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Author Malé, P.-J.G.; Leroy, C.; Humblot, P.; Dejean, A.; Quilichini, A.; Orivel, J. doi  openurl
  Title Limited gene dispersal and spatial genetic structure as stabilizing factors in an ant-plant mutualism Type Journal Article
  Year 2016 Publication Journal of Evolutionary Biology Abbreviated Journal J. Evol. Biol.  
  Volume 29 Issue 12 Pages 2519-2529  
  Keywords gene flow; local adaptation; metapopulation; myrmecophyte; population genetics  
  Abstract Comparative studies of the population genetics of closely associated species are necessary to properly understand the evolution of these relationships because gene flow between populations affects the partners' evolutionary potential at the local scale. As a consequence (at least for antagonistic interactions), asymmetries in the strength of the genetic structures of the partner populations can result in one partner having a co-evolutionary advantage. Here, we assess the population genetic structure of partners engaged in a species-specific and obligatory mutualism: the Neotropical ant-plant, Hirtella physophora, and its ant associate, Allomerus decemarticulatus. Although the ant cannot complete its life cycle elsewhere than on H. physophora and the plant cannot live for long without the protection provided by A. decemarticulatus, these species also have antagonistic interactions: the ants have been shown to benefit from castrating their host plant and the plant is able to retaliate against too virulent ant colonies. We found similar short dispersal distances for both partners, resulting in the local transmission of the association and, thus, inbred populations in which too virulent castrating ants face the risk of local extinction due to the absence of H. physophora offspring. On the other hand, we show that the plant populations probably experienced greater gene flow than did the ant populations, thus enhancing the evolutionary potential of the plants. We conclude that such levels of spatial structure in the partners' populations can increase the stability of the mutualistic relationship. Indeed, the local transmission of the association enables partial alignments of the partners' interests, and population connectivity allows the plant retaliation mechanisms to be locally adapted to the castration behaviour of their symbionts.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1420-9101 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial (up) 710  
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Author Talaga, S.; Leroy, C.; Céréghino, R.; Dejean, A. doi  openurl
  Title Convergent evolution of intraguild predation in phytotelm-inhabiting mosquitoes Type Journal Article
  Year 2016 Publication Evolutionary Ecology Abbreviated Journal Evol. Ecol.  
  Volume 30 Issue 6 Pages 1133-1147  
  Keywords  
  Abstract Intraguild predation (IGP) is a type of biological interaction involving the killing and consuming of competing species that exploit similar and often limited resources. This phenomenon is widespread among a great variety of taxonomic groups and has already been reported for mosquito (Diptera: Culicidae) larvae. Moreover, the larvae of certain mosquito species of the tribe Sabethini have evolved modified mouthparts ending in rigid apical structures signaling their capacity to be effective intraguild predators. We assumed that IGP confers a selective advantage under severe competitive conditions by both providing an immediate energetic gain and reducing potential competition. Because potential competition is likely to increase with decreasing habitat size, we hypothesized that the proportion of species with modified mouthparts would increase in smaller aquatic habitats. We tested this hypothesis by examining the mosquito species naturally associated with phytotelmata of decreasing sizes in French Guiana. We show that the degree of specialization in mosquito-phytotelm associations is high, suggesting a long coevolutive process. Indeed, short-term interaction experiments confirmed that species with modified mouthparts are able to prey upon similarly-sized intraguild prey and are, thus, effective intraguild predators. In addition, these species are larger and associated with smaller phytotelmata than those with typical mouthparts. Moreover, below a certain threshold of phytotelm size, only species with modified mouthparts were present. These results show that IGP confers a selective advantage under severe competitive conditions and results from the coadaptation of mosquito species to their specific phytotelm habitat. The presence of functionally analogous structures in different mosquito genera also implies that IGP has emerged from convergent evolution in small phytotelmata.  
