(6.6) that strategy p is favored by selection, in the limit of low mutation becomes 1 Lp = — — b — c + d)(p + + 2(b — d)] dg = p2(a — b — c+ d)+2p(b — d)— al (a +2b — c — 2d) > 0 For p = (0,1), which is the pure strategy B, we obtain: (6.16) a+2b<c+2d (6.17) This condition is equivalent to PA