Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Graduation

Summer 2011

Document Type


Degree Name

Master of Science (MS)


Department of Biology


Symbiosis is defined as two species living together. This association between organisms is present at all taxonomic levels making it a ubiquitious phenomenon in ecology and evolution. I studied symbiosis among three species: a mutualistic bacterium, a parasitic fungus and an amphibian host. The first goal of my research was to examine how the mutualistic bacteria of amphibians’ skin are acquired. I demonstrated that a cutaneous mutualistic bacterial species, Janthinobacterium lividum, was transmitted environmentally, via soil, to the skin of an amphibian species, Plethodon cinereus. These results indicate that amphibians’ mutualistic bacteria can be acquired from the environment. Based upon these results, I examined the use of soil bioaugmentation in amphibian disease prevention. I sought to determine if the environmental transmission of the mutualistic bacterial species J. lividum could mitigate parasite infection by the fungal pathogen Batrachochytrium dendrobatidis on the skin of an amphibian species, P. cinereus. Cutaneous infection by B. dendrobatidis in amphibians causes the disease chytridiomycosis, which has decimated amphibian populations and species worldwide. I found that the environmental transmission of J. lividum inhibited initial colonization by B. dendrobatidis on the skin of P. cinereus (p<0.05) five days post-infection. The use of bioaugmentation may be a feasible conservation strategy that could supplant treating amphibians individually and protect global amphibian biodiversity against declines driven by chytridiomycosis.

Included in

Biology Commons



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.