December 19, 2011

Plant-Eating Dinosaur Discovered In Antarctica

First record of a sauropod dinosaur in Antarctica suggests more widespread distribution of this species than previously thought

For the first time, the presence of large bodied herbivorous dinosaurs in Antarctica has been recorded. Until now, remains of sauropoda - one of the most diverse and geographically widespread species of herbivorous dinosaurs - had been recovered from all continental landmasses, except Antarctica. Dr. Ignacio Alejandro Cerda, from CONICET in Argentina, and his team's identification of the remains of the sauropod dinosaur suggests that advanced titanosaurs (plant-eating, sauropod dinosaurs) achieved a global distribution at least by the Late Cretaceous*. Their work has just been published online in Springer's journal, Naturwissenschaften — The Science of Nature.

Sauropoda is the second most diverse group of dinosaurs, with more than 150 recognized species. It includes the largest terrestrial vertebrates that ever existed. Although many sauropod remains have been discovered in North and South America, Africa, Asia, Australia and Europe, there is no previous record of sauropoda in Antarctica. Other important dinosaur discoveries have been made in Antarctica in the last two decades - principally in the James Ross Basin.

Dr. Cerda and colleagues report the first finding of a sauropod dinosaur from this continent and provide a detailed description of an incomplete middle-tail vertebra, recovered from James Ross Island. The specific size and morphology of the specimen, including its distinctive ball and socket articulations, lead the authors to identify it as an advanced titanosaur.

These titanosaurs originated during the Early Cretaceous and were the predominant group of sauropod dinosaurs until the extinction of all non-bird dinosaurs at the end of the Cretaceous. Although they were one of the most widespread and successful species of sauropod dinosaurs, their origin and dispersion are not completely understood.

The authors conclude: "Our discovery, and subsequent report, of these sauropod dinosaur remains from Antarctica improves our current knowledge of the dinosaurian faunas during the Late Cretaceous on this continent."

*The Cretaceous Period spanned 99.6-65.5 million years ago, and ended with the extinction of the dinosaurs.


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