Project description:Flower phenotypes in the species Diplacus aurantiacus in Southern California along an east west transect range from large, yellow, insect-pollinated flowers through orange flowers to small, red, bird-pollinated flowers. Until now, intermediate forms were attributed to recurrent hybridization at the (sub)-species level. However, by monitoring the flower phenotypes of these populations in field studies over the past 20 years, Rolf Baumberger observed that the transition in flower phenotype occurs during the lifespan of individual long-lived plants, thus ruling out a hybrid origin of intermediate forms. Further research has revealed that this transition bears the hallmark of an epigenetic transition. The small, red, bird-pollinated state is stable and heritable but reverts at frequencies of 1-2 %, much higher than that of genetic alterations. In our first approach a comparative transcriptome analysis of individuals of both stable morphotypes, we like to unravel candidate genes involved in floral colour and morphology determination.