Data from: Insect herbivores drive real-time ecological and evolutionary change in plant populations

Insect herbivores are hypothesized to be major factors affecting the
ecology and evolution of plants. We tested this prediction by suppressing
insects in replicated field populations of a native plant, Oenothera
biennis, which reduced seed predation, altered interspecific competitive
dynamics, and resulted in rapid evolutionary divergence. Comparative
genotyping and phenotyping of nearly 12,000 O. biennis individuals
revealed that in plots protected from insects, resistance to herbivores
declined through time due to changes in flowering time and lower defensive
ellagitannins in fruits, whereas plant competitive ability increased. This
independent real-time evolution of plant resistance and competitive
ability in the field resulted from the relaxation of direct selective
effects of insects on plant defense and through indirect effects due to
reduced herbivory on plant competitors.