Figure 2.

Dynamics of allele frequencies in a two-deme model with unequal parameter values between demes. The positions of the calculated equilibria are shown for single populations with no migration (red and blue rectangle for deme 1 and 2; for simplicity, c = 1). a) Different costs of disease, no migration (u1 = u2 = 0.05, b1 = b2 = 0.05, s1 = 0.1, s2 = 0.3, m = 0): unstable dynamics, as the graph of (R,a) spirals outwards with different frequencies in each deme. b) Different costs of disease, with migration (u1 = u2 = 0.05, b1 = b2 = 0.05, s1 = 0.1, s2 = 0.3, m = 0.03): stable dynamics, with synchronised oscillations in the two demes spiralling inwards towards the interior equilibrium points. c) Fitness costs of RES and avr in one deme but not the other (b2 = u2 = 0.05, b1 = u1 = 0, s1 = s2 = 0.1, m = 0.03): synchronised, stabilising oscillations. d) No cost of RES in one deme, no cost of avr in the other (b1 = u2 = 0, b2 = u1 = 0.05, s1 = s2 = 0.1, m = 0.03): synchronised, stabilising oscillations. e) Identical costs of resistance and virulence but different costs of disease (b1 = b2 = 0.05, u1 = u2 = 0.05, s1 = 0.1, s2 = 0.2), initial allele frequencies are (R, a) = (0.05, 0.7) in deme 1 and (0.1, 0.01) in deme 2: unstable dynamics occurs if migration m = 0.2. f) Identical parameters as in (e), initial allele frequencies are (0.05, 0.7) in deme 1 and (0.1, 0.01) in deme 2: stable dynamics occurs if migration m = 0.03.

Tellier and Brown BMC Evolutionary Biology 2011 11:319   doi:10.1186/1471-2148-11-319
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