Herbivory is a driving force of plant evolution. Plants produce a wide variety of physical and phytochemical resistance traits to defend themselves against herbivores. These defenses exist in constitutive (produced in the absence of damage) and plastic (produced after damage) forms. In order to evolve, resistance traits must have underlying genetic variation. Here, I discuss the following questions: 1) What are genetic patterns of plant defense production in monkeyflower (Mimulus guttatus)? 2) What are the effects of genetic variation in plant defenses on higher trophic levels?
Results/Conclusions
Results show an overall lack of strong genetic correlations among traits, indicating that there are few genetic constraints on independent evolution of resistance traits. Particular resistance traits do not influence generalist and specialist herbivore performance in the same way, and plants respond plastically to generalist and specialist herbivores in different ways. These results indicating that selection pressures in natural M. guttatus populations are likely complex and dependent on herbivore community composition.