Transylvanian Dinosaurs

CHAPTER 2. Dinosauria of Transylvania

15 CHAPTER 2 Dinosauria of Transylvania At the time of Franz Nopcsa’s death in 1933, the Haţeg fauna was thought to include five dinosaurs, a bird, a crocodile, a turtle, and a pterosaur. Unfortunately, work in Transylvania went fallow after the First World War, when the defeated Austro-Hungarian Empire ceded Transylvania to Romania. It was not until the mid-1970s that the collection of vertebrate fossils resumed in the Haţeg Basin. In 1978, two teams came together to follow in Nopcsa’s footsteps. One was supervised by Dan Grigorescu from Universitatea din Bucureşti, and the other was originally organized by Ioan Groza, later supervised by one of us (Jianu) and then by us both, under the auspices of Muzeul Civilizaţiei Dacice şi Romane Deva.∞ These two groups, plus a more recent joint expedition from Universitatea Babeş-Bolyai Cluj Napoca, Romania, and the Institut Royal des Sciences Naturelles de Belgique in Brussels (under the supervision of Vlad Codrea and Thierry Smith, respectively≤ ) have ventured to the outcrops at Vălioara, Densuş, and the Sibişel Valley, as well as several new locations, this time in the Transylvania Depression—Jibou (Sălaj County) in the north and Oarda de Jos, Vurpăr, Bărăbanţ, Lancrăm, Sebeş, and Vinţu de Jos in Alba County, along the southeastern margin of the Apuseni Mountains north and east of the Haţeg Basin.≥ These e√orts have amassed several thousand new fossil specimens and added considerably to the diversity of the known assemblages. Several di√erent kinds of dinosaurs are represented for the first time, as well as new bony 16 transylvanian dinosaurs fish, amphibians, mammals, lizards, and crocodilians. Along with this richer picture of the fauna has come a better understanding of the paleoecological context of the Haţeg Basin and other localities, as well as the evolutionary significance of this part of the world during the Late Cretaceous.∂ The best-known members of the Haţeg and similar assemblages clearly are the dinosaurs. Nopcsa knew or named nearly all of them, including Telmatosaurus transylvanicus and Zalmoxes robustus among ornithopods , the armored Struthiosaurus transylvanicus, the sauropod Magyarosaurus dacus, and a theropod he referred to Megalosaurus, a poorly known form first identified from the Middle Jurassic of England.∑ Given the Late Cretaceous age of these deposits, it is likely that many of these dinosaurs were among the last of their dynasties. In this chapter, we hope to accomplish two things. First, we want to put members of the Transylvanian menagerie into their evolutionary or phylogenetic context. Second, we want to breathe life into the fragments of ancient bones from Transylvania and, thereby, get a meaningful picture of these beasts that once roamed the Transylvanian region. We begin by outlining a field of study called phylogenetic systematics, otherwise known as cladistics. Cladistics is used to establish who is more closely related to whom among a group of organisms. We also use it to understand the relationships of the dinosaurs and their Transylvanian cohorts along the way. THE HISTORY OF LIFE AND HOW WE KNOW IT Fossils are the petrified remains of prehistoric life, something that has been recognized in the scientific community for three centuries, ever since the Danish scientist Nicholas Steno (1638–1686) first interpreted fossils as the vestiges of once-living creatures. Darwin understood that the links among these organisms constituted evolution, and he postulated a mechanism for the latter that depended not on divine design, but on the day-to-day action of environment on variable individuals within a population. He also understood that evolution, by its continual production of generations of descendants from earlier descendants, from still earlier descendants, and so on, back to primordial ancestry—in other words, diversification—was therefore hierarchical. It’s not for nothing that his canon—‘‘descent with modification’’—emphasized the hierarchi- Dinosauria of Transylvania 17 cal property of evolution. Others had already recognized this hierarchy in nature, most notably Carolus Linnaeus, the great eighteenth-century classifier of all organisms. His cataloging revealed that God’s creative hand had hierarchical tendencies, and all organismal taxonomies have had this structure thereafter. Darwinians and everyone since then have taken on Linnaeus’s practice of, if not his motivation for, identifying hierarchies in nature, because these nested sets of diversity conform to a single phylogeny, a single genealogy into deep time that...