show Abstracthide AbstractThe project focused on naturally occurring populations of several Arabidopsis species with the main goal of understanding how whole-genome duplication modulates evolutionary trajectories. The first objective was to understand how species adapt to whole-genome duplication, as an event that leads to severe physiological constraints. The second objective was to understand whether whole-genome duplication also confers a systematic advantage, e.g. when polyploids accumulate more genetic variation due to polysomic masking, and whether this variation facilitates adaptation. The third objective was to understand the evolutionary history of the focal species A. arenosa, A. lyrata, A. halleri, A. croatica and A. cebennensis.