Education & Employment History Adjunct Professor 2010-11 University of Virginia (Mountain Lake Biology Station) Adjunct Professor 2007 University of Kwazulu-Natal (South Africa) Professor 2005-Present Georgia Southern University Associate Professor 2000-05 Georgia Southern University Assistant Professor 1995-2000 Georgia Southern University Postdoc 1992-94 Hebrew University of Jerusalem, Israel. (with Avi Shmida) Postdoc 1990-92 University of California at Santa Barbara. (with Susan Mazer) Ph.D. 1990 University of Illinois. (advisor = May Berenbaum) M.Sc. 1985 University of Toronto. (advisor = Spencer Barrett) B.Sc. 1981 McGill University

My research program focuses on plant evolutionary ecology and the biology of invasive species. I am interested in how evolutionary forces such as genetic drift and natural selection resulting from positive (eg: plant-pollinator) and negative interactions, (eg: plant-pathogen) influences patterns observed in natural populations of angiosperms. I currently have an active lab of undergraduate and graduate students working on a diversity of research topics in the southeastern coastal plain, the Appalachian Mountains, Europe and China.

Ecological Genetics of Plant Invasions

Owing to their ecological and economic costs, a primary goal of research on alien species is to understand the factors responsible for successful invasion. It is commonly noted that individuals in the introduced part of a species' geographic range exhibit increased vigor when compared to plants in the native range. This pattern could arise if ecological conditions in the new environment are different from the native range (e.g., absence of natural enemies). Alternatively, differential performance could arise from genetic changes following invasion. The goal of my research is to examine ecological and genetic aspects of the invasion process in plants. and economic costs, a primary goal of research on alien species is to understand the factors responsible for successful invasion. It is commonly noted that individuals in the introduced part of a species' geographic range exhibit increased vigor when compared to plants in the native range. This pattern could arise if ecological conditions in the new environment are different from the native range (e.g., absence of natural enemies). Alternatively, differential performance could arise from genetic changes following invasion. The goal of my research is to examine ecological and genetic aspects of the successful invasion of Silene latifolia into North America from Europe.

Pollination Syndromes

Hermaphroditic flowers disseminate and receive pollen and therefore represent a compromise in selection pressures that operate on male and female function. My studies on temperate, desert and tropical plant-pollinator systems have focused on how intra-population variation in floral morphology influences sexual function. I am particularly interested in the pollination syndrome concept which argues that floral traits (eg, size, color, shape) coexist in predictable combinations to interact with different suites of pollinators. We are using the large group of morning glory (Ipomoea) species that grow sympatrically in the southeastern coastal plain to test the validity of the pollination syndrome concept. A new direction we are adopting is to use transgenic I. quamoclit (blue vs. red flowers) to evaluate how variation in a single trait (flower color) impacts pollinator attraction.

The Biology of Mutualistic and Antagonistic Relationships

Plants in nature not only interact with mutualists (eg, pollinators), but also have to deal with antagonistic interactions with pathogens, herbivores and competitors. These interactions can result in opposing selection forces if traits that favor mutualism work in opposition (eg, while large flower size attracts pollinators it may also attract floral herbivores). Ongoing projects in the lab are examining: 1) how pollination syndromes influence floral herbivory in sympatric morning glories, and; 2) the causes and consequences of fungal pathogen disease in natural populations of flame azalea (Rhododendron calendulaceum), a native forest understory forest tree in mountains of the eastern US.

Environmental Biology
This course is designed to introduce non-major students to contemporary issues of environmental biology. A mix of lecture and discussion is used to challenge students to understand how topics such as human population growth, global climate change, rapidly evolving global politics, and emerging diseases are, and will influence their lives.

Evolution
This undergraduate/graduate level course presents an introduction to the world of evolutionary biology in which we explore the history of evolutionary thought and how the major evolutionary forces (natural selection, genetic drift) generate change at various levels of organization.

The Music of Bruce Springsteen
For 40 years Bruce Springsteen has been writing about the hopes, dreams and realities of life. This First-Year Experience course integrates a variety of media and strategies to understand how his lyrics and live performances have impacted American culture and society.

