Aidan Fielding: Simulations of trait evolution that exhibit evolutionary branching due to resource competition
Eco-evolutionary dynamics were strongly influenced by the combination of competition strength, dispersal level, and speed of environmental change. Dispersal introduced novel species combinations that altered fitness landscapes, while continuous environmental change introduced strong selection against the maintenance of coexisting competitors. As a consequence, diverse communities that also tracked environmental change were only maintained when strength of competition was strong, at intermediate levels of dispersal and environmental change. When competition was weaker, diverse communities were maintained by a spatial eco-evolutionary feedback loop, where populations from patches with distinct trait values colonized new patches, altered the strength of competition in that new patch, which in turn altered the strength of selection for resident species. These evolved residents then colonize other patches and alter their local distribution of competition strength, completing the feedback loop.
Our results thus indicate that understanding biodiversity loss in a changing world will require improved knowledge of both the constraint that competitive interactions place on adaptive potential as well as the opportunity that landscape connectivity can present for introducing novel eco-evolutionary dynamics.