The demise of the dinosaurs some 66.4 million years ago (MYA) has come to embody for scientist and layman alike the concept of extinction, especially that of mass extinction. So pervasive has this idea become that no book, whether specializing on dinosaurs or representing a general overview of biology or geology, concludes without dealing with dinosaur extinction. In the context of the Phanerozoic history of life, this preoccupation with dinosaur extinction is probably not warranted because it may tell us little about extinction or evolutionary processes in general.