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Jennifer Rudgers Associate Professor Associate Professor of Ecology and Evolutionary Biology e-mail:[email protected] B.S. Environmental Science (1996) Denison University, Granville, OH Ph.D. Population Biology (2002) University of California, Davis, Davis, CA Department Affiliations Center for the Study of the Environment and Society Institute of Biosciences and Bioengineering Websites Rudgers Rudgers-Whitney Lab Jenn Rudgers Research Areas Ecology and evolution of interactions among plants, animals, and microbes; community ecology of mutualisms; evolution of vertically transmitted symbionts Current Research Interests My research integrates community ecology with evolutionary biology to explore the ecological dynamics and the evolutionary consequences of interactions among plants, animals and microbes. Plants interact with other community members through both direct and indirect pathways. For example, plants are directly attacked by herbivores but may gain indirect resistance to herbivory from the predators of herbivores or from microbial mutualists, such as endophytic fungi. Considering plants in the context of the whole ecological community can improve our understanding of factors that govern their distribution and abundance. We may also uncover novel ways in which multiple species interact to affect the evolution of plant traits. Throughout my research, I strive to tackle questions with both conceptual and applied significance. Advanced knowledge of the importance of multi-species interactions in both natural and managed ecosystems can help us to make better predictions about the ecological and evolutionary consequences of environmental change. Do indirect interactions influence plant evolution? Plants possess a number of strategies to defend against herbivory, including attracting the predators and parasitoids of their herbivores ¿ an indirect defense. Research has largely focused on direct interactions between plants and herbivores, with less consideration of the role of indirect interactions in plant evolution. To examine selection on indirect defense, I used a wild species of cotton (Gossypium thurberi), which bears extrafloral nectaries that attract ants (see photo). The ants consume and disturb herbivores, thereby increasing cotton fitness. Unlike some of the ant-plant mutualisms made famous by Janzen and others, the ant-cotton association varies in the degree to which ants are beneficial. It is therefore more representative of the complex and variable indirect interactions that typically occur between plants and predators. By combining quantitative genetics techniques with field experiments that altered ant and herbivore densities, I showed that extrafloral nectary traits exhibit heritable variation, that ants increase plant fitness by reducing herbivory, and that the availability of extrafloral nectar mediates the benefits of ants (Rudgers 2004, Ecology). What is the relative importance of consumptive versus non-consumption interactions in predators' control of prey? In addition, work with wild cotton suggests that ants may be an overlooked resource in the biological control of cultivated cotton pests. The mechanisms by which ants benefit wild cotton are not exclusively through their consumption of herbivores. Ants also cause herbivorous caterpillars to drop from leaves and reduce their feeding rates. In fact, ants confer greater benefits to plants by modifying herbivore behavior than by consuming caterpillars (Rudgers et al. 2003, Oecologia ). Do plants face trade-offs in allocating among anti-herbivore defense traits? In exploring the evolutionary consequences of indirect interactions, it is important to consider how selection on one plant trait, such as extrafloral nectar production, may constrain the evolution of other traits. In collaboration with Sharon Strauss and Jonathan Wendel, I tested for constraints on defensive traits in the cotton clade (Gossypieae). Using a recent phylogeny to control for shared ancestry, we found that direct plant defenses (toxic leaf glands and leaf hairs) and the indirect defense of extrafloral nectar appear to evolve independently in the Gossypieae, a pattern that may reflect the facultative nature of indirect defense (Rudgers et al. 2004, Am. J. Bot.). How does geographic variation in species interactions affect coevolution? Experiments conducted in multiple populations of wild