OOS 18-5 - Distinctive roles of timing-based trait variation in plant-herbivore interactions

Plant traits can change dramatically over time, as plants develop from spring to fall and from seedling to maturity. Likewise, plant developmental timing can vary dramatically within and among populations. However, compared with genetic and environmental variation, little is known about how timing variation contributes to intraspecific trait variation and community dynamics. In the work reported here, I aimed to test how timing variation translates to trait and community variation in the context of plant-herbivore interactions. Timing variation was manipulated either directly (by varying planting dates) or by altering temperature cues. I found that among-plant variation in developmental timing impacted herbivory rates, plant neighbor effects, and arthropod community richness. Timing-based variation has different causes and consequences than other types of trait variation, and so should be considered directly in studies of trait-mediated interactions. Doing so will help clarify the overall role of intraspecific trait variation in ecological communities.