Figure 1

Impact of induced phenotypic switching on the cyclic phenotype frequency dynamics. (A): Coevolutionary dynamics between antagonistic phenotypes are predicted to continue indefinitely when no induced switching occurs due to time-lagged, negative frequency dependent selection (α _X = 0). (B): When induced switching occurs (here in only in species X, thus α _Y = 0) at a low rate ($0<{\alpha }_X<{\alpha }_X^{\ast }$), allele frequency cycles persist in time but at an altered amplitude and speed. (C): When the switching rate exceeds a threshold value ${\alpha }_X^{\ast }$, cycles begin to dampen and reach a stable equilibrium. (D-E): Increased levels of induced switching also decrease the amplitude and increase the speed of the cycles. Note that ${\alpha }_X^{\ast }$ in panels A-C and the one in panels D-F is different because of different selection coefficients used; the relation between the strength of selection and the persistence of cycles is examined in detail in the subsequent figure. The following parameter values were used: (A-C) s _X = s _Y = 0.3, (D-E) s _X = s _Y = 0.65; (A) α _X = 0, (B) α _X = 0.03, (C) α _X = 0.1; In all panels we used α _Y = 0. Period is defined as a number of generations during which the phenotype frequency cycles around to its original value.