My research focuses on the eco-evolutionary mechanisms that influence genetic diversity and its variations at the genome scale and in space. It spans micro- and macro-evolutionary timescales, starting with intra-population mechanisms and extending to the study of divergence leading to speciation, and finally to molecular evolution between isolated species. To study these different levels, I use concepts and analysis methods from population genetics and apply them to polymorphism data produced using genome sequencing technologies. My study models are mainly fish and marine invertebrates. Although essentially fundamental, my research has applications in aquaculture genetic programmes and in the conservation and management of natural populations.