cotton revealed that the defenses conferred by ants varied geographically. Recent theory on coevolution has embraced this commonly observed biological reality: the outcomes of species interactions vary across space. Understanding how this spatial variation affects selection will enhance our ability to predict how species traits are shaped by coevolution. By experimentally manipulating the putative agents of selection (ants) in three populations, I showed that ants were responsible for geographical variation in selection on extrafloral nectary traits . This work is some of the first to manipulate interactions experimentally across multiple sites and thereby document that geographically variable selection, mediated by a mutualist, can shape the evolution of plant traits (Rudgers and Strauss 2004, Proc. Roy. Soc.). How important is plant genetic variation to the distribution and abundance of species? In addition to investigating factors that affect genetic diversity within plant populations, I am also interested in the ecological consequences of this genetic diversity, specifically how the loss of diversity influences the ecological community. Because a nthropogenic disturbances and agricultural monocultures often reduce diversity, an understanding of the ecological function of diversity (including both species diversity within communities and genetic diversity within species) can inform ecosystem conservation. For this question, I used the shrub Baccharis pilularis, which has an architectural dimorphism with both prostrate and upright genotypes. The two genotypes sustain different ecological interactions in coastal California . My experiments showed that only the prostrate genotype facilitates the establishment of another dominant, coastal shrub, Lupinus arboreus (Rudgers and Maron 2003, Oikos). This is one of the first studies to suggest that plant genotype is important to facilitative interactions between plants, revealing the potential for facilitation to affect plant evolution. In addition, a four-year herbivore exclusion and common garden experiment showed that the two genotypes support different assemblages of insect herbivores. This differential herbivory, in turn, may affect the maintenance of the dimorphism within the Baccharis population (Rudgers, in prep.). These studies confirm the importance of population-level genetic diversity to both plant and arthropod communities. I have conducted similar work with ants and cotton, addressing whether variation among plants in the amount of extrafloral nectar affects the diversity of an arthropod assemblage (Rudgers and Gardener 2004, Ecology). What factors affect the dynamics of plant-microbe symbioses? Populations of grasses vary in the frequency of endophyte infection. Our work has demonstrated that factors extrinsic to the grass-endophyte symbiosis, namely mammalian and insect herbivores, explain significant variation in the long-term dynamics of plant-microbe symbioses. In experimental populations composed of 50:50 mixtures of infected and uninfected plants, we found a greater increase in endophyte frequency (from 50% to 80%of plants infected) under ambient levels of herbivory than when herbivory was experimentally reduced (from 50% to 62%) (Clay et al. 2005, PNAS). Brief Statement of Research Interests Ecological theory has traditionally held that abiotic factors and antagonistic interactions are the primary determinants of population and community dynamics. In contrast, mutualistic interactions, in which both species benefit from their association, have received much less attention. My research program uses plants, arthropods, and microbes to explore how mutualistic interactions affect population dynamics, community structure, and evolution. Mutualistic microbes, in particular, contribute an important, but often overlooked, layer of diversity in ecosystems, and their inclusion in ecological research can increase the realism of both experiments and theory. Throughout my research, I strive to tackle questions with both conceptual and applied significance. Advanced knowledge of the importance of mutualisms in both natural and managed ecosystems can help us to make better predictions about the ecological and evolutionary consequences of environmental change. To what extent do positive, indirect interactions affect community and ecosystem dynamics? Theory in community ecology has long emphasized the importance of negative