Graduation Semester and Year
Spring 2024
Language
English
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Biology
Department
Biology
First Advisor
Dr. Matthew Walsh
Second Advisor
Dr. Scott Coleman
Third Advisor
Dr. Jeff Demuth
Fourth Advisor
Dr. Luke Frishkoff
Fifth Advisor
Dr. Alison Ravenscraft
Abstract
Evolutionary theory proposes that increases in brain size confer cognitive and behavioral benefits that offset the expensive investment in brain tissue. However, few studies have examined the relationship between brain size, cognition, and behavior within species. The majority of research has focused on cross-species comparisons, thus there is a need for empirical research within species examining how contrasting ecological pressures select for cognitive and behavioral benefits and how these may evolve in tandem with changes in brain size. My dissertation addresses this gap by examining: 1) Whether selection on brain size is linked to improvements in cognitive ability; 2) How changes in natural selection influences shifts in brain size and behavior in a natural setting; and 3) How different selective forces shape behavioral plasticity in a model system of Trinidadian killifish (Anablepsoides hartii). In my first chapter, I demonstrate that killifish in absence of predators have evolved improved learning and reversal learning in a food reward maze task and examine connections to brain size to determine how evolved brain size influences learning ability. In chapter two, I examine how a change in selection from environments dominated by predation to competition selects for increased aggressive behavior by examining aggression levels in second generation lab reared killifish. I additionally examine how increased brain size influences aggressive behavior and growth in fish originating from high predation locales that have been transplanted into a site without predators. Finally, in chapter three, I test for predator-mediated behavioral plasticity in second generation lab reared fish and wild-caught fish to examine the interplay between genetic background and environmental cues on shifts in behavior.
Keywords
Aggression, Behavior, Brain size, Cognition, Competition, Ecological drivers, Evolution, Learning, Natural selection, Predation
Disciplines
Behavior and Ethology | Ecology and Evolutionary Biology | Evolution | Population Biology
License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Korte, Meghan, "Exploring ecological drivers of evolution of the brain, cognition, and behavior" (2024). Biology Dissertations. 3.
https://mavmatrix.uta.edu/biology_dissertations/3