*Postdoctoral position at ISEM Montpellier France* *Can assisted gene flow rescue an endangered plant from extinction in a changing climate?* *Starting date: *September 2024-(no later than December 2024) *Duration:*24 months *Location: *Institut des Sciences de l'Evolution, Montpellier, France *Net income :*from 2300 to 3300 euros per month depending on experience. Benefits include pension and health insurance *Overview:*The postdoctoral researcher will analyze several data sets on phenotypic and genomic variation in the endemic endangered plant /Centaurea corymbosa/, with the general aim of assessing if assisted gene flow has the potential to halt the decline of the species. Estimates from the statistical analysis will be used to parametrize models of evolutionary rescue for that species. This post-doctoral project of 24 months is part of the project FloRes - Gene Flow to the Rescue: Assessing the need, effectiveness, risks and ethical implications of manipulating gene flow to improve adaptation to climate change for long-lived plants (ANR 2022-2026). The selected candidate will be based at the Institut des Sciences de l'Evolution (ISEM), Montpellier, France. They will be supervised by Ophélie Ronce, Eric Imbert, François Rousset and Agnès Mignot with interactions with other collaborators from the FloRes project. *Keywords*: quantitative genetics, conservation genomics, evolutionary rescue, statistical analysis, adaptive potential, heterosis, outbreeding depression, gene flow, life history traits, population dynamics, fitness, structured populations, population reinforcements, translocations. *Context:*Climate change may become a major driver of species extinction in the near future. Recurrent episodes of drought and high temperatures in particular accelerate the decline of the highly endemic plant /Centaurea corymbosa/, an endangered perennial plant whose entire fragmented range is limited to 3km2 on a small massif near Narbonne. The population dynamics of the species has been surveyed by our team for more than 30 years, which allows parametrizing demographic models that predict a high probability of extinction for most of the 6 extant populations in the next two decades. Demographic and genetic surveys have shown that gene flow is very rare between these 6 populations.Given the critical situation of the species, managers have undertaken a reinforcement of all 6 extant populations in 2018, 2019 and 2021, planting about 40 000 seeds, obtained from free crosses between all populations in a common garden. /Our aim is to test whether such admixture between multiple genetic sources could improve the populations survival and capacity to adapt to climate change/. To answer this question, we have: (i) developed and parameterized eco-evolutionary models for the species predicting how much genetic variation for critical adaptive traits must be increased within each population for adaptive evolution to rescue the populations from rapid extinction, (ii) set up a quantitative genetic experiment with seeds from the same progenies as used for the reinforcements to estimate the amount of genetic variation for life history and functional traits in the reinforcements in a common garden, (iii) performed controlled crosses between the different populations and measured the fitness of F1 and F2 progeny in controlled conditions, (iv) measured the complete life history in the field of individuals that have been introduced in the natural populations. Genotyping, using NGS, of leaf samples from individuals in the common garden and in the wild is under way. *Objectives:*We expect data sets, including genotyping, to be nearly completed at the beginning of the contract and the contribution of the postdoctoral researcher to data acquisition to be marginal, their contribution being focused on data analysis (including bioinformatics analyses) and statistical modelling and inferences. The postdoctoral researcher will use the genotyping and phenotypic data sets to 1) estimate genetic relatedness between individuals and identify the population of origin of each parental line in the reinforcements, 2) test if offspring from crosses between different populations have a higher fitness under stressful conditions, 3) test if mixing sources in the reinforcement increases heritable variation for adaptive traits. These estimates of hybrid vigor and genetic variation for different life history traits will be used to predict the demographic consequences of assisted gene flow with the eco-evolutionary models developed by other collaborators in the project. To put these results in context, genomic data could also be used to infer the recent demographic history of the 6 extant populations of /C. corymbosa/. *Working environment*: The postdoctoral research will join the Evolution&Demography team at ISEM, led by Ophélie Ronce (https://isem-evolution.fr/en/equipe/evolution-and-demography-team/). They will interact in particular with Eric Imbert and Agnès Mignot who supervised different experiments in the field and controlled conditions on /C. corymbosa/, François Rousset for statistical advice for the analysis of life history traits variation, Julien Ofresson who is developing evolutionary rescue models for the species, David Carbonell, Marie Challe, Denis Orcel and Armelle Kempf who are in charge of data acquisition, and Ophélie Ronce who coordinates the FloRes project. Other collaborators at ISEM outside the team include: Elodie Flaven for her expertise in the genotyping of /C. corymbosa/ and bioinformatics analysis, Pierre-Alexandre Gagnaire who is involved in the development of demographic inference from haplotagging sequencing in /C. corymbosa/. *Candidate profile: * -PhD in evolutionary biology, with a solid academic background in quantitative genetics. -Strong background in statistical analysis of life history traits, evolutionary genomics and bioinformatics -Clear communication in English in both spoken and written form. -Good interpersonal skills needed for teamwork *How to apply:* You can contact ophelie.ronce@umontpellier.fr for inquiry. Applications must go through https://emploi.cnrs.fr/Offres/CDD/UMR5554-OPHRON-006/Default.aspx?lang=EN The application must include a cover letter explaining your interest and ability to carry out the project, a complete CV, and a maximum of 5 publications most relevant to the project attached to the CV, and the names and contacts (email and phone number) of two academics capable of assessing your competence for the position Ophélie Ronce (to subscribe/unsubscribe the EvolDir send mail to golding@mcmaster.ca)