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Auteur Jousset, A.; Eisenhauer, N.; Merker, M.; Mouquet, N.; Scheu, S. doi  openurl
  Titre High functional diversity stimulates diversification in experimental microbial communities Type Article scientifique
  Année 2016 Publication Revue Abrégée Sci. Adv.  
  Volume 2 Numéro 6 Pages (down) e1600124  
  Mots-Clés adaptive radiation; biodiversity; competition; evolution; phase variation; pseudomonas-fluorescens; recombination; root colonization; selection; soil  
  Résumé There is a growing awareness that biodiversity not only drives ecosystem services but also affects evolutionary dynamics. However, different theories predict contrasting outcomes on when do evolutionary processes occur within a context of competition. We tested whether functional diversity can explain diversification patterns. We tracked the survival and diversification of a focal bacterial species (Pseudomonas fluorescens) growing in bacterial communities of variable diversity and composition. We found that high functional diversity reduced the fitness of the focal species and, at the same time, fostered its diversification. This pattern was linked to resource competition: High diversity increased competition on a portion of the resources while leaving most underexploited. The evolved phenotypes of the focal species showed a better use of underexploited resources, albeit at a cost of lower overall growth rates. As a result, diversification alleviated the impact of competition on the fitness of the focal species. We conclude that biodiversity can stimulate evolutionary diversification, provided that sufficient alternative niches are available.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 2375-2548 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1649  
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Auteur Dalongeville, A.; Andrello, M.; Mouillot, D.; Lobreaux, S.; Fortin, M.-J.; Lasram, F.; Belmaker, J.; Rocklin, D.; Manel, S. doi  openurl
  Titre Geographic isolation and larval dispersal shape seascape genetic patterns differently according to spatial scale Type Article scientifique
  Année 2018 Publication Revue Abrégée Evol. Appl.  
  Volume 11 Numéro 8 Pages (down) 1437-1447  
  Mots-Clés caribbean reef fish; connectivity; divergent selection; ecological data; ecological genetics; landscape genetics; marine connectivity; marine fish; Mediterranean Sea; Mullus surmuletus; neighbor matrices; oceanography; population-structure; sea; seascape genetics; single nucleotide polymorphism; surmuletus  
  Résumé Genetic variation, as a basis of evolutionary change, allows species to adapt and persist in different climates and environments. Yet, a comprehensive assessment of the drivers of genetic variation at different spatial scales is still missing in marine ecosystems. Here, we investigated the influence of environment, geographic isolation, and larval dispersal on the variation in allele frequencies, using an extensive spatial sampling (47 locations) of the striped red mullet (Mullus surmuletus) in the Mediterranean Sea. Univariate multiple regressions were used to test the influence of environment (salinity and temperature), geographic isolation, and larval dispersal on single nucleotide polymorphism (SNP) allele frequencies. We used Moran's eigenvector maps (db-MEMs) and asymmetric eigenvector maps (AEMs) to decompose geographic and dispersal distances in predictors representing different spatial scales. We found that salinity and temperature had only a weak effect on the variation in allele frequencies. Our results revealed the predominance of geographic isolation to explain variation in allele frequencies at large spatial scale (>1,000km), while larval dispersal was the major predictor at smaller spatial scale (<1,000km). Our findings stress the importance of including spatial scales to understand the drivers of spatial genetic variation. We suggest that larval dispersal allows to maintain gene flows at small to intermediate scale, while at broad scale, genetic variation may be mostly shaped by adult mobility, demographic history, or multigenerational stepping-stone dispersal. These findings bring out important spatial scale considerations to account for in the design of a protected area network that would efficiently enhance protection and persistence capacity of marine species.  
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  Volume de collection Numéro de collection Edition  
  ISSN 1752-4571 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2422  
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Auteur Viblanc, V.A.; Saraux, C.; Murie, J.O.; Dobson, F.S. doi  openurl
  Titre Kin effects on energy allocation in group-living ground squirrels Type Article scientifique
  Année 2016 Publication Revue Abrégée J. Anim. Ecol.  
  Volume 85 Numéro 5 Pages (down) 1361-1369  
  Mots-Clés empirical-evidence; energy; history trade-offs; kin selection; lactating females; life-history; life-history trade-offs; litter size; maternal investment; matriline; philopatry; reproductive allocation; reproductive success; somatic allocation; spermophilus-columbianus; urocitellus-columbianus; yellow-bellied marmots  
  Résumé 1. The social environment has potent effects on individual phenotype and fitness in group-living species. 2. We asked whether the presence of kin might act on energy allocation, a central aspect of life-history variation. 3. Using a 22-year data set on reproductive and somatic allocations in Columbian ground squirrels (Urocitellus columbianus), we tested the effects of co-breeding and non-breeding kin on the fitness and energy allocation balance between reproduction and personal body condition of individual females. 4. Greater numbers of co-breeding kin had a positive effect on the number of offspring weaned, through the mechanism of altering energy allocation patterns. On average, females with higher numbers of co-breeding kin did not increase energy income but biased energy allocation towards reproduction. 5. Co-breeding female kin ground squirrels maintain close nest burrows, likely providing a social buffer against territorial invasions from non-kin ground squirrels. Lower aggressiveness, lower risks of infanticide from female kin and greater protection of territorial boundaries may allow individual females to derive net fitness benefits via their energy allocation strategies. 6. We demonstrated the importance of kin effects on a fundamental life-history trade-off.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0021-8790 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1699  
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Auteur Vandeputte, M.; Bugeon, J.; Bestin, A.; Desgranges, A.; Allamellou, J.-M.; Tyran, A.-S.; Allal, F.; Dupont-Nivet, M.; Haffray, P. doi  openurl
  Titre First Evidence of Realized Selection Response on Fillet Yield in Rainbow Trout Oncorhynchus mykiss, Using Sib Selection or Based on Correlated Ultrasound Measurements Type Article scientifique
  Année 2019 Publication Revue Abrégée Front. Genet.  
