Interesting: In the "change the payoffs" version, if you set the cooperate/cooperate to +2 (or +1) and change the cheat/cheat punishment to -3 or -4 or higher,

Interesting: In the "change the payoffs" version, if you set the cooperate/cooperate to +2 (or +1) and change the cheat/cheat punishment to -3 or -4 or higher, you get a situation that alternates between a greater or lesser number of cheaters and cooperators. The copycats get eaten instantly.