Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Psychology
Program Name/Specialization
Cognitive Neuroscience
Faculty/School
Faculty of Science
First Advisor
Noam Miller
Advisor Role
Supervisor
Abstract
Animals form groups for a variety of reasons, primarily as a way to increase access to food, mates, and safety. An important attribute of these groups is their personality composition. Personality is defined as repeatable traits over time and context, and has been found across multiple taxa. Traits have been found to be heritable, and are thus a unit for natural selection to act upon. Having a heterogeneous group may be beneficial for survival in a changing environment. The question of how the personality composition of the group affects group behaviour has rarely been asked in the field of animal behaviour, especially across different species.
This question forms the central part of this dissertation. To attempt to answer it, I first present an agent-based model of cooperation in fruit fly larvae with differing personalities, which shows how individual and environmental effects interact to alter cooperation. I next present an experiment on two species of fish (zebrafish and guppies), in which I artificially created groups with specific personality compositions, and ran them through a battery of tasks, both alone and in groups. I found strong differences across species in how personality affected their collective behaviours. Finally, I asked how groups are formed, when individuals are allowed to form their own groups. Large groups of zebrafish were given 3 days to assort into groups in a large arena, and then I measured their personalities. I present evidence that personality affects how large groups can get, but that zebrafish do not seem to care who they form groups with. This work deepens our understanding of how personalities function in shaping the behaviours of groups, and adds a necessary comparative lens to understanding both the proximate and, indirectly, the ultimate reasons for why variation in personality persists.
Recommended Citation
Shoot, Tanya T., "The role of the individual in animal collectives" (2025). Theses and Dissertations (Comprehensive). 2706.
https://scholars.wlu.ca/etd/2706
Convocation Year
2025
Included in
Animal Studies Commons, Comparative Psychology Commons, Experimental Analysis of Behavior Commons, Personality and Social Contexts Commons