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Author Chave, J.; Navarrete, D.; Almeida, S.; Alvarez, E.; Aragao, L.E.O.C.; Bonal, D.; Chatelet, P.; Silva-Espejo, J.E.; Goret, J.Y.; von Hildebrand, P.; Jimenez, E.; Patino, S.; Penuela, M.C.; Phillips, O.L.; Stevenson, P.; Malhi, Y. openurl 
  Title Regional and seasonal patterns of litterfall in tropical South America Type Journal Article
  Year (down) 2010 Publication Biogeosciences Abbreviated Journal Biogeosciences  
  Volume 7 Issue 1 Pages 43-55  
  Keywords  
  Abstract The production of aboveground soft tissue represents an important share of total net primary production in tropical rain forests. Here we draw from a large number of published and unpublished datasets (n=81 sites) to assess the determinants of litterfall variation across South American tropical forests. We show that across old-growth tropical rainforests, litterfall averages 8.61 +/- 1.91 Mg ha(-1) yr(-1) (mean +/- standard deviation, in dry mass units). Secondary forests have a lower annual litterfall than old-growth tropical forests with a mean of 8.01 +/- 3.41 Mg ha(-1) yr(-1). Annual litterfall shows no significant variation with total annual rainfall, either globally or within forest types. It does not vary consistently with soil type, except in the poorest soils (white sand soils), where litterfall is significantly lower than in other soil types (5.42 +/- 1.91 Mg ha(-1) yr(-1)). We also study the determinants of litterfall seasonality, and find that it does not depend on annual rainfall or on soil type. However, litterfall seasonality is significantly positively correlated with rainfall seasonality. Finally, we assess how much carbon is stored in reproductive organs relative to photosynthetic organs. Mean leaf fall is 5.74 +/- 1.83 Mg ha(-1) yr(-1) (71% of total litterfall). Mean allocation into reproductive organs is 0.69 +/- 0.40 Mg ha(-1) yr(-1) (9% of total litterfall). The investment into reproductive organs divided by leaf litterfall increases with soil fertility, suggesting that on poor soils, the allocation to photosynthetic organs is prioritized over that to reproduction. Finally, we discuss the ecological and biogeochemical implications of these results.  
  Address [Chave, J.] CNRS UPS, Lab Evolut & Divers Biol, UMR 5174, Toulouse, France, Email: chave@cict.fr  
  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:000274058100004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 70  
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Author Coutand, C.; Chevolot, M.; Lacointe, A.; Rowe, N.; Scotti, I. openurl 
  Title Mechanosensing of stem bending and its interspecific variability in five neotropical rainforest species Type Journal Article
  Year (down) 2010 Publication Annals of Botany Abbreviated Journal Ann. Bot.  
  Volume 105 Issue 2 Pages 341-347  
  Keywords Mechanosensing; interspecific variability; trees; lianas; rain forest; neotropical species; bending; biomechanics; Bauhinia; Eperua; Symphonia; Tachigali  
  Abstract In rain forests, sapling survival is highly dependent on the regulation of trunk slenderness (height/diameter ratio): shade-intolerant species have to grow in height as fast as possible to reach the canopy but also have to withstand mechanical loadings (wind and their own weight) to avoid buckling. Recent studies suggest that mechanosensing is essential to control tree dimensions and stability-related morphogenesis. Differences in species slenderness have been observed among rainforest trees; the present study thus investigates whether species with different slenderness and growth habits exhibit differences in mechanosensitivity. Recent studies have led to a model of mechanosensing (sum-of-strains model) that predicts a quantitative relationship between the applied sum of longitudinal strains and the plant's responses in the case of a single bending. Saplings of five different neotropical species (Eperua falcata, E. grandiflora, Tachigali melinonii, Symphonia globulifera and Bauhinia guianensis) were subjected to a regimen of controlled mechanical loading phases (bending) alternating with still phases over a period of 2 months. Mechanical loading was controlled in terms of strains and the five species were subjected to the same range of sum of strains. The application of the sum-of-strain model led to a dose-response curve for each species. Dose-response curves were then compared between tested species. The model of mechanosensing (sum-of-strain model) applied in the case of multiple bending as long as the bending frequency was low. A comparison of dose-response curves for each species demonstrated differences in the stimulus threshold, suggesting two groups of responses among the species. Interestingly, the liana species B. guianensis exhibited a higher threshold than other Leguminosae species tested. This study provides a conceptual framework to study variability in plant mechanosensing and demonstrated interspecific variability in mechanosensing.  
