Figure 4

Associated Fokker-Planck solutions of the Gierer-Meinhardt system with two morphogens in two spatial dimensions. Cases correspond to (left) q = -2 and r = 4.5, (middle) q = 0 and r = 1, (right) q = 2 and r = 4.5. The Fokker-Planck equation was solved in Comsol, until steady state (total time T = 1000) with a time step of 0.01, and zero-flux boundary conditions. The initial condition was defined as $u\left(x,y,t=0\right)=e^{-\left(x^2+y^2\right)}$ over the domain x, y ∈ [-5, 5], and a diffusion coefficient D=0.04 was used for morphogen u (morphogen v has a diffusion coefficient equal to 1).