Instability in the FitzHugh-Nagumo model of reaction-diffusion, generating a labyrinth pattern from a line. Parameters: a0 = -0.1, a1 = 2.0, epsilon = 0.05, delta = 4.0, k1 = 1.0, k2 = 0.0, k3 = 1.0. Generated using the open source program: http://code.google.com/p/reaction-dif...