Catastrophes Promote Cooperation: Experimental Approach with Catastrophe Game

As seen in the Great East Japan Earthquake, people constantly face “abrupt changes�? of which occurrence they cannot surely foresee. In this study, such “sudden changes�? was defined as “catastrophes.�? Building on this idea, the aim of this study is to indicate the evolution of cooperation is also promoted by catastrophes, as well as punishments, inspired by the evolution by biological catastrophes. The present study investigated whether: (a) the prior “Notice of Catastrophes�? promotes cooperation or not and (b) the “Occurrence of Catastrophes�? did. Therefore, the Total Catastrophe Game is examined based on a repeated public goods game with stranger matching and anonymous conditions, where changes occur on the player’s endowments. The results showed that although the notice of catastrophes was not found to have a significant effect, cooperation was promoted due to the occurrence of catastrophes. Furthermore, a correlation between the magnitude of the occurring loss and the contribution level was found. The results suggested that not only punishments, but also catastrophes promote cooperation as an emergency urge. Furthermore, cooperation is promoted not as strategic but as altruistic behavior.