  Address [Coutand, Catherine; Lacointe, Andre] Univ Clermont Ferrand, INRA, PIAF, UMR 547, F-63000 Clermont Ferrand, France, Email: coutand@clermont.inra.fr  
  Corporate Author Thesis  
  Publisher OXFORD UNIV PRESS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0305-7364 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274347000025 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 71  
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Author Baraloto, C.; Paine, C.E.T.; Patino, S.; Bonal, D.; Herault, B.; Chave, J. openurl 
  Title Functional trait variation and sampling strategies in species-rich plant communities Type Journal Article
  Year (down) 2010 Publication Functional Ecology Abbreviated Journal Funct. Ecol.  
  Volume 24 Issue 1 Pages 208-216  
  Keywords French Guiana; functional diversity; plant traits; specific leaf area; wood density; sampling design; tropical forest  
  Abstract P> Despite considerable interest in the application of plant functional traits to questions of community assembly and ecosystem structure and function, there is no consensus on the appropriateness of sampling designs to obtain plot-level estimates in diverse plant communities. We measured 10 plant functional traits describing leaf and stem morphology and ecophysiology for all trees in nine 1-ha plots in terra firme lowland tropical rain forests of French Guiana (N = 4709). We calculated, by simulation, the mean and variance in trait values for each plot and each trait expected under seven sampling methods and a range of sampling intensities. Simulated sampling methods included a variety of spatial designs, as well as the application of existing data base values to all individuals of a given species. For each trait in each plot, we defined a performance index for each sampling design as the proportion of resampling events that resulted in observed means within 5% of the true plot mean, and observed variance within 20% of the true plot variance. The relative performance of sampling designs was consistent for estimations of means and variances. Data base use had consistently poor performance for most traits across all plots, whereas sampling one individual per species per plot resulted in relatively high performance. We found few differences among different spatial sampling strategies; however, for a given strategy, increased intensity of sampling resulted in markedly improved accuracy in estimates of trait mean and variance. We also calculated the financial cost of each sampling design based on data from our 'every individual per plot' strategy and estimated the sampling and botanical effort required. The relative performance of designs was strongly positively correlated with relative financial cost, suggesting that sampling investment returns are relatively constant. Our results suggest that trait sampling for many objectives in species-rich plant communities may require the considerable effort of sampling at least one individual of each species in each plot, and that investment in complete sampling, though great, may be worthwhile for at least some traits.  
  Address [Baraloto, Christopher; Patino, Sandra; Bonal, Damien] INRA, UMR Ecol Forets Guyane, F-97387 Kourou, French Guiana, Email: chris.baraloto@ecofog.gf  
  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 0269-8463 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000273455500024 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 72  
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Author Cabanillas, B.J.; Le Lamer, A.C.; Castillo, D.; Arevalo, J.; Rojas, R.; Odonne, G.; Bourdy, G.; Moukarzel, B.; Sauvain, M.; Fabre, N. openurl 
  Title Caffeic Acid Esters and Lignans from Piper sanguineispicum Type Journal Article
  Year (down) 2010 Publication Journal of Natural Products Abbreviated Journal J. Nat. Prod.  
