Sensitivity of Self-Organized Speciation to Long-Disctance 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.