Ecology, Evolution and Behavior

My research is focused on the physiological ecology of reptiles.
On-going projects include:

• Evolution of viviparity (live-bearing). My focus is on the morphological and physiological features that enhance or retard the ability of females to extend egg retention beyond the normal stage at which eggs are laid
• Impact of incubation temperature on development. My focus is on both embryonic development and on the morphology and behavior of individuals after hatching.

J. E. “JEB” BARRETT (jebarre@vt.edu)

My research addresses the influences of soils, climate variability, hydrology and biodiversity on ecosystem processes from the scale of microorganisms to regional landscapes. Presently, most of my research is conducted in Polar desert ecosystems of Antarctica where I am focusing on how subtle changes in climate affect carbon cycling through altered processes meditated by soil organisms. In other ongoing projects I am studying the roles of physicochemical gradients and microorganisms in facilitating transformation and transport of nitrogen-compounds across terrestrial-aquatic interfaces.

Research in the Belden lab is focused on general aspects of amphibian ecology, physiology and behavior and also on understanding ongoing worldwide declines in amphibian populations. Our current emphasis is on investigating the role of environmental stress in regulating disease outbreaks in amphibian populations.

member: Integrative Behavioral and Organismal Biology

My major research interests include contemporary and historical effects of disturbance (logging, agriculture and/or urbanization) to stream structure and function, and long-term recovery of streams from watershed disturbance. My students generally focus on research questions involving biodiversity and/or stream ecosystems level processes.

member: Stream Team

Cherry Lab - Dr. Don Cherry (email)

• Mercury Contamination in the North Fork Holston River, Saltville, VA
• In situ Chronic Toxicity Tests with the Asian Clam
• Laboratory Toxicity Tests with the Mayfly, Isonychia bicolor
• Abandoned Mine Lands/Acid-Mine Drainage Impacts in the Powell River Watershed
• Coal Mining Hollow Fill Influence upon Head Water Streams
• Toxic Thresholds of Conductivity, TDS and trace metals from Coal Mining Effluents

Hawley Lab - Dr. Dana Hawley (HawleyD@vt.edu)

Research in the Hawley Lab investigates wildlife disease ecology from molecular, behavioral, and physiological perspectives.  Current lab projects include the influence of genetic diversity on disease susceptibility, how social stressors mediate individual physiology and disease response, environmental toxicology and immunity, and pathogen-induced behavioral changes. Our multi-disciplinary research interests also extend to basic questions of vertebrate (primarily avian) ecology, behavior, physiology, and genetics.

Our lab is involved in the use of gene sequences in understanding the big picture of angiosperms (flowering plants) evolution. We also are involved in detailed evolutionary studies of the grass and waterlily families. Another aspect of our research involves understanding molecular evolution of a multigene family that encodes the seed storage protein prolamin. We also have special interest in the systematics, evolution and genetic diversity of crop plants with a focus on cereal crops, peanut and cowpea.

Jenssen Lab - Dr. Thomas Jenssen (email) (Emeritus)

For the past 35 years, anoline lizards have captured my curiousity, leading me into the investigation of their behavioral ecology. In particular, Anolis signalling systems have been a primary research interest. My belief that adaptive inference can best be drawn from free-ranging subjects has taken me to study sites throughout the Caribbean, Mexico, Central America, Hawaii, and southeastern US. Currently, I am investigating the interactions of life history traits, morphology, social strategies, and display behavior of Anolis carolinensis as expressions of sexual selection.

I study interactions between plant roots and the soil environment, and how these interactions influence plant establishment, growth, competition, succession, and ecosystem productivity. My recent work is focusing on nutrient foraging behavior and how species with different behaviors deal with spatial heterogeneity of nutrients and water. My lab uses a combination of field experiments, greenhouse studies, and simulation modeling to test basic ecological theories and to determine optimal approaches for upland hardwood restoration.

Endocrine Disruption by Environmental Chemicals, Developmental Endocrinology

member: Integrative Behavioral and Organismal Biology

Our research is focused on providing an integrative understanding of how animals function in their social and physical environment. As such we study animals from variety of habitats (Arctic to the Tropics) and from a variety of perspectives including physiological function, neuroendocrinology, ecology, evolution, and behavior.

member: Integrative Behavioral and Organismal Biology

Our research is focused on the mechanisms by which plants acclimate and adapt to environmental variation. The mechanisms of adaptation, acclimation, or interaction are studied at many different scales (biochemical, physiological, anatomical, whole plant, population,etc). Currently our research concerns are;

• competition between native and invasive species,
• inhibition of canopy recruitment by subcanopy shrubs
• constraints of freeze-thaw and drought on vascular anatomy and water relations of Rhododendron species
• the association between latitude and leaf structure-function in the genus Rhododendron.

Our research uses morphological and molecular characters to construct phylogenies and address questions of phylogeography. We also study changes in the stickiness and mechanical properties of spider capture threads that were associated with the evolution of orb-weaving spiders and investigate the mechanism of stickiness that operates in primitive, cribellar capture threads.

Orientation/Migration (navigation, magnetoreception, cue integration, polarized light detection), Sexual Selection (coevolution of color signals & chromatic processing mechanisms, origins & evolutionary consequences of sensory 'biases'), Visual Ecology (ultraviolet & extraocular photoreception in vertebrates).

member: Integrative Behavioral and Organismal Biology

My laboratory pursues two lines of research: Using molecular tools, we analyze the population structure of fish species with unusual reproductive systems. Most of our recent work has been on the evolution of outcrossing in Kryptolebias marmoratus, the only known self-fertilizing vertebrate. We also study the relationship between ecological divergence and the evolution of reproductive isolation in fish species flocks. Our recent work has been with a little-known group of "pupfishes" (Cpyrinodon) from San Salvador island, where we have found that reproductive isolation among sympatric morphotypes has evolved in less than 4000 years.

My research focuses on ecosystem ecology and biogeochemistry. I use stream and groundwater environments to learn more about the structure and function of open ecosystems with emphasis on the biogeochemistry of nitrogen (N), carbon, and phosphorus. I collaborate with Jack Webster and Fred Benfield to form the Virginia Tech Steam Team. My own research addresses N transformations in surface and groundwater environments focusing primarily on the implications of terrestrial-aquatic interactions.

member: Stream Team

Current Research:

• Evolution of cooperative breeding in birds
• Ecological basis of sensitivity to habitat fragmentation
• Evolution of social behavior and life history in birds and primates
• Conservation of endangered birds
  

member: Integrative Behavioral and Organismal Biology

I collaborate with Fred Benfield and Maury Valett as the Virginia Tech Steam Team. Together we have a breadth of research in stream ecology with a variety of research projects funded primarily by NSF. My own research concerns nutrient and organic matter dynamic in stream ecosystems. I'm also interested in computer modeling of streams.

member: Stream Team