Figure 1.

Conflict and Fisher's sons effect under different genetic mechanisms. Conflict concerns a mutant male with a rare gene that confers a male mating advantage, but has a harmful effect on the female that he mates with (see text) that affects only their joint progeny (p=0; see text). The mating advantage is advantageous to males if B lies above the lower curve. The three upper curves are the thresholds for B above which it will pay the female to mate with males with the trait (at lower B, it pays the female to resist). Conflict occurs when B lies between the male and female thresholds. The dominant autosomal case (A) is taken from Parker (1979). The sex linkage (Y, X and Z-linked) cases are plotted from the equations in Andrés & Morrow (2003) with p=0, after correcting a typographical error in their equations (10.1) and (10.2).