Abstract
The origin of new species coincides with changes in mating preferences (prezygotic isolation) and/or with incompatibilities between genotypes that cause hybrid inviability (postzygotic isolation). All speciation models have in common that they concentrate on especially chosen simplified genetic scenarios, which imply that speciation usually follows sooner or later whenever a population becomes genetically very polymorphic. However, in nature, discrete polymorphisms are also very common that do not seem to lead to new species. The simplified genetics in speciation models are often geared towards obtaining new species, which makes them useless to analyse the likelihood that an existing polymorphism will speciate. We will make a start with assessing the dependence of the odds for speciation on genetic and ecological degrees of freedom or dimensions. The goal of this project is twofold: (1) Investigate the robustness of conclusions from existing speciation models by varying genetic and ecological dimensions. (2) Apply the theory developed under (1) to analyse a field system that is often polymorphic, but that not does always speciate, to wit polymorphisms and speciation of different mimetic forms in butterflies.
Netherlands