Current Research Projects

NSF Collaborative Research: Evolutionary reversals in hormonal modulation of growth-regulatory gene networks.
With Bob Cox (Univ. Virginia) and Christian Cox (Florida International Univ).  Investigating evolutionary reversals in the effects of testosterone on growth and the expression of growth-regulatory gene networks in Sceloporus spp. and closely related lizards marked by opposite patterns of sexual size dimorphism, where females grow faster to become larger than males in some species while the opposite occurs in other species.  Early data indicate that many of the underlying growth-regulatory genes are upregulated and stimulated by testosterone in males of male-larger species and down-regulated in males of female-larger species.

USDA-NIFA Hatch/Multi State: Agrochemical effects on human and environmental health: mechanisms and mitigation.
Investigating the dualism of testosterone as a growth inhibitor in some species of lizards and a growth stimulator in others.  The objective is to develop a comprehensive understanding of growth regulation focused on modulation of gene expression.  The longer-term aspirational goal is to inform the development and application of highly focused agrochemicals to alleviate unintended impacts on the health and well-being of wildlife species. New information discovered in this project may also serve to sharpen the focus of agrochemicals developed for intended effects on animal production.

George H Cook Honors Research (Ralph Good Award): Effects of forest thinning on the diversity and abundance of ticks and the prevalence of tick-borne pathogens in the New Jersey Pinelands  Reserve.
With Julia Brennan (George H Cook Scholar) and Dina Fonseca, Director, Rutgers Center for Vector Biology in collaboration with Mike Gallagher, USDA Forest Service.  In replicated thinned and unthinned forest plots at sites in the pinelands, investigating effects of thinning on forest structure, microclimate, the abundance and species diversity of ticks and their hosts, and the prevalence of tick-borne pathogens.

George H Cook Honors Research: Habitat selection models to predict the abundance, distribution, and overlap of Eastern fence lizards (Sceloporus undulatus) and red chigger mites (Eutrombicula alfreddugesi).
With Adam Yawdoszyn and Connor Anderson (George H Cook Scholars), Juan Bonachela (Rutgers Dept. Ecology, Evolution, and Natural Resources), and Lisa McManus (Hawaii Institute of Marine Biology).  Investigating how easily-parameterized habitat characteristics can be used to develop habitat selection models for fence lizards and to predict the intensity of chigger mite ectoparasitism on lizards.

George H Cook Honors Research: Tolerance of Ectoparasitism in Eastern fence lizards (Sceloporus undulatus).
With Hailey Conrad (former George H Cook Scholar) and Nick Pollock (Univ. Texas – Arlington).  Investigating ecological exposure and physiological susceptibility of Eastern fence lizards to chigger mite ectoparasitism.  Even though individual lizards can be parasitized by more than 400 chigger mites at a time, ecological and physiological costs of these prodigious intensities of ectoparasitism are elusive, suggesting that fence lizards have evolved essentially infinite tolerance of the annoying but innocuous chigger mites.

Past Research Projects

USDA McIntire Stennis: Coarse woody residue decomposition affected by southern pine beetle: fungal interactions influencing fire hazard in the NJ pine barrens.
With Ning Zhang (Plant Biology & Pathology, SEBS) and Matt Ayres (Dartmouth). Investigating the effects of wood invasion by southern pine bark beetle and the fungi introduced by them on the rate of decomposition of infested wood and changes in fungal succession on beetle damaged and non-beetle wood.

USDA McIntire Stennis: The role of Acidobacteria Communities in Carbon and Nitrogen Cycling Processes in New Jersey Pineland Soils.
With Max Haggblom (Biochemistry and Microbiology, SEBS) and Le Kerkoff (IMCS, SEBS). Understanding the edaphic factors affecting abundance of Acidobacter and it role in C cycling in pine barrens forests.

USDA McIntire Stennis: Impacts of Forest Thinning and Soil Disturbance on Sustainability in the NJ Pine Barrens.
This project, conducted at the New Jersey Conservation Foundation Parker Preserve,  involves a thinning and forest floor manipulation experiment following the ecological changes associated with replacement of ericaceous understory with a graminoid understory in the thinned forest. It is thought that this may have been the structure of these forests in pre-colonial times. The experimental manipulations  is investigating nutrient and carbon dynamics, tree performance and the success of generating a mixed species graminoid community from seed bank or by seeding with and without mycorrhizal inoculation.

Mesocosm studies of the effects of prescribed burning and forest floor disturbance.
This project takes some of the components of the Parker Preserve project (above) in combination with burning to follow the fate of soil nutrients with forest floor manipulations of burning, soil disturbance and understory vegetation removal. The experiment is set up under replicated individual trees within the field station property.

Influence of gypsy moth defoliation on carbon dynamics and nutrient dynamics in soil.
This project has arisen from three successive years of gypsy moth attack. In combination with the Forest Service, we have looked at the stand net carbon budget using eddy flux data. We are looking at the changes in chemistry of consumed leaves and the new flush of leaves post attack as well as decomposition of and mineralization from decomposing frass.