Figure 4.

Relative effective size of populations with worker-produced males to that without male production by workers (ϕ=0), when laying workers produce variable numbers of males. r, breeding sex ratio (N_m/N_f); μ_wm2, average number of male progeny per laying worker; Poisson, male progeny number per laying worker distributes with the coefficient of variation expected under a Poisson distribution; 2 × Poisson, male progeny number per laying worker distributes with the coefficient of variation twice that expected under a Poisson distribution. Results for r=1, 5 and 10 are shown in panels a, b and c, respectively.