Date of Award


Degree Type


Degree Name

Master of Science


Applied Mathematics


Lindi Wahl

Second Advisor

Geoff Wild


The evolution of cooperation on networks is one approach to understanding how cooperation can evolve in social populations with local interactions. Much attention has been focused on heterogeneous networks, where individuals do not necessarily have neighbourhoods of the same size. We consider bipartite net-, works, a specific class of heterogeneous networks which consist of two disjoint classes of vertices, each with a different number of neighbours. Vertices in each class only have neighbours in the other class. Given this network structure, we develop evolutionary game dynamics based on the Prisoner’s Dilemma, a social dilemma game. Using pair approximation techniques on these bipartite networks, we examine the claim that network heterogeneity promotes cooperation. We find that for bipartite networks, this is not necessarily the case, and that the evolution of cooperation is impeded by increased heterogeneity.



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