One out of every three species of insects is a plant-eating insect, but most plant-eating insect species feed on only a few plant species. Although this phenomenon is clearly relevant for basic and applied biology, it is currently not well understood. This project addresses this issue by exploring patterns of biological diversity in the sap-sucking bug species of North America. Specifically, it tests the idea that both the high species diversity and the narrow diets of plant-eating insects are the result of co-evolutionary interactions with plants. These interactions are analogous to an arms race; plants evolve diverse defenses against plant-eating insects, which, in turn, evolve diverse (and specific) ways of overcoming those defenses. This idea has been central to explanations of plant-eating insect diversity for more than half a century. But until recently, researchers have lacked the resources to test it. This project will pull together those resources, and give us an unprecedented opportunity to advance our understanding of the forces that generate biological diversity. This project will provide education and training opportunities for biology students and instructors at multiple career levels, and from multiple backgrounds. The goal is to train biodiversity scientists, and to improve access to biodiversity science for underrepresented groups.
This project aims to identify ecological factors that drive host-use evolution and speciation in plant-eating insects. It uses Nearctic aphids as a model system and has three objectives: 1) Use DNA sequence data to estimate phylogenetic relationships among ~500 aphid species. 2) Use more than a quarter of a million specimen records and the primary research literature to characterize the niche of each Nearctic aphid species. 3) Use comparative statistical analyses to test hypotheses about the evolution of aphid species and niches. Corollary objectives are to improve aphid systematics and gain insights into the general evolutionary processes that beget biodiversity. This research may enable researchers to gain insights into economically important aspects of aphid biology, such as disease vector capacity and invasiveness. In turn, these may lead to better strategies for excluding and controlling aphid populations, which could increase the efficiency and sustainability of U.S. agriculture.
