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Auteur Mason, N.W.H.; de Bello, F.; Mouillot, D.; Pavoine, S.; Dray, S. url  doi
openurl 
  Titre (up) A guide for using functional diversity indices to reveal changes in assembly processes along ecological gradients Type Article scientifique
  Année 2013 Publication Revue Abrégée J Veg Sci  
  Volume 24 Numéro 5 Pages 794-806  
  Mots-Clés Co-existence; Environmental filtering; Functional divergence; Functional evenness; Functional richness; Functional trait; Limiting similarity; Niche complementarity; Null models; species richness  
  Résumé Question Which functional diversity indices have the power to reveal changes in community assembly processes along abiotic stress gradients? Is their power affected by stochastic processes and variations in species richness along stress gradients?

Methods We used a simple community assembly model to explore the power of functional diversity indices across a wide range of ecological contexts. FD) and convex hull volume (FRic) – with a matrix-swap null model (yielding indices SESFD and SESFRic) to remove any trivial effects of species richness. We also compared two indices that measure both functional richness and functional divergence – Rao quadratic entropy (Rao) and functional dispersion (FDis) – with a null model that randomizes abundances across species but within communities. SESRao and SESFDis).

Results When mass effects operated, only SESRao and SESFDis gave reasonable power, irrespective of how species richness varied along the stress gradient. FD, FRic, Rao and FDis had low power when species richness was constant, and variation in species richness greatly influenced their power. SESFRic and SESFD were unaffected by variation in species richness. When priority effects operated, FRic, SESFRic, Rao and FDis had good power and were unaffected by variation in species richness. Variation in species richness greatly affected FD and SESFD. SESRao and SESFDis had low power in the priority effects model but were unaffected by variation in species richness.

Conclusions Our results demonstrate that a reliable test for changes in assembly processes along stress gradients requires functional diversity indices measuring either functional richness or functional divergence. We recommend using SESFRic as a measure of functional richness and either SESRao or SESFDis (which are very closely related mathematically) as a measure of functional divergence. Used together, these indices of functional richness and functional divergence provide good power to test for increasing niche complementarity with declining stress across a broad range of ecological contexts.
 
