Validity of pioneer dominance in range expansions with long-range dispersal

The pioneers who seed distant satellite colonies can have a disproportionate impact on the evolution of species undergoing range expansions with long-range dispersal. Lattice-based models that focus on the pioneers find that population outcomes are closely tied to the "heaviness" of the tail of the dispersal distance distribution. We used continuous space, individual-based simulations to ascertain when it is valid to use such models. We find that they can capture the structure of range expansions in populations well outside their modeling assumptions, but they can miss important dynamics between coexisting or competing alleles when individuals share resources with many others. Our results highlight the predictive power of simple models of expanding populations and shine a light on where they fall short.