Speciation processes in fungi examined through experimental and empirical approaches

Although more than 100.000 fungal species exist, fungi are largely missing in the speciation debate. Speciation theory is based mainly on research on animals and plants and little is known whether fungi conform to general models of speciation. Four differ ent boreal/nemoral wood-decay species complexes (Basidiomycota) will be used as model organisms in this project, selected because multiple breeding units (intersterility groups) exist within the species complexes, indicating ongoing or recent speciation. Preliminary data indicates that hybridization and/or introgression occurs in at least two of the species complexes. One main research topic is to reconstruct speciation mechanisms in fungi through biogeographical interpretation of phylogenies (phylogeogra phy) based on multilocus DNA datasets. The ecological component of the speciation process will be studied through various physiological experiments. Various fitness parameters and ecological characteristics will be investigated in the divergent allopatric /sympatric lineages and coupled to the phylogeographic information obtained. Various post-zygotic isolating mechanisms will be investigated, including chromosomal incongruence. In this way we also want to illuminate to what extent the frequently used pre- zygotic clamp connection formation criterion reflects reproductive isolation. Results from some studies indicate that reinforcement may be an important speciation mechanism in fungi. The importance of hybridization and reinforcement during fungal speciati on will be investigated through the analyses of hybrid zones and mating experiments between allopatric/sympatric populations. The team behind this project together shares the expertise and experience needed to carry through all of the proposed subprojects . We seek funding for one 100% post doc research position.