Ecology

I am an integrative microbial ecologist with training in microbial ecology, evolutionary biology, mycology, and genomics. I am an Assistant Professor of Ecosystem Genomics in the Department of Agricultural and Biosystems Engineering and the BIO5 Institute. I completed a BA in Biological Sciences from the University of Missouri-Columbia and my PhD in Plant Pathology from University of Arizona’s School of Plant Sciences. Keywords: plant-microbe interactions, comparative genomics, microbial ecology, fungal endophytes

Dr. Schlenke's research program uses fruit flies in the genus Drosophila to understand the evolutionary genetics of host-parasite interactions. For example, his lab has developed several species of parasitic wasps, which are readily observed infecting Drosophila in nature and can be very specialized to particular host species, as model parasites. These wasps lay single eggs in Drosophila larvae and, once hatched, consume flies from the inside out. Flies mount cellular and behavioral defense responses against wasps, but wasps have adaptations for finding host fly larvae, suppressing host cellular immunity, and manipulating host behavior. The Schlenke lab uses a variety of "omics" tools to understand the molecular genetics of fly cellular immunity and wasp virulence, as well as patterns of host immunity and pathogen virulence coevolution across fly and wasp phylogenies. The Schlenke lab also studies the genetics and neurobiology of behaviors that flies use to avoid being infected by the wasps and to cure themselves once they are infected, including various self-medication behaviors.

Marc Orbach, PhD, uses Magnaporthe grisea, the fungal pathogen responsible for the rice blast disease, as a model system to study host-pathogen interactions at the molecular and biochemical level. This pathogen, like many other plant pathogens, interacts with its host in a gene-for-gene manner, where host resistance is induced when the plant contains a resistance gene and the pathogen, a corresponding avirulence gene. The main focus of his research program is to understand what the signals between the pathogen and its host are, that dictate whether the host is able to mount a resistance response. Genetic analysis of M. grisea have identified several avirulence genes that determine what their products are and how these products interact with host plants to induce host defenses. He is also interested in questions of genome stability and the generation of genetic variability in fungi. These questions are of significance in M. grisea because of the apparent ability of this pathogen to rapidly overcome host resistance in the field. Dr. Orbach spends time addressing these questions by studying genome variation in M. grisea at the whole genome level using electrophoretic karyotyping methods. He wishes to specifically analyze the role that a transposable element may play in genome variation and the high rate of mutation observed at some loci.

Our lab investigates how the ecology of a species shapes patterns of variation at multiple levels (genes, pathways, transcriptomes, genomes, physiology, behavior and life history), how populations adapt to environmental shifts (natural or human created), how genetic architecture can dictate the evolutionary trajectory of populations, the implication of ecological adaptation in the process of speciation and the role of sexual selection and sexual conflict in the evolution of reproductive incompatibilities. Our research revolves around these fundamental aspects of evolutionary biology. We work on a group of cactophilic Drosophila that inhabit the deserts of North America. These Drosophila species are an excellent system to study given that their ecology is well understood and the fact that we can perform many genetic, genomic, manipulative and life history experiments. In addition to utilizing the cactophilic Drosophila system we have ongoing projects on the agrigenomics of the agricultural pests, Drosophila suzukii (spotted wing Drosophila) and Helicoverpa zea (corn earworm). Keywords: Evolutionary, ecological and agricultural genomics

Dawn H. Gouge, PhD, is a Specialist and Professor at the University of Arizona, College of Agriculture and Life Science, Department of Entomology. Dr. Gouge is well established in the U.S. as a community Integrated Pest Management expert and works with international partners in several countries. Dawn has published 38 original research papers and more than 80 extension publications, many in collaboration with investigators from around the world, authored 4 book chapters and co-edited a definitive Pest Management Strategic Plan. Dr. Gouge is a frequent presenter at national and international meetings, and serves as a steering committee organizer of the International IPM Symposium conference. Dawn has received11 awards for outstanding achievement and provides service on both National and Federal advisory committees. Dr. Gouge has led the charge in establishing higher pest management standards in children’s environments, reducing risks associated with pest and pesticide exposure. Keywords: arthropod vectors, bed bugs, Integrated pest managment

Judith L. Bronstein is University Distinguished Professor of Ecology and Evolutionary Biology, with a joint appointment in the Department of Entomology. Dr. Bronstein’s large, active lab focuses on the ecology and evolution of interspecific interactions, particularly on the poorly-understood, mutually beneficial ones (mutualisms). Using a combination of field observations, experiments, and theory, they are examining how population processes, abiotic conditions, and the community context determine net effects of interactions for the fitness of each participant species. Specific conceptual areas of interest include: (i) conflicts of interest between mutualists and their consequences for the maintenance of beneficial outcomes; (ii) the causes and consequences of "cheating" within mutualism; (iii) context-dependent outcomes in both mutualisms and antagonisms; and (iv) anthropogenic threats to mutualisms. In addition, she is Editor-in-Chief of The American Naturalist, a leading international journal in ecology and evolution. An award-winning instructor, Dr. Bronstein teaches at both the undergraduate and graduate levels; she has also run a large training grant administered by BIO5 that places life sciences graduate students in public school classrooms around Tucson. She serves in leadership positions in the College of Science (including chairing the College of Science Promotion and Tenure Committee for 2013), at the University, and at the Arizona-Sonora Desert Museum, where she is a member of the Board of Trustees and Chair of the Science and Conservation Council.

Judith Becerra, PhD, is an evolutionary ecologist interested in insect-plant interactions. Her current research combines ecological, biogeographycal, and chemical information with molecular phylogenetics to identify macroevolutionary patterns of host shifts, co-adaptive forces shaping coevolution and evolutionary strategies of plant chemical defenses. She is also interested in plant and insect diversification and ecological chemical interactions between insects and plants. Extensive research has been pursued in the Mexican tropical dry forests with the plant genus Bursera and their herbivores, the beetle genus Blepharida. These two groups have interacted for the last 100 million years and are both highly diverse, with spectacular adaptations and counteradaptations.

Michael Barker is an evolutionary biologist studying the origins of biological diversity, particularly how abrupt genomic changes such as polyploidy, chromosomal change, and hybridization have contributed to the evolution of plant diversity. Biologists have long been fascinated by these processes because they create unique opportunities for the evolution of ecological and phenotypic novelty with the potential for relatively rapid speciation. Although assessing the importance of these abrupt changes has historically been a difficult task, advances in genomics and bioinformatics have created new opportunities for addressing these longstanding questions. By integrating new computational and evolutionary genomic tools with traditional approaches such as molecular evolution, phylogenetics, mathematical modeling, and experimental work Barker's lab currently studies 1.) the contributions of recent and ancient polyploidy to eukaryotic diversity; 2.) the evolution of chromosome number and genome organization; and 3.) the impact of hybridization on speciation and novelty.

A more complete understanding of microbial processes and patterns is essential in order to understand the relationships among ecosystem functions, global change, and management of natural and working landscapes. Our research focuses on bridging the gap between the disciplines of general ecology and microbial ecology by analyzing large and complex molecular datasets.