Erin Shappell
BioE Ph.D. Defense Presentation
Date: Friday, November 13th, 2026
Time: 9:00 AM
Location: EBB 3029
Virtual Meeting Link: https://gatech.zoom.us/j/97741543446

Advisor: Dr. Hang Lu (School of Chemical and Biomolecular Engineering)

Committee Members:
Dr. Patrick McGrath (School of Biological Sciences)
Dr. Gordon Berman (Department of Biology, Emory University)
Dr. Simon Sponberg (School of Physics)
Dr. Eva Dyer (School of Engineering and Applied Science, University of Pennsylvania)

To eat or not to eat: A Computational Framework for Modeling Feeding and Exploratory Behavior in Aging C. elegans
To eat, or not to eat? This seemingly simple question reflects the complex coordination of sensory, motor, and physiological processes that allow organisms to locate and consume food. Understanding how feeding-related behaviors change with food conditions and age requires methods capable of capturing subtle movements and their organization over time. In this work, I develop computational approaches for quantifying feeding and exploratory behaviors in freely moving Caenorhabditis elegans and investigate how feeding history, sensory information, and aging influence these behaviors.
First, I introduce EZ-FRCNN and PumpKin, which enable automated detection of biological structures and measurement of pharyngeal pumping without immobilization or genetic modification. Next, I present CastKin, a method for isolating exploratory head movements from broader body motion. Using these tools, I demonstrate that feeding-related behaviors vary with feeding history and pumping ability, while both olfactory and mechanosensory cues independently influence head casting.
Finally, I develop a head-centered Markov model of foraging behavior and apply it to over 1,400 videos of well-fed and starved worms across the first 14 days of adulthood. This analysis reveals previously unresolved behavioral subtypes and age- and feeding-dependent differences in how worms occupy and transition between behavioral states.
Together, these findings demonstrate the value of measuring fine-scale behaviors and their temporal dynamics, providing new tools and insights for understanding how feeding and exploration are regulated throughout adulthood.