Nonlinear Dynamics from Physics to Biology

S elf-organization has been a hot topic in the second half of last century whenphysicists and chemists discovered a variety of nonequilibrium phenomena thatcould be subsumed under a common heading. Self-organizing systems form or-dered states in space and time spontaneously and without an external template. The patterns are characterized as dissipative structures because their maintenance requires a flow of energy or matter. After introducing a flow of increasing strength into a system at equilibrium, patterns form instanta-neously at certain critical values of the flux. In the language of dynamical systems the-ory the patterns emerge at bifurcation points corresponding to some critical in-tensity of the flow. At present we know many well-studied examples of self-orga-nizing systems at many time scales and largely different spatial extensions. Exam-ples are the gigantic red spot on Jupiter, cloud patterns in the atmosphere, the Bénard phenomenon in the coffee cup, the Taylor-Cuvette flow, the Belusov-Zhabotinskii re