Punctuated Equilibrium or Evolution?: a Comparative Test of Two Models of Rivalry Development

Two prominent explanations have been offered to explain the development of enduring rivalry. The evolutionary model stipulates that enduring rivalries are largely indistinguishable from lesser competitions at their outset and develop over time, taking on more distinctive conflict patterns as the adversaries recognize their long-term competition and react accordingly. In contrast, the punctuated equilibrium model suggests that patterns in enduring rivalries are largely determined at the outset of the competitions by exogenous factors, with little systematic change in conflict patterns over the lifetime of the rivalry. This paper provides the first head-to-head test of competing propositions from these two models, focusing on the severity level of confrontations in potential rivalries. Eventual enduring rivalries do not appear to differ fundamentally from other types of adversaries early in their relationship, supporting the evolutionary model. While protorivalries tend to show increasing conflict severity over time, enduring rivalries do not, supporting the punctuated equilibrium model. Elements of each model help to account for changes in conflict severity, although neither model receives complete support. We conclude by discussing future research directions, emphasizing the elaboration and possible integration of these models.