  Volume 73 Issue 11 Pages 1884-1890  
  Keywords  
  Abstract Three new caffeic acid esters (1-3), four new lignans (4-7), and the known compounds (7'S)-parabenzlactone (8), dihydrocubebin (9), and justiflorinol (10) have been isolated from leaves of Piper sanguineispicum. Their structures were determined by spectroscopic methods, including 1D and 2D NMR, HRCIMS, CD experiments, and chemical methods. Compounds 1-10 were assessed for their antileishmanial potential against axenic amastigote forms of Leishmania amazonensis. Caffeic acid esters 1 and 3 exhibited the best antileishmanial activity (IC50 2.0 and 1.8 μM, respectively) with moderate cytotoxicity on murine macrophages.  
  Address [Cabanillas, Billy Joel; Le Lamer, Anne-Cecile; Odonne, Guillaume; Bourdy, Genevieve; Moukarzel, Beatrice; Sauvain, Michel; Fabre, Nicolas] Univ Toulouse, UPS, UMR 152, Lab Pharmacochim Subst Nat & Pharmacophores Redox, F-31062 Toulouse 9, France, Email: michel.sauvain@ird.fr  
  Corporate Author Thesis  
  Publisher AMER CHEMICAL SOC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-3864 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000284559100024 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 74  
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Author Dejean, A.; Leroy, C.; Corbara, B.; Cereghino, R.; Roux, O.; Herault, B.; Rossi, V.; Guerrero, R.J.; Delabie, J.H.C.; Orivel, J.; Boulay, R. openurl 
  Title A temporary social parasite of tropical plant-ants improves the fitness of a myrmecophyte Type Journal Article
  Year (down) 2010 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften  
  Volume 97 Issue 10 Pages 925-934  
  Keywords Ant-plant relationships; Biotic defense; Parasites of mutualisms; Temporary social parasites; Azteca; Cecropia  
  Abstract Myrmecophytes offer plant-ants a nesting place in exchange for protection from their enemies, particularly defoliators. These obligate ant-plant mutualisms are common model systems for studying factors that allow horizontally transmitted mutualisms to persist since parasites of ant-myrmecophyte mutualisms exploit the rewards provided by host plants whilst providing no protection in return. In pioneer formations in French Guiana, Azteca alfari and Azteca ovaticeps are known to be mutualists of myrmecophytic Cecropia (Cecropia ants). Here, we show that Azteca andreae, whose colonies build carton nests on myrmecophytic Cecropia, is not a parasite of Azteca-Cecropia mutualisms nor is it a temporary social parasite of A. alfari; it is, however, a temporary social parasite of A. ovaticeps. Contrarily to the two mutualistic Azteca species that are only occasional predators feeding mostly on hemipteran honeydew and food bodies provided by the host trees, A. andreae workers, which also attend hemipterans, do not exploit the food bodies. Rather, they employ an effective hunting technique where the leaf margins are fringed with ambushing workers, waiting for insects to alight. As a result, the host trees' fitness is not affected as A. andreae colonies protect their foliage better than do mutualistic Azteca species resulting in greater fruit production. Yet, contrarily to mutualistic Azteca, when host tree development does not keep pace with colony growth, A. andreae workers forage on surrounding plants; the colonies can even move to a non-Cecropia tree.  
