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Author Dejean, A.; Leroy, C.; Corbara, B.; Roux, O.; Cereghino, R.; Orivel, J.; Boulay, R. pdf  openurl
  Title Arboreal Ants Use the "Velcro (R) Principle'' to Capture Very Large Prey Type Journal Article
  Year (up) 2010 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 5 Issue 6 Pages e11331  
  Keywords  
  Abstract Plant-ants live in a mutualistic association with host plants known as "myrmecophytes'' that provide them with a nesting place and sometimes with extra-floral nectar (EFN) and/or food bodies (FBs); the ants can also attend sap-sucking Hemiptera for their honeydew. In return, plant-ants, like most other arboreal ants, protect their host plants from defoliators. To satisfy their nitrogen requirements, however, some have optimized their ability to capture prey in the restricted environment represented by the crowns of trees by using elaborate hunting techniques. In this study, we investigated the predatory behavior of the ant Azteca andreae which is associated with the myrmecophyte Cecropia obtusa. We noted that up to 8350 ant workers per tree hide side-by-side beneath the leaf margins of their host plant with their mandibles open, waiting for insects to alight. The latter are immediately seized by their extremities, and then spread-eagled; nestmates are recruited to help stretch, carve up and transport prey. This group ambush hunting technique is particularly effective when the underside of the leaves is downy, as is the case for C. obtusa. In this case, the hook-shaped claws of the A. andreae workers and the velvet-like structure of the underside of the leaves combine to act like natural Velcro (R) that is reinforced by the group ambush strategy of the workers, allowing them to capture prey of up to 13,350 times the mean weight of a single worker.  
  Address [Dejean, Alain; Leroy, Celine; Roux, Olivier; Orivel, Jerome] CNRS, Ecol Forets Guyane UMR CNRS 8172, Kourou, France, Email: alain.dejean@wanadoo.fr  
  Corporate Author Thesis  
  Publisher PUBLIC LIBRARY SCIENCE Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000279140800028 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 56  
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Author Stahl, C.; Burban, B.; Bompy, F.; Jolin, Z.B.; Sermage, J.; Bonal, D. openurl 
  Title Seasonal variation in atmospheric relative humidity contributes to explaining seasonal variation in trunk circumference of tropical rain-forest trees in French Guiana Type Journal Article
  Year (up) 2010 Publication Journal of Tropical Ecology Abbreviated Journal J. Trop. Ecol.  
  Volume 26 Issue Pages 393-405  
  Keywords bark; drought; secondary growth; seasonality; tropical rain forest; water  
  Abstract Large seasonal variation in the rate of change in girth of tropical rain-forest tree species has been described, but its origin is still under debate. We tested whether this variation might be related to variation in atmospheric relative humidity through its influence on bark water content and thickness. Variation in trunk circumference of 182 adult trees was measured about twice a month in an undisturbed tropical rain forest over 18 mo using dendrometers. Furthermore, a laboratory experiment was conducted to test the direct influence of relative air humidity on bark water content and thickness. in the field, most trees displayed highly positive rates of change in girth at the onset of the wet season, while a quarter of the trees displayed negative changes during long dry seasons, whatever their total annual growth. This variation was correlated with environmental conditions, particularly with atmospheric relative humidity. Trees with high bark water content and thickness displayed a stronger decrease in girth during the dry season. in the chamber experiment, desiccation induced a decrease in the diameter of the trunk sections in tandem with a decrease in bark water content. As a result, seasonal variation in the rate of change in girth of tropical rain-forest trees reflects variation in trunk biophysical properties, through the influence of relative humidity on bark properties. but not directly variation in secondary growth.  
