research
What is the relationship between diversity and function in symbiotic microbial communities? From forests to seagrass beds, there is compelling evidence that biodiversity contributes positively to the functioning of these ecosystems. However, the importance of diversity to function is less clear for microbial symbiont communities, in which there is often a high degree of functional redundancy.
My post-doctoral research investigated links between the diversity and function of bacterial symbionts on amphibian skin. These bacteria are known to play a role in protecting their hosts from a deadly fungal pathogen, Batrachochytrium dendrobatidis (i.e., chytrid fungus), that is having devastating effects on many amphibian populations around the globe. This research, which is ongoing, aims to better understand what the critical diversity components are within the bacterial community as well as how the presence of chytrid impacts these diversity components. In addition to addressing a central question in ecology—that of the importance of diversity to function—this research may lead to novel insight into methods to successfully enhance the disease resistance function of symbiotic microbes.
My current research investigates the diverse microbial communities on the skin of amphibians. I have ongoing research projects in both temperate and tropical systems.
EXAMINING THE TAXONOMIC, GENETIC, AND FUNCTIONAL DIVERSITY OF THE AMPHIBIAN SKIN MICROBIOTA
ECOLOGICAL DRIVERS OF MICROBIOME DIVERSITY
How are microbial symbiont communities established and maintained? What ecological factors alter the diversity of these communities? Linkages between the species composition of their microbial symbiont communities and host health have been established for a variety of organisms, including humans. However, the processes governing community assembly and dynamics in microbial systems remain relatively unknown. Community assembly theory, including metacommunity theory, provides a framework for disentangling the relative contribution of various ecological processes to observed patterns of diversity. An understanding of these processes may lead to improved strategies for restoring or maintaining a host’s microbial symbionts, ensuring that they can provide critical functions.
I am investigating the processes and factors that structure the microbial communities living on amphibian skin, to better understand how and why it varies among individuals, among species, and across space and time. Coupled with our understanding of the disease-resistance function of these communities, this research may provide insight into the underlying causes of variation in intra- and interspecific susceptibility to disease and may inform efforts to increase resistance in susceptible individuals via the application of probiotics.
INTEGRATING SPECIES INTERACTIONS AND SPATIAL PROCESSES TO EXPLAIN INSECT DISTRIBUTION ON A PATCHY RESOURCE
What are the relative roles of different ecological processes in structuring the abundance and distribution of organisms? The vast majority of organisms occupy spatially structured habitats, subsisting in collections of individual localities interconnected by dispersal. Because habitat spatial structure can greatly affect population connectivity as well as interactions between species, it is important to understand how and why individual localities (i.e., fragments or patches) vary in species composition within a given region. Explaining this variation requires considering processes occurring at multiple, hierarchical spatial scales, including both regional and local scales. Studies of regional processes determine how species distributions are shaped by differential colonization of patches based on dispersal limitation and habitat selection. Studies of local processes focus on differential survival occurring after colonization―that is, how species’ abundances within patches are altered by abiotic conditions and biotic interactions.
My dissertation research investigated several regional and local processes to explain observed variation in abundance and distribution of several organisms associated with the egg masses of red-eyed treefrogs. Specifically, I asked 1) how do the spatial arrangement and quality of habitat patches in the environment influence patterns of colonization by different species, 2) how do interspecific interactions facilitate dispersal and colonization, and 3) how do patterns of abundance continue to change following colonization depending on biotic interactions and habitat condition?
My dissertation research focused on a different community of amphibian symbionts: the diverse organisms found in association with the arboreal egg masses of red-eyed treefrogs (Agalychnis callidryas)
Searching for amphibians on a brisk spring morning in the Northeastern US.