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Author Szilagyi, A.; Scheuring, I.; Edwards, D.P.; Orivel, J.; Yu, D.W.
Title The evolution of intermediate castration virulence and ant coexistence in a spatially structured environment Type Journal Article
Year 2009 Publication Ecology Letters Abbreviated Journal (up) 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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Author Paine, C.E.T.; Norden, N.; Chave, J.; Forget, P.-M.; Fortunel, C.; Dexter, K.G.; Baraloto, C.
Title Phylogenetic density dependence and environmental filtering predict seedling mortality in a tropical forest Type Journal Article
Year 2012 Publication Ecology Letters Abbreviated Journal (up) Ecol. Lett.
Volume 15 Issue 1 Pages 34-41
Keywords Community assembly; Density dependence; French Guiana; Generalised linear mixed models; Janzen-Connell hypothesis; Seedling recruitment; Species coexistence; Survival
Abstract Negative density dependence (NDD) and environmental filtering (EF) shape community assembly, but their relative importance is poorly understood. Recent studies have shown that seedling's mortality risk is positively related to the phylogenetic relatedness of neighbours. However, natural enemies, whose depredations often cause NDD, respond to functional traits of hosts rather than phylogenetic relatedness per se. To understand the roles of NDD and EF in community assembly, we assessed the effects on seedling mortality of functional similarity, phylogenetic relatedness and stem density of neighbouring seedlings and adults in a species-rich tropical forest. Mortality risks increased for common species when their functional traits departed substantially from the neighbourhood mean, and for all species when surrounded by close relatives. This indicates that NDD affects community assembly more broadly than does EF, and leads to the tentative conclusion that natural enemies respond to phylogenetically correlated traits. Our results affirm the prominence of NDD in structuring species-rich communities. © 2011 Blackwell Publishing Ltd/CNRS.
Address Department of Biology, University of Florida, Gainesville, FL 32611, United States
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1461023x (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 13 December 2011; Source: Scopus; Coden: Eclef; doi: 10.1111/j.1461-0248.2011.01705.x; Language of Original Document: English; Correspondence Address: Paine, C.E.T.; Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland; email: timothy.paine@ieu.uzh.ch Approved no
Call Number EcoFoG @ webmaster @ Serial 373
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Author Rey, O.; Estoup, A.; Vonshak, M.; Loiseau, A.; Blanchet, S.; Calcaterra, L.; Chifflet, L.; Rossi, J.-P.; Kergoat, G.J.; Foucaud, J.; Orivel, J.; Leponce, M.; Schultz, T.; Facon, B.
Title Where do adaptive shifts occur during invasion? A multidisciplinary approach to unravelling cold adaptation in a tropical ant species invading the Mediterranean area Type Journal Article
Year 2012 Publication Ecology Letters Abbreviated Journal (up) Ecol. Lett.
Volume 15 Issue 11 Pages 1266-1275
Keywords Adaptation; Biological invasion; Climatic niche shift; Cold temperature; Mediterranean zone; Wasmannia auropunctata
Abstract Evolution may improve the invasiveness of populations, but it often remains unclear whether key adaptation events occur after introduction into the recipient habitat (i.e. post-introduction adaptation scenario), or before introduction within the native range (i.e. prior-adaptation scenario) or at a primary site of invasion (i.e. bridgehead scenario). We used a multidisciplinary approach to determine which of these three scenarios underlies the invasion of the tropical ant Wasmannia auropunctata in a Mediterranean region (i.e. Israel). Species distribution models (SDM), phylogeographical analyses at a broad geographical scale and laboratory experiments on appropriate native and invasive populations indicated that Israeli populations followed an invasion scenario in which adaptation to cold occurred at the southern limit of the native range before dispersal to Israel. We discuss the usefulness of combining SDM, genetic and experimental approaches for unambiguous determination of eco-evolutionary invasion scenarios. © 2012 Blackwell Publishing Ltd/CNRS.
Address Smithsonian Institute, Department of Entomology, Natural Museum of Natural History, Washington, DC, 20013, United States
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1461023x (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 19 October 2012; Source: Scopus; Coden: Eclef; doi: 10.1111/j.1461-0248.2012.01849.x; Language of Original Document: English; Correspondence Address: Rey, O.; INRA, UMR1062, CBGP, Montpellier, France; email: olivier.rey.1@gmail.com Approved no
Call Number EcoFoG @ webmaster @ Serial 441
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Author Picard, N.; Mortier, F.; Rossi, V.; Gourlet-Fleury, S.
