Figure B.1: There is close correspondence between the stability analysis and the numeric simulations from the main text. There are two stable monomorphic equilibria which occur over the ranges shown in A. In one of these equilibria the $B_2$ is fixed and the cultural trait is fixed in females, but absent in males. This corresponds to the results of the numeric simulation as shown in B and C. In the other equilibrium, the $B_1$ allele and cultural trait are fixed in both sexes. This also corresponds to the results of the numeric simulations as shown in D and E.