The Role of Urbanization and Community Assembly on the Microbial Defense Mechanisms of Plethodon cinereus

Elle Mae Barnes, Fordham University


The current global mass extinction of amphibians, driven by both habitat degradation and wildlife disease (Batrachochytrium dendrobatidis, Bd), has resulted in the extinction of nearly 100 species and threatened approximately 40% of the remaining 7000 species. Habitat degradation, of which the most extreme form is urbanization, which involves increasing levels of impervious surfaces, man-made structures, and human populations, can shift soil characteristics altering microbial composition. Such environmental changes ultimately shift taxonomic and functional diversity of bacterial species. Given that the amphibian cutaneous microbiome is supplied with microbial colonists from the soil community, host health and disease protection can be compromised with changes in the soil environment. For the bacteria that successfully colonize amphibian skin, their dominance in the community will be further regulated by intra- and interspecific interactions on the host as they compete for resources and exchange antibiotic metabolites. This dissertation combines ecological theory and applied molecular biology to elucidate the mechanisms behind variation in microbiome composition, structure, and function. Further it explores the factors most important for guiding assembly of the amphibian microbiome and how variation in these processes might affect disease resistance. Overall, this research provides essential insights into the ecological dynamics of host-associated microbiomes, the use of probiotics in wildlife disease management, as well as the processes driving variation in community structure and diversity over space and time.

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Recommended Citation

Barnes, Elle Mae, "The Role of Urbanization and Community Assembly on the Microbial Defense Mechanisms of Plethodon cinereus" (2020). ETD Collection for Fordham University. AAI27964268.