  Address [Dejean, Alain; Leroy, Celine; Roux, Olivier; Orivel, Jerome] CNRS, 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:000282094100006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 77  
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Author Foucaud, J.; Estoup, A.; Loiseau, A.; Rey, O.; Orivel, J. openurl 
  Title Thelytokous parthenogenesis, male clonality and genetic caste determination in the little fire ant: new evidence and insights from the lab Type Journal Article
  Year (down) 2010 Publication Heredity Abbreviated Journal Heredity  
  Volume 105 Issue 2 Pages 205-212  
  Keywords reproduction system; thelytokous parthenogenesis; male clonality; genetic caste determination; Wasmannia auropunctata  
  Abstract Previous studies indicate that some populations of the little fire ant, Wasmannia auropunctata, display an unusual reproduction system polymorphism. Although some populations have a classical haplodiploid reproduction system, in other populations queens are produced by thelytokous parthenogenesis, males are produced by a male clonality system and workers are produced sexually. An atypical genetic caste determination system was also suggested. However, these conclusions were indirectly inferred from genetic studies on field population samples. Here we set up experimental laboratory nests that allow the control of the parental relationships between individuals. The queens heading those nests originated from either putatively clonal or sexual populations. We characterized the male, queen and worker offspring they produced at 12 microsatellite loci. Our results unambiguously confirm the unique reproduction system polymorphism mentioned above and that male clonality is strictly associated with thelytokous parthenogenesis. We also observed direct evidence of the rare production of sexual gynes and arrhenotokous males in clonal populations. Finally, we obtained evidence of a genetic basis for caste determination. The evolutionary significance of the reproduction system polymorphism and genetic caste determination as well as future research opportunities are discussed. Heredity (2010) 105, 205-212; doi: 10.1038/hdy.2009.169; published online 25 November 2009  
  Address [Foucaud, J.; Estoup, A.; Loiseau, A.; Rey, O.] INRA, UMR CBGP, IRD, Cirad,Montpellier SupAgro, Montferrier Sur Lez, France, Email: julien.foucaud@legs.cnrs-gif.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:000280111800007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 78  
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Author Foucaud, J.; Orivel, J.; Loiseau, A.; Delabie, J.H.C.; Jourdan, H.; Konghouleux, D.; Vonshak, M.; Tindo, M.; Mercier, J.L.; Fresneau, D.; Mikissa, J.B.; McGlynn, T.; Mikheyev, A.S.; Oettler, J.; Estoup, A. openurl 
  Title Worldwide invasion by the little fire ant: routes of introduction and eco-evolutionary pathways Type Journal Article
  Year (down) 2010 Publication Evolutionary Applications Abbreviated Journal Evol. Appl.  
  Volume 3 Issue 4 Pages 363-374  
  Keywords biological invasion; introduction routes; parthenogenesis; reproduction system; Wasmannia auropunctata  
  Abstract Biological invasions are generally thought to occur after human aided migration to a new range. However, human activities prior to migration may also play a role. We studied here the evolutionary genetics of introduced populations of the invasive ant Wasmannia auropunctata at a worldwide scale. Using microsatellite markers, we reconstructed the main routes of introduction of the species. We found three main routes of introduction, each of them strongly associated to human history and trading routes. We also demonstrate the overwhelming occurrence of male and female clonality in introduced populations of W. auropunctata, and suggest that this particular reproduction system is under selection in human-modified habitats. Together with previous researches focused on native populations, our results suggest that invasive clonal populations may have evolved within human modified habitats in the native range, and spread further from there. The evolutionarily most parsimonious scenario for the emergence of invasive populations of the little fire ant might thus be a two-step process. The W. auropunctata case illustrates the central role of humans in biological change, not only due to changes in migration patterns, but also in selective pressures over species.  
  Address [Foucaud, Julien; Loiseau, Anne; Jourdan, Herve; Konghouleux, Djoel; Estoup, Arnaud] Montpellier SupAgro, INRA, UMR CBGP, IRD,Cirad, 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 1752-4571 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000278913600004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 79  
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Author Bekaert, E.; Robert, F.; Lippens, P.E.; Menetrier, M. openurl 
  Title Li-7 NMR Knight Shifts in Li-Sn Compounds: MAS NMR Measurements and Correlation with DFT Calculations Type Journal Article
  Year (down) 2010 Publication Journal of Physical Chemistry C Abbreviated Journal J. Phys. Chem. C  
  Volume 114 Issue 14 Pages 6749-6754  
  Keywords  
