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Dispersal and vicariant hypotheses have for decades been at odds with each other, notwithstanding the fact that both are well‐established natural processes with important histories in biogeographic analyses. Despite their importance, neither dispersal nor vicariant methodologies are problem‐free. The now widely used molecular techniques for generating phylogenies have provided a mechanism by which both dispersal‐ and vicariance‐driven speciation can be better tested via the application of molecular clocks; unfortunately, substantial problems can also exist in the employment of those clocks. To begin to assess the relative roles of dispersal and vicariance in the establishment of avifaunas, especially intercontinental avifaunas, I applied a test for clocklike behavior in molecular data, as well as a program that infers ancestral areas and dispersal events, to a phylogeny of a speciose, cosmopolitan avian genus …