A sauropod has been recorded in Antarctica for the first time.
Sauropods were the second most diverse group of dinosaurs, with over 150 recognised species that include some of the largest terrestrial vertebrates that ever existed. Their remains have been discovered in Africa, Asia, Australia, Europe and both North and South America.
Until last year, there was no record of sauropods remains on the Antarctic continent. A team of scientists, led by Ignacio Alejandro Cerda from CONICET in Argentina, has discovered the remains of a sauropod in shallow marine sediments on the Antarctic penisula.
In the study, published in The Science of Nature, the authors said “We report the first record of a sauropod dinosaur from Antarctica, represented by an incomplete caudal vertebra from the Late Cretaceous of James Ross Island.”
The discovery also confirms that some of the giants of the Cretaceous period lived in Antarctica. The size and morphology, particularly the distinctive ball and socket articulations, of the vertebra allows the researchers to identify it as belonging to a lithostrotian titanosaur.
Advanced titanosaurs emerged during the Early Cretaceous and were the predominant group of sauropods until the extinction of non-bird dinosaurs 65 million years ago. “Our finding indicates that advanced titanosaurs achieved a global distribution at least by the Late Cretaceous.”
Although they appear to have been one of the most widespread and successful species of sauropods, the origin and dispersal of the titanosaurs is not completely understood. The occurrence of lithostrotian titanosaurs in Antarctica could be explained by two hypotheses, according to the authors.
The first involves a dispersal event from South America to the Antarctic Peninsula during the Late Cretaceous. The second hypothesis suggests that titanosaur sauropods were already present in Antarctica during the Early Cretaceous or earlier.
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.”
Other important dinosaur discoveries, both marine and terrestrial, have been made in Antarctica in the last two decades, principally in the James Ross Basin.