  Volume 10 Numéro Pages (down) 1225  
  Mots-Clés aquaculture; body shape; carcass; carp cyprinus-carpio; fillet yield; fish; genetic-parameters; heritability; production efficiency; production traits; quality traits; ratio; selection response; selective breeding; tilapia oreochromis-niloticus  
  Résumé Fillet yield, the proportion of edible fillet relative to body weight, is a major trait to improve in fish sold processed, as it has a direct impact on profitability and can simultaneously decrease the environmental impact of producing a given amount of fillet. However, it is difficult to improve by selective breeding, because it cannot be measured on live breeding candidates, its phenotypic variation is low, and, as a ratio, it is not normally distributed and a same change in fillet yield can be the result of different changes in fillet weight and body weight. Residual headless gutted carcass weight (rHGCW) is heritable and highly genetically correlated to Fillet% in rainbow trout, and can be predicted by the ratio of abdominal wall thickness to depth of the peritoneal cavity (E8/E23), measured on live fish by ultrasound tomography. We selected broodstock based on rHGCW, measured on sibs of the selection candidates, on ultrasound measurements (E8/E23) measured on the selection candidates, or a combination of both. Seven broodstock groups were selected: fish with 15% highest (rHGCW+) or lowest (rHGCW-) EBV for rHGCW, with 15% highest (E8/E23+) or lowest (E8/E23-) EBV for E8/E23, with both rHGCW+ and E8/E23+ (Both+) or rHGCW- and E8/E23- (Both-), or with close to zero EBVs for both traits (Mid). Seven corresponding groups of offspring were produced and reared communally. At harvest size (1.5 kg mean weight), 1,561 trout were slaughtered, measured for the traits of interest, and pedigreed with DNA fingerprinting. Offspring from groups Both+, rHGCW+ and E8/E23+ had a higher EBV for rHGCW than the control group, while down-selected groups had a lower EBV. Looking at the phenotypic mean for Fillet% (correlated response), up-selected fish had more fillet than down-selected fish. The highest difference was between Both+ (69.36%) and Both- (68.20%), a 1.16% units difference in fillet percentage. The change in Fillet% was explained by an opposite change in Viscera%, while Head% remained stable. Selection using sib information on rHGCW was on average more efficient than selection using the candidates' own E8/E23 phenotypes, and downward selection (decreasing Fillet%) was more efficient than upward selection.  
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  ISSN ISBN Médium  
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  Notes WOS:000505700800001 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2715  
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Auteur Boyd, C.; Grunbaum, D.; Hunt, G.L.; Punt, A.E.; Weimerskirch, H.; Bertrand, S. doi  openurl
  Titre Effectiveness of social information used by seabirds searching for unpredictable and ephemeral prey Type Article scientifique
  Année 2016 Publication Revue Abrégée Behav. Ecol.  
  Volume 27 Numéro 4 Pages (down) 1223-1234  
  Mots-Clés agent-based model; albatrosses; antarctic krill; central place foragers; colonies; evolution; foraging model; gannets; Habitat selection; insights; local enhancement; local enhancement; models; public information; search strategies  
  Résumé Understanding how seabirds and other central place foragers locate food resources represents a key step in predicting responses to changes in resource abundance and distribution. Where prey distributions are unpredictable and ephemeral, seabirds may gain up-to-date information by monitoring the direction of birds returning to the colony or by monitoring the foraging behavior of other birds through local enhancement. However, search strategies based on social information may require high population densities, raising concerns about the potential loss of information in declining populations. Our objectives were to explore the mechanisms that underpin effective search strategies based on social information under a range of population densities and different foraging conditions. Testing relevant hypotheses through field observation is challenging because of limitations in the ability to manipulate population densities and foraging conditions. We therefore developed a spatially explicit individual-based foraging model, informed by data on the movement and foraging patterns of seabirds foraging on pelagic prey, and used model simulations to investigate the mechanisms underpinning search strategies. Orientation of outbound headings in line with returning birds enables departing birds to avoid areas without prey even at relatively low population densities. The mechanisms underpinning local enhancement are more effective as population densities increase and may be facilitated by other mechanisms that concentrate individuals in profitable areas. For seabirds and other central place foragers foraging on unpredictable and ephemeral food resources, information is especially valuable when resources are spatially concentrated and may play an important role in mitigating poor foraging conditions.  
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  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1045-2249 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2068  
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