Environmental feedback allows escape from the prisoner's dilemma
department or school: Science, Faculty of
department or school: Mathematics, Department of
data provider: DSpace
degree campus: UBCV
creator: Sudweeks, Jaye
issued: 2022-12-20T23:56:32Z
issued: 2022
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: The prevalence of cooperative behavior is a fundamental problem in evolutionary biology. Because cooperative behaviors impose a cost, cooperative individuals are vulnerable to exploitation by Defectors that do not contribute and instead benefit from the cooperation of others. The bacteriophage ϕ6 shows strategies of cooperation and defection during infection. While replicating inside a host cell, ϕ6 viruses produce essential proteins in the host cell cytoplasm. Because coinfection is possible, a virus does not have exclusive access to its own products. Cooperators viruses produce products while Defector viruses produce less and instead steal from Cooperators. Previous work found that ϕ6 is trapped in the prisoner’s dilemma, predicting that Defectors will replicate faster than Cooperators and out-compete them; cooperation is doomed. Still, cooperative ϕ6 exist, so there must be a mechanism that maintains cooperation. Defectors are advantaged when coinfection is common and there is ample opportunity to extort Cooperators. However, this advantage wanes when coinfection is less common, and Cooperators are advantaged when single infection is common. The rates of single infection and coinfection are modulated by the densities of hosts and viruses. We propose that environmental feedback, or the interplay between viral and host densities, might maintain cooperation in ϕ6 populations. We develop and analyze a mathematical model that incorporates environmental feedback and find that for many parameter combinations, environmental feedback leads to the co-existence of Cooperators and Defectors.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/83447
note: ENVIRONMENTAL FEEDBACK ALLOWS ESCAPE FROM THE PRISONER’S DILEMMAbyJAYE SUDWEEKSBS, North Carolina State University, 2019A THESIS SUBMITTED IN PARTIAL FULFILLMENT OFTHE REQUIREMENTS FOR THE DEGREE OFMASTER OF SCIENCEinTHE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES(Mathematics)THE UNIVERSITY OF BRITISH COLUMBIA(Vancouver)December 2022©Jaye Sudweeks, 2022The following individuals certify that they have read, and recommend to the Faculty of Graduateand Postdoctoral Studies for acceptance, the thesis entitled:Environmental feedback allows escape from the prisoner’s dilemmasubmitted by Jaye Sudweeks in partial fulfillment of the requirements for the degree of Masterof Science in Mathematics.Examining Committee:Christoph Hauert, Professor, Mathematics, University of British ColumbiaSupervisorAlun Lloyd, Professor, Mathematics, North Carolina State UniversitySupervisory Committee MemberLaura Parfrey, Professor, Zoology, University of British ColumbiaSupervisory Committee MemberiiAbstractThe prevalence of cooperative behavior is a fundamental problem in evolutionary biology. Be-cause cooperative behaviors impose a cost, cooperative individuals are vulnerable to exploitationby Defectors that do not contribute and instead benefit from the cooperation of others. The bacte-riophage ϕ6 shows strategies of cooperation and defection during infection. While replicating insidea host cell, ϕ6 viruses produce essential proteins in the host cell cytoplasm. Because coinfection ispossible, a virus does not have exclusive access to its own products. Cooperators viruses produceproducts while Defector viruses produce less and instead steal from Cooperators. Previous workfound that ϕ6 is trapped in the prisoner’s dilemma, predicting that Defectors will replicate fasterthan Cooperators and out-compete them; cooperation is doomed. Still, cooperative ϕ6 exist, sothere must be a mechanism that maintains cooperation. Defectors are advantaged when coinfectionis common and there is ample opportuni…
has type: Thesis/Dissertation
date issued: 2023-05
is shown at: 10.14288/1.0422760
language: eng
degree discipline: Mathematics
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Hauert, Christoph
type: Text
identifier URI: http://hdl.handle.net/2429/83447