species interactions (competition, predation) in the structure of communities. We know far less about the roles of indirect interactions and mutualisms at the community and ecosystem scale. I have been exploring interactions between microbial endophytes of grasses, which¿like ants¿can provide an indirect defense to their host plant. Fungal endophytes produce alkaloids that can deter many insect and mammalian herbivores, and they occur in the aboveground tissues of an estimated 20-30% of grasses (i.e., 1,600 ¿ 2,400 species). Using both native and invasive, non-native grass systems , my work addresses how endophyte-grass associations influence the diversity and abundance of competing plant species as well as associated arthropods. Although fungal endophytes represent a small fraction of the biomass of communities, we are finding that they can have very strong effects on community structure, by reducing the abundance and diversity of associated plants and arthropods (Rudgers and Clay, 2005) . In addition, endophytes can affect rates of decomposition of infected leaf litter (Lemons et al. 2005, Oecologia). I have also investigated whether microbial mutualists, such as endophytic fungi, can enhance the ability of their hosts to invade diverse plant communities. The biodiversity of a community can affect its functional properties, such as productivity or resistance to invasion. I developed a conceptual model that predicts plants with mutualists will have greater success invading diverse plant communities than plants without mutualists (Rudgers et al. 2004, Ecology Letters). A long-term field experiment and a manipulative greenhouse experiment confirmed this model (Rudgers et al. 2005, Oecologia). Altogether, this work will determine how microbial mutualists contribute to the diversity of natural ecosystems as well as to the success of exotic, invasive grasses. Teaching Areas Insect Biology, Advanced Methods in Ecology and Evolution, Environmental Sustainability and Community Agriculture Selected Publications Abstracts Keller, M. L., Masiello, C. A., Dugan, B. Rudgers, J. A., Capareda, S. C., Hockaday, W. C., and Sun, H. "Phytotoxicity and Plant Productivity Analysis of Tar-enriched Biochars." American Geophysical Union (2008) Refereed articles Chamberlain**, S. C., M. A. Gardener, and J. A. Rudgers. (2012) Trade-offs or synergies among traits for attracting protective bodyguards and pollinators in cotton (Gossypium). Evolutionary Ecology 26: 65-77 Maitner**, BS., JA Rudgers, AE Dunham, and KD Whitney. (2012) Patterns of bird invasion are consistent with environmental filtering. Ecography doi: 10.1111/j.1600-0587.2011.07176.x Rudgers, J.A., Miller, T.E.X., Ziegler, S.M., and K.D. Craven. (2012) There are many ways to be a mutualist: endophytic fungus reduces plant survival but increases population growth. Ecology 93:565-574. Baskett, CA, SM Emery, and JA Rudgers. (2011) Pollinator visits to threatened species are restored following invasive plant removal. International Journal of Plant Sciences 172:411-422. Craig S, S Kannadan SL Flory, EK Seifert, KE Whitney and JA Rudgers. (2011) Potential for endophyte symbiosis to increase resistance of the native grass Poa alsodes to invasion by the non-native grass Microstegium vimineum. Symbiosis 53 (1):17-28 Davitt** AJ, C Chen and JA Rudgers. (2011) Understanding context-dependency in plantmicrobe symbiosis: The influence of abiotic and biotic contexts on host fitness and the rate of symbiont transmission. Environmental and Experimental Botany 71 (2) 137-145 Emery,SM, and JA Rudgers. (2011) Beach restoration efforts influenced by plant variety, soil inoculum, and site effects. Journal of Coastal Research 27: 636-644. Ghimire SR, JA Rudgers, ND Charlton, C Young and KD Craven. (2011) Prevalence of an intraspecific Neotyphodium hybrid in natural populations of stout wood reed (Cinna arundinacea L.) from eastern North America. Mycologia. 