The fascinating patterns on the shells of tropical sea snails are not only compellingly beautiful but also tell a tale of biological development. The decorative patterns are records of their own genesis, which follows laws such as those of dune formation or the spread of a flu epidemic. Hans Meinhardt has analyzed the dynamical processes that form these patterns and has retraced them in computer simulations. His book is exciting not only for the astonishing scientific knowledge it reveals but also for its fascinating pictures. An accompanying CD-ROM with the corresponding algorithms allows the reader to simulate the natural pattern formation and growth processes.