  Address [Stahl, Clement; Burban, Benoit; Bompy, Felix; Jolin, Zachari B.; Sermage, Juliette; Bonal, Damien] INRA, UMR Ecol Forets Guyane 745, Kourou 97387, French Guiana, Email: bonal@nancy.inra.fr  
  Corporate Author Thesis  
  Publisher CAMBRIDGE UNIV PRESS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0266-4674 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000279100600005 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 57  
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Author Quesada, C.A.; Lloyd, J.; Schwarz, M.; Patino, S.; Baker, T.R.; Czimczik, C.; Fyllas, N.M.; Martinelli, L.; Nardoto, G.B.; Schmerler, J.; Santos, A.J.B.; Hodnett, M.G.; Herrera, R.; Luizao, F.J.; Arneth, A.; Lloyd, G.; Dezzeo, N.; Hilke, I.; Kuhlmann, I.; Raessler, M.; Brand, W.A.; Geilmann, H.; Moraes, J.O.; Carvalho, F.P.; Araujo, R.N.; Chaves, J.E.; Cruz, O.F.; Pimentel, T.P.; Paiva, R. openurl 
  Title Variations in chemical and physical properties of Amazon forest soils in relation to their genesis Type Journal Article
  Year (up) 2010 Publication Biogeosciences Abbreviated Journal Biogeosciences  
  Volume 7 Issue 5 Pages 1515-1541  
  Keywords  
  Abstract Soil samples were collected in six South American countries in a total of 71 different 1 ha forest plots across the Amazon Basin as part of the RAINFOR project. They were analysed for total and exchangeable cations, C, N, pH with various P fractions also determined. Physical properties were also examined and an index of soil physical quality proposed. A diverse range of soils was found. For the western areas near the Andean cordillera and the southern and northern fringes, soils tend to be distributed among the lower pedogenetic levels, while the central and eastern areas of Amazonia have more intensely weathered soils. This gives rise to a large variation of soil chemical and physical properties across the Basin, with soil properties varying predictably along a gradient of pedogenic development. Nutrient pools generally increased slightly in concentration from the youngest to the intermediate aged soils after which a gradual decline was observed with the lowest values found in the most weathered soils. Soil physical properties were strongly correlated with soil fertility, with favourable physical properties occurring in highly weathered and nutrient depleted soils and with the least weathered, more fertile soils having higher incidence of limiting physical properties. Soil phosphorus concentrations varied markedly in accordance with weathering extent and appear to exert an important influence on the nitrogen cycle of Amazon forest soils.  
  Address [Quesada, C. A.; Lloyd, J.; Baker, T. R.; Fyllas, N. M.] Univ Leeds, Sch Geog, Earth & Biosphere Inst, Leeds LS2 9JT, W Yorkshire, England, Email: betoquesada@yahoo.com.br  
  Corporate Author Thesis  
  Publisher COPERNICUS GESELLSCHAFT MBH Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1726-4170 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000278184500011 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 58  
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Author Cereghino, R.; Leroy, C.; Dejean, A.; Corbara, B. openurl 
  Title Ants mediate the structure of phytotelm communities in an ant-garden bromeliad Type Journal Article
  Year (up) 2010 Publication Ecology Abbreviated Journal Ecology  
  Volume 91 Issue 5 Pages 1549-1556  
  Keywords Aechmea mertensii; ant-gardens; biodiversity; bromeliads; Camponotus femoratus; Crematogaster levior; macroinvertebrates; mutualism; Pachycondyla goeldii; phytotelmata; secondary forest; Sinnamary; French Guiana; species interactions  
  Abstract The main theories explaining the biological diversity of rain forests often confer a limited understanding of the contribution of interspecific interactions to the observed patterns. We show how two-species mutualisms can affect much larger segments of the invertebrate community in tropical rain forests. Aechmea mertensii (Bromeliaceae) is both a phytotelm (plant-held water) and an ant-garden epiphyte. We studied the influence of its. associated ant species (Pachycondyla goeldii and Camponotus femoratus) on the physical characteristics of the plants, and, subsequently, on the diversity of the invertebrate communities that inhabit their tanks. As dispersal agents for the bromeliads, P. goeldii and C. femoratus influence the shape and size of the bromeliad by determining the location of the seedling, from exposed to partially shaded areas. By coexisting on a local scale, the two ant species generate a gradient of habitat conditions in terms of available resources (space and food) for aquatic invertebrates, the diversity of the invertebrate communities increasing with greater volumes of water and fine detritus. Two-species mutualisms are widespread in nature, but their influence on the diversity of entire communities remains largely unexplored. Because macroinvertebrates constitute an important part of animal production in all ecosystem types, further investigations should address the functional implications of such indirect effects.  
