Fig. 6.

Time evolution of the Hawk frequency and population size for the payoff-based and dynamics-based models for the parameters: $W=15$, $d=0.85$, $\mathrm{\Psi }=0.4$. As in Fig. 5, the frequency trajectories are similar but the predicted population sizes differ dramatically. The payoff-based model predicts a positive population size at the upper intersection. For the dynamics-based approach, the intersection describing the Hawk invasion barrier is in the region of extinction, since the stable population size is negative