The ability of plants to disperse over long distances can influence evolutionary processes. Willis et al. examine the tribe Brassiceae (Brassicaceae) and find that increased dispersal ability has evolved in multiple ways through different combinations of fruit traits, and it is associated with both increased geographic range size and higher diversification rates. They conclude that evolution of increased dispersal ability can influence macro-evolutionary processes, possibly by increasing the propensity for long-distance dispersal. In particular, it may increase speciation and consequent diversification rates by increasing the likelihood of geographic and thereby reproductive isolation.