Evolution to the rescue? Understanding the evolution of plant behaviour in response to rapid environmental change.

Understanding phenotypic plasticity is essential to predict how organisms and communities will respond to rapid environmental change. Fitness could be maintained through differential gene expression or increases of beneficial alleles in the population, establishing new plasticity for novel environmental regimes ("evolutionary rescue"). Field experiments conducted on ragwort species Senecio chrysanthemifolius (Asteraceae), reveal "Adaptive Potential" (AP) genotypes, that show higher fitness than the average at elevations above their native range. However, transplant experiments cannot increase temperature before encountering sea level. I will, therefore, cultivate cuttings in laboratory growth chambers to test the effects of increased temperature on phenotypic plasticity and its genomic basis. Detailed phenotypic trait analysis and RNA-seq will identify differentially expressed genes and determine which genotypes show higher relative fitness as temperatures increase. Study of molecular pathways and gene expression will increase our understanding of the potential and limits to plasticity. Quantifying changes in functional traits (phenotypic plasticity), and their relative fitness will indicate which genotypes, demonstrate the potential for evolutionary rescue. Similarly, studies of the patterns of gene expression underlying these phenotypes will explore which genomic regions, and which kinds of gene network are associated with such novel forms of phenotypic plasticity.