The Mountain Lake Biological Station is a remote mountaintop research and teaching facility in the Appalachian Mountains of southwestern Virginia. It was established in 1929 as a branch of the Biology Department at the University of Virginia for research and advanced training in field biology. As Associate Director since 1996 I coordinate research at the station, administer and run the NSF-funded Research Experiences for Undergraduates program (REU), developed, administer, and maintain the station's computer network, serve as data manager and web master, manage and maintain equipment, plan long-term projects, host visiting groups, organize the summer seminar series, represent the station in national and regional organizations (e.g. OBFS, NEON), oversee laboratory safety and animal care issues, and PI grants to the station.

Many plants are capable of hybridizing between species and even genera. Hybridization can cause increases in genetic diversity, create novel gene combinations, transfer adaptations from one taxon to another, break down or build up reproductive barriers, and create wholly new taxa. There is little doubt that hybridization between plants, especially when followed by geographic or reproductive isolation, represents enormous evolutionary potential and has been responsible for the evolution of a large number of species. Effective gene flow between plant populations requires migration (via seed or pollen), establishment and reproduction. The ecological and evolutionary dynamics of gene exchange are the subjects of my research.

Restrictions to gene flow between taxa can occur at two levels. First: local environmental selection may favor a native over an immigrant genome, and reproductive barriers can reduce effective gene exchange between them. Second: the distribution of potential mates (population diversity and density) may determine the mating options and individual immigrant fitness, especially since immigrants are often rare. This frequency- and density-dependent selection may be as important as, and interact with, environmental selection in controlling gene flow between divergent populations. I have studied how environmental and frequency-dependent selection, along with pollinator mediated selection and reproductive biology in Gilia capitata (Polemoniaceae), affect hybridization between two of its subspecies. I continue to pursue similar questions in the Monarda clinopodia / fistulosa , Silene virginica / caroliniana and Dryopteris intermedia / campyloptera hybrid systems.

Organization of Biological Field Stations (OBFS, obfs.org)

• Board of Directors, 2000 – pres.
• Chair, Governance Committee, 2006 – pres.
• Past-President, 2004 – 2006
• President, 2002 – 2004
• Vice President, 2000 – 2002
• Annual Meeting Host, 1999
• Member Station Representative, 1996 - pres.

• Board of Directors, 2006 – pres.
• Finance Committee, 2006 – pres.
• "Year of Science" Committee, 2007– pres.
• Council Member and OBFS Representative, 2002 – pres.

National Ecological Observatory Network (NEON, neoninc.org)

• Voting Member and AIBS Representative, 2007– pres.
• “Red Team Review”  6-7 April, 2006, Washington, D.C.
• Consortium Development Committee, NEON Design Consortium, 2004 – 2005
• Steering Committee, Infrastructure for Biology at Regional to Continental Scales (IBRCS), 2002 – 2004

Mid-Atlantic Region Ecological Observatory (MAREO, mareo.org)

• Co-Leader, 2003– 2006
• Chair, Facilities Committee, 2003 – 2006
• Representative, Consortium of Regional Ecological Observatories (COREO), 2004 – 2006.

SouthEast Regional Network of Expertise and Collections (SERNEC, an initiative of The Society of Herbarium Curators)

• Steering Committee, 2005 – pres.

Resource Discovery Initiative for Field Stations (NSF Project)

• Steering Committee, 2002 – 2006

Wilderness Conservancy at Mountain Lake

• Advisory Board, 2001 – pres.
• Environmental Consultant, 2000 and 2007

• Chair, Arboretum and Landscape Committee (link), Office of the Executive Vice President, 2007 – pres.
• Arboretum and Landscape Committee (link), Office of the Executive Vice President, 2002 – pres.
• Committee on Public Art, Office of the Executive Vice President, University Committee
  Member 2007 – pres.
• Faculty-Student Mentoring Program (link), Office of African American Affairs, 2003 – pres.