Search results for "Phylogénie"
showing 10 items of 11 documents
Macroecological properties of ammonites : spatial distribution, phylogeny, and faunal similarity
2016
The present work, which lies between macroecology and macroevolution, focuses on the spatio-temporal dynamics of early Pliensbachian ammonites of the western Tethys. Two main questions are addressed: how does inter-assemblage compositional similarity decrease with geographical distance? What is the relationship between species range size and phylogeny, species duration and latitudinal position?Ammonite dispersal dynamics are studied through a multi-scale Similarity Distance Decay analysis. We show that their long-distance dispersal is facilitated when the environment is more homogeneous and that it is not related to their morphology. This suggests that their long-distance dispersal occurred…
Les Ammonoïdes (Mollusca, Cephalopoda) : avancées et contributions récentes à la paléobiologie évolutive.
2009
12 pages; Les ammonoïdes qui perdurent 335 Ma constituent un modèle de choix dans l'analyse du fait évolutif. Cet article de synthèse se propose d'aborder (1) : leur place phylogénétique au sein des céphalopodes et le choix d'un modèle actuel de référence ; (2) : la construction d'espaces phénotypiques qui offrent un angle d'étude pertinent de l'évolution biologique ; (3) : les concordances et discordances entre reconstruction phylogénétique et registre fossile et (4) : les reconquêtes postcrises, modèles d'étude de l'évolution à grande échelle. Il ressort que les ammonoïdes peuvent servir d'appui à de nombreuses thématiques paléontologiques (dynamique de la biodiversité, analyse phylogénét…
Effect of inoculation with selected Bradyrhizobium spp. on the survival and growth of Acacia mangium saplings after 20 months in the field
1999
This work was designed to test the long-term effect of the inoculation of #Acacia mangium# seedlings with 10 selected strains of #Bradyrhizobium spp.#. The percentage of survival of seedlings inoculated with any of the #Bradyrhizobium# strains was increased by 10% as compared to the control plants. However, out of the 10 #Bradyrhizobium# strains tested, only 3 strains, Aust l3c, Lu 4 and Tel 8, belonging to the phylogenelic group 1, significandy enhanced the growth of #A. mangium# after 20 months in the field. For the first time, inoculation with indigenous Malaysian strains #Bradyrhizobium# such as Tel 8 and Lu 4 at the seedling stage is reported to produce enhanced and sustained growth an…
La conscience animale
2016
La phylogénie des cercopithecinés encore en costruction.
2013
Les cercopithecines (guenons et autres taxa corrélées) sont un groupe de singes africains qui se composent d'environ 36 réelles espèces avec une évolution et une phylogénie três difficile à reconstruire. L’approche scolaire a la tendance à proposer la clusterisation du groupe en question en deux: strictement arboricoles et terrestres. Avec la présente, nous analysons de façon critique les différentes reconstructions phylogénétiques proposées aujourd’hui tout en conduisant une analyse sur la base des aspects moléculaires, chromosomiques et écologiques des espèces incluses dans le "groupe d'espèces" actuellement reconnu. Cette approche multidisciplinaire inclue la morphologie, l'écologie régi…
The gypsy database (GyDB) of mobile genetic elements: release 2.0
2011
This article introduces the second release of the Gypsy Database of Mobile Genetic Elements (GyDB 2.0): a research project devoted to the evolutionary dynamics of viruses and transposable elements based on their phylogenetic classification (per lineage and protein domain). The Gypsy Database (GyDB) is a long-term project that is continuously progressing, and that owing to the high molecular diversity of mobile elements requires to be completed in several stages. GyDB 2.0 has been powered with a wiki to allow other researchers participate in the project. The current database stage and scope are long terminal repeats (LTR) retroelements and relatives. GyDB 2.0 is an update based on the analys…
Tempo and mode of early gene loss in endosymbiotic bacteria from insects
2006
Abstract Background Understanding evolutionary processes that drive genome reduction requires determining the tempo (rate) and the mode (size and types of deletions) of gene losses. In this study, we analysed five endosymbiotic genome sequences of the gamma-proteobacteria (three different Buchnera aphidicola strains, Wigglesworthia glossinidia, Blochmannia floridanus) to test if gene loss could be driven by the selective importance of genes. We used a parsimony method to reconstruct a minimal ancestral genome of insect endosymbionts and quantified gene loss along the branches of the phylogenetic tree. To evaluate the selective or functional importance of genes, we used a parameter that meas…
Phylogénie et paléographie des truffes
2008
National audience
A paleontological viewpoint on the "6th mass exinction".
2020
Temperature and pH define the realised niche space of arbuscular mycorrhizal fungi
2021
Made available in DSpace on 2021-06-25T11:52:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-04 European Regional Development Fund (Centre of Excellence EcolChange) University of Tartu (Estonian Research Council ) Moscow State University Natural Sciences and Engineering Research Council of Canada Discovery Grant Russian Science Foundation Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Swedish Research Council (Vetenskapsradet) The arbuscular mycorrhizal (AM) fungi are a globally distributed group of soil organisms that play critical roles in ecosystem function. However, the ecological niches of individual AM fungal taxa are poorly understood. We collected > 300 s…