  Abstract Several Li-Sn crystalline phases, LiSn. Li7Sn3, Li5Sn7, Li13Sn5, Li7Sn2, and Li22Sn5. were prepared by ball-milling and studied by Li-7 MAS NMR spectroscopy with silica as a chiming agent to avoid field penetration limitations All phases except for LiSn exhibit exchanged NMR signals at room temperature for the various types of Li present in the unit cells. in the 10 to 100 ppm range. Electronic structure calculations based on first-principles method led to a lather good correlation between the participation of the Li 2s orbital to the density of states (DOS) at the Fermi level and the corresponding NMR Knight shift for the two Li crystallographic types in the case of LiSn, and for the weighted average of the different crystallographic types in the case of the NMR-exchanged signals for the other compounds  
  Address [Bekaert, Emilie; Menetrier, Michel] Univ Bordeaux, CNRS, ICMCB, F-33608 Pessac, France  
  Corporate Author Thesis  
  Publisher AMER CHEMICAL SOC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000276341700075 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 80  
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Author Dejean, A.; Fisher, B.L.; Corbara, B.; Rarevohitra, R.; Randrianaivo, R.; Rajemison, B.; Leponce, M. pdf  openurl
  Title Spatial Distribution of Dominant Arboreal Ants in a Malagasy Coastal Rainforest: Gaps and Presence of an Invasive Species Type Journal Article
  Year (down) 2010 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 5 Issue 2 Pages e9319  
  Keywords  
  Abstract We conducted a survey along three belt transects located at increasing distances from the coast to determine whether a non-random arboreal ant assemblage, such as an ant mosaic, exists in the rainforest on the Masoala Peninsula, Madagascar. In most tropical rainforests, very populous colonies of territorially dominant arboreal ant species defend absolute territories distributed in a mosaic pattern. Among the 29 ant species recorded, only nine had colonies large enough to be considered potentially territorially dominant; the remaining species had smaller colonies and were considered non-dominant. Nevertheless, the null-model analyses used to examine the spatial structure of their assemblages did not reveal the existence of an ant mosaic. Inland, up to 44% of the trees were devoid of dominant arboreal ants, something not reported in other studies. While two Crematogaster species were not associated with one another, Brachymyrmex cordemoyi was positively associated with Technomyrmex albipes, which is considered an invasive species-a non-indigenous species that has an adverse ecological effect on the habitats it invades. The latter two species and Crematogaster ranavalonae were mutually exclusive. On the other hand, all of the trees in the coastal transect and at least 4 km of coast were occupied by T. albipes, and were interconnected by columns of workers. Technomyrmex albipes workers collected from different trees did not attack each other during confrontation tests, indicating that this species has formed a supercolony along the coast. Yet interspecific aggressiveness did occur between T. albipes and Crematogaster ranavalonae, a native species which is likely territorially dominant based on our intraspecific confrontation tests. These results suggest that the Masoala rainforest is threatened by a potential invasion by T. albipes, and that the penetration of this species further inland might be facilitated by the low density of native, territorially dominant arboreal ants normally able to limit its progression.  
  Address [Dejean, Alain] CNRS, Unite Mixte Rech 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:000274923700021 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 81  
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Author Roux, O.; Billen, J.; Orivel, J.; Dejean, A. pdf  openurl
  Title An Overlooked Mandibular-Rubbing Behavior Used during Recruitment by the African Weaver Ant, Oecophylla longinoda Type Journal Article
  Year (down) 2010 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 5 Issue 2 Pages e8957  
  Keywords  
  Abstract In Oecophylla, an ant genus comprising two territorially dominant arboreal species, workers are known to (1) use anal spots to mark their territories, (2) drag their gaster along the substrate to deposit short-range recruitment trails, and (3) drag the extruded rectal gland along the substrate to deposit the trails used in long-range recruitment. Here we study an overlooked but important marking behavior in which O. longinoda workers first rub the underside of their mandibles onto the substrate, and then-in a surprising posture-tilt their head and also rub the upper side of their mandibles. We demonstrate that this behavior is used to recruit nestmates. Its frequency varies with the rate at which a new territory, a sugary food source, a prey item, or an alien ant are discovered. Microscopy analyses showed that both the upper side and the underside of the mandibles possess pores linked to secretory glands. So, by rubbing their mandibles onto the substrate, the workers probably spread a secretion from these glands that is involved in nestmate recruitment.  
  Address [Roux, Olivier; Dejean, Alain] CNRS, UMR, Kourou, France, Email: oroux@cict.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:000274209700003 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 82  
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