Fig. 4.

Using a continuous game theory model and our empirical estimates of female RRS, we demonstrate that only a single life history variant (age 3 spawners) can evolve (A), and that only a single ESS exists (age 3 spawners) when the resource niche is narrower than the competitive niche (B). (The mathematical meaning of resource and competitive niche width are defined in the SI Appendix and shown graphically in SI Appendix, Fig. S9.) An individual-based model independently illustrates that only age 3 spawners can exist if there is no negative frequency dependent selection, even if all four life history strategies are initially present within the population (C). When we widen the resource niche, four life history variants evolve in the game theory model (D), resulting in four ESSs coexisting because NFD, as illustrated on a fitness landscape (E). The individual-based model also independently illustrates that coexistence of the four different age-at-spawning strategies occurs when parameterized with our estimates of NFD (F).