ny authors including Ellison (1993), Nalcamaru et al (1997), Ohtsuki et al (2006) and Ohtsuki & Nowak (2006a). The following result can be found in Ohtsuki Sc Nowak (2006a) and holds for weak selection. For DB updating and low mutation Cu —) 0) we have 3N — 8 a— (2.23) Note that a is an increasing function