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Aspects of the History, Anatomy, Taxonomy and Palaeobiology of Sauropod Dinosaurs

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Aspects of the History, Anatomy, Taxonomy and Palaeobiology of Sauropod Dinosaurs MICHAEL P. TAYLOR SAUROPODS 1 Aspects of the history, anatomy, taxonomy and palaeobiology of sauropod dinosaurs Michael P. Taylor This thesis is submitted in partial fulfilment of the requirements for the award of the degree of Doctor of Philosophy of the University of Portsmouth Palaeobiology Research Group School of Earth and Environmental Sciences Burnaby Building, Burnaby Road University of Portsmouth Portsmouth, PO1 3QL Hampshire ENGLAND 9 February 2009 MICHAEL P. TAYLOR SAUROPODS 2 Declaration Whilst registered as a candidate for the above degree, I have not been registered for any other research award. The results and conclusions embodied in this thesis are the work of the named candidate and have not been submitted for any other academic award. MICHAEL P. TAYLOR SAUROPODS 3 Acknowledgements First of all, from the bottom of my heart, I must thank my family for allowing me to spend so much time and money on what is ultimately something that I do only for fun. My wife Fiona has been unfailingly forbearing as I have repeatedly taken time away from her and our three sons, Daniel, Matthew and Jonno, to visit museums and attend conferences. Looking further back, I thank my mum, Marion, for encouraging me to be interested in everything around me, and my dad, Keith, for introducing me to the wonder of dinosaurs at an early age. I greatly regret that he is no longer with us to see the fruits of my labours; I know he would have been proud. I am indebted to my supervisor Dave Martill, not just for his advice and support during the last four years, but more important still for taking a punt on me in the first place. He had the insight and instinct to take me on back when I had nothing to recommend me as a Ph.D student – no publications, no training, no qualifications beyond a fifteen-year-old degree in an irrelevant subject that I'd forgotten 90% of. I will always be grateful to him for giving me this opportunity, and I hope that my work in this dissertation and elsewhere has repaid his faith in me. That I was able to approach Dave with even the little knowledge I did have is largely due to the education-by-stealth that I received from members of the Internet's Dinosaur Mailing List (http://dinosaurmailinglist.org) – most notably Tom Holtz, who has a rare gift for explaining complex concepts simply and briefly. I thank Mickey Rowe and Mary Kirkaldy for running the list so efficiently and providing a forum that has been so valuable to me. A palaeontologist is nothing without specimens, and I gratefully thank all those who have allowed me access to sauropod material, including but not limited to Sandra Chapman and Lorna Steel (Natural History Museum, London, UK), David Unwin, Wolf-Dieter Heinrich and Daniela Schwarz-Wings (Humboldt Museum für Naturkunde, Berlin, Germany), Nick Czaplewski and Jeff Person (Oklahoma Museum of Natural History, Norman, Oklahoma, USA) and Bill Simpson (Field Museum of Natural History, Chicago, Illinois, USA). I also thank the various journal editors who have handled my papers, and the many MICHAEL P. TAYLOR SAUROPODS 4 reviewers whose suggestions have so improved my work. Among reviewers, Jerry Harris deserves special mention: his unique brand of super-detailed yet always good-natured pedantry ensures that every manuscript that passes through his hands is much the better for it, and it has been my good fortune to spend many a long evening working through the literally hundreds of tiny corrections and comments that he includes in his reviews. My experiences of working in palaeontology have been overwhelmingly positive, with nearly everyone keen to encourage newcomers, share information, allow access to specimens, give credit where it is due and generally avoid treading on others' toes. Sadly this is not true of absolutely everyone in our field, and in the rare cases when ethics are violated, too many palaeontologists maintain a code of silence. During a recent such episode, Kevin Padian did not hesitate to speak up clearly and repeatedly – in contrast to too many other senior vertebrate palaeontologists. I thank him for his courage and clarity: it is people like him that keep this field so good to work in. Finally, I come to my colleagues. More people than I can list here have discussed interesting problems with me, supplied me with photocopies and PDFs of important papers, and generally provided an exhilarating sense of being part of a wider community. I will mention only two by name: my co-authors on the Sauropod Vertebra Picture of the Week blog (http://svpow.wordpress.com/), Darren Naish and Matt Wedel. I first encountered Darren on the Dinosaur Mailing List, where from his posts he seemed terrifyingly well-informed and ferociously opinionated. When I subsequently met him in person, I found that my