Collaborative Proposal: Dimensions: The evolution of novel interactions within a network of plant, insect and microbial biodiversity

University Of Tennessee Knoxville, Knoxville TN

Investigators

Abstract

All species on earth interact with other species in complicated networks that include plants, animals, and microbes. These interaction networks have long fascinated biologists, who are interested in why some species depend on each other and in how these relationships matter for maintenance of biodiversity. For example, why do most insects that eat plants consume only a few types of plants in any one location? And, how did it happen that many of these insects depend on beneficial microbes (fungi and bacteria) that are found nowhere else except with those insects. This project will explore how such specialized interactions arise. Specifically, researchers will investigate the evolution of new interactions among insects, microbes, and an economically important plant (alfalfa) in western North America. By identifying the key factors that underlie the insect-microbe-plant interactions in this study system, the research will fill a substantial gap in our understanding of the diversity of life, and enhance our ability to predict how global change will affect biological diversity and ecosystem function. The researchers will also engage and collaborate with the public through a discovery-based citizen science program, and will develop new analytical tools to benefit other scientists who are interested in how species come to depend on each another. This project examines a complex network of interacting biodiversity, including macroscopic and microscopic organisms, to answer a fundamental question: What role does biodiversity play in the evolution and maintenance of novel interactions? The research team takes advantage of a well-studied plant-insect-microbe system to investigate the importance of multiple layers of inter- and intra-specific diversity for predicting the evolution of novel interactions, specifically the colonization of alfalfa by the Melissa blue butterfly and microbes. The project combines a systems approach to biological complexity with manipulations that allow the researchers to integrate three focal dimensions of biodiversity: (1) functional diversity, encompassing how variation in phytochemistry, larval performance, and butterfly egg-laying preference are shaped by microbial, fungal, plant and caterpillar interactions; (2) genetic diversity, including the role of genomic variation within and among populations of interacting plants and insects, both in the wild and in an experiment context; and (3) phylogenetic diversity, focusing on gut bacteria in insects, as well as fungal and bacterial endophytes in plants.