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Author Almeras, T.; Fournier, M. openurl 
  Title Biomechanical design and long-term stability of trees: Morphological and wood traits involved in the balance between weight increase and the gravitropic reaction Type Journal Article
  Year (up) 2009 Publication Journal of Theoretical Biology Abbreviated Journal J. Theor. Biol.  
  Volume 256 Issue 3 Pages 370-381  
  Keywords Mechanical design; Gravitropism; Bending stresses; Allometry; Reaction wood  
  Abstract Studies on tree biomechanical design usually focus on stem stiffness, resistance to breakage or uprooting, and elastic stability. Here we consider another biomechanical constraint related to the interaction between growth and gravity. Because stems are slender structures and are never perfectly symmetric, the increase in tree mass always causes bending movements. Given the current mechanical design of trees, integration of these movements over time would ultimately lead to a weeping habit unless some gravitropic correction occurs. This correction is achieved by asymmetric internal forces induced during the maturation of new wood. The long-term stability of a growing stem therefore depends on how the gravitropic correction that is generated by diameter growth balances the disturbance due to increasing self weight. General mechanical formulations based on beam theory are proposed to model these phenomena. The rates of disturbance and correction associated with a growth increment are deduced and expressed as a function of elementary traits of stem morphology, cross-section anatomy and wood properties. Evaluation of these traits using previously published data shows that the balance between the correction and the disturbance strongly depends on the efficiency of the gravitropic correction, which depends on the asymmetry of wood maturation strain, eccentric growth, and gradients in wood stiffness. By combining disturbance and correction rates, the gravitropic performance indicates the dynamics of stem bending during growth. It depends on stem biomechanical traits and dimensions. By analyzing dimensional effects, we show that the necessity for gravitropic correction might constrain stem allometric growth in the long-term. This constraint is compared to the requirement for elastic stability, showing that gravitropic performance limits the increase in height of tilted stem and branches. The performance of this function may thus limit the slenderness and lean of stems, and therefore the ability of the tree to capture light in a heterogeneous environment. (c) 2008 Elsevier Ltd. All rights reserved.  
  Address [Almeras, T.; Fournier, M.] INRA, UMR Ecol Forets Guyane, F-97310 Kourou, France, Email: t_almeras@hotmail.com  
  Corporate Author Thesis  
  Publisher ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-5193 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000263077100008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 123  
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Author Jabiol, J.; Corbara, B.; Dejean, A.; Cereghino, R. openurl 
  Title Structure of aquatic insect communities in tank-bromeliads in a East-Amazonian rainforest in French Guiana Type Journal Article
  Year (up) 2009 Publication Forest Ecology and Management Abbreviated Journal For. Ecol. Manage.  
  Volume 257 Issue 1 Pages 351-360  
  Keywords Bromeliaceae; Classification; Community structure; Insects; Microcosms; Neural networks; Nouragues; Phytotelmata; Species richness  
  Abstract Tank-bromeliads are discrete habitats which contain distinct aquatic communities, and which commonly occur in the neotropics. Because they span a broad range of ecological gradients in terms of habitat structure and amount of resources, researchers study the associations between the biodiversity of communities and these gradients in rainforests, where the very high species richness and densities within other continuous habitats makes it difficult to quantify animal communities. We analysed the diversity of aquatic insect communities in relation to different tank-bromeliad species in a primary rainforest (French Guiana) using artificial intelligence and complex optimization techniques to classify communities and model their determinants. First, the self-organizing map (neural network) was used to classify 158 bromeliads according to the quantitative structure of the insect communities. Catopsis berteroniana and Guzmania lingulata formed separate clusters of plants on the virtual map, while Vriesea splendens, Vriesea pleiosticha and Aechmea melinonii were grouped together in the remaining clusters. Some insect taxa occurred in all bromeliads, while other taxa were specific to a given species. Second, general linear modelling allowed us to specify the influence of the bromeliad species; water volume and volume of fine particulate organic matter inside of the tank; elevation above the ground; and sampling site on taxonomic richness and insect abundance. The number of taxa and individuals per plant increased with greater water volume, but the slope of the relationships depended on the bromeliad species. The significant influence of bromeliad species suggested that at similar water volumes different plant species had different taxon richness and insect abundance. Greater amounts of fine particulate organic matter were detrimental to community diversity in the tanks, probably because they decreased available space by clogging it and/or affected oxygen concentrations. The influence of tank-bromeliad species on the aquatic insect community was primarily related to their physical (and probably chemical) features rather than to species-specific associations sensu stricto. The classification of bromeliads with respect to animal species is likely to provide referential schemes for those biodiversity patterns to be expected under certain conditions, and may help to target model communities for subsequent experimental research. (C) 2008 Elsevier B,V. All rights reserved.  
