Climate and Mammalian EvolutionA review of After the Dinosaurs: The Age of Mammals. By Donald R Prothero. Bloomington (Indiana): Indiana University Press. $39.95. xvi + 362 p + 10 pl; ill.; index. ISBN: 0‐253‐34733‐5. 2006.

Abstract

A review of After the Dinosaurs: The Age of Mammals. By Donald R Prothero. Bloomington (Indiana): Indiana University Press. $39.95. xvi 362 p 10 pl; ill.; index. ISBN: 0-253-34733-5. 2006. This book is a tour of the evolution of mammals over the Cenozoic Era (the past 65 million years since the extinction of the dinosaurs) against the backdrop of the Earth’s changing climate. Written for nonspecialists, but useful for paleontologists or evolutionary biologists, After the Dinosaurs joins similar volumes in the Life of the Past series edited by dinosaur paleontologist James O Farlow for Indiana University Press. As series editor, Farlow has helped to bring all sorts of syntheses on a variety of paleontological topics that are up to date and mostly accessible to general readers. Although most of these titles concern the dinosaurs, others (such as After the Dinosaurs) explore other vertebrate groups over different times in Earth’s history. In comparison with dinosaurs, Cenozoic mammals offer a more complete fossil record, more recent diversification, better understood functional anatomy, and arguably a more mature understanding of taxonomy and phylogenetic relationships. All of these factors should make it possible to develop a more complete and meaningful synthesis of mammalian history than dinosaur history. In his preface, the author makes clear his goal of summarizing Cenozoic mammal succession against global trends in climate. Along the way, he acknowledges a small number of other grand syntheses on Cenozoic mammals by Osborn, Kurten, Pomerol and, more recently, Agusti and Anton for Europe, which Prothero frequently cites. In this way, he informs readers of the ancestral lineage of After the Dinosaurs. Next follows a brief, obligatory introduction to the topics of field paleontology, geologic time, and systematics and taxonomy ( just enough to understand the rules of giving names to species and higher taxa, but not enough to understand phylogenetic relationships; see below). The rest of the volume follows a chronological organization, with each epoch of the Cenozoic (Paleocene and Eocene, among others) treated as a separate chapter. To begin, let us establish what After the Dinosaurs is not. This book is not a comprehensive account of the entire fossil record of mammals, which span the past 225 million years. Beginning 65 million years ago at the K/P boundary (“K/P” is replacing “K/T” as geologists abandon the “Tertiary Period” in favor of the “Paleogene” and “Neogene”), readers are placed in the final third of mammalian history or the final fifth of synapsid history. Synapsida is the larger group to which mammals belong, consisting of mammals and the mammal-like “reptiles”—pelycosaurs and therapsids—that are more closely related to mammals than to other living vertebrates.