been much interest in studying evolutionary games in spatial set- EFTA00748876 Chapter 2: Strategy selection in structured populations 10 tings (Nowak & May 1992, 1993, Ellison 1993, Herz 1994, Lindgren & Nordahl 1994, Ferriere Michod 1996, Killingback & Doebeli 1996, Nalcamaru et al 1997, 1998, Nalcamaru & Iwasa