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61.
《L'Anthropologie》2015,119(1):1-37
The most recent synthesis on the mortuary practices in the Middle Neolithic in Mediterranean France was published more than a decade ago. We propose to characterize those gestures focusing on the funerary nature of some inhumations discovered on domestic settlement. Two types of structures are distinguished. The first is composed of pits which function is exclusively related to funerary body or cremated bones deposit. Their features enable to consider that they are tombs. The domestic pits used as bodies or bones deposition constitute the second type. They are the most frequent in our corpus. Some of them display many features of the regular tombs but the configurations of most of those circular pits are difficult to interpret. Some alternative hypotheses are proposed to explain these particular body depositions. 相似文献
62.
Blood and cloacal swab sampling for avian influenza monitoring has no effect on survival rates of free‐ranging ducks
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Matthieu Guillemain Jocelyn Champagnon Marie‐Lucile Gourlay‐Larour Francois Cavallo Anne‐Laure Brochet Jean Hars Gregoire Massez Thierry George Pierre‐Yves Perroi Veronique Jestin Alain Caizergues 《Ibis》2015,157(4):743-753
Concerns about the spread of avian influenza viruses (AIVs) have led to cloacal swab sampling of hundreds of thousands of birds worldwide as part of AIV surveillance schemes, but the effects of cloacal swabbing have not been adequately evaluated. We tested for differences between swabbed, swabbed and bled, and non‐sampled wild ducks in terms of live re‐encounter and dead recoveries for Common Pochard Aythya ferina and Tufted Duck Aythya fuligula, and also determined re‐encounter and recovery rates for Mallard Anas platyrhynchos and Common Teal Anas crecca. No effects of sampling methods were detected, except in Teal. Re‐encounter rates were lower in sampled Teal than in controls, with annual re‐encounter probabilities being 25% and 35% lower in males and females, respectively. Teal possibly left or avoided sampling sites, or sought sites where they were less detectable after sampling. In general, no deleterious effects were found, suggesting that cloacal swabbing and blood sampling are suitable methods for conducting AIV surveillance in ducks. 相似文献
63.
从贵州鼠尾草95%乙醇提取物分离得到8个化合物,通过理化性质及波谱方法分别鉴定为正三十三烷(1),十二烷酸十四烷酯(2),β-谷甾醇(3),胡萝卜苷(4),乌苏酸(5),2 a,3β-二羟基乌苏酸(6),白桦酸(7)和迷迭香酸(8)。以上化合物均首次从该植物中分离得到。 相似文献
64.
Even if European river management and restoration are largely supported by the use of reliable tools, these tools are most often “generalist” and provide only initial leads of alteration sources. Acknowledging that young-of-the-year (YOY) fish assemblages are highly dependent on riverine habitat conditions, the development of a YOY-based tool might be very useful or even essential in the design and implementation of conservation or restoration plan of large rivers, in measuring more straight-forward the losses and gains of hydro-ecological functionalities. In the past 20 years, new modeling techniques have emerged from a growing sophistication of statistical model applied to ecology. “Machine learning methods” (ML) are now recognized as holding great promise for the advancement of understanding and prediction of ecological phenomena. The aim of this work was to select the appropriate statistical technique to model YOY assemblages according to different meso-scale habitat variables that are meaningful to planners. To do this, two “Machine Learning” methods, Classification and Regression Trees (CART) and Boosted Regression Trees (BRT), were compared to Generalized Linear Models (GLM). We modeled the occurrence of 9 species from the Seine River basin (France) in order to compare models abilities to accurately predict the presence and absence of each species. BRT appeared to be the best technique for modeling 0+ fish occurrences in our dataset. 相似文献
65.
A new species of the thermophylic Tethyan relict prawn Typhlatya is described from two anchialine caves near Perpignan (southern France). The new species is closely related to a congener known only from a freshwater cave at Castellón (eastern Spain), about 400 km to the south-west, differing apparently only in the size and shape of the rostrum and the armature of the dactylus of the fifth pereiopod. Based on palaeogeographical evidence and assuming a sister-group relationship between both species, we suggest that their common ancestor could not be older than early Pliocene in age, and that it was already a stygobiont taxon adapted to live in shallow-water marine crevicular habitats. This ancestor would have vanished from the western Mediterranean after the cooling associated with the onset of northern Hemisphere glaciation, about 3 Mya, as documented for other Mediterranean marine taxa. Indeed, the genus is completely stygobiont and does not occur in fluvial environments. The Pyrenees represent a watershed boundary that eliminates the possibility of the derivation of one species from the other by active dispersal after establishment in continental waters. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 387–414. 相似文献
66.