  Address [Jabiol, J.; Cereghino, R.] Univ Toulouse 3, Ecolab, Lab Ecol Fonctionnelle, CNRS,UMR 5245, F-31062 Toulouse 9, France, Email: cereghin@cict.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER SCIENCE BV Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-1127 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000261856000038 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 124  
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Author Dejean, A.; Grangier, J.; Leroy, C.; Orivel, J. openurl 
  Title Predation and aggressiveness in host plant protection: a generalization using ants from the genus Azteca Type Journal Article
  Year (up) 2009 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften  
  Volume 96 Issue 1 Pages 57-63  
  Keywords Aggressiveness; Ant-plant relationships; Biotic defence; Predation  
  Abstract In studying the ant genus Azteca, a Neotropical group of arboreal species, we aimed to determine the extent to which the ants use predation and/or aggressiveness to protect their host plants from defoliating insects. We compared a territorially dominant, carton-nester, Azteca chartifex, and three plant-ant species. Azteca alfari and Azteca ovaticeps are associated with the myrmecophyte Cecropia (Cecropiaceae) and their colonies shelter in its hollow branches; whereas Azteca bequaerti is associated with Tococa guianensis (Melastomataceae) and its colonies shelter in leaf pouches situated at the base of the laminas. Whereas A. bequaerti workers react to the vibrations transmitted by the lamina when an alien insect lands on a leaf making it unnecessary for them to patrol their plant, the workers of the three other species rather discover prey by contact. The workers of all four species use a predatory behaviour involving spread-eagling alien insects after recruiting nestmates at short range, and, in some cases, at long range. Because A. alfari and A. ovaticeps discard part of the insects they kill, we deduced that the workers' predatory behaviour and territorial aggressiveness combine in the biotic defence of their host tree.  
  Address [Dejean, Alain; Leroy, Celine] CNRS, UMR Ecol Forets Guyane 8172, F-97379 Kourou, France, Email: alain.dejean@wanadoo.fr  
  Corporate Author Thesis  
  Publisher SPRINGER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-1042 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000261791000006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 125  
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Author Vedel, V.; Arthur, W. url  doi
openurl 
  Title Character changes during the early post-embryonic development of the centipede Strigamia maritima (Leach, 1817) (Chilopoda: Geophilomorpha) Type Journal Article
  Year (up) 2009 Publication International Journal of Myriapodology Abbreviated Journal  
  Volume 2 Issue 1 Pages 53-61  
  Keywords MOULT DEVELOPMENT ARTHROPOD POST-EMBRYONIC STAGE MORPHOLOGICAL CHANGE MYRIAPOD CENTIPEDE EVO-DEVO  
  Abstract For many kinds of ecological, evolutionary and developmental study, it is important to be able to describe the life-history of the individuals of a particular species/population. In the case of myriapods and other arthropods, this involves separating the different life-history stages (or stadia or instars) that are separated by moults. However, it has recently been pointed out that in the earliest post-embryonic stages the cuticle is still quite flexible; this means that visible external developmental changes can occur between moults as well as during them. Here, we provide evidence for such inter-moult changes in the coastal geophilomorph centipede Strigamia maritima. The character states studied enable finer-scale resolution of early post-embryonic forms than was hitherto possible. Specifically, we describe five transitional forms during a period in which just two (Peripatoid and Foetus) have traditionally been recognized  
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  Notes Character changes during the early post-embryonic development of the centipede Strigamia maritima (Leach, 1817) (Chilopoda: Geophilomorpha); doi:10.1163/187525409X462412 Approved no  
  Call Number EcoFoG @ eric.marcon @ 13 Serial 187  
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Author Pickett, K.M.; Carpenter, J.M.; Dejean, A. openurl 
  Title “Basal” but not primitive: the nest of Apoica arborea de Saussure, 1854 (Insecta, Hymenoptera, Vespidae, Polistinae) Type Journal Article
  Year (up) 2009 Publication Zoosystema Abbreviated Journal Zoosystema  
  Volume 31 Issue 4 Pages 945-948  
  Keywords Insecta; Hymenoptera; Vespidae; Polistinae; Apoica; social wasps; nest architecture; mosaic evolution  
  Abstract The first nest of Apoica arborea ever collected is reported. Characteristics of the unusual nest design are discussed relative to other members of the genus Apoica and other epiponine genera. The characteristics of its nest architecture are a mosaic of primitive and derived features for the Polistinae, and thus the nest design is not properly interpreted as the primitive condition from which other swarm-founding wasp nest designs are derived. The frequent conflation of “basal” and primitive is discussed.  
