species is minimized. The main constraints of indirect methods are that the assumptions are more restrictive than in CR methods, and survival estimates, although comparable between sites and years, may be biased. We used data from a long-term monitoring survey of 2 populations of the endangered Bonelli's eagle (Aquila fasciata), one in Catalonia (NE Spain) and the other in Provence and Languedoc-Roussillon (SE France). We evaluated survival estimates using the AGR and TOR methods and compared them with CR methods and provide suitable corrections for refining survival estimates based on indirect methods. In Catalonia (2002–2008), survival was estimated at 0.84 by CR methods (SE = 0.047; n = 25 radio tagged eagles), at 0.86 by the corrected AGR method (SE = 0.011; n = 558 bird * year), and at 0.86 by the corrected TOR method (SE = 0.022; n = 547 bird * year). In France (1999–2008), survival was estimated at 0.88 by CR methods (SE = 0.040; n = 45 darvic banded eagles), at 0.87 by the corrected AGR method (SE = 0.015; n = 443 bird * year), and at 0.87 by the corrected TOR method (SE = 0.015; n = 438 bird * year). All analyses suggest that females survive better than males and that individuals from the French population survive better than individuals from the Catalan population. We conclude that indirect methods, which should not be regarded as a substitute of CR methods, will allow wildlife managers and researchers to estimate accurately adult survival in a territorial species over a short period of time and to monitor survival across populations over large geographic ranges and over time. © 2011 The Wildlife Society. 相似文献
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Five proteins having molecular masses of 90, 67, 37, 36, and 32 kDa (p90, p67, p37, p36, and p32, respectively) were identified in the particulate fractions of pig brain cortex and pig spinal cord prepared in the presence of 0.2 mM Ca2+ and further purified using a protocol previously described for the purification of calpactins. Proteins p90, p37, and p36 are related to annexins I and II. Annexin II, represented by p90, is found as an heterotetramer, composed of two heavy chains of 36 kDa and two light chains of 11 kDa, and as a monomer of 36 kDa. Protein p37, which differs immunologically from p36, is a monomer and could be related to annexin I. All three proteins are Ca(2+)-dependent phospholipid- and F-actin-binding proteins; they are phosphorylated on a serine and on a tyrosine residue by protein kinases associated with synaptic plasma membranes. Purified p36 monomer and p36 heterotetramer proteins bind to actin at millimolar Ca2+ concentrations. The stoichiometry of p36 binding to F-actin at saturation is 1:2, corresponding to one tetramer or monomer of calpactin for two actin monomers (KD, 3 x 10(-6) M). Synaptic plasma membranes supplemented with the monomeric or tetrameric forms of p36 phosphorylate the proteins on a serine residue. The monomer is phosphorylated on a serine residue by a Ca(2+)-independent protein kinase, whereas the heterotetramer is phosphorylated on a serine residue and a tyrosine residue by Ca(2+)-dependent protein kinases. Antibodies to brain p37 and p36 together with antibodies to lymphocytes lipocortins 1 and 2 were used to follow the distribution of these proteins in nervous tissues. Polypeptides of 37, 34, and 36 kDa cross-react with these antibodies. Anti-p37 and antilipocortin 1 cross-react on the same 37- and 34-kDa polypeptides; anti-p36 and antilipocortin 2 cross-react only on the 36-kDa polypeptides. 相似文献
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