Wednesday, 21 December 2011

The First Ever Antarctic Sauropod Dinosaur Fossils

The tail vertebra from the late Cretaceous, Antarctic dinosaur Lithostrotian
Dinosaurs were one of the most succesful animal groups ever to have lived on Earth. If it had not been for that fateful meteor 65 million years ago, it is very possible that many different lineages of these giant reptiles would still be alive today due to their extreme diversity, natural reptilian hardiness and ability to quickly adapt to new environments. They were also widespread in a geographical sense, with different species of predator and herbivore existing on all continents.

The largest were the sauropods. Remains of these ancient giants have been recovered from all continents except for Antarctica. This absence of vast herbivores from the now icy landmass has been noted by many palaeontologists. However, this huge gap in dinosaur evolution has been filled by recent fossil discoveries. A team, led by Dr Ignacia Alejandro Cerda from CONICET, Argentina, recovered an incomplete tail vertebra, belonging to the dinosaur Lithostrotian, from James Ross Island in Antarctica.

While this may not sound very exciting, analysis of the bone revealed that it came from an advanced species of titanosaur. The titanosaurs were the last great group of sauropod dinosaurs. They lived during the Cretaceous and this bone shows that, by at least the late Cretaceous, they, and hence the sauropods, were present on every single one of Earth's continents. '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' concluded Dr Cerda.