  Address [Pickett, Kurt M.] Univ Vermont, Dept Biol, Burlington, VT 05401 USA, Email: kurt.pickett@uvm.edu  
  Corporate Author Thesis  
  Publisher PUBLICATIONS SCIENTIFIQUES DU MUSEUM, PARIS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1280-9551 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000273733000008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 188  
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Author Fouquet, A.; Dubut, V.; Hataway, R.; Scotti-Saintagne, C.; Scotti, I.; Noonan, B. doi  openurl
  Title Isolation and characterisation of 19 microsatellite loci from the Amazonian frog Adenomera andreae (Amphibia: Anura: Leptodactylidae) Type Journal Article
  Year (up) 2009 Publication Conservation Genetics Resources Abbreviated Journal Conserv. Genet. Res.  
  Volume 1 Issue 1 Pages 217-220  
  Keywords Biomedicine  
  Abstract Nineteen novel microsatellite loci were isolated from Adenomera andreae, a widespread Amazonian frog considered to be a species complex. Three multiplex kits were optimized. Genetic diversity was assessed in 66 individuals sampled in three populations along the West of the Approuague River catchment (French Guiana). We also tested the multiplex kits in four other Adenomera and nine Leptodactylus species with 43.4 and 17.5% success respectively.  
  Address  
  Corporate Author Thesis  
  Publisher Springer Netherlands Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1877-7252 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 185  
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Author Leroy, C.; Corbara, B.; Dejean, A.; Céréghino, R. openurl 
  Title Potential sources of nitrogen in an ant-garden tank-bromeliad Type Journal Article
  Year (up) 2009 Publication Plant Signaling and Behavior Abbreviated Journal Plant. Signal. Behav.  
  Volume 4 Issue 9 Pages 868-870  
  Keywords Aechmea mertensii Camponotus femoratus nitrogen nitrogen stable isotope Pachycondyla goeldii plant-insect interactions phytotelmata  
  Abstract Epiphytic plants in general and bromeliads in particular live in a water and nutrient-stressed environment often limited in nitrogen. Thus, these plants have developed different ways to survive in such an environment. We focused on Aechmea mertensii (Bromeliaceae), which is both a tank-bromeliad and an ant-garden (AG) epiphyte initiated by either the ants Camponotus femoratus or Pachycondyla goeldii. By combining a study of plant morphology and physiology associated with aquatic insect biology, we demonstrate that the ant species influences the leaf structure of the bromeliad, the structure of the aquatic community in its tank, and nutrient assimilation by the leaves. Based on nitrogen and nitrogen stable isotope measurements of the A. mertensii leaves, the leaf litter inside of the tank and the root-embedded carton nest, we discuss the potential sources of available nitrogen for the plant based on the ant partner. We demonstrate the existence of a complex ant-plant interaction that subsequently affects the biodiversity of a broader range of organisms that are themselves likely to influence nutrient assimilation by the A. mertensii leaves in a kind of plant-invertebrate-plant feedback loop.  
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  Notes Potential sources of nitrogen in an ant-garden tank-bromeliad Approved no  
  Call Number EcoFoG @ eric.marcon @ 12 Serial 186  
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Author Gonzalez, M.A.; Baraloto, C.; Engel, J.; Mori, S.A.; Petronelli, P.; Riera, B.; Roger, A.; Thebaud, C.; Chave, J. pdf  openurl
  Title Identification of Amazonian Trees with DNA Barcodes Type Journal Article
  Year (up) 2009 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 4 Issue 10 Pages e7483  
  Keywords  
  Abstract Background: Large-scale plant diversity inventories are critical to develop informed conservation strategies. However, the workload required for classic taxonomic surveys remains high and is particularly problematic for megadiverse tropical forests. Methodology/Principal Findings: Based on a comprehensive census of all trees in two hectares of a tropical forest in French Guiana, we examined whether plant DNA barcoding could contribute to increasing the quality and the pace of tropical plant biodiversity surveys. Of the eight plant DNA markers we tested (rbcLa, rpoC1, rpoB, matK, ycf5, trnL, psbA-trnH, ITS), matK and ITS had a low rate of sequencing success. More critically, none of the plastid markers achieved a rate of correct plant identification greater than 70%, either alone or combined. The performance of all barcoding markers was noticeably low in few species-rich clades, such as the Laureae, and the Sapotaceae. A field test of the approach enabled us to detect 130 molecular operational taxonomic units in a sample of 252 juvenile trees. Including molecular markers increased the identification rate of juveniles from 72% (morphology alone) to 96% (morphology and molecular) of the individuals assigned to a known tree taxon. Conclusion/Significance: We conclude that while DNA barcoding is an invaluable tool for detecting errors in identifications and for identifying plants at juvenile stages, its limited ability to identify collections will constrain the practical implementation of DNA-based tropical plant biodiversity programs.  
