My research is centered around broad conceptual and basic influences of interspecific interactions on ecological and evolutionary patterns (structure) and processes (mechanistic dynamics) within and across levels of biological organization, ranging from organisms, populations and communities to ecosystems, landscapes and biomes. My studies entail both basic research and applied global environmental biology. While I am broadly interested in interspecific interactions in general, my studies are especially aimed at advancing our knowledge of mutualism, which lags behind predation and competition as a third pillar in the study of species interactions — largely due to a deficiency in mechanistic theory that can transcend study systems and guide empiricism. Using multiple synergistic approaches to research, I strive to improve our knowledge of nature by integrating theory and empiricism through experimental field studies, theoretical models, and modern computational techniques for model fitting, parameterization, and model selection. My empirical work is currently focused on plant-animal interactions in the Sonoran Desert of Mexico, including the coevolved pollinating seed-consuming mutualism between senita cacti and senita moths; defense mutualisms between plants and ants; the senita food web module; and mutualistic plant-ant networks at local and broad geographic scales. I welcome students and collaborators with interests in concepts and study systems of my research, as well as those with other ideas, study systems, and interdisciplinary topics.