Search results for "POPULATIONS"

Evolution of parasitism.

2019

Emotions et personnalité : au cœur des décisions chez un poisson monogame

2018

During their lives animals constantly need to make decisions that influence their survival and their reproductive success. The objective of this thesis was to evaluate the role of two variability sources in decision-making — personality and emotional states — in a sexual context in a monogamous fish, the convict cichlid. Our work about personality highlights its importance on pair compatibility and reproductive success. We also observe that reactive individuals adjusted their behaviour to their partner and thus increased their reproductive fitness. This result supports the hypothesis that reactive individuals are more flexible and thus compensate for their weak competitiveness.Personality t…

Eight microsatellite markers isolated from common ragweed (Ambrosia artemisiifolia L.) and cross-amplification with herbarium specimens

2009

 ; Eight microsatellite markers were developed for population genetic analyses of the common ragweed, Ambrosia artemisiifolia. Markers were tested for amplification with three populations (two recent populations from France and North America, and one historical population from herbarium specimens). These loci revealed a high level of genetic variability (5-19 alleles per locus; expected heterozygosity, 0.48-0.92). No significant deviation from Hardy-Weinberg equilibrium and no linkage disequilibrium were observed. The data thus demonstrate their utility as efficient genetic markers for determining the genetic diversity, population differentiation, and gene flow among invasive, native, and h…

Molecular evolution within and between populations of Arabidopsis thaliana: the FRIGIDA gene

2003

Possible role of eclampsia/preeclampsia in evolution of human reproduction.

2008

10 pages

Spider webs designed for rare but lifesaving catches

2005

International audience

Identification of Traits Implicated in the Rhizosphere Competence of Fluorescent Pseudomonads: Description of a Strategy Based on Population and Mode…

2009

E-book; International audience; The lack of consistency of the beneficial effects of inoculated fluorescent pseudomonads has often been related to their bad survival in the rhizosphere. In this review, we describe the strategy followed over the last decade to study traits involved in the rhizosphere competence of these bacteria. The diversity of indigenous populations associated with plant roots was first compared to that of populations associated with uncultivated soils in order to identify traits that discriminate these populations. The involvement of these bacterial traits in the rhizosphere competence was then assessed by comparing the competitiveness of a wild-type strain to that of mu…

Fragmentation des habitats et interactions hôtes-parasites

2021

Habitat fragmentation is one of the main threats to global biodiversity and despite an abundant literature on the impact of fragmentation on species abundance and diversity, the consequences of this global change in terms of ecological and evolutionary processes remain poorly understood. Beyond their direct contribution to biodiversity, as species-rich category of organisms, parasites could be involved in biodiversity change as key actors of ecological and evolutionary processes. The present work aims to understand the effect of forest fragmentation on host-parasite interactions. It is based on a large sampling carried out in the Lesser Antilles and in French Guiana, and allowing the obtent…

Adaptation à l'environnement : métabolisme et communication bactérienne

2010

Analyse des réseaux trophiques et quantification des interactions

2017

Prod 2017-344e SPE équipe EA GESTAD INRA; National audience; L’importante littérature consacrée au sujet suggère une relation positive entre la biodiversité en milieu agricole et la fourniture de services écosystémiques, notamment le service de contrôle des ravageurs par leurs ennemis naturels. Cependant, cette relation n’est que statistique et de nombreux contre-exemples peuvent être trouvés. L’une des raisons principales de l’absence d’additivité des effets des ennemis naturels réside dans la complexité des réseaux d’interactions qui se mettent en place dans les communautés diversifiées. Ainsi, par exemple, des phénomènes de compétition, voire de prédation intra-guilde peuvent conduire à …