This book, based on a symposium of the Linnean Society, discusses the diversity of current evolutionary research. It approaches the subject from several different angles, bringing together eminent authors from a variety of disciplines. Contributors include Stephen J Gould, who discovers in the earlier work of Hugo de Vries parallels with his ideas on punctuational evolution; Guy Bush, who considers why there are so many small animals; and Peter Sheldon, who examines fossil trilobite sequences for evidence of microevolutionary processes and considers models of speciation.