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  Series Volume Series Issue Edition  
  ISSN 1573-8477 ISBN Medium  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Talaga2016 Serial (up) 711  
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Author Leroy, C.; Petitclerc, F.; Orivel, J.; Corbara, B.; Carrias, J.-F.; Dejean, A.; Céréghino, R. doi  openurl
  Title The influence of light, substrate and seed origin on the germination and establishment of an ant-garden bromeliad Type Journal Article
  Year 2017 Publication Plant Biology Abbreviated Journal Plant Biol J  
  Volume 19 Issue 1 Pages 70-78  
  Keywords Aechmea mertensii; bromeliad; French Guiana; germination; plant performance; survival  
  Abstract Plant germination and development depend upon a seed's successful dispersal into a suitable habitat and its ability to grow and survive within the surrounding biotic and abiotic environment. The seeds of Aechmea mertensii, a tank-bromeliad species, are dispersed by either Camponotus femoratus or Neoponera goeldii, two ant species that initiate ant gardens (AGs). These two mutualistic ant species influence the vegetative and reproductive traits of the bromeliad through their divergent ecological preferences (i.e. light and substrate). We hypothesised that the seeds dispersed by these two ant species have underlying genetic differences affecting germination, growth and survival of A. mertensii seedlings in different ways. To test this, we used an experimental approach consisting of sowing seeds of A. mertensii: (i) taken from the two AG–ant associations (i.e. seed origin), (ii) in two contrasting light conditions, and (iii) on three different substrates. Light and substrate had significant effects on germination, survival and on eight key leaf traits reflecting plant performance. Seed origin had a significant effect only on germination and on two leaf traits (total dry mass and relative growth rate). Overall, this bromeliad performs better (i.e. high growth and survival rates) when growing both in the shade and in the carton nest developed by C. femoratus ants. These results suggest that the plasticity of the tank bromeliad A. mertensii is mainly due to environment but also to genetic differences related to seed origin, as some traits are heritable. Thus, these two ant species may play contrasting roles in shaping plant evolution and speciation.  
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  Series Volume Series Issue Edition  
  ISSN 1438-8677 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial (up) 712  
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Author Courtois, E.A.; Dexter, K.G.; Paine, C.E.T.; Stien, D.; Engel, J.; Baraloto, C.; Chave, J. pdf  doi
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  Title Evolutionary patterns of volatile terpene emissions across 202 tropical tree species Type Journal Article
  Year 2016 Publication Ecology and Evolution Abbreviated Journal Ecol Evol  
  Volume 6 Issue 9 Pages 2854-2864  
  Keywords Chemical defense; French Guiana; herbivory; secondary metabolites; tropical forest  
  Abstract Plant responses to natural enemies include formation of secondary metabolites acting as direct or indirect defenses. Volatile terpenes represent one of the most diverse groups of secondary metabolites. We aimed to explore evolutionary patterns of volatile terpene emission. We measured the composition of damage-induced volatile terpenes from 202 Amazonian tree species, spanning the angiosperm phylogeny. Volatile terpenes were extracted with solid-phase micro extraction and desorbed in a gas chromatography–mass spectrometry for compound identification. The chemical diversity of the terpene blend showed a strong phylogenetic signal as closely related species emitted a similar number of compounds. Closely related species also tended to have compositionally similar blends, although this relationship was weak. Meanwhile, the ability to emit a given compound showed no significant phylogenetic signal for 200 of 286 compounds, indicating a high rate of diversification in terpene synthesis and/or great variability in their expression. Three lineages (Magnoliales, Laurales, and Sapindales) showed exceptionally high rates of terpene diversification. Of the 70 compounds found in >10% of their species, 69 displayed significant correlated evolution with at least one other compound. These results provide insights into the complex evolutionary history of volatile terpenes in angiosperms, while highlighting the need for further research into this important class of compounds.  
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  Series Volume Series Issue Edition  
  ISSN 2045-7758 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial (up) 713  
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Author Denis, T.; Herault, B.; Jaouen, G.; Brunaux, O.; Guitet, S.; Richard-Hansen, C. doi  openurl
  Title Black Curassow habitat relationships in terra firme forests of the Guiana Shield: A multiscale approach Type Journal Article
  Year 2016 Publication The Condor Abbreviated Journal The Condor  
  Volume 118 Issue 2 Pages 253-273  
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  Abstract ABSTRACT The Black Curassow (Crax alector) is a large game bird with Vulnerable conservation status found in north-central South America. We examined its distributional pattern across French Guiana using a large number of environmental descriptors at 3 scales of analysis: landscape, forest type, and microhabitat. We used a hierarchical model with temporary emigration and imperfect detection for data collected by standard distance sampling methods at 35 study sites. At the landscape scale, Black Curassow density decreased with hunting pressure and increased with steeper slopes in both hunted and unhunted areas. Topography appeared to be a good proxy for Black Curassow ecological requirements and probably reflected habitat quality. At the forest scale, population density was negatively correlated with the abundance of palms and Mimosoideae and positively correlated with the abundance of Lauraceae. Botanical families did not directly influence Black Curassow distribution, but rather determined spatial patterns by being markers of a particular forest type. At the microhabitat scale, Black Curassows used hilltops more frequently than other parts of the local topographical gradient. Our multiscale analysis shows that this species' distribution can be explained by biotic or abiotic conditions, regardless of the scale. For conservation, we recommend maintaining connectivity between Black Curassow populations separated by hunted areas. Our predicted densities could be used to adapt hunting quotas across French Guiana's forests. We show that combining field and remote sensing data helps to understand the ecological processes responsible for Black Curassow habitat relationships.  
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  Publisher American Ornithological Society Place of Publication Editor  
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  Series Volume Series Issue Edition  
  ISSN 0010-5422 ISBN Medium  
  Area Expedition Conference  
  Notes doi: 10.1650/CONDOR-15-28.1 Approved no  
  Call Number EcoFoG @ webmaster @ Serial (up) 714  
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Author Salas-Lopez, A.; Mickal, H.; Menzel, F.; Orivel, J. doi  openurl
  Title Ant-mediated ecosystem processes are driven by trophic community structure but mainly by the environment Type Journal Article
  Year 2017 Publication Oecologia Abbreviated Journal Oecologia  
  Volume 183 Issue 1 Pages 249-261  
  Keywords  
  Abstract The diversity and functional identity of organisms are known to be relevant to the maintenance of ecosystem processes but can be variable in different environments. Particularly, it is uncertain whether ecosystem processes are driven by complementary effects or by dominant groups of species. We investigated how community structure (i.e., the diversity and relative abundance of biological entities) explains the community-level contribution of Neotropical ant communities to different ecosystem processes in different environments. Ants were attracted with food resources representing six ant-mediated ecosystem processes in four environments: ground and vegetation strata in cropland and forest habitats. The exploitation frequencies of the baits were used to calculate the taxonomic and trophic structures of ant communities and their contribution to ecosystem processes considered individually or in combination (i.e., multifunctionality). We then investigated whether community structure variables could predict ecosystem processes and whether such relationships were affected by the environment. We found that forests presented a greater biodiversity and trophic complementarity and lower dominance than croplands, but this did not affect ecosystem processes. In contrast, trophic complementarity was greater on the ground than on vegetation and was followed by greater resource exploitation levels. Although ant participation in ecosystem processes can be predicted by means of trophic-based indices, we found that variations in community structure and performance in ecosystem processes were best explained by environment. We conclude that determining the extent to which the dominance and complementarity of communities affect ecosystem processes in different environments requires a better understanding of resource availability to different species.  
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  ISSN 1432-1939 ISBN Medium  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Salas-Lopez2017 Serial (up) 715  
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Author Dezerald, O.; Leroy, C.; Corbara, B.; Dejean, A.; Talaga, S.; Céréghino, R. doi  openurl
  Title Environmental drivers of invertebrate population dynamics in Neotropical tank bromeliads Type Journal Article
  Year 2017 Publication Freshwater Biology Abbreviated Journal Freshw Biol  
  Volume 62 Issue 2 Pages 229-242  
  Keywords food webs; freshwater invertebrates; growth rate; life history; rainforest  
  Abstract Tank bromeliads form a conspicuous, yet neglected freshwater habitat in Neotropical forests. Recent studies driven by interests in medical entomology, fundamental aspects of bromeliad ecology and experimental research on food webs have, however, prompted increasing interest in bromeliad aquatic ecosystems. As yet, there is nothing in the literature about the life histories and environmental drivers of invertebrate population dynamics in tank bromeliads.

Based on fortnightly samples taken over one year, size frequency plots and individual dry masses allowed us to establish the life cycles and growth rates of the dominant aquatic invertebrates in a common bromeliad species of French Guiana. Linear mixed-effect models and Mantel tests were used to predict changes in density, biomass, and growth rates in relation to temperature, rainfall, humidity and detrital resources.

Annual variations in invertebrate densities and biomasses could be described according to three types of distribution: unimodal, bimodal or almost constant. Despite seasonal variations, precipitation, temperature, relative humidity and detritus concentration accounted significantly for changes in density and biomass, but we found no significant responses in growth rates of most invertebrate species. Species rather displayed non-seasonal life cycles with overlapping cohorts throughout the year. There was also a trend for delayed abundance peaks among congeneric species sharing similar functional traits, suggesting temporal partitioning of available resources.

Beyond novel knowledge, quantitative information on life histories is important to predict food-web dynamics under the influence of external forcing and self-organisation. Our results suggest that changes in species distribution that will affect population dynamics through biotic interactions in space and/or time could have greater effects on food webs and ecosystem functioning than changes in environmental factors per se.
