Cuban Dinosaur: First Confirmed Remains Discovered
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Cuban Dinosaur: First Confirmed Remains Discovered National Geographic News December 20, 2002 Scientists from Cuba and Argentina have uncovered the first positively identified dinosaur remains ever found in Cuba. The roughly 150-million-year-old vertebra of a small, coastal-dwelling Saurischian dinosaur was unearthed in the Sierra de los Organos Mountains in western Cuba. Earlier discoveries had been made, but none of the finds were able to withstand scientific scrutiny. In 1949, Alfredo de la Torre y Callejas found a 45-centimeter (18 inch) bone in Vinales and identified it as that of a Diplodocus or Brontosaurus. The bone was lost, however, and the very general description and single photograph that have survived leave doubt about its true origins. Despite the lack of hard evidence, scientists remained convinced that dinosaur fossils could be found in what is now Cuba. "I was suspicious that there must be dinosaur remains in western Cuba, but had been unable to prove it," said Manuel Iturralde-Vinent, a paleontologist at Cuba's Museo Nacional de Historia Natural. "Now we are confident that there are fossil remains of dinosaurs." Until more fossilized remains are found it isn't possible to identify what kind of dinosaur the vertebra belonged to, but the discovery of any land-dwelling dinosaur in Cuba is significant, said Zulma Gasparini, a paleontologist at Argentina's Museo de La Plata. Gasparini and Iturralde-Vinent are the lead scientists on the project. "They were undoubtedly land animals, and consequently they provide some evidence to confirm or refute hypotheses on land-seas distribution in the Caribbean," he said. "They could also add crucial knowledge of the evolution and geographic distribution of dinosaurs, and other land groups, between both Americas." On Land and in Sea "The occurrence of Jurassic land and coastal sediments in western Cuba is well-known," said Iturralde-Vinent. "In these sediments I have been looking for dinosaurs for many years, and in the end the search was successful as we located a small bone. This find opens great possibilities for future research." The dinosaur bone was found in layers of earth from the Late Jurassic Jagua Formation in what had once been coastal sediments. "The deposits where the bones are found accumulated 154 to 146 million years ago in shallow marine waters very close to the shore, allowing representatives of land and marine elements be found in the same beds," said Iturralde-Vinent. Abundant remains of terrestrial vegetation such as fern trees, the fossil remains of at least two species of pterosaurs—extinct flying reptiles—and marine reptile fossils were found in the same strata. Iturralde-Vinent notes that such a mixture of terrestrial and marine animals is not unusual in paleontology. "The only dinosaur known from Antarctica was a fossil remain found in marine sediments," he explained. "Sometimes the animal dies and a river might carry the floating body into open waters. The bodies can float while they are in the process of decomposition." Expeditions in the last several years have led to the discovery and description of several new taxa of gigantic ancient aquatic reptiles (pliosaurs, plesiosaurs, and ichthyosaurs), as well as crocodiles, turtles, and flying reptiles (pterosaurs). New species of turtle, Caribemys oxfordiensis, and plesiosaur, Vinalesaurus caroli, were recently discovered, as was a pterosaur that had a tail and soared in the prehistoric skies with a wingspan of nearly 4 meters (13 feet). The search for Jurassic fossils in Cuba is a joint project of the Museo Nacional de Historia Natural of Cuba and the Museo de La Plata in Argentina, and is partially funded by the National Geographic Society. Evidence of Ancient Land Distribution Iturralde-Vinent and Gasparini continue to search the site for more dinosaurs and related fossils, and are in the process of describing several new species of Jurassic reptiles for scientific publication. They are also expanding their research to test a theory about the Late Cretaceous paleogeography of the Americas. Many scientists speculate that at the end of the Cretaceous period (approximately 80-60 million years ago) there was a land connection between North and South America across the extinct volcanic islands that now comprise parts of the Greater Antilles. Sea levels and the position of the islands have changed significantly since that ancient period. The presence of dinosaur remains on the islands would lend credence to the theory, and Iturralde-Vinent has been searching rock formations in the Greater Antilles for dinosaur fossils since 1997. "As yet, this search has been unsuccessful," he said, "perhaps because rocks of late Cretaceous age are strongly weathered and the potential bones are hard to find on the surface. But I will continue to search." Hikers in Cuba's Valle de Viñales National Park pass an exposed ammonite fossil. Most of modern-day Cuba was submerged beneath a shallow sea during the Cretaceous period, and the limestone outcrops of the Viñales region are strewn with marine fossils from the Cretaceous as well as the Jurassic. .