Honors Theses

Date of Award

Spring 4-22-2021

Document Type

Undergraduate Thesis



First Advisor

Peter C. Zee

Second Advisor

Thomas A. Werfel

Third Advisor

Colin R. Jackson

Relational Format



The purpose of this study was to understand the predator-prey relationship between C. elegans worms and P. fluorescens bacteria in liquid media. We were aiming to create a predation model of the relationship between these two species.

This study was performed through three experiments. Using 96-well plates, we were able to measure the change in optical density (OD) of these wells and calculate the growth rate. This growth rate was then graphed and analyzed. The first experiment contained P. fluorescens and KB liquid media, this study demonstrated that the bacterial population has a carrying capacity. We were also able to use this study as a baseline metric of bacterial growth in this environment. The second experiment measured the growth of P. fluorescens in the presence of a predator, C. elegans. Varying initial densities of P. fluorescens were grown in wells with a standard amount of C. elegans. The third and final experiment was similar, but instead had varying initial densities of C. elegans with standard P. fluorescens in each well.

Overall, we found that P. fluorescens had a carrying capacity in their wells, and that the presence of C. elegans effectively lowered the growth rate of the bacteria. Because of inconsistencies in C. elegans population density after the bleach synchronization process and contamination during the process, we were unable to parameterize the Lotka-Volterra predation model with this data. Further studies and troubleshooting would be required to finish this experiment.

Accessibility Status

Searchable text



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.