  Address [Cereghino, Regis] Univ Toulouse, UPS, INPT, Lab Ecol Fonct,EcoLab, F-31062 Toulouse, France, Email: cereghin@cict.fr  
  Corporate Author Thesis  
  Publisher ECOLOGICAL SOC AMER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0012-9658 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000277867600030 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 59  
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Author Derory, J.; Scotti-Saintagne, C.; Bertocchi, E.; Le Dantec, L.; Graignic, N.; Jauffres, A.; Casasoli, M.; Chancerel, E.; Bodenes, C.; Alberto, F.; Kremer, A. openurl 
  Title Contrasting relationships between the diversity of candidate genes and variation of bud burst in natural and segregating populations of European oaks Type Journal Article
  Year (up) 2010 Publication Heredity Abbreviated Journal Heredity  
  Volume 104 Issue 5 Pages 438-448  
  Keywords nucleotide diversity; candidate gene; QTL; Qeurcus petraea  
  Abstract Nucleotide diversity was assessed within nine candidate genes (CGs) (in total 4.6 kb) for the time of bud burst in nine sessile oak (Quercus petraea) populations distributed in central and northern Europe. The sampled populations were selected on the basis of their contrasting times of bud burst observed in common garden experiments (provenance tests). The CGs were selected according to their expression profiles during the transition from quiescent to developing buds and/or their functional role in model plants. The overall nucleotide diversity was large (pi(tot) = 6.15 x 10(-3); pi(silent) = 11.2 x 10(-3)), but population differentiation was not larger than for microsatellites. No outlier single-nucleotide polymorphism (SNP) departing from neutral expectation was found among the total of 125 SNPs. These results contrasted markedly with the significant associations that were observed between the CGs and bud burst in segregating populations. Quantitative trait loci (QTLs) for bud burst were identified for 13 year*site seasonal observations in a cloned mapping pedigree. Nineteen QTLs were detected, and QTLs located on linkage groups 2, 5 and 9 contributed repeatedly to more than 12% of the phenotypic variation of the trait. Eight genes were polymorphic in the two parents of the pedigree and could be mapped on the existing genetic map. Five of them located within the confidence intervals of QTLs for bud burst. Interestingly, four of them located within the three QTLs exhibiting the largest contributions to bud burst. Heredity (2010) 104, 438-448; doi:10.1038/hdy.2009.134; published online 7 October 2009  
  Address [Derory, J.; Scotti-Saintagne, C.; Bertocchi, E.; Graignic, N.; Jauffres, A.; Casasoli, M.; Chancerel, E.; Bodenes, C.; Alberto, F.; Kremer, A.] INRA, BIOGECO UMR1202, F-33610 Cestas, France, Email: antoine.kremer@pierroton.inra.fr  
  Corporate Author Thesis  
  Publisher NATURE PUBLISHING GROUP Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-067X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000276952000005 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 60  
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Author Jaouen, G.; Fournier, M.; Almeras, T. openurl 
  Title Thigmomorphogenesis versus light in biomechanical growth strategies of saplings of two tropical rain forest tree species Type Journal Article
  Year (up) 2010 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 67 Issue 2 Pages 211  
  Keywords biomechanics; thigmomorphogenesis; height growth strategies; tropical rain forest; French Guiana  
  Abstract In the dense tropical rainforest understorey, saplings exhibit different growth strategies aiming at reaching light levels better fitting their ecology. Investing mainly in height growth, at the expense of their width, a lot are close to mechanical instability. Tachigali melinonii, a long living heliophilic tree species, is frequently observed to be extremely slender and supported by neighbours. Such observations suggest an active growth control through the perception of mechanical environment. Mechanical environment or light availability, which one is the most influent on growth and slenderness (H/D)? To test this question, we recorded growth of control and staked saplings of two species with contrasting habits and ecology: T. melinonii, and Dicorynia guianensis, along a natural light gradient. Dicorynia, the more stable, responded more clearly to the staking treatment, showing slenderness increase when light is available, whereas for Tachigali, only light availability governed growth. For Tachigali, growth allocation is mainly governed by light availability and ontogeny, whereas Dicorynia is probably similar to the average tree strategy, using the thigmomorphogenetic physiological process to control its stability.  
