Scientists discover dinosaur ‘heavier than herd of elephants’

The word big does not do justice to a massive, long-necked dinosaur that shook the Earth in Argentina about 77 million years ago.

Try colossal, enormous, gargantuan and stupendous — and you might come close to an accurate description of this behemoth, known to scientists as Dreadnoughtus schrani.

Scientists announced the discovery in southern Patagonia of remarkably complete and well-preserved fossil remains of the dinosaur, which weighed 65 tonnes and measured 85 feet long with a neck 37-feet long and a tail 30-feet long.

Palaeontologist, Kenneth Lacovara of Drexel University in Philadelphia, who discovered the dinosaur and led the effort for its excavation and analysis, said the scientists calculated its weight on the basis of the bones in its upper arm and thigh.

Dreadnoughtus weighed more than an adult sperm whale or a herd of African elephants. Tipping the scales at seven times as much as a T rex, it made the North American menace that also lived during the Cretaceous Period look puny.

Another giant Argentine dinosaur, Argentinosaurus, might have been larger, Lacovara said, but its scant remains do not allow a reliable weight estimate. Another group of scientists in May had cited Argentinosaurus, with an estimated weight of 90 tonnes, as the largest dinosaur.

While strictly a vegetarian, Dreadnoughtus was no pansy. With its size and a huge tail, it could have clobbered any predator foolish enough to attack it.

“We decided on Dreadnoughtus — meaning ‘fearer of nothing’ — because when you’re as big as this thing was, you’re probably not afraid of too much,” said Matt Lamanna, Carnegie Museum of Natural History in Pittsburgh.

“Not to mention we thought it was time a plant-eating dinosaur got a badass name. Those are usually reserved for the meat-eaters,” said Lamanna, a palaeontologist.

Lacovara said the name also was a nod to the powerful battleships called dreadnoughts, dating from the turn of the last century, that were designed to be impervious to attack.

Dreadnoughtus probably spent its days munching massive quantities of plants to fuel its enormous body. It was a member of a group of dinosaurs called titanosaurs that are thought to have been the largest that ever lived. Most titanosaurs are known only from fragmentary remains, but the scientists found 45% of the skeleton of Dreadnoughtus.

The researchers found two specimens of Dreadnoughtus side by side.

It appears they died and were buried after a river flooded and turned the ground into a soupy mixture of sand and mud.

The study appears in the Nature journal Scientific Reports.