Manuel B.?MoralesEmail author Vincent?Bretagnolle Beatriz?Arroyo 《Biodiversity and Conservation》2005,14(13):3135-3150
Stochastic computer simulations are used to evaluate the sensitivity of Little bustard population parameters, estimating the
survival probabilities of the seven endangered Little bustard populations of central-western France for which conservation
actions are currentlybeing or have been implemented. Different scenarios of parameter compensation for those nuclei to establish
parameter levels assuring population viability are discussed. Adult survival, productivity per female, initial population
size and carrying capacity were the most sensitive parameters in a hypothetical, isolated population. Juvenile survival also
affected population survival, although its sensitivity was lower. Sex ratio did not have a linear effect on population survival,
but probability of extinction increased for extreme values. Productivity per female and initial population size, varied strongly
among the populations studied, determining their average time of extinction and growth rate. When a metapopulation scenario
was simulated, the survival probabilities of each population and the metapopulations stayed close to 1.0 if no mortality was
associated to migration. When mortality during migration was included in the simulations, the metapopulation's probability
of survival significantly decreased under 90%. This approach may help managers to correctly address conservation measures
and design effective strategies, which should be directed mainly to improve productivity, enhance female survival, and minimise
mortality during migration (e.g. promoting insect-rich nesting substrates, avoiding female killing and nest destruction at
harvesting, reducing the risk of collision with powerlines, or controlling poaching). 相似文献
67.
Thirty-four species of ostracodes are collected in the platform series of the Southern Corbières; two biostratigraphical assemblages, with 13 and 29 species, are respectively recognized in Cenomanian and Upper Turonian; palaeoecology is specified. At that time, the ostracode sub-province of South-West France, established on Southern Corbières, Aquitaine, Touraine-Poitou-Charentes region and Provence, is connected with Eastern and Northern regions and countries: Sub-alpines ranges, Paris Basin, Great Britain, Switzerland and Bohemia, and with the Iberian Peninsula, sub-province of North-Central Spain and Western Portuguese Basin. The crossing of the Tethys and the Atlantic Ocean is realized, in Turonian, by some rare species. 相似文献
68.
Romain Vullo Eric Buffetaut Didier Néraudeau Jean Le Lœuff Jean-François Heil Michèle Dunand 《Annales de Paléontologie》2012
The “Megalosaur” remains from Saint-Agnant (Charente-Maritime, France), reported as early as 1881 by Boissellier, are here described and figured for the first time. These bones, as well as a few additional specimens from the nearby locality of Soubise, belong in fact to an indeterminate sauropod. The stratigraphical position of these remains unambiguously indicates an infra-Cenomanian age. However, the presence in this area of continental deposits with Purbeckian and Wealden facies does not allow to decide between an earliest or late Early Cretaceous age. 相似文献
69.
70.
Cheaib A Badeau V Boe J Chuine I Delire C Dufrêne E François C Gritti ES Legay M Pagé C Thuiller W Viovy N Leadley P 《Ecology letters》2012,15(6):533-544
Model-based projections of shifts in tree species range due to climate change are becoming an important decision support tool for forest management. However, poorly evaluated sources of uncertainty require more scrutiny before relying heavily on models for decision-making. We evaluated uncertainty arising from differences in model formulations of tree response to climate change based on a rigorous intercomparison of projections of tree distributions in France. We compared eight models ranging from niche-based to process-based models. On average, models project large range contractions of temperate tree species in lowlands due to climate change. There was substantial disagreement between models for temperate broadleaf deciduous tree species, but differences in the capacity of models to account for rising CO(2) impacts explained much of the disagreement. There was good quantitative agreement among models concerning the range contractions for Scots pine. For the dominant Mediterranean tree species, Holm oak, all models foresee substantial range expansion. 相似文献