Integrating genetics and geography in population dynamics

The evolution of a population depends on the way its individuals interact with one another and with the environment. In spatially distributed populations interactions are local and specific features of the geography can affect its genetic evolution. In this talk I will first discuss an individual based model of speciation that is driven by local mating and does not require the existence of geographic barriers separating the population in isolated groups. Each individual will be characterized by its position in space and by a genome composed of several biallelic genes. In the model mating is possible only if the individuals are sufficiently close to each other in space (local mating) and also similar genetically (assortative mating). Depending on the parameters of the model the population can evolve into separate species even in the absence of natural selection. Using the same theoretical framework I will show simulations for ring species, where an initially localized population expands in two directions around a physical barrier in such a way that the two expanding fronts meet at the other side of the barrier after many generations. Finally I will discuss coevolution in a spatially distributed population of predators and prey that engage into an arms race. In all cases the results of simulations will be compared with empirical data.