Plant-Animal Interactions
The relationship between animals and plants provides some of the most compelling examples of biological interactions. This course explores evolutionary and ecological aspects of these interactions by focusing on both mutualistic (e.g., pollination, seed dispersal) and antagonistic (e.g., herbivory) processes. These fundamental interactions are studied by integrating natural history, theory, field experiments, and discussions of the current scientific literature.

Sarah Osborn. Pollination impacts of flower color variation in transgenic Ipomoea quamoclit.

Juliette Jordan. 2011. Quantifying maternal effects in the invasive plant Silene latifolia.

Melany Hardy. 2009. Pattern of phenotyopic variation in Silene latifolia, an invasive species

Brandy Penna. 2006. Pollination limitation in European and North American Silene latifolia.

Lindsay Heaton. 2004. The role of hybridization in a biological invasion.

Amy Blair. 2003. Evolutionary processes in a biological invasion: an experimental study with Silene latifolia.

Daniel Parrish. 2002. Ecological genetics of plant invasions.

Dexter Sowell. 2001. Testing the concept of pollination syndromes using Ipomoea spp.

David Abbott. 2000. Consequences of flower size variation in four sympatric Ipomoea species.

Andrea Whatley. 1999. The ecological and evolutionary dynamics of floral polymorphisms in Linaria canadensis.

• David Abbott - Seed size variation in Ipomoea coccinea and I. quamoclit.
• Micheal Anglin - Prey capture rates in carnivorous pitcher plants.
• Ashley Bonner A comparison of life history traits in invasive and native Ipomoea species.
• Brooke Brandenburg - Gender-based differences in the use of cell phones in Homo sapiens
• Janna Brown Density-dependent survival in European and N. American Silene.
• Jada Carter - A comparison of flower traits between European and North American populations of an invasive plant.
• Amy Craven Performance differences between wild and transgenic Ipomoea quamoclit
• Brian Davis - Pollinator faunas of four morning glory species.
• Wendy Denton - Floral polymorphisms in Linaria canadensis.
• David DeShazo Biomass allocation strategies in the sexes of Rumex.
• Christina Dulock - Pollinator choice at a floral buffet of morning glories.
• Abraham Freiji - The evolution of mating incompatibility in an invasive plant
• Christina Futch - A systematic cleanup of confusing Ipomoea species.
• Lisa Goolsby - Distyly in Israeli populations of Linum mucronatum.
• Jodie Griffin Sex ratio evolution in Rumex.
• Kristin Kelly - The relationship between population size on sex ratios in Rumex.
• Joanne Kendrick - Sex ratios in dioecious populations of Rumex.
• Emily Kuhnlein - Effect of seed morphology on dispersal in pines.
• Nadine Lebedick - Nectar production in four morning glory species.
• Rachel Maynard Evolution of competitive ability in an invasive plants.
• Erin Merritt - The influence of life history variation on allocation strategies in morning glories.
• Katrina Motes - Prey capture rates in pitcher plants.
• Colleen Murphy - Morph frequencies in polymorphic Linaria canadensis.
• Chris O'Neil - Do pollination syndromes exist? Testing the dogma with a suite of Ipomoea species.
• Brent Paige - Herbivory on the flowers of four morning glory species.
• Danielle Prestifilippo Evolution of density-dependent survival in Silene
• Catherine Prior - Nectar production in the floral morphs of Gelsemium sempervirens.
• Jeremy Rayfield - Population variation in morph frequencies in the distylous Gelsemium sempervirens.
• Susan Sellers - Floral polymorphisms in Linaria canadensis.
• Bethany Smith Maternal effects in the invasive plant, Silene latifolia
• Becky Smyth - Distyly in Israeli populations of Linum mucronatum.
• Kimberly Stewart - Seed size variation in Ipomoea coccinea and I. quamoclit.
• Paul Uribe - Phenological flowering patterns in sympatric morning glories.
• Brian White Evolution of competitive ability in an invasive plants.
• Kimberley Wollett. Sexual destruction: the seedier side of plant-animal interactions.
• Jennifer Krstolic. 1997. Valparaiso University. The role of symmetry on variance in flower size in angiosperms. NSF REU PROGRAM.
• Janna Brown. 2009. Georgia Southern University. Genetic determinants of success in colonizing populations. NSF REU PROGRAM

Department of Biology, Georgia Southern University

last modified: 8/21/12