103(1):75-84 Gundel, PE, JA Rudgers, CM Ghersa. (2011) Incorporating the process of vertical transmission into understanding of host-symbiont dynamics. Oikos 120:1121-1128 Savage AM, SD Johnson, KD Whitney KD,and JA Rudgers. (2011) Do invasive ants respond more strongly to carbohydrate availability than co-occurring non-invasive ants? A test along an active Anoplolepis gracilipes invasion front. Austral Ecology 36 (3): 310-319 Yule* KM, JB Woolley and JA Rudgers. (2011) Water availability alters the tri-trophic consequences of a plant-fungal symbiosis. Arthropod-Plant Interactions 5:(1) 19-27 *Simao, M. C. M., S. L. Flory, and J. A. Rudgers (2010) Experimental plant invasion reduces arthropod abundance and richness across multiple trophic levels. Oikos 119: 1553-1562 **Crawford, K. M., J. M. Land*, and J. A. Rudgers (2010) Fungal endophytes of native grasses decrease insect herbivore preference and performance. Oecologia 164:431–444 Crutsinger, G. M. S. Y. Strauss, and J. A. Rudgers (2010) Genetic variation within a dominant shrub species determines plant invasion resistance in a coastal dune ecosystem. Ecology 91: 1237-1243 **Davitt, A. J., C. Chen*, and J. A. Rudgers (2010) Understanding context-dependency in plant-microbe symbiosis: the influence of abiotic and biotic contexts on host fitness and the rate of symbiont transmission Environmental and Experimental Botany http://dx.doi.org/10.1016/j.envexpbot.2010.11.004 **Davitt, A. J., M. Stansberry*, and J. A. Rudgers (2010) Do the costs and benefits of fungal endophyte symbiosis vary with light availability? New Phytologist 188: 824-834 Emery, S.M., D. Thompson*, and J. A. Rudgers (2010) Variation in endophyte symbiosis, herbivory and drought tolerance of Ammophila breviligulata populations in the Great Lakes Region. American Midland Naturalist 163: 186-196 Emery, S.M. and J. A. Rudgers (2010) Ecological assessment of dune restorations in the Great Lakes region. Restoration Ecology 18 (S1): 184–194 Emery, S.M. and J. A. Rudgers (in press) Beach restoration efforts influenced by plant variety, soil inoculums, and site effects. Journal of Coastal Research Ghimire, S. R., J. A. Rudgers, N. D. Charlton, C. Young, and K. D. Craven (2011) Prevalence of an intra-specific Neotyphodium hybrid in natural populations of Stout Wood Reed (Cinna arundinacea L.) from eastern North America. Mycologia 103: 74-84 Huguet, V. and J. A. Rudgers (2010) Covariation of soil bacterial composition with plant rarity. Applied and Environmental Microbiology 76: 7665-7667 Rudgers, J. A., A. J. Davitt**, K. Clay, P. Gundel, and M. Omacini (2010). Searching for evidence against the mutualistic nature of hereditary symbiosis: A comment on Faeth (2009). American Naturalist 76: 99-103 Rudgers, J. A., A. M. Savage**, and M. A. Rúa (2010) Geographic variation in a facultative mutualism: consequences for local arthropod composition and diversity. Oecologia 163:985– 996 Rudgers, J. A., S. Fischer*, and K. Clay (2010) Managing plant symbioses: Fungal endophyte genotype alters plant community composition. Journal of Applied Ecology 47: 468-477 **Savage, A. M., S. D. Johnson*, K. D. Whitney, and J. A. Rudgers (in press) Do invasive ants respond more strongly to carbohydrate availability than co-occurring non-invasive ants? A test along an active Anoplolepis gracilipes invasion front. Austral Ecology **Afkhami, M. A. and J. A. Rudgers (2009) Endophyte-mediated resistance to herbivores depends on herbivore identity in the wild grass, Festuca subverticillata. Environmental Entomology 38: 1086-1095 Rudgers, J. A. and S. Orr* (2009) Non-native grass alters growth of native tree species via leaf and soil microbes. Journal of Ecology 97: 247-255 Rudgers, J. A., M. E. Afkhami**, M. A. Rua, A. J. Davitt**, S. Hammer, and V. M. Huguet (2009) A fungus among us: Broad patterns of endophyte distribution in the grasses. Ecology 90: 1531-1539 **Savage, A. M., J. A. Rudgers, and K. D. Whitney (2009) Elevated dominance of extrafloral nectary-bearing plants is associated with increased abundances of an invasive ant and reduced native ant richness. Diversity and Distributions 15: 751-761 Whitney, K. D. and J. A. Rudgers (2009) Constraints on plant signals and rewards to multiple mutualists? Plant Signaling and Behavior 4: 1-4 Afkhami, M. E. and J. A. Rudgers (2008) Symbiosis lost: Imperfect vertical transmission of fungal endophytes in grasses. American Naturalist 172: 405-416 Johnson, S. D.