In the last decades, we have observed at a global scale a resurgence of problems related to the colonization of alien invasive species, largely due to human activities (development of international trade and intercontinental transportation). Invasive species are generally considered as having a negative effect on both the economy (crop damage and health problems) and the environment (loss of biodiversity). Managing and controlling invasive species requires an understanding of the ecological and evolutionary processes that underlie invasions, even more so now that we need to reduce pesticide use. On a more academic side, biological invasions represent “natural experiments” for evolutionary biologists who study the genetic bases of adaptation.
In this project, we will investigate the evolutionary processes at play during a biological invasion with a particular focus on the mechanisms and consequences of adaptation. We will also infer the evolutionary potential in this species, so as to make short-term and longer-term predictions with respect to adaptation.
This project will carried on an Asian drosophila species (Diptera: Drosophilidae) that has recently invaded both Europe and North America: Drosophila suzukii or spotted wing Drosophila. Unlike most Drosophilids D. suzukii uses a sclerotized ovipositor to lay eggs in unripe fruits causing dramatic losses to the fruit industry, with a yearly cost estimate exceeding one billion euros worldwide. The rapid dissemination of D. suzukii in North America and Europe demonstrates its remarkable ability to adapt or acclimate to new environments.
In this project, we propose to: (1) precisely describe and quantify phenotypic variation within and between populations, using quantitative genetics and reaction norm analyses; (2) characterize precisely the routes of invasion at a worldwide scale, and characterize the molecular variation associated with the invasion success, using genomics and transcriptomics approaches; (3) analyze the functions of the candidate genes and genomic regions so-identified, characterize the relative importance of natural selection and genetic drift in shaping phenotypic differentiation between native and invasive populations, and analyze the role of transposable elements in adaptation; (4) investigate how phenotypic plasticity, micro-evolution and symbionts contribute to the capacity of D. suzukii to feed on many different crop species (and therefore switch hosts) within a year, a key step towards predicting infestations in real-time and deploying sustainable control measures.
The strength of this project lies in several points: i) the complementarity of the approaches (molecular and phenotypic), ii) the skills of the partners on both the methods/technics (including the development of new inferential methods of general interest for the statistical analysis of populational pangenomics data) as well as the concepts that will be used, iii) the good knowledge of the biological model that has been the subject of several publications by the partner labs, iv) our collection of population samples from all around the world that has allowed to obtain valuable and original results on the routes of invasion of this species, v) an existing collaborative network with various socio-economic partners that will help will field tasks and allow a rapid and efficient transfer of knowledge.
Madame Patricia GIBERT (Laboratoire Biométrie et Biologie Evolutive)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
LBBE - CNRS Laboratoire Biométrie et Biologie Evolutive
MNHN - ISyEB Institut de Systématique, Evolution, Biodiversité
CBGP Centre de Biologie pour la Gestion des Populations
Help of the ANR 566,159 euros
Beginning and duration of the scientific project: September 2016 - 48 Months