Fig. 2.

Evolutionary dynamics of mutualisms when $k$ is small, and population 1 evolves slower than population 2 owing to (A) a longer generation time, (B) a lower mutation rate, (C) weaker selection, and (D) a smaller population size. Population parameters are the same as in Fig. 1, and $k=1/2$. A short-run Red Queen effect is observed for generation time, selection strength (especially), and population size. Relative differences in mutation rate again have no discernible short-run effect. In the long run, differences in mutation rate and generation time again have no effect, whereas a Red King effect is found for selection strength and population size.