Laboratory experiments under controlled chemostat conditions have indicated that evolution of algal populations can occur on ecological time-scales and can significantly alter community dynamics and ecosystem functioning. However, we do not know how important such evolutionary changes are in nature.
In a series of field-based experiments, we have manipulated the identity and degree of resource limitation. We are quantifying the relative amount of trait change in a community that results from changes in genomic variance within a population relative to changes in species abundance in a community in response to a changing environment. In particular, we are interested in whether the R* of species and populations within species determine their success and dominance in these semi-natural conditions. This will tell us how important adaptation is relative to changes in species abundance in ensuring future ecosystem functioning.