  Address [Jaouen, Gaelle; Almeras, Tancrede] Univ Antilles Guyane, INRA, CNRS,Cirad, Unite Mixte Rech Ecol Forets Guyane,AgroParisTech, Kourou 97379, French Guiana, Email: gaelle.jaouen@ecofog.gf  
  Corporate Author Thesis  
  Publisher EDP SCIENCES S A Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-4560 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000276507100012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 61  
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Author Baraloto, C.; Marcon, E.; Morneau, F.; Pavoine, S.; Roggy, J.C. openurl 
  Title Integrating functional diversity into tropical forest plantation designs to study ecosystem processes Type Journal Article
  Year (up) 2010 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 67 Issue 3 Pages 303  
  Keywords complementarity; ecosystem function; functional groups; leaf economics spectrum; nitrogen fixation; quadratic entropy  
  Abstract The elucidation of relationships between biodiversity and ecosystem processes has been limited by the definition of metrics of biodiversity and their integration into experimental design. Functional trait screening can strengthen the performance of these designs. We suggest the use of Rao's quadratic entropy to measure both functional diversity and phylogenetic diversity of species mixtures proposed for an experimental design, and demonstrate how they can provide complementary information. We also present an index assessing the statistical performance of these independent variables in different experimental designs. Measurement of independent variables as continuous vs. discrete variables reduces statistical performance, but improves the model by quantifying species differences masked by group assignments. To illustrate these advances, we present an example from a tropical forest tree community in which we screened 38 species for nine functional traits. The proposed TropiDEP design is based on the relative orthogonality of two multivariate trait axes defined using principal component analysis. We propose that independent variables describing functional diversity might be grouped to calculate independent variables describing suites of different traits with potentially different effects on particular ecosystem processes. In other systems these axes may differ from those reported here, yet the methods of analysis integrating functional and phylogenetic diversity into experimental design could be universal.  
  Address [Baraloto, Christopher; Roggy, Jean-Christophe] INRA, UMR Ecol Forets Guyane, Kourou, French Guiana, Email: chris.baraloto@ecofog.gf  
  Corporate Author Thesis  
  Publisher EDP SCIENCES S A Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-4560 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000276507800004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 62  
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Author Coste, S.; Roggy, J.C.; Sonnier, G.; Dreyer, E. openurl 
  Title Similar irradiance-elicited plasticity of leaf traits in saplings of 12 tropical rainforest tree species with highly different leaf mass to area ratio Type Journal Article
  Year (up) 2010 Publication Functional Plant Biology Abbreviated Journal Funct. Plant Biol.  
  Volume 37 Issue 4 Pages 342-355  
  Keywords functional diversity; light availability; photosynthetic nitrogen use efficiency; photosynthetic capacity; tropical rainforest  
  Abstract Leaf traits of tropical tree species display an important inter-specific diversity, as detected for instance in the large range of values of leaf mass : area ratio (LMA). They also demonstrate a large irradiance-elicited plasticity, but there is still debate whether this plasticity differs among species. To address this question, leaf traits were recorded on saplings from 12 rainforest tree species in French Guiana, grown under approximately 5, 10 and 20% relative irradiance. Fifteen structural and physiological leaf traits related to photosynthesis were measured. The irradiance-elicited plasticity was quantified using a relative distance plasticity index. A large inter-specific diversity was detected for all leaf traits. A principal component analysis opposed species with a large mass-based photosynthesis, respiration, N content and photosynthetic nitrogen use efficiency, to species with a large leaf mass : area ratio, LMA. The two pioneer species used in this study displayed the largest photosynthetic capacity (and lowest LMA) and ranked at one end of the species continuum. Relative irradiance affected almost all traits with the exception of mass-based photosynthesis. A weak interaction was found between species and relative irradiance and the species ranking was maintained among relative irradiance treatments for the majority of the traits. A principal component analysis of the values of relative-distance plasticity index failed to reveal any consistent patterns of traits or species. We concluded that irradiance-elicited plasticity of leaf traits was similar among species irrespective of LMA and successional status, despite the occurrence of a large inter-specific diversity for the investigated traits.  
