EvoLunch Seminar: Meike Wittmann (University of Bielefeld, DE)
EvoLunch Seminar
The role of fluctuating selection and genetic dominance in the maintenance of polymorphism
"The role of fluctuating selection and genetic dominance in the maintenance of polymorphism"
Wednesday 14th May 2025
11:00 CET
Mondi 2a, Central Building, ISTA
Hybrid Meeting (for zoom link, email evolunch.seminar@ist.ac.at)
I will talk about a few projects where, together with various colleagues, I have explored the role of fluctuating selection and patterns of genetic dominance for the maintenance of polymorphism. In sum, these studies show that fluctuating selection can maintain genetic polymorphism, given the right dominance patterns. Nevertheless, on a genomic scale, fluctuating selection may rather be reducing than increasing levels of genetic diversity. Even without fluctuating selection, differences in dominance between the pleiotropic effects of an allele in different contexts can be a strong force for the maintenance of polymorphisms, as shown in an example model for the maintenance of chemodiversity in plants. Such dominance differences can arise easily, e.g. in metabolic pathways, and full dominance reversals are not required for the maintenance of variation. Using the example of a field study with Drosophila, I will also talk about the difficulty of disentangling different types of selection that could potentially maintain polymorphism.