October 29, 2012
Sauropods were magnificent dinosaurs. These long-necked, small-headed titans were unlike anything that has evolved before or since, and they were so strange that paleontologists are still debating the basics of how Apatosaurus and kin actually lived. As iconic as their skeletons are now, though, the first sauropod ever described was initially envisioned as a very different sort of creature. The great Cetiosaurus was originally seen as a gargantuan, plesiosaur-crunching crocodile.
In 1841, the British anatomist Richard Owen described a curious collection of limb bones and vertebrae found at various locations in England. The limb elements reminded Owen of the same bones in crocodiles, and the vertebrae were reminiscent of those in whales. The scattered elements seemed to correspond in structure to aquatic animals, and since function was dictated by skeletal form, Owen believed that Cetiosaurus–the “whale lizard”–must have been a marine predator larger than anything that had been found before.
The following year, in his massive Report on British fossil reptiles, Part II, Owen reassessed the various prehistoric reptiles from his country. This was the landmark monograph in which Owen coined the term “Dinosauria,” but he didn’t include Cetiosaurus within the newly named group. The animal seemed vastly different from Megalosaurus, Iguanodon and Hylaeosaurus. Dinosaurs, in Owen’s view, were terrestrial animals with upright limbs, and he saw Cetiosaurus as a marine carnivore. Owen grouped the poorly known animals with crocodiles, instead.
It wasn’t until 1869 that Cetiosaurus was formally recognized as a dinosaur. Thomas Henry Huxley, Owen’s chief academic rival, proposed that Cetiosaurus was a close relative of Iguanodon, although he later changed his mind and suggested that the puzzling animal was an oddball that didn’t belong with crocodiles or dinosaurs. Other researchers were more confident that Cetiosaurus belonged among the dinosaurs. John Phillips, in an 1871 monograph, proposed that Cetiosaurus was an herbivorous dinosaur, and in 1875 Owen conceded that his creature was a huge, aquatic dinosaur.
Like many other early dinosaur finds, the identity of Cetiosaurus was obscured by a lack of material and the unfamiliarity of the Mesozoic curiosities. When O.C. Marsh, E.D. Cope and other North American paleontologists began to uncover relatively complete skeletons of dinosaurs such as Diplodocus and “Brontosaurus” from the American West during the late 19th century, a more accurate vision of Cetiosaurus as a sauropod started to come into focus. All the same, researchers named multiple species of this dinosaur from various sites of different ages. Cetiosaurus became a taxonomic wastebasket for numerous scrappy sauropods found in England.
Paleontologists Paul Upchurch and John Martin sorted out the mess in 2003. Out of 13 different species named from bones belonging to different kinds of sauropods that lived millions of years apart, Upchurch and Martin recognized only one valid taxon–Cetiosaurus oxoniensis. This sauropod trod Jurassic England around 170 million years ago. And even though our knowledge of this dinosaur’s skeleton isn’t yet complete, discoveries both old and new have helped paleontologists outline what this historically significant dinosaur was like.
In 1868, quarry workers at Bletchingdon Station (near Oxford, England) uncovered a Cetiosaurus bonebed containing a trio of skeletons, one being much larger than the others. These bones formed the basis of Phillips’ study of the dinosaur, and, as Upchurch and Martin noted, “potentially represents one of the best preserved sauropods from the Jurassic of Europe.” A century later, in 1968, workers at Williamson Cliffe Brickworks in Rutland discovered bones in their quarry, and some of the remains were briefly described by M.D. Jones in 1970. Upchurch and Martin reexamined the Rutland material as part of their bigger Cetiosaurus project and found that the individual dinosaur is represented by an almost complete neck, various parts of the spinal column and limb elements, making it one of the best-preserved Cetiosaurus ever found.
Altogether, the bones of Cetiosaurus indicate that the sauropod was medium to large in size, though exactly how big this dinosaur was isn’t clear. (Estimating the length and mass of incompletely-known dinosaurs is a difficult task.) What makes Cetiosaurus of special interest to paleontologists, though, is that it was a relatively archaic form of sauropod. Most of the famous sauropods–Diplodocus, Camarasaurus, Brachiosaurus and their ilk–belong to lineages within a big group called the neosauropoda. Cetiosaurus seems to fall just outside this group, and so the dinosaur might clue paleontologists in to what sauropods were like just before the fantastic radiation of neosauropods during the Late Jurassic. It took three decades to change the animal from a crocodile to a dinosaur, and a century more for the sauropod’s identity to be untangled, but, now that the dinosaur has a definite name and evolutionary identity, paleontologists can start to investigate the biological secrets locked inside Cetiosaurus bones.