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 1654-1103 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 406  
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Auteur Meynard, C.N.; Mouillot, D.; Mouquet, N.; Douzery, E.J.P. url  doi
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  Titre (up) A Phylogenetic Perspective on the Evolution of Mediterranean Teleost Fishes Type Article scientifique
  Année 2012 Publication Revue Abrégée PLoS One  
  Volume 7 Numéro 5 Pages  
  Mots-Clés cytochrome-b; divergence time; diversification; dna sequences; missing data; mitochondrial genome sequences; molecular phylogeny; nuclear; ray-finned fishes; tetraodontiform fishes  
  Résumé The Mediterranean Sea is a highly diverse, highly studied, and highly impacted biogeographic region, yet no phylogenetic reconstruction of fish diversity in this area has been published to date. Here, we infer the timing and geographic origins of Mediterranean teleost species diversity using nucleotide sequences collected from GenBank. We assembled a DNA supermatrix composed of four mitochondrial genes (12S ribosomal DNA, 16S ribosomal DNA, cytochrome c oxidase subunit I and cytochrome b) and two nuclear genes (rhodopsin and recombination activating gene I), including 62% of Mediterranean teleost species plus 9 outgroups. Maximum likelihood and Bayesian phylogenetic and dating analyses were calibrated using 20 fossil constraints. An additional 124 species were grafted onto the chronogram according to their taxonomic affinity, checking for the effects of taxonomic coverage in subsequent diversification analyses. We then interpreted the time-line of teleost diversification in light of Mediterranean historical biogeography, distinguishing non-endemic natives, endemics and exotic species. Results show that the major Mediterranean orders are of Cretaceous origin, specifically similar to 100-80 Mya, and most Perciformes families originated 80-50 Mya. Two important clade origin events were detected. The first at 100-80 Mya, affected native and exotic species, and reflects a global diversification period at a time when the Mediterranean Sea did not yet exist. The second occurred during the last 50 Mya, and is noticeable among endemic and native species, but not among exotic species. This period corresponds to isolation of the Mediterranean from Indo-Pacific waters before the Messinian salinity crisis. The Mediterranean fish fauna illustrates well the assembly of regional faunas through origination and immigration, where dispersal and isolation have shaped the emergence of a biodiversity hotspot.  
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  ISSN 1932-6203 ISBN Médium  
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Auteur ARNAUD-HAOND, S.; MOALIC, Y.; HERNANDEZ-GARCIA, E.; EGUILUZ, V.M.; ALBERTO, F.; SERRAO, E.A.; DUARTE, C.M. url  openurl
  Titre (up) Disentangling the Influence of Mutation and Migration in Clonal Seagrasses Using the Genetic Diversity Spectrum for Microsatellites Type Article scientifique
  Année 2014 Publication Revue Abrégée Journal Of Heredity  
  Volume 105 Numéro 4 Pages 532-541  
  Mots-Clés clonality; genetic divergence; Genetic Diversity Spectrum; microsatellites; Seagrass; stepwise mutation  
  Résumé The recurrent lack of isolation by distance reported at regional scale in seagrass species was recently suggested to stem from stochastic events of large-scale dispersal. We explored the usefulness of phylogenetic information contained in microsatellite loci to test this hypothesis by using the Genetic Diversity Spectrum (GDS) on databases containing, respectively, 7 and 9 microsatellites genotypes for 1541 sampling units of Posidonia oceanica and 1647 of Cymodocea nodosa. The simultaneous increase of microsatellite and geographic distances that emerges reveals a coherent pattern of isolation by distance in contrast to the chaotic pattern previously described using allele frequencies, in particular, for the long-lived P. oceanica. These results suggest that the lack of isolation by distance, rather than the resulting from rare events of large-scale dispersal, reflects at least for some species a stronger influence of mutation over migration at the scale of the distribution range. The global distribution of genetic polymorphism may, therefore, result predominantly from ancient events of step-by-step (re)colonization followed by local recruitment and clonal growth, rather than contemporary gene flow. The analysis of GDS appears useful to unravel the evolutionary forces influencing the dynamics and evolution at distinct temporal and spatial scales by accounting for phylogenetic information borne by microsatellites, under an appropriate mutation model. This finding adds nuance to the generalization of the influence of large-scale dispersal on the dynamics of seagrasses.  
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  ISSN 0022-1503 ISBN Médium  
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Auteur Tran, T.T.V.; Phan, L.K.; Durand, J.-D. doi  openurl
  Titre (up) Diversity and distribution of cryptic species within the Mugil cephalus species complex in Vietnam Type Article scientifique
  Année 2017 Publication Revue Abrégée Mitochondrial DNA Part A  
  Volume 28 Numéro 4-5 Pages 493-501  
  Mots-Clés Cryptic species; cytochrome b; cytochrome oxidase I; divergence; genetic diversity; marginal seas; mitochondrial phylogeny; northwestern pacific; phylogeography; pleistocene isolation; population-growth; striped mullet; teleostei mugilidae  
  Résumé Mugil cephalus sensu lato is a globally distributed complex of cryptic species whose distribution range and evolutionary history remains largely unknown. In the North West (NW) Pacific three species have been identified genetically among fish described morphologically as M. cephalus. Their distribution ranges are largely parapatric and has been proposed to mirror different thermal preferences. To date, few samples have been analyzed from South China Sea, which limits inferences on the evolutionary history of the species complex. We sampled fish identified morphologically as M. cephalus along Vietnamese shores and characterized them using the sequence polymorphism of two mitochondrial genes, the cytochrome oxidase I and cytochrome b. This demonstrated that all three species described in the NW Pacific are present in both northern and southern Vietnamese waters. Although the difference in species abundance reflects those observed in the NW Pacific, no phylogeographic pattern was revealed. In addition, no population structure was observed whatever the species or the distribution range considered, which indicates a significant level of gene flow that maintains genetic homogeneity of the three species. It is also conceivable that each species experienced a recent population expansion from a single ancestral population. Finally we suggest that if the cold waters of the NW Pacific present a physiologic challenge leading to the almost parapatric distribution of the three species, then it is likely that the warm surface temperatures of the South China Sea negate this barrier.  
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  ISSN 2470-1394 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2160  
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Auteur Toussaint, A.; Charpin, N.; Beauchard, O.; Grenouillet, G.; Oberdorff, T.; Tedesco, P.A.; Brosse, S.; Villeger, S. doi  openurl
  Titre (up) Non-native species led to marked shifts in functional diversity of the world freshwater fish faunas Type Article scientifique
  Année 2018 Publication Revue Abrégée Ecol. Lett.  
  Volume 21 Numéro 11 Pages 1649-1659  
  Mots-Clés assemblages; biodiversity; Biotic exchanges; communities; extinction; extirpations; functional richness; functional divergence; homogenization; hydropower; introduction; invasion; islands; macroecology; patterns; richness  
  Résumé Global spread of non-native species profoundly changed the world biodiversity patterns, but how it translates into functional changes remains unanswered at the world scale. We here show that while in two centuries the number of fish species per river increased on average by 15% in 1569 basins worldwide, the diversity of their functional attributes (i.e. functional richness) increased on average by 150%. The inflation of functional richness was paired with changes in the functional structure of assemblages, with shifts of species position toward the border of the functional space of assemblages (i.e. increased functional divergence). Non-native species moreover caused shifts in functional identity toward higher body sized and less elongated species for most of assemblages throughout the world. Although varying between rivers and biogeographic realms, such changes in the different facets of functional diversity might still increase in the future through increasing species invasion and may further modify ecosystem functioning.  
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  ISSN 1461-023x ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2425  
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