The goal of my PhD is to study South American mammals’ evolutionnary history throughout the last 66 Million years and to determine the likely drivers of its changes. To this end, I combine data from the fossil record and from phyogenies of living species to make diversification inferences in environment-dependent models. I am also interested in the bias in palaeobiogeographical frameworks, and more generally, in bridging the gap between the past and the present to understand the dynamics of biodiversity.