Phase planes (A) and time series of the 2D system (3) (B) and the Gillespie model (C) for monostable, excitable and oscillatory behavior.

A: Phase plane representation for monostable (δa = 1), excitable (δa = 2) and oscillatory (δa = 3) behavior. The heatmap corresponds with the amount of times that the Gillespie simulation passes through a local region in phase space. The black trajectory corresponds with the simulation with Eq (3) and follows the path of highest probability obtained from the Gillespie data. Note that values corresponding with toxin levels equal to zero are not shown, due to the logarithmic scale. B: Time traces for the two-dimensional system (3), corresponding to the trajectory in the phase plane. C: Gillespie simulations. The toxin excitations have similar shape as when simulated with the deterministic models.