Abstract: Physical or biological systems governed by nonlinear differential equations can exhibit very complicated behavior. In this talk we will consider an ecological system consisting of worms and birds who prey on them. This system is described by a single ODE. The system exhibits interesting behavior, in particular, it undergoes a bifurcation, i.e., a dramatic change of behavior of the solutions of the system for a small change of the parameters of the system. It has another unexpected property – for some intervals of values of the parameters it has not only one but two stable equilibria (this is called bistability). Most amazingly, we will analyze the behavior of the system without ever solving a single differential equation! No background in differential equations or biology is needed to understand this talk.