Title Clustering species using a model of population dynamics and aggregation theory Type Journal Article
Year 2010 Publication Ecological Modelling Abbreviated Journal (up) Ecol. Model.
Volume 221 Issue 2 Pages 152-160
Keywords Aggregation theory; Species grouping; Species richness; Tropical rainforest; Usher model
Abstract The high species diversity of some ecosystems like tropical rainforests goes in pair with the scarcity of data for most species. This hinders the development of models that require enough data for fitting. The solution commonly adopted by modellers consists in grouping species to form more sizeable data sets. Classical methods for grouping species such as hierarchical cluster analysis do not take account of the variability of the species characteristics used for clustering. In this study a clustering method based on aggregation theory is presented. It takes account of the variability of species characteristics by searching for the grouping that minimizes the quadratic error (square bias plus variance) of some model's prediction. This method allows one to check whether the gain in variance brought by data pooling compensate for the bias that it introduces. This method was applied to a data set on 94 tree species in a tropical rainforest in French Guiana, using a Usher matrix model to predict species dynamics. An optimal trade-off between bias and variance was found when grouping species. Grouping species appeared to decrease the quadratic error, except when the number of groups was very small. This clustering method yielded species groups similar to those of the hierarchical cluster analysis using Ward's method when variance was small, that is when the number of groups was small. (C) 2009 Elsevier B.V. All rights reserved.
Address [Picard, Nicolas; Mortier, Frederic; Rossi, Vivien; Gourlet-Fleury, Sylvie] CIRAD, F-34398 Montpellier 5, France, Email: nicolas.picard@cirad.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 0304-3800 ISBN Medium
Area Expedition Conference
Notes ISI:000273628800004 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 85
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Author Flores, O.; Rossi, V.; Mortier, F.
Title Autocorrelation offsets zero-inflation in models of tropical saplings density Type Journal Article
Year 2009 Publication Ecological Modelling Abbreviated Journal (up) Ecol. Model.
Volume 220 Issue 15 Pages 1797-1809
Keywords Hierarchical Bayesian Modelling; Conditional Auto-Regressive model; Variable selection; Zero-Inflated Poisson; Posterior predictive; Paracou; French Guiana
Abstract Modelling the local density of tropical saplings can provide insights into the ecological processes that drive species regeneration and thereby help predict population recovery after disturbance. Yet, few studies have addressed the challenging issues in autocorrelation and zero-inflation of local density. This paper presents Hierarchical Bayesian Modelling (HBM) of sapling density that includes these two features. Special attention is devoted to variable selection, model estimation and comparison. We developed a Zero-Inflated Poisson (ZIP) model with a latent correlated spatial structure and compared it with non-spatial ZIP and Poisson models that were either autocorrelated (Spatial Generalized Linear Mixed, SGLM) or not (generalized linear models, GLM). In our spatial models, local density autocorrelation was modeled by a Conditional Auto-Regressive (CAR) process. 13 explicative variables described ecological conditions with respect to topography, disturbance, stand structure and intraspecific processes. Models were applied to six tropical tree species with differing biological attributes: Oxandra asbeckii, Eperua falcata, Eperua grandiflora, Dicorynia guianensis, Qualea rosea, and Tachigali melinonii. We built species-specific models using a simple method of variable selection based on a latent binary indicator. Our spatial models showed a close correlation between observed and estimated densities with site spatial structure being correctly reproduced. By contrast, the non-spatial models showed poor fits. Variable selection highlighted species-specific requirements and susceptibility to local conditions. Model comparison overall showed that the SGLM was the most accurate explanatory and predictive model. Surprisingly, zero-inflated models performed less well. Although the SZIP model was relevant with respect to data distribution, and more flexible with respect to response curves, its model complexity caused marked variability in parameter estimates. In the SUM, the spatial process alone accounted for zero-inflation in the data. A refinement of the hypotheses employed at the process level could compensate for distribution flaws at the data level. This study emphasized the importance of the HBM framework in improving the modelling of density-environment relationships. (C) 2008 Elsevier B.V. All rights reserved.
Address [Flores, O.] CNRS, Ctr Ecol Fonct & Evolut, UMR 5175, F-34293 Montpellier 5, France, Email: olivierflores@free.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 0304-3800 ISBN Medium
Area Expedition Conference
Notes ISI:000267585400007 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 201
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Author Phillips, P.D.; Thompson, I.S.; Silva, J.N.M.; van Gardingen, P.R.; Degen, B.
Title Scaling up models of tree competition for tropical forest population genetics simulation Type Journal Article
Year 2004 Publication Ecological Modelling Abbreviated Journal (up) Ecol. Model.
Volume 180 Issue 2-3 Pages 419-434
Keywords tropical rain; forest; population genetics; model SYMFOR; eco-gene; scaling up; competition
Abstract Understanding the effects of logging activity on genetic diversity is an important aspect of establishing the sustainability of selective logging management operations in tropical forests. Genetic variation is affected by selective logging directly, through the removal of and damage to trees within the population, and indirectly, through a change in the forest structure and environment in which the remaining population lives. Eco-Gene is a population genetics model applied to tropical forests over a scale of hundreds of hectares. SYMFOR is a modelling framework for individual-based spatially explicit ecological and management models applied to tropical forests over a scale of 0.25 4 ha. We have linked the models to enable simulations using processes involved in both models. To overcome problems of scale, the spatially explicit competition index calculated in SYMFOR simulations has been modelled such that it can be applied at scales representing much larger areas for which the data are not available, as required by Eco-Gene. The competition index is modelled as a distribution on a grid-square basis, and implemented in the linked Eco-Gene/SYMFOR system. Each tree within a grid-square is given a “relative competition” within the distribution, biased according to species. A competition index value is obtained for the tree by transforming the grid-square distribution to be relevant to the size of the tree, and extracting a value according to the tree's relative competition within the distribution. The distribution and each tree's relative competition within it change according to the effects of growth, mortality and logging activity. The model was calibrated using data from the Tapajos region of the Eastern Amazon forest. This paper describes the model, its calibration and validation and the implications of scaling up from an explicit representation to a modelled quantity. (C) 2004 Elsevier B.V. All rights reserved.
Address Embrapa Amazonia Oriental, BR-66095100 Belem, Para, Brazil, Email: paul.phillips@envams.co.uk
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 0304-3800 ISBN Medium
Area Expedition Conference
Notes ISI:000224635700012 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 234
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Author Phillips, P.D.; de Azevedo, C.P.; Degen, B.; Thompson, I.S.; Silva, J.N.M.; van Gardingen, P.R.
Title An individual-based spatially explicit simulation model for strategic forest management planning in the eastern Amazon Type Journal Article
Year 2004 Publication Ecological Modelling Abbreviated Journal (up) Ecol. Model.
Volume 173 Issue 4 Pages 335-354
Keywords model; individual; tropical forest; tree; spatial; Brazil; Amazon; competition; species grouping; management; certification; regulation
Abstract A model to simulate the ecological processes of tree growth, mortality and recruitment, and the processes of forest management, in the terra firme forests of the eastern Amazon is described. It is implemented within the SYMFOR (http://www.symfor.org) framework. It is based on measurements of all trees that have a diameter greater than 5 cm from experimental plots in the Jari Cellulose and Tapajos National Forest areas over a 16-year period. Ten species groups are used to describe the natural processes affecting tree behaviour. Growth rates are calculated for each species group using the tree diameter and a competition index. Mortality and recruitment are simulated as stochastic processes. Recruitment probability is based on the predicted growth rate of a hypothetical tree. Options exist to vary the human interaction with the forest reflecting forest management decisions, as for other SYMFOR models. Model evaluation compares the performance of the model with data describing forest recovery for 16 years following logging. The model was applied to simulate current forest management practice in the Brazilian Amazon, with 40 m(3) ha(-1) of timber extracted with a cutting cycle of 30 years. Results show that yields are sustained for three harvests following the first logging of primary forest, but that the composition of timber moves towards lightwooded species rather than hardwooded. The predicted size of extracted trees decreases and the number of trees extracted increases with successive harvests, leading to a prediction of increased costs and lower profits for the logging company despite constant yields. The standing volume of all trees just before harvest is reduced by 15% over 150 years, with pioneer species becoming increasingly prevalent in the stand. The model, in the SYMFOR framework, can be used to help understand the differences between alternative forest management strategies in the Brazilian Amazon. Such knowledge is required to improve forest management, regulation and certification, and help to conserve the worlds largest remaining tropical forest. (C) 2003 Elsevier B.V. All rights reserved.