Check out previous entries in the Dinosaur Alphabet here.
Naish, D. 2009. The Great Dinosaur Discoveries. Berkeley: University of California Press. pp. 30-31
Upchurch, P., Martin, J. 2003. The Anatomy and Taxonomy of Cetiosaurus (Saurischia, Sauropoda) from the Middle Jurassic of England. Journal of Vertebrate Palaeontology 23 (1): 208–231
Upchurch, P., Martin, J. 2002. The Rutland Cetiosaurus: the anatomy and relationships of a Middle Jurassic British sauropod dinosaur. Palaeontology, 45: 1049–1074.
Wilson, J. 2005. Overview of sauropod phylogeny and evolution, pp. 15-49 in Curry Rogers and Wilson (eds.), The Sauropods: Evolution and Paleobiology, Berkley: University of California Press.
August 8, 2012
Museums are where dinosaurs rest, but art is where dinosaurs live again. No press release about a newly-discovered dinosaur, or some new fact about an already-known dinosaur’s lifestyle, is complete with a beautifully-rendered artist’s restoration. And dinosaur art keeps improving. Since the time of the Dinosaur Renaissance in the late 20th century, artists have taken ever more care in rendering the prehistoric creatures and the habitats they called home. Truly, dinosaurs have never looked better, and the new coffee table book Dinosaur Art: The World’s Greatest Paleoart showcases some of the best fossil restorations by today’s foremost paleoartists.
When I first received Dinosaur Art in the mail, I wondered how it was going to set itself apart from similar books. The glossy Dinosaur Imagery showcased some of the most exquisite dinosaur art created since the 1970s, Allen Debus’ Paleoimagery tracked the changing images of dinosaurs during the past century and Jane Davidson’s A History of Paleontology Illustration documented the scientific and popular aspects of accurately portraying dinosaurs. Where Dinosaur Art differs, I found, is that the book puts the emphasis on the artists themselves–from their favorite prehistoric creatures to the techniques they use. And while veteran paleoillustrators such as the incomparable Doug Henderson and the highly-influential John Sibbick are included in the book, the focus is on relative newcomers who have only recently started to shape our image of dinosaurs.
Dinosaur Art speaks to two audiences. If you can’t get enough restorations of prehistoric life–the book focuses on dinosaurs, but also includes ancient mammals and other non-dinosaurs–then Dinosaur Art is an absolute must-have. Even though I had seen much of the artwork before, I didn’t fully appreciate Raúl Martín‘s gorgeous Mesozoic landscapes or Todd Marshall‘s spiky, intricately-detailed dinosaurs until I saw them laid out in high-definition right in front of me. There are even a few fold-out panels, showing the stunning murals by artists such as Julius Csotonyi. Dinosaur Art is an absolute pleasure to pore over, and almost every page is a window into a vanished world.
The book is more than a gallery, though. For many aspiring dinosaur artists, the artist interviews make this book an essential resource. Each artist describes their process, preferred materials, whether digital or more traditional, and how they fill out creatures that we often only know from bones. Many of the questions asked to the artists are consistent from one interview to the next, which easily contrasts the styles and personalities of each. While Gregory S. Paul‘s answers are short and curt, the interviews with Douglas Henderson and Luis Rey feel warmer and more conversational. Together, the lavish art and interviews will undoubtedly inspire the next generation of great paleoartists.
But there’s another reason why Dinosaur Art is an essential book for any dinosaur fan. The collection is a printed milestone of what we currently understand about dinosaur lives, and will act as a baseline as our knowledge of prehistoric life changes. Artists have been altering their work and racing to keep up with the latest discoveries for well over a century; that trend will almost certainly continue. As we discover new dinosaurs and investigate the biology of those we already know, dinosaur art will continue to evolve.
Dinosaur Art is set to debut on September 4, 2012.