  Address [Dreyer, Erwin] Nancy Univ, INRA, UMR Ecol & Ecophysiol Forestieres 1137, IFR Ecosyst Forestiers Agroressources Biomol & Al, F-54280 Champenoux, France, Email: dreyer@nancy.inra.fr  
  Corporate Author Thesis  
  Publisher CSIRO PUBLISHING Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1445-4408 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000275979100009 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 63  
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Author Dejean, A.; Carpenter, J.M.; Gibernau, M.; Leponce, M.; Corbara, B. openurl 
  Title Nest relocation and high mortality rate in a Neotropical social wasp: Impact of an exceptionally rainy La Nina year Type Journal Article
  Year (up) 2010 Publication Comptes Rendus Biologies Abbreviated Journal C. R. Biol.  
  Volume 333 Issue 1 Pages 35-40  
  Keywords Vespidae; Population size variation; Microevolution; La Nina; French Guiana  
  Abstract After noting the forecast of a La Nina episode, associated with heavy rainfall in French Guiana, we monitored the fate of wasp nests before and during the 2006 short rainy season. The population of the most abundant epiponine wasp species, Polybia bistriata, decreased dramatically during the short rainy season (60.6% of the nests disappeared) then remained low for at least 18 months. Colonies that survived moved from the shelter of large, low leaves (a situation well adapted to the previous dry season) of the most frequent substrate tree, Clusia grandiflora (Clusiaceae), to upper leaves, better ventilated and whose orientation provides good protection from the rain. Therefore, the possibility of moving the nest higher during the first rains following the dry season seems very adaptive as colonies that do not do so are eliminated during the La Nina years, whose frequency will increase with global climate change. (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.  
  Address [Dejean, Alain; Gibernau, Marc] CNRS, UMR Ecofog 8172, F-97387 Kourou, France, Email: alain.dejean@wanadoo.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1631-0691 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000275984200006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 64  
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Author Leroy, C.; Jauneau, A.; Quilichini, A.; Dejean, A.; Orivel, J. openurl 
  Title Comparative Structure and Ontogeny of the Foliar Domatia in Three Neotropical Myrmecophytes Type Journal Article
  Year (up) 2010 Publication American Journal of Botany Abbreviated Journal Am. J. Bot.  
  Volume 97 Issue 4 Pages 557-565  
  Keywords anatomy; ant-plant mutualism; Chrysobalanaceae; domatia; French Guiana; Hirtella physophora; Maieta guianensis; Melastomataceae; myrmecophyte; ontogeny; Tococa guianensis  
  Abstract The origin and timing of the appearance of leaf domatia during the ontogeny of plants are important evolutionary traits driving the maintenance of ant-plant associations. In this study conducted in French Guiana on Hirtella physophora, Maieta guianensis, and Tococa guianensis, we focused on the formation and development of leaf domatia having different morphological origins. We modeled the timing of the onset of these domatia, then compared their morpho-anatomical structure. Although the ontogenetic development of the domatia differed between species, they developed very early in the plant's ontogeny so that we did not note differences in the timing of the onset of these domatia. For H. physophora seedlings, a transitional leaf forms before the appearance of fully developed domatia, whereas in M. guianensis and T. guianensis the domatia forms abruptly without transitional leaves. Moreover, in all cases, the morpho-anatomical structure of the domatia differed considerably from the lamina. All three species had similar morpho-anatomical characteristics for the domatia, indicating a convergence in their structural and functional characteristics. This convergence between taxonomically distant plant species bearing domatia having different morphological origins could be interpreted as a product of the plant's evolution toward the morphology and anatomy most likely to maximize ant recruitment and long-term residence.  
  Address [Leroy, Celine; Dejean, Alain] CNRS, Unite Mixte Rech Ecol Forets Guyane, F-97379 Kourou, France, Email: Celine.Leroy@ecofog.gf  
  Corporate Author Thesis  
  Publisher BOTANICAL SOC AMER INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-9122 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000276045500003 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 65  
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