Fig. 2

\(P_{Mut}\) (black lines), P ₁ (red lines), and P _con (blue lines) for resistant cost-free mutations. a Probabilities \(P_{1}\) and P _Mut increase with increasing uN ₀, for R _m  = 6 and m = 0.95 (solid lines) or R _m  = 12 and m = 0.98 (dotted lines). b All probabilities increase with increasing R _m , for m = 0.95 (solid lines) and \(m = 0.98\) (dotted lines), with uN ₀ = 1. Curves only extend as far as R _m  = 1/[2(1 − m)(1 − u)] (see Additional file 1: end of Section A1.1b) above which the strength of Y drive m < m _crit and population elimination does not occur. c Probabilities decrease with increasing \(m\) (strength of Y drive), for R _m  = 6, uN ₀ = 1. d Probabilities increase with increasing mutant fitness parameter w, for \(R_{m} = 6,m = 0.95\) (solid lines) and \(R_{m} = 12,m = 0.98\) (dotted lines), and \(uN_{0} = 1\). The deterministic model shows that the population will be eliminated for w ≤ 0.563 for m = 0.95, and for \(w \le 0.452\) for m = 0.98. For all plots, h ₀ = 0.05. Error bars at low \(R_{m} , w\) and high m show the standard error for simulations (averaged over \(10^{6}\) runs, N ₀ = 10⁶), when the branching process model does not apply; if not shown, error is within thickness of plot line