Structural stability and evolution of urban systems

This paper proposes an evolutionary approach to urban system theory, which aims to explain the specific spatial configuration of an economy observed today as an outcome of the historical evolutionary process. To illustrate the approach, we consider a simple model of an urban system, and demonstrate that as the population of the economy increases gradually, new cities are created periodically as the result of the catastrophic bifurcation of the existing system, and that as the number of cities increases, the urban system will approach a highly regular central place system. (C) 1997 Elsevier Science B.V.