Climate change and interaction diversity

Most climate change scenarios predict that biodiversity will decrease and insect outbreaks will increase in frequency and intensity as a result of increases in CO₂, mean global temperatures, and extreme weather events. Over the past decade, hundreds of empirical studies and modeling approaches have addressed hypotheses focused on effects of climate change parameters on a broad diversity of insect trophic interactions, since direct effects of these parameters on insects can be enhanced or countered by indirect effects, such as trophic cascades. One component of biodiversity and insect trophic interactions that has not been carefully examined is interaction diversity. I define trophic interaction diversity as the number of trophic interaction links per unit area - this variable is tightly linked to ecosystem services and is a better predictor of important ecosystem parameters, such as stability and function. Trophic interaction diversity is most likely declining more quickly than species richness or other measures of biodiversity, We have used models and empirical data to examine how perturbations, from small scale disruptions to global change, affect interaction diversity. Based on our models, experiments, and decades of our tritrophic rearing data across the Americas, it is clear that climate change will continue to erode trophic interaction diversity and one of the main mechanisms is through phenological asynchrony.