Address EMBRAPA Amazonia Oriental, BR-69011970 Manaus, Amazonas, Brazil, Email: Paul.Phillips@envams.co.uk
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 0304-3800 ISBN Medium
Area Expedition Conference
Notes ISI:000220392200002 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 238
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Author Talaga, S.; Delabie, J.H.C.; Dezerald, O.; Salas-Lopez, A.; Petitclerc, F.; Leroy, C.; Herault, B.; Céréghino, R.; Dejean, A.
Title A bromeliad species reveals invasive ant presence in urban areas of French Guiana Type Journal Article
Year 2015 Publication Ecological Indicators Abbreviated Journal (up) Ecological Indicators
Volume 58 Issue Pages 1-7
Keywords Aechmea aquilega; Bioindicators; Non-specific ant-plant relationships; Surrogacy; Tank bromeliads; Urban ecology
Abstract Tank bromeliads, frequently associated with ants, are considered 'biodiversity amplifiers' for both aquatic and terrestrial organisms, and thus have a high ecological value. The focal species of this study, Aechmea aquilega, sheltered the colonies of 12 ant species in a Guianese rural habitat where Odontomachus haematodus, associated with 60% of these plants, was the most frequent. Unexpectedly, the ant species richness was higher in a compared urban habitat with 21 species, but two synanthropic and four invasive ants were noted among them. Consequently, we conducted baiting surveys (on the ground, on trees and on trees bearing A. aquilega) as well as complementary surveys using different sampling modes in urban areas to test if A. aquilega is a surrogate revealing the presence of certain invasive ants. During the baiting survey, we recorded four Neotropical and eight introduced invasive ants out of a total of 69 species. Of these 12 invasive species, five were noted by baiting A. aquilega (including two only noted in this way). A bootstrap simulation permitted us to conclude that A. aquilega significantly concentrates certain species of invasive ants. This was confirmed by complementary surveys, where we did not record further species. We conclude that baiting on trees bearing large epiphytes in human-modified, Neotropical areas is a relevant complement to the early detection of invasive ants. © 2015 Elsevier Ltd. All rights reserved.
Address CNRS Ecolab (UMR-CNRS 5245), 118 Route de Narbonne, Toulouse, France
Corporate Author Thesis
Publisher Place of Publication Editor
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Notes Export Date: 23 June 2015 Approved no
Call Number EcoFoG @ webmaster @ Serial 607
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Author Jona Lasinio, G.; Pollice, A.; Marcon, E.; Fano, E.A.
Title Assessing the role of the spatial scale in the analysis of lagoon biodiversity. A case-study on the macrobenthic fauna of the Po River Delta Type Journal Article
Year 2017 Publication Ecological Indicators Abbreviated Journal (up) Ecological Indicators
Volume 80 Issue Pages 303-315
Keywords Biodiversity partitioning; Lagoon biodiversity; Macrobenthic fauna; Mixed effects models; Tsallis entropy
Abstract The analysis of benthic assemblages is a valuable tool to describe the ecological status of transitional water ecosystems, but species are extremely sensitive and respond to both microhabitat and seasonal differences. The identification of changes in the composition of the macrobenthic community in specific microhabitats can then be used as an “early warning” for environmental changes which may affect the economic and ecological importance of lagoons, through their provision of Ecosystem Services. From a conservational point of view, the appropriate definition of the spatial aggregation level of microhabitats or local communities is of crucial importance. The main objective of this work is to assess the role of the spatial scale in the analysis of lagoon biodiversity. First, we analyze the variation in the sample coverage for alternative aggregations of the monitoring stations in three lagoons of the Po River Delta. Then, we analyze the variation of a class of entropy indices by mixed effects models, properly accounting for the fixed effects of biotic and abiotic factors and random effects ruled by nested sources of variability corresponding to alternative definitions of local communities. Finally, we address biodiversity partitioning by a generalized diversity measure, namely the Tsallis entropy, and for alternative definitions of the local communities. The main results obtained by the proposed statistical protocol are presented, discussed and framed in the ecological context. © 2017 Elsevier Ltd
Address Dipartimento di Scienze della Vita e Biotecnologie, Università degli Studi di Ferrara, Ferrara, Italy
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Notes Export Date: 12 June 2017 Approved no
Call Number EcoFoG @ webmaster @ Serial 755
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Author Cereghino, R.; Leroy, C.; Dejean, A.; Corbara, B.
Title Ants mediate the structure of phytotelm communities in an ant-garden bromeliad Type Journal Article
Year 2010 Publication Ecology Abbreviated Journal (up) 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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