From contradiction to prediction: When is hybridization helpful or harmful to invaders?
A major aim in evolutionary biology is to understand the repeatability of adaptation and the role of hybridization during invasion. The thesis used two alien plant species, Cakile edentula and C. maritima, to investigate phenotypic and genotypic signals of adaptation and the contribution of hybridization on two continents. Parallel latitudinal clines in phenology and size evolved in the alien ranges in only 100-150 generations, mirroring the native ranges in both species. Moreover, I found hybridization occurred in both invaded ranges and evidence that introgression of the same regions has aided rapid parallel climate adaptation in two separate invasions of C. maritima.