Move over T-rex, see you later Stegosaurus, adios Argentinosaurus. Scientists have announced that the bones of a new, even larger dinosaur have been found. Argentinosaurus currently holds the record for being both the heaviest land animal ever, and the longest, but the fossilized bones of the biggest dinosaur ever discovered have been found in Argentina. Scientists believe the species of titanosaur weighed in at 170,000 pounds, as heavy as 14 African elephants. A local farm worker found the remains which were captured by the BBC’s Natural History unit.
The fossils were then excavated by a team of palaeontologists from the Museum of Palaeontology Egidio Feruglio, led by Dr Jose Luis Carballido and Dr Diego Pol. They unearthed the partial skeletons of seven individuals – about 150 bones in total – all in ‘remarkable condition’. According to the measurements of its gigantic thigh bones, the herbivore would have been 40m (130ft) long and 20m (65ft) tall. Palaeontologists think it is a new species of titanosaur — part of a diverse group of sauropod dinosaurs that were characterised by their long necks and tails and small heads — dating from the Cretaceous period. The mega dino would have weighed in at 77 tons, making it seven tons heavier than the previous record holder Argentinosaurus. The creature, which lived in the forests of Patagonia between 95 and 100 million years ago, was yet to be named. “It will be named describing its magnificence and in honour to both the region and the farm owners who alerted us about the discovery,” the researchers said. The discovery came in the same week scientists confirmed the Argentinosaurus to be the biggest of them all. That plant-eating dinosaur weighed a earth-shaking 90 tons when it lived about 90 million years ago in Argentina, although the record has been broