In this book, Kevin Padian, world-renowned expert on dinosaurs, takes a historical approach to evolution and gives his view of some of the key problems of the theory of evolution: Do species correspond to a specific type, or are they constantly undergoing transformation? In order to know a species, should the type be identified or should the transformation be explained? This debate, first opened by Linnaeus and relaunched today by Ernst Mayr and Stephen Jay Gould, gives Padian the opportunity to review Darwin’s writings on the classification of the species. It also allows him to rediscover Sir Richard Owen — the now nearly forgotten rival of the author of The Origin of Species — whose works represent a significant step in the history of biological thought. For Darwin, evolution was a slow, physical transformation of living creatures, based on natural variations which are gradually selected by the forces of nature. But for Owen, the Victorian anatomist and transcendalist, each species evolved through a series of essential forms — almost archetypes.

How are Darwin’s and Owen’s opposing views regarded today? Padian shows how the study of dinosaurs in recent years has tipped the scale — perhaps conclusively — towards a Darwinian transformist conception of evolution.

Kevin Padian, an expert in Mesozoic reptilian fossils, is a professor in the Department of Integrative Biology and Curator of Palaeontology at the University of California’s Museum of Palaeontology, at Berkeley.