Spatially distributed population dynamics: speciation and coevolution

Abstract

We intend to study speciation and coevolution processes using theoretical and computational models. Speciation studies will be focused on mathematical models of spatially structured population genetics and on the application of computer models to the Cichlids fish from African lakes. This is a work already in progress where we seek to compare simulation results with empirical data. One of the important topics of the work is to understand the process of speciation reversal due to water turbidity causedby human action. Turbidity reduces the ability of fish to distinguish partners of the same speciesand promotes Interspecies matings. These matings produce fertile offspring (for the speciationprocess of cichlids is still incipient) generating hybrids that mix the species and reduce diversity. The studies on co-evolution studies will be based on two natural systems. The first one is inspired on the salamander snake populations that inhabits the west coast of United States, where the salamanders produce a poison that protects them from the snakes. These, on the other hand, develop resistance to the venom produced by the prey generating an {\ it arms races}. The evolution of poison and resistance is counterbalanced by their cost of production, leading to a balance. In the second system we study mutualistic and antagonistic interactions involving two species in spatially structured scenarios. Previous works have shown that the same pair of species can interact mutualistically or antagonistically depending on environmental conditions. In these cases, the genetic composition of populations will vary withlocation. When there is migration of individuals between different sites it creates a mosaic thatmay not reflect the type of local interaction. We intend to study the different mosaics that form asa function of the link topology between sites and details of local interactions. (AU)