initial impressions were spot on – he was and is all that and more. At the same time, he is excellent company (at least, to anyone interested in tetrapods), and it was on his recommendation that Dave Martill first considered accepting me as a student. Over the last few years, I have worked with Darren on several projects, and he is a truly outstanding collaborator – quick, conscientious, and with an appallingly comprehensive mastery of the literature, by which I mean basically everything published on any tetrapod since 1700. Only Darren's total inability to handle numbers keeps him down here with us mortals; were he able to perform simple addition, he would no doubt be a world-dominating evil genius by now. Last and absolutely not least, it my joy to thank Matt Wedel for his enormous contribution to getting me where I am today. Since that fateful day (9th January 2001) MICHAEL P. TAYLOR SAUROPODS 5 when I emailed him to ask for a copy of the Sauroposeidon paper, he has not only become one of my very best friends (second only to Fiona), but also an unofficial (and unpaid) additional supervisor, inducting me into the ways of sauropod science through a stream of informative and amusing emails while also maintaining a steady barrage on the subjects of Star Wars, ducks, Catholicism, biodiversity, the publishing business, killer rabbits, and why Sauron was the innocent victim of unprovoked Gondorian aggression. Matt's nerdy exterior conceals a mind that is not only relentlessly curious on the subject of palaeontology but also erudite, thoughtful and well informed on a startling range of other topics. My own enthusiasm for sauropod vertebrae is matched only by his, which makes him absolutely the best person to visit a collection with. He and I can happily sit for hours discussing the laminae on the single vertebra. He also, unlike Darren, appreciates the wonder of sushi. The bottom line is that without Matt's provocation, encouragement and occasional abuse, I would never have become any kind of scientist; and it is to him that I gratefully dedicate this dissertation. MICHAEL P. TAYLOR SAUROPODS 6 Contents Page Declaration 2 Acknowledgments 3 Contents 6 Assistance received 7 Abstract 8 Introduction 9 Bibliography for introduction 14 Chapter 1. Sauropod dinosaur research: a historical review 18–73 Chapter 2. A re-evaluation of Brachiosaurus altithorax Riggs 1903 75–141 (Dinosauria, Sauropoda) and its generic separation from Giraffatitan brancai (Janensch 1914) Chapter 3. An unusual new neosauropod dinosaur from the Lower 143–188 Cretaceous Hastings Beds Group of East Sussex, England Chapter 4. A new sauropod dinosaur from the Lower Cretaceous Cedar 190–238 Mountain Formation, Utah, U.S.A. Chapter 5. Vertebral morphology and the evolution of long necks in 240–280 sauropod dinosaurs Future work 282 Appendix: specimens inspected 283 MICHAEL P. TAYLOR SAUROPODS 7 Assistance received The introduction, chapters 1, 2, 4 and the appendices of this dissertation are entirely my own work, except that Mathew J. Wedel of Western University of Health Sciences contributed part B of figure 4 of chapter 4. Chapters 3 and 5 were co-authored, with myself as lead author in both cases. The work for these chapters breaks down as follows. Chapter 3 (description of Xenoposeidon): I was responsible for the anatomical part of the introduction, the systematic palaeontology section, description, comparisons and interpretation, phylogenetic analysis, length and mass calculations, diversity discussion, references, figures with their captions except figure 2, and both tables. Darren Naish of the University of Portsmouth was responsible for the geological and historical part of the introduction, the historical taxonomy section, and figure 2. Chapter 5 (evolution of long necks): this chapter was written by me as a consequence of a series of discussions with Mathew J. Wedel. Dr. Wedel also contributed figure 5. MICHAEL P. TAYLOR SAUROPODS 8 Abstract Although the sauropod dinosaurs have been recognised for more than a hundred and sixty years, much remains to be discovered and understood about their functional anatomy and palaeobiology. The taxonomy of older genera requires revision, and new taxa await description. The characteristic long necks of sauropods are mechanically perplexing and their evolution is obscure. All these issues are addressed herein. The well-known genus Brachiosaurus is represented by the American type species B. altithorax and the better known African species B. brancai. However, the referral of the latter to the genus Brachiosaurus was based mostly on symplesiomorphies, and an element-by-element examination of the overlapping material shows 26 differences between the species. B. brancai must be removed from Brachiosaurus and referred to the genus Giraffatitan, which has been previously proposed for it. Xenoposeidon proneneukos is a new neosauropod from the Lower Cretaceous Hastings Bed Group of the Wealden Supergroup, known from a single partial dorsal vertebra.
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