RESEARCH 2017-11-03T18:48:57+00:00

Our Research

Community Ecology of Pine Rockland Plants

The pine rockland ecosystem of south Florida is one of the most critically imperiled ecosystems on earth. Pine rocklands remain on only 2% of their historic range due to habitat fragmentation, fire suppression, and invasive species.  Conservation and restoration of the pine rockland ecosystem requires a multifaceted approach that considers not only habitat restoration, endangered species, and invasive species, but relationships between them. Our research focuses on understanding how fire suppression, invasive species, and fragmentation alter the taxonomic, phylogenetic, and functional diversity in remnant pine rockland fragments. Through a project funded by the Eppley Foundation, we developed a community phylogeny for all pine rockland plants. Currently, we are using this phylogenetic tree to understand how pine rockland plant communities change over space and time in response to anthropogenic drivers in the pine rockland at the UF IFAS Tropical Research and Education Center (TREC) and pine rockalnds in Miami-Dade county. This research is a collaboration with Fairchild Tropical Botanical Garden and Emily Sessa (UF, Biology department). This project is currently funded by the UF/IFAS Dean of Research office.

An integrative approach to quantifying the response of ecological assemblages to anthropogenic stressors

Biodiversity is a multidimensional concept that refers to variation in life forms. While species richness, the number of species in a given location, is commonly used to quantify biodiversity, it does not necessarily reflect the variation in organismal diversity. For example, species may differ in their abundances, ecological function, evolutionary history, and their interaction patterns (e.g., what other species they eat, compete with, or pollinate). Ignoring these differences when assessing the impact of anthropogenic stressors may lead to grossly incorrect conclusions. I am working with Denis Valle (University of Florida, School Forest Resources and Conservation), Tamer Kahveci (University of Florida, Department of Computer and Information Science) and Gordon Burleigh (University of Florida, Department of Biology) to develop new computational approaches that integrate multiple types of biodiversity data to better understand how ecological communities are altered by anthropogenic change. We are utilizing a variety of data sets including data on pitcher plant food webs, island bird communities, and tropical forest tree communities. This project is funded by the National Science Foundation- Advances in Biological Informatics.

Using intraspecific trait variation to understand processes structuring continental-scale biodiversity patterns.

Understanding variation in the internal and external drivers of community composition across taxa and systems informs both ecological theory and conservation, particularly regarding the resilience and composition of ecological communities in the face of rapid global change. For this project, my collaborators and I use National Ecological Observatory Network (NEON) data on intraspecific trait variation, collect additional measurements from NEON organismal samples, and compile additional data related to NEON sites and samples (e.g., phylogenetic community structure) to determine how assembly processes internal to the community (e.g., biotic interactions, microenvironmental heterogeneity) and large-scale assembly processes external to the community (e.g., climate, land use) combine to affect intraspecific trait variation and community structure at a continental scale. I collaborate with Phoebe Zarnetske (Michigan State University), Angela Strecker (Portland State University, Sydne Record (Bryn Mawr College), Lydia Beaudrot (University of Michigan), Yoni Belmaker (Tel Aviv University), and Mao-Ning Tuanmu (Yale) on this project which is funded by the National Science Foundation- Division of Environmental Biology.

 Intraspecific body mass within small mammal communities shows decreasing overlap at higher temperatures across NEON sites.

Pitcher Plant Food Webs

The northern pitcher plant, Sarracenia purpurea, is a carnivorous plant that inhabits nutrient-poor bogs from northern Florida up the east coast of North America and across Canada. The plant possesses tubular leaves that open during the growing season and fill with water. Upon opening, the leaves capture invertebrate prey that serves as the base of a complex food web containing bacteria, protozoa, and macroinvertebrates. The food web decomposes prey items captured by the plant, releasing essential nutrients to the plant. Due to its tractable nature and geographic range, the aquatic food web found in the leaves of the S. purpurea is a model system in community ecology. The continental distribution of the Sarracenia system provides the opportunity to explore the network structure and functioning of food webs from the local to the continental scale. In addition to field observations and experiments, I culture pitcher plant species and reassemble food webs in greenhouse experiments to study how food web structure effects population dynamics, decomposition, and species invasions.

DNA barcoding of plant-herbivore food webs in the sandhill ecosystem to quantify fire driven changes in feeding interactions

The longleaf pine ecosystem of the southeastern United States is one of the most threatened ecosystems in North America.  Management efforts have traditionally focused on longleaf pine regeneration, understory plants, and federally endangered species. However, conservation and restoration of the longleaf pine ecosystem requires the conservation and restoration of ecological interactions between species. Food webs, which depict feeding interactions as links between species, offer the type of innovative and forward-looking ecosystem level approach necessary to manage ecosystems. We explore plant-herbivore food web interactions by sampling plants and their insect herbivores on longleaf pine sandhill plots at with different fire frequencies at the at Ordway-Swisher Biological Station. In collaboration with Dr. Jiri Hulcr (UF, School of Forest Resources and Conservation), Pam Soltis (UF, Biology), Jaret Daniels (UF, McGuire Center for Lepidoptera & Biodiversity), we utilize metabarcoding of herbivore gut contents to characterize herbivore diets, and analyze how feeding interactions change with fire frequency. This project is currently funded by the UF/IFAS Dean of Research office.