  Address  
  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:000270880700009 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 189  
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Author Foucaud, J.; Orivel, J.; Fournier, D.; Delabie, J.H.C.; Loiseau, A.; Le Breton, J.; Cerdan, P.; Estoup, A. openurl 
  Title Reproductive system, social organization, human disturbance and ecological dominance in native populations of the little fire ant, Wasmannia auropunctata Type Journal Article
  Year (up) 2009 Publication Molecular Ecology Abbreviated Journal Mol. Ecol.  
  Volume 18 Issue 24 Pages 5059-5073  
  Keywords biological invasion; clonality; human disturbance; parthenogenesis; social organization; Wasmannia auropunctata  
  Abstract The invasive ant species Wasmannia auropunctata displays both ecologically dominant and non-dominant populations within its native range. Three factors could theoretically explain the ecological dominance of some native populations of W. auropunctata: (i) its clonal reproductive system, through demographic and/or adaptive advantages; (ii) its unicolonial social organization, through lower intraspecific and efficient interspecific competition; (iii) the human disturbance of its native range, through the modification of biotic and abiotic environmental conditions. We used microsatellite markers and behavioural tests to uncover the reproductive modes and social organization of dominant and non-dominant native populations in natural and human-modified habitats. Microsatellite and mtDNA data indicated that dominant and non-dominant native populations (supercolonies as determined by aggression tests) of W. auropunctata did not belong to different evolutionary units. We found that the reproductive system and the social organization are neither necessary nor sufficient to explain W. auropunctata ecological dominance. Dominance rather seems to be set off by unknown ecological factors altered by human activities, as all dominant populations were recorded in human-modified habitats. The clonal reproductive system found in some populations of W. auropunctata may however indirectly contribute to its ecological dominance by allowing the species to expand its environmental niche, through the fixation over time of specific combinations of divergent male and female genotypes. Unicoloniality may rather promote the range expansion of already dominant populations than actually trigger ecological dominance. The W. auropunctata model illustrates the strong impact of human disturbance on species' ecological features and the adaptive potential of clonal reproductive systems.  
  Address [Foucaud, Julien; Fournier, Denis; Loiseau, Anne; Estoup, Arnaud] Montpellier SupAgro, Cirad, IRD, INRA,UMR CBGP, F-34988 Montferrier Sur Lez, France, Email: julien.foucaud@legs.cnrs-gif.fr  
  Corporate Author Thesis  
  Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-1083 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000272452700009 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 191  
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Author Szilagyi, A.; Scheuring, I.; Edwards, D.P.; Orivel, J.; Yu, D.W. openurl 
  Title The evolution of intermediate castration virulence and ant coexistence in a spatially structured environment Type Journal Article
  Year (up) 2009 Publication Ecology Letters Abbreviated Journal Ecol. Lett.  
  Volume 12 Issue 12 Pages 1306-1316  
  Keywords Cooperation; evolution of virulence; host-pathogen; mutualism; myrmecophyte; parasite; rock-paper-scissors; spatial games; tolerance; trade-off  
  Abstract Theory suggests that spatial structuring should select for intermediate levels of virulence in parasites, but empirical tests are rare and have never been conducted with castration (sterilizing) parasites. To test this theory in a natural landscape, we construct a spatially explicit model of the symbiosis between the ant-plant Cordia nodosa and its two, protecting ant symbionts, Allomerus and Azteca. Allomerus is also a castration parasite, preventing fruiting to increase colony fecundity. Limiting the dispersal of Allomerus and host plant selects for intermediate castration virulence. Increasing the frequency of the mutualist, Azteca, selects for higher castration virulence in Allomerus, because seeds from Azteca-inhabited plants are a public good that Allomerus exploits. These results are consistent with field observations and, to our knowledge, provide the first empirical evidence supporting the hypothesis that spatial structure can reduce castration virulence and the first such evidence in a natural landscape for either mortality or castration virulence.  
  Address [Edwards, David P.; Yu, Douglas W.] Univ E Anglia, Sch Biol Sci, Norwich NR4 7TJ, Norfolk, England, Email: dougwyu@gmail.com  
  Corporate Author Thesis  
  Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1461-023X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000271631500006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 192  
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