Giganten
am Ende der Welt
Vortrag am 08.11.2010 in Dornbirn
Giants at the End of the World
Recent Dinosaur Discoveries
from Southernmost Patagonia, Argentina
Vortrag (in englischer Sprache) von
Kenneth J. Lacovara, Ph.D.
Drexel University, Philadelphia
08. November 2010 - 19:00 Uhr
inatura - Erlebnis Naturschau Dornbirn
Jahngasse 9 - A-6850 Dornbirn
http://inatura.at/
Eine gemeinsame Veranstaltung von inatura, ÖPG und ÖGG
Abstract
Sauropod dinosaurs were a diverse and cosmopolitan clade of long-necked, quadrupedal herbivorous dinosaurs that included the largest terrestrial animals ever. They appeared during the Late Triassic, ~215 Ma (million years ago), and remained abundant on most landmasses until the end of the Cretaceous (65 Ma). Although sauropods attained large body size early in their evolutionary history, exceptionally gigantic forms are reported only from the Middle Jurassic through the early stages of the Late Cretaceous (~170 - 86 Ma). Until recently, the last surviving sauropods (latest Cretaceous) were thought to be relatively diminutive compared with their predecessors.
Our discoveries in southern-most Patagonia, however, demonstrate the persistence of extremely massive sauropods through the end of the reign of dinosaurs. We recently excavated two specimens representing a new genus and species of titanosaurian sauropod. The first is represented by an isolated femur over 2 meters in length. The second consists of a largely complete, partially articulated skeleton. Previously discovered super-massive dinosaurs, such as Amphicoelias, Seismosaurus, Supersaurus, Sauroposeidon, Argentinosaurus, Paralititan, and Puertasaurus, are described only from fragmentary remains. Our new skeleton represents the most complete specimen yet of a dinosaur in the largest mass class. The record of large titanosaurian dinosaurs is especially fragmentary and this specimen provides an unprecedented opportunity to study the osteology and biomechanics of an enigmatic group of giants.
Additionally, the new titanosaurian dinosaur has possible polar affinities. Recent geophysical data indicates that Antarctica remained connected with South America until as late as 35 Ma. Cretaceous Antarctica is particularly mysterious in that it was ice-free and covered by boreal forest, yet still experienced six-months of darkness. Our new dinosaur may have been a denizen of this dark forest for which there is no modern analog. We are attempting to test this hypothesis with paleobiogeographic data from South America and Australia, which was also attached to Antarctica throughout the Cretaceous Period.
Kenneth J. Lacovara, Ph.D.
Dr. Kenneth J. Lacovara is an Associate Professor at Drexel University in the Department of Biology. He holds a Ph.D. in Geology from the University of Delaware and is an elected fellow of the prestigious Explorers Club. Recently featured in Men’s Journal as a member of The Next Generation of Explorers, Lacovara has built an international reputation for making spectacular paleontological discoveries at punishingly remote locations.
He has led five expeditions to southern-most Patagonia, where he recently excavated a new species of dinosaur, represented by the most complete skeleton ever discovered of an extremely massive dinosaur. Drexel University students dig alongside Dr. Lacovara and participate meaningfully in this project. In 2011 the Carnegie Museum of Natural History will feature Lacovara’s Patagonian research in an exhibit entitled The Frontiers of Science.
As a member of a Sino-American expeditionary team, Lacovara and colleagues discovered the fossilized remains of dozens of 115 million year old birds (Gansus yumenensis) in a remote mountain valley in western China. The team discerned that this Cretaceous age aquatic bird possessed surprisingly advanced anatomical features and in 2006 Lacovara co-authored a report in the journal Science describing Gansus as the "oldest-known essentially modern bird".
In Egypt, Lacovara co-led of a series of expeditions to the ancient and isolated Bahariya Oasis, located deep within the Sahara Desert. The team discovered a new species of dinosaur, which Lacovara named Paralititan stromeri. He co-authored a description of the new species in the journal Science, which garnered world-wide attention. Paralititan is notable as the second largest land-animal known and the first dinosaur fossil discovered in Egypt in nearly 100 years.
Closer to home, Lacovara has made some remarkable discoveries. With his class of Drexel paleontology students, he recently excavated a 65 million year old crocodile fossil from marine deposits in Gloucester County, New Jersey. The skeleton represents one of the most complete specimens of the extinct crocodile Thoracosaurus neocesariensis. He and his students regularly excavate fossil sting rays, sea turtles, and bird remains from the same ancient marine deposit.
Lacovara’s paleontological discoveries have received national and international acclaim. His work has been reported in hundred of newspapers, including front page stories in USA Today, The Times of India, The Times of London, Berliner Morgenpost, Al-Ahram, The New York Times, Los Angeles Times, The Washington Post, and The Philadelphia Inquirer, and in many magazines, including Time, Newsweek, US News and World Report, and National Geographic. He has been interviewed on television and radio programs, including CNN, NBC Nightly News with Tom Brokaw, Fox News, BBC News, and NPR’s Talk of the Nation: Science Friday. He is often called on by Philadelphia media for analysis of geoscience news pertaining to earthquakes, tsunamis, climate change, etc. Lacovara’s research in Egypt was the subject of a two-hour A&E documentary entitled The Lost Dinosaurs of Egypt. He is also co-author of the Lost Dinosaurs of Egypt book, published by Random House. In the 2008 History Channel documentary, Prehistoric Monsters Revealed , Lacovara guided viewers on a two-hour tour of Earth history, while introducing them to some of the most bizarre creatures to ever walk, fly, swim, or slither. His most recent documentary, Monsters Resurrected: Spinosaurus, debuted in December, 2009 on the Discovery Channel and is available now on Netflix.
© Österreichische Geologische Gesellschaft
