Sensitivity of Self-Organized Speciation to Long- Distance Dispersal

Previous work has shown that speciation can result from the self-organized accumulation of multiple mildly underdominant (nearly neutral) loci in a continuous population, when mating is spatially localized. In contrast, when mating is panmictic, underdominance is quickly eliminated and the population always converges on a single genotype, as predicted by mean-field approximations. The focus of this work is to examine the sensitivity of selforganizing speciation to the assumption of purely localized interactions. We alter the interaction topology from nearest neighbor interactions to panmictic interactions in two ways: (i) by increasing the size of the contiguous mating neighborhoods and (ii) by allowing for long-distance dispersal of individuals with increasing probability. Our results show self-organized speciation to be robust to mating neighborhood sizes significantly larger than nearest neighbor interactions and to probabilities of long-distance dispersal that fall well into the range of so called “small-world” interaction topologies.