Plant diversification is driven by a complex interplay of geological, abiotic and biotic factors, and the relative contribution and potential synergistic or counteracting effects of these processes remain poorly understood. In this project, I will address these gaps by quantifying abiotic and biotic niche evolution and the importance of niche shifts and niche conservatism in the diversification of the Neotropical plant group Merianieae (Melastomataceae). I will combine macroevolutionary phylogeographic modelling with ecological niche modelling approaches and functional pollination biological experiments. A particular focus will lie on testing different hypotheses on the biomechanical functioning of buzz-pollinated flowers and their adaptive potential to variable abiotic and biotic conditions.