How Species Arise
Charles Darwin was so convinced that species arose as an outcome of adaptation driven by natural selection that he did not consider alternatives. He also gave surprisingly little attention to species formation, apparently considering it to be an inevitable consequence of natural selection operating on diverse organisms in a heterogeneous world. The 1930s and 1940s saw the publication of two books focused on species: Theodosius Dobzhansky's Genetics and the Origin of Species, and Ernst Mayr's Systematics and the Origin of Species. Jerry Coyne and Allen Orr's new book, Speciation, is clearly inspired by Dobzhansky's. Coyne and Orr largely ignore the work of those who actually identify, delimit and describe species. Nevertheless, their book, which offers a critical analysis of the enormous literature dealing with speciation, is an impressive achievement of great depth and broad scope. It will be required reading for those studying species and species formation.