 
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1365-2427 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial (up) 716  
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Author Dejean, A.; Azémar, F.; Libert, M.; Compin, A.; Herault, B.; Orivel, J.; Bouyer, T.; Corbara, B. doi  openurl
  Title Ant-lepidopteran associations along African forest edges Type Journal Article
  Year 2017 Publication The Science of Nature Abbreviated Journal  
  Volume 104 Issue 1 Pages 7  
  Keywords  
  Abstract Working along forest edges, we aimed to determine how some caterpillars can co-exist with territorially dominant arboreal ants (TDAAs) in tropical Africa. We recorded caterpillars from 22 lepidopteran species living in the presence of five TDAA species. Among the defoliator and/or nectarivorous caterpillars that live on tree foliage, the Pyralidae and Nymphalidae use their silk to protect themselves from ant attacks. The Notodontidae and lycaenid Polyommatinae and Theclinae live in direct contact with ants; the Theclinae even reward ants with abundant secretions from their Newcomer gland. Lichen feeders (lycaenid; Poritiinae), protected by long bristles, also live among ants. Some lycaenid Miletinae caterpillars feed on ant-attended membracids, including in the shelters where the ants attend them; Lachnocnema caterpillars use their forelegs to obtain trophallaxis from their host ants. Caterpillars from other species live inside weaver ant nests. Those of the genus Euliphyra (Miletinae) feed on ant prey and brood and can obtain trophallaxis, while those from an Eberidae species only prey on host ant eggs. Eublemma albifascia (Erebidae) caterpillars use their thoracic legs to obtain trophallaxis and trophic eggs from ants. Through transfer bioassays of last instars, we noted that herbivorous caterpillars living in contact with ants were always accepted by alien conspecific ants; this is likely due to an intrinsic appeasing odor. Yet, caterpillars living in ant shelters or ant nests probably acquire cues from their host colonies because they were considered aliens and killed. We conclude that co-evolution with ants occurred similarly in the Heterocera and Rhopalocera.  
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  Series Volume Series Issue Edition  
  ISSN 1432-1904 ISBN Medium  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Dejean2016 Serial (up) 717  
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Author Ghislain, B.; Nicolini, E.-A.; Romain, R.; Ruelle, J.; Yoshinaga, A.; Alford, M.H.; Clair, B. doi  openurl
  Title Multilayered structure of tension wood cell walls in Salicaceae sensu lato and its taxonomic significance Type Journal Article
  Year 2016 Publication Botanical Journal of the Linnean Society Abbreviated Journal Bot. J. Linn. Soc.  
  Volume 182 Issue 4 Pages 744-756  
  Keywords Flacourtiaceae; G-layer; multilayered tension wood; reaction wood  
  Abstract Salicaceae have been enlarged to include a majority of the species formerly placed in the polyphyletic tropical Flacourtiaceae. Several studies have reported a peculiar and infrequently formed multilayered structure of tension wood in four of the tropical genera. Tension wood is a tissue produced by trees to restore their vertical orientation and most studies have focused on trees developing tension wood by means of cellulose-rich, gelatinous fibres, as in Populus and Salix (Salicaceae s.s.). This study aims to determine if the multilayered structure of tension wood is an anatomical characteristic common in other Salicaceae and, if so, how its distribution correlates to phylogenetic relationships. Therefore, we studied the tension wood of 14 genera of Salicaceae and two genera of Achariaceae, one genus of Goupiaceae and one genus of Lacistemataceae, families closely related to Salicaceae or formerly placed in Flacourtiaceae. Opposite wood and tension wood were compared with light microscopy and three-dimensional laser scanning confocal microscopy. The results indicate that a multilayered structure of tension wood is common in the family except in Salix, Populus and one of their closest relatives, Idesia polycarpa. We suggest that tension wood may be a useful anatomical character in understanding phylogenetic relationships in Salicaceae. Further investigation is still needed on the tension wood of several other putatively close relatives of Salix and Populus, in particular Bennettiodendron, Macrohasseltia and Itoa.  
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  Series Volume Series Issue Edition  
  ISSN 1095-8339 ISBN Medium  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial (up) 718  
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Author Alméras, T.; Clair, B. url  openurl
  Title Critical review on the mechanisms of maturation stress generation in trees Type Journal Article
  Year 2016 Publication Journal of the Royal Society Interface Abbreviated Journal J R Soc Interface  
  Volume 13 Issue 122 Pages  
  Keywords  
  Abstract Trees control their posture by generating asymmetric mechanical stress around the periphery of the trunk or branches. This stress is produced in wood during the maturation of the cell wall. When the need for reaction is high, it is accompanied by strong changes in cell organization and composition called reaction wood, namely compression wood in gymnosperms and tension wood in angiosperms. The process by which stress is generated in the cell wall during its formation is not yet known, and various hypothetical mechanisms have been proposed in the literature. Here we aim at discriminating between these models. First, we summarize current knowledge about reaction wood structure, state and behaviour relevant to the understanding of maturation stress generation. Then, the mechanisms proposed in the literature are listed and discussed in order to identify which can be rejected based on their inconsistency with current knowledge at the frontier between plant science and mechanical engineering.  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial (up) 719  
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