I am studying the process of diversification in birds using phylogenetic and macroevolutionary approaches. Specifically, I am investigating how fundamental mechanisms such as speciation, extinction, phenotypic evolution, and dispersal interplay and influence diversification. I analyze molecular, phenotypic, and ecological data using phylogenetic and comparative methods to reveal the tempo and mode of bird evolution. My work is highly integrative and aims for the unification of evolutionary and ecological theories of biodiversity.