'Alex Rosenberg has written an extremely informative introduction to the issues in philosophy of biology. Offering a unified perspective on traditional problems of teleology, reductionism, the structure of evolutionary theory, and the nature of species, he provides lucid summaries of the competing approaches to these problems and develops interesting ideas and arguments of his own. The treatment throughout reflects current discussions among biologists and philosophers. This book ought to become the leading single-author text on the subject and it should be read by anybody who has an interest in the philosophy of biology.' Philip Kitcher, University of Minnesota, and Minnesota Center for the Philosophy of Science