Disentangling adaptive and non-adaptive drivers of complex trait diversification

One urgent challenge, not the least at a time of rapid environmental change, is to understand how evolution proceeds across species ranges, especially in relation to interactions with other species, as communities of interacting species are reshuffled worldwide.

This proposal leverages insights from more than a decade of studies of the interactions between Lithophragma plants and their specialized and generalized pollinators revealing tremendous inter- and intraspecific variation in ploidy-level, floral scent, size, and morphology.

Our longstanding hypothesis was that the floral trait diversity is generated by a combination of the genomic underpinnings of trait variation and locally divergent coevolution between Lithophragma and their highly specialized Greya moth pollinators.

However, our recent work indicates that polyploidization affects some, but not all, functionally relevant aspects of the floral phenotype, and that Greya moths are the major pollinators only in some populations.

These discoveries combined with our extensive phenotypic and genetic resources compiled over the latest decade enable us to address to what extent floral phenotypes and their genomic basis change in a rapid and repeatable fashion under divergent selection regimes. In the project, we combine greenhouse and field experiments, novel joint modelling techniques and genomic analyses.

Thereby, we address a core problem in evolutionary biology – to link population diversification to local evolution.