The Princeton Field Guide to Predatory Dinosaurs

Independent palaeontologist and palaeoartist Gregory S. Paul is well-known for his scientifically informed diagrams of dinosaur skeletons. After three editions of The Princeton Field Guide to Dinosaurs and two companion volumes on pterosaurs and extinct marine reptiles, I was ready to congratulate him on a job well done. He has collated arguably the largest collection of skeletal reconstructions of extinct Mesozoic reptiles in print. Imagine my surprise, then, when Princeton published this book only six months after the latest dinosaur guide. Does that mean that the dinosaur guide is not as complete as claimed? Have there been that many developments that a separate book is already warranted? I am confused by this book: time for an in-depth comparison.

In this review, I will only briefly describe the book's contents and assume that you are already familiar with Paul's earlier guides. Do please check out any of my previous reviews if you are new to this, otherwise, you know what to expect. Here, I will focus on comparing it to his original Predatory Dinosaurs of the World and the just-published third edition of The Princeton Field Guide to Dinosaurs.

To recap: as before, this book consists of two parts. The introduction contains the usual extended primer on all aspects of, here, predatory dinosaur biology, complemented by relevant background information on various aspects of the world they lived in. The field guide arranges taxa phylogenetically, relying as before on "a degree of personal choice and judgment" (p. 96), and provides the familiar telegram-style entries. For more complete species, Paul's signature diagrams of skulls or (partial) skeletons are given, together with the occasional life reconstruction. There is a refreshed selection of palaeoart throughout the book.

Some of you might remember Paul's first book with Simon & Schuster in 1988, Predatory Dinosaurs of the World (PDW). Remarkably, he does not mention what motivated him to write the current book or how it relates to PDW, acknowledging its existence only once. This first comparison is straightforward. A lot of the artwork and diagrams in PDW look familiar and were later reused or redrawn in much crisper detail. The field guide section contains many more technical details. Obviously, the number of known species has increased dramatically and there have been numerous changes to the taxonomical and biological details, so the book is a time capsule. However, do not get rid of your copy just yet! The narrative entries for each species contain historical information and technical details that would not be repeated in later books. Now, if all we had was PDW, I would have no hesitation in recommending The Princeton Field Guide to Predatory Dinosaurs as a long overdue and much-needed update. However, that is not the world we live in.

As I did for my review of The Princeton Field Guide to Dinosaurs (D3E), comparing it to the second edition (D2E), I did a similar page-by-page comparison between this book and D3E. Before we proceed, I want to emphasise that I have no qualms with any of the material itself: it is of the same high quality as found in D3E, but that is because most of it *is* found in D3E.

The introductory sections have been updated in numerous places, but some of these are rather inconsequential, omitting sections on ornithischians and sauropods and replacing references to "dinosaurs" with "dinopredators". In places, there are additional sentences or paragraphs, but some 90–95% of the text is identical. The only substantial additions are a 13-page section on hunting, scavenging, defence, and the occasional herbivory; and an expanded section on the evolution of flight that adds roughly a page of text. That section sees him double down on the idea that flight was secondarily lost numerous times. The selection of diagrams and illustrations has been updated, remixed, and refreshed in many places, though quite a few images are found in earlier books.

For the field guide section, the situation is much the same. Casually flicking through it, you would be forgiven for thinking this is literally D3E's theropods section, but that is not quite true. Although all the groups are discussed in the same order, after carefully comparing and cross-referencing with the index in D3E, I came up with the following tally: two species have been demoted, five have changed affiliation, seven have changed names, and twelve have been upgraded to separate entries: this is all housekeeping. More consequential are the 71 species not previously mentioned in D3E, though only nine are based on substantial remains or multiple skeletons; the other 62 are based on fragmentary or partial remains, meaning there is often "insufficient information" on anatomy. Whether these names will stand the test of time remains to be seen. Paul does not indicate whether they are new discoveries since the publication of D3E or whether he has used less stringent selection criteria. This leaves around 230 species that were already present in D3E. Although I did not systematically check all the details for each one, most appear identical.

The vast majority of the skeletal diagrams are the same. I counted three new skull restorations (new total 45), three new skeletal restorations (new total 110), and eight diagrams with added fore-and-aft views. Four other skeletal diagrams were taken from elsewhere in D3E. Additionally, there are nine new colour pieces, one additional shaded skull, and one additional muscle study.

Totting it all up, the outcome of this exercise is somewhat frustrating. There *is* new material in this book, but, given the amount of duplicated material, and seeing how substantial the update from D2E to D3E was, it is slim pickings, even for completists. To reiterate, it is not the material itself I take issue with, but how much of it was published just six months prior. Owners of D3E are justified in asking whether such a derivative book is a good use of their limited funds and shelf space, while others might just as well spend a little bit extra to get all dinosaurs between the covers of one book. These updates could, and should, have been included in D3E.

Unfortunately, as I was wrapping up this review, I noticed that Paul's website announces plans for separate field guides to sauropods and ornithischians as well. Given his formulaic approach so far, I fear that this would result in three books sharing very similar introductions between them while largely duplicating the field guide section of D3E. Such repackaging of material is not something I am in favour of, and, in my opinion, time and effort would be better spent working towards the fourth edition of the dinosaur guide.