Latitudinal variation in pollination and herbivory

Project Overview
Project Abstract: 
Species interactions such as pollination and herbivory have often been observed to be more prevalent or intense at lower latitudes. This may explain why biodiversity is so high in the tropics. Coevolution in species interactions could cause high diversification rates compared to the main challenge in temperate environments, winter, which does not evolve. This study tests the hypotheses that, compared to plants at higher latitudes, lower-latitude plants experience higher herbivore pressure, are better defended against herbivores, rely more on pollinators, and invest more in pollinator attraction and reward. The study will compare indices of pollination and herbivory along a gradient from Michigan to Florida within Phytolacca americana (pokeweed). I will also collect seeds from pokeweed and additional wide-ranging plant species to study plant defense and mating systems in the greenhouse at Michigan State University.