Change Your Tags Fast! - A Necessary Condition for Cooperation?

Several tag models with intriguing properties have been advanced recently. But currently there is little detailed understanding of the underlying processes. Specifically it is not know what (if any) are the necessary conditions for tag systems to produce high levels of cooperation. We identify, for the first time, what appears to be a necessary condition that previous tag models implicitly contained. It appears that, in general, for tag-based systems to support high levels of cooperation tags must mutate faster than strategies because cooperative tag groups need to spread (by mutation of tags) before free riders (by mutation on strategies) invade the group. We test this theory with simulation.