*, K. C. Horn*, A. M. Savage, S. Windhager, M. T. Simmons, and J. A. Rudgers (2008) Timing of prescribed burns affects abundance and composition of arthropods in the Texas Hill Country. Southwestern Naturalist 53: 137-145 Kannadan, S. and J. A. Rudgers (2008) Endophyte symbiosis benefits a rare grass under low water availability. Functional Ecology 22: 706-713 Mack, K. and J. A. Rudgers (2008) Balancing multiple mutualists: asymmetric interactions among plants, arbuscular mycorrhizal fungi, and fungal endophytes. Oikos 117: 310-320 Rudgers, J. A., and K. Clay (2008) An invasive plant-fungal mutualism reduces arthropod diversity Ecology Letters 11: 831-840 Rudgers, J. A. and A. L. Swafford* (2009) Benefits of a fungal endophyte in Elymus virginicus decline under drought stress. Basic and Applied Ecology 10: 43-51 Flory, S.L., J.A. Rudgers, and K. Clay "Experimental light treatments affect invasion success and the impact of Microstegium vimineum on the resident community." Natural Areas Journal, 27 (2007) : 124-132. Rudgers, J.A., J. Holah, S.P. Orr, and K. Clay "Forest succession suppressed by an introduced plant-fungal symbiosis." Ecology, 88 (2007) : 18-25. Rudgers, J.A., and K. Clay "Endophyte symbiosis with tall fescue: How strong are the impacts on communities and ecosystems?." Fungal Biology Reviews, 21 (2007) : 107-124. *Finkes, L. K., A. B. Cady, J. C. Mulroy, K. Clay, and J. A. Rudgers (2006) Plant-fungus mutualism affects spider composition in successional fields. Ecology Letters 9: 347-356 Rudgers, J. A. and K. D. Whitney (2006) Interactions between insect herbivores and a plant architectural dimorphism. Journal of Ecology 94:1249-1260 Tintjer, T. and Rudgers, J. A. (2006) Grass-herbivore interactions altered by strains of a native endophyte New Phytologist 170:513-521 Articles Clay, K., J. Holah, and J. A. Rudgers. 2005 Herbivores cause a rapid increase in hereditary symbiosis and alter plant community composition Proceedings of the National Academy of Sciences of the USA 102: 12465-12470 Lemons, A., K. Clay, and J. A. Rudgers. 2005 Connecting plant microbial interactions aboveand belowground: an endophytic fungus affects decomposition. Oecologia 145: 595-604 *Orr, S. P., J. A. Rudgers, and K. Clay (2005) Invasive plants can inhibit native tree seedlings: testing potential allelopathic mechanisms. Plant Ecology 181: 153-165 Rudgers, J. A., W. B. Mattingly, and J. M. Koslow 2005 Mutualistic fungus promotes plant invasion into diverse communities. Oecologia 144: 463-471 Book chapters Clay, K., K. Reinhart, J. A. Rudgers, T. Tintjer, J. L. Koslow, S. L. Flory. (2008) Red Queen Communities. In: Infectious Disease Ecology: Effects of Ecosystems on Disease and of Disease on Ecosystems. Proceedings of the 11th Cary Conference, May 2005 Editors R. Ostfeld, F. Keesing, V. Eviner. pp. 145-178 Clay, K., Reinhart, K., Rudgers, J., Tintjer, T., Koslow, J. and S. L. Flory (2005) Red queen communities. In: Ecology of Infectious Diseases: Interactions Between Diseases and Ecosystems. (V. Eviner, F. Keesing and R. Ostfeld, Eds.). Princeton University Press Princeton (in press). Rudgers, J. A and K. Clay (2005) Fungal endophytes in terrestrial communities and ecosystems. In: The Fungal Community : Its Organization and Role in the Ecosystem. ( J. Dighton, J. F.White, Jr., and P. Oudemans, Eds.) Third Edition. CRC Press, Boca Raton, pp. 423-442 Presentations Invited Papers Rudgers, J. A. Grass-endophyte symbioses alter plant-herbivore-natural enemy interactions. Organized Oral Section #5618 – The Role of Microorganisms in the Ecology and Evolution of Tri-Trophic Interactions. Ecological Society of America (1-6 August 2010) Pittsburgh, PA. Invited Talks "Symposium Speaker. The International Symbiosis Society, 6th Annual Congress (9-15 August 2009) Madison, WI.." (9-15 August 2009) Panelist Organized oral sessions speaker. "Sex, density dependence and the spread of invasive organisms.." ESA 96th Annual Meeting, Austin, TX. (August 7-12) Posters Yule, K, TEX Miller and JA Rudgers. A vertically transmitted symbiont affects host population dynamics. ESA 96th Annual Meeting, August 7 - 12, 2011, Austin, TX Savage, AM, KD Whitney and JA Rudgers, Can novel mutualisms with native species modify the community-wide consequences of ant invasions? A test using the Anoplolepis gracilipes invasion of the Samoan Archipelago. ESA 96th Annual Meeting, August 7 - 12, 2011, Austin, TX Crawford, KM and JA Rudgers, Rice University. Effects of plant species diversity and genetic diversity on belowground communities and processes. ESA 96th Annual Meeting, August 7 12, 2011, Austin, TX **Afkhami, M. E. and J. A. Rudgers Symbiosis Lost: Imperfect vertical transmission of fungal endophytes in native grasses. Joint meeting of the Mycological Society of America (MSA) and the International Symposium on Fungal Endophytes of Grasses (ISFEG). June 28 – July 1, 2010, Lexington, KY "Fungal endophyte genotypes have community level effects." Ecological Society of America Annual Meeting, Memphis, TN. (August 6-10, 2006) With K. Clay (Indiana University) Seminar Speaker Rudgers, J. A. Small fungi with big impacts: Plant protection mutualisms in complex communities. The Gordon Research Conference in Plant-Insect Interactions. 23 February 2010, Galveston, TX "Community level consequences of endophyte symbiosis." University of Houston Department of Biology, (2008) "Small Fungi with big impacts: the community-level consequences of mutualisms between fungal endophytes and grasses." Texas A&M University Dept. of Entomology, (2008) "Small fungi with big impacts: the community-level consequences of mutualisms between fungal endophytes and grasses." University of Miami, Coral Gables, FLA. (11 Feb 2008) "Small fungi with big impacts: Community-level consequences of mutualisms between fungal endophytes and grasses." Department of Biology, Syracuse University. (November 2-4, 2006) "Small fungi with big impacts: Community-level consequences of mutualisms between fungal endophytes and grasses." Annual Symposium on the Biology of Filamentous Fungi, Texas A&M University. (April 20-21 2006) "Positive Indirect Interations Affect Plant Evolution and Community Structure." University of Tennessee, Ecology and Evolutionary Biology, Knoxville, Tennessee. (2005) "Positive Interactions Influence Plant Evolution and Community Structure." Trinity University, Department of Biology, San Antonio, Texas. (2005) "Positive Interactions Influence Plant Evolution and Community Structure." Haskell Indian Nations University, Department of Biology, Lawrence, Kansas. (2005) Editorial Positions Associate Editor, Oikos. (2011 - 2011) Associate Editor, Oikos. Wiley-Blackwell. (2008 - 2008) Associate Editor, Oikos. (2010 - 2010) Supervised Theses & Dissertations Somereet Nijjer, PhD Understanding belowground community regulation in an invaded forest. (2006) (Committee Member) Michelle E. Afkhami, M. S. Symbiosis lost: Imperfect vertical transmission of fungal endophytes in grasses. (2007) (Thesis or Dissertation Director) Jianwen Zou, PhD Increased competitive ability and herbivory tolerance of the invasive plant Sapium sebiferum. (2007) (Committee Member) Amaris Swann, PhD A Test of Captive Breeding Strategies Using the Housefly, Musca domestica as a Model System. (2008) (Committee Member) Andrew J Davitt, M.S. Understanding novel benefits and costs of grass-endophyte interactions. (2010) (Thesis or Dissertation Director) Andrew J Davitt, MA Mechanisms underlying the costs and benefits in grass-fungal endophyte symbioses. (2010) (Thesis or Dissertation Director) Amy M Savage, Ph.D. Anoplolepis gracilipes invasion of the Samoan Archipelago: Can novel mutualisms with native species amplify ecological impacts?. (2011) (Co-Director) Kerri Crawford, Ph.D. Understanding the combined importance of species diversity and genetic diversity for ecosystem functioning in a sand dune ecosystem. (2011) (Thesis or Dissertation Director) Debbie A Brock, Ph.D. Exploring social interactions among wild D. discoideum clones. (2011) (Committee Member) Scott Chamberlain, Ph.D. Agricultural landscapes alter plant mutualist and antagonist communities. (2012) (Thesis or Dissertation Director) Jeff Ahern, PhD Ecological factors associated with the maintenance of a defensive chemical polymorphism in Xanthium strumarium. . (2012) (Committee Member) Juli Carrillo, Ph.D. Selection for herbivore tolerance in plants: Do herbivores matter?. (2012) (Committee Member) Nik Rasmussen, PhD Consequences of arrival phenology for species interactions. (2016) (Committee Member) Chris Dibble, PhD Intraspecific Priority Effects. (2017) (Committee Member) Christopher Roy, PhD Regional Phylogenetics Along an Environmental Gradient. (2018) (Committee Member) Lukas Bell-Dereske, PhD The effect of symbionts and density on plant community interactions. (2018) (Thesis or Dissertation Director) Yan Yi "Anny" Chung, PhD Stabilizing mechanisms in invaded communities. (Thesis or Dissertation Director) Maria Menza-Lopez, PhD Multiple invasions: Impacts on native communities. (Committee Member) Nick Rasmussen, PhD TBA. (Committee Member) Onja Razafindratsima, PhD TBA. (Committee Member) Awards, Prizes, & Fellowships Phi Beta Kappa Teaching Prize Finalist , Rice University Positions Held Secretary, International Symbiosis Society. (2010 - 2010) Secretary, International Symbiosis Society. (2009 - 2009)