Dinosaurs: How They Lived and Evolved

More than 1,000 dinosaur species have been named, so describing for laypersons the attributes of this large and complex group of animals is a daunting task, but paleontologists Naish and Barrett largely succeed in this extensively illustrated volume. They provide ample background material demonstrating some of the techniques scientists use to gain a deeper understanding of the evolutionary relationships, anatomy, physiology, behavior, and community ecology of extinct animals. The authors regularly explain how the views of scientists have changed in the face of a constantly growing set of fossils and new methods of analysis. For example, they assert that what had previously been described as a miniature version of Tyrannosaurus rex, a dwarf dinosaur called Nanotyrannus, is actually a juvenile T. rex. Similarly, they reassess the origin of flight in birds as well as the shape of the fleshy parts of many dinosaur faces, concluding that the “standard” interpretations might not be correct. The book’s least successful aspect is the overly detailed and technical chapter on dinosaur cladistics, in which the authors attempt to build a full family tree of all of the subgroups of dinosaurs. Otherwise, Naish and Barrett provide an interesting perspective on the current state of dinosaur knowledge. Illus. (Oct.)