There has never been a better time for dinosaur fans. New species are named almost weekly, and refined techniques are telling us more about dinosaur lives than was ever possible before. The flood of information is so sweeping that it can be difficult for even specialists to keep up, particularly as the study of dinosaurs encompasses a variety of subdisciplines regarding disparate aspects of prehistoric biology, evolution, and extinction. Thankfully, a recent glut of dinosaur guides have recently cropped up to help dinosaur aficionados navigate the latest assemblage of facts and questions about Apatosaurus and company. The heftiest so far – both in terms of scholarly contributions and sheer physical weight – is The Complete Dinosaur, Second Edition.
The original edition of The Complete Dinosaur was issued in 1997. Even then, it was clear that an update would be inevitable – the 1990s saw an explosion of new ideas and techniques in the study of dinosaurs. Rather than throw out the original material, however, editors Michael Brett-Surman, Thomas Holtz, and James Farlow cut a few sections, appended updates to previous chapters, and accumulated new contributions. The massive book runs 1112 pages divided into 45 chapters, boasting profiles of major dinosaur groups, details about dinosaur biology, and useful summary chapters on subjects such as Mesozoic plants and fieldwork basics. A few angles, such exciting new research into what colors feathered dinosaurs were, didn’t make the cut, but the volume still covers a great deal of historical background, theory, and our present understanding of dinosaur biology.
Each chapter could merit a review by itself. The style and quality of each contribution varies from one chapter to the next.
At times, it’s difficult to know who The Complete Dinosaur is intended for. Whereas Ralph Molnar’s chapter on paleobiogeography is a well-written, accessible review that will undoubtedly be helpful to those who haven’t considered the importance of shifting landscapes to evolution, the position paper by John Ruben and coauthors on dinosaur physiology is a highly technical argument stemming from an insider dispute between workers such as Ruben, who stubbornly deny birds are dinosaurs, and the overwhelming majority of dinosaur experts. An atlas on dinosaur musculature by David Dilkes and coauthors hits a comfortable semitechnical tone and can act as a primer for students unfamiliar with rigorously reconstructing dinosaur soft tissues, while Emily Buchholtz’s summary of dinosaur brains shades slightly too technical to be accessible to anyone who doesn’t already have some background in neuroscience. Darren Naish adds a comprehensive, handy review of birds – essential for any dinosaur book that wants to call itself complete – but the section on molecular traces of dinosaurs by Mary Schweitzer and Mark Marshall is frustratingly lacking, only containing the briefest mention of Schweitzer’s work on preserved soft tissue remnants in Tyrannosaurus and Brachylophosaurus. The Complete Dinosaur is a mixed bag of dinosaur summaries.
Perhaps the uneven nature of such multi-expert anthologies is simply in the nature of the beast. Readers who want basic information about how dinosaurs are discovered and what kinds of dinosaurs once existed will find much to chew on. The tome also collects useful review chapters on dinosaur biology for students, amateur experts, and professional paleontologists. Even though some sections are swamped by technical language and debates are not always given a clear introduction, such as a trio of chapters on the ongoing argument over dinosaur physiology, The Complete Dinosaur is still a highly valuable resource for anyone with a serious interest in dinosaurs. Even as dinosaur family trees change, and discoveries alter what we thought we knew, the new volume is a fertile starting place for students and experts interested in paleontological problems they have not considered before. At the very least, The Complete Dinosaur demonstrates how exceptionally rich the study of dinosaurs has become.
Of all the contributions to the anthology, though, the last is the most thought-provoking. In “Dinosaurs and Evolutionary Theory”, Kevin Padian and Elisabeth Burton document how dinosaurs have often been sidelined in the development of evolutionary theories.
As Padian and Burton point out, Charles Darwin paid almost no attention to dinosaurs. Aside from Victorian science politics, perhaps that’s because dinosaurs were so strange that there was no reasonable way to turn them into evolutionary icons. (In general, Darwin eschewed identifying particular fossils as transitional forms.) Likewise, the role paleontology played in the early 20th century Modern Synthesis primarily focused on the better-sampled mammal fossil record, and even during the Paleobiological Revolution of the 1970s and 80s, invertebrate and mammal fossils formed the basis of new evolutionary theories. Dinosaurs were not part of the club. If there was any time that dinosaurs were used as evolutionary examples, it was when non-Darwinian mechanisms of orthogenesis, aristogenesis, and similar mechanisms were popular during the gap between Darwin and the Modern Synthesis. Dinosaurs were often trotted out as prime examples of irreversible evolutionary trends that caused lineages to become too big or too spiky to survive.
Perhaps it’s time to not just apply evolutionary theory to dinosaurs, but interrogate their record for new insights into how evolution works. The dinosaurian lineage, still going strong in avian form, has been around for over 245 million years, and reacted to drastic changes in climate and geography. If we can ask the right questions, and continue to fill in our understanding of prehistoric life, dinosaurs can serve as evolutionary models to gain new insights into evolution.
After all, Padian and Burton note, biologists regularly derive evolutionary hypotheses and assemble theories based upon living species that may not actually be representative of life as a whole. “The iconic organisms of evolutionary textbooks – fruit flies, flour beetles, Caribbean lizards, stickleback fishes, Galapagos finches – all have their evolutionary stories to tell, but in any of them do we find real generalizations about evolutionary theory? Or is it more accurate to say that they embody certain kinds of evolutionary processes and phenomena as good examples of the expectations of theory?”, Padian and Burton ask.
If we can carefully devise proper questions, then dinosaurs may be as informative about certain evolutionary questions as Anolis and Drosophila. That is the challenge that The Complete Dinosaur leaves its audience. The tome invites readers to sample and survey what we currently know about dinosaurs, and think of new directions to investigate these fantastic animals and what they can tell us about the history of life on Earth.