Paleontologists announced Thursday the discovery in Australia of fossilized bones of a giant dinosaur species unknown until now, whose ancestors came from South America via Antarctica, approximately 105 million years ago.
Dubbed Savannasaurus elliottorum, the long-neck dinosaur belongs to the family of sauropods, the dinosaur family that houses the largest animals that ever walked the face of the Earth. Savannasaurus elliottorum was herbivorous and measured at least 14 meters long.
The discovery of his remains in Queensland (northeast of Australia) — as well as that of another sauropod named Diamantinasaurus matildae — was published in the journal Scientific Reports.
The team of paleontologists behind the publication dubs both specimens Wade and Matilda.
These two species do not seem to have existed in Australia. Their discovery should reopen the debate on the origin and date of arrival of the dinosaurs in this part of the world.
According to some experts, they arrived well before the Cretaceous period, which began 145 million years ago and ended 66 million years ago with the impact of a giant meteorite, which led to the disappearance of half of all living species on Earth, including terrestrial dinosaurs.
However, this new discovery suggests another scenario, according to Stephen Poropat, a paleontologist at the University of Uppsala, Sweden, and lead author of the study.
“We suggest that our sauropods descended from South American ancestors,” which would have traveled along a strip of land to the Antarctic, skirting the continent, and then through another strip of land to Australia.
During the greater part of the Cretaceous, Antarctica was too cold to allow these large herbivores to survive such a journey, recognizes Mr. Poropat.
But a warming period occurred about 105 million years ago, which could make possible this passage from the south, he believes.
According to the excavations, the Antarctic continent, now covered with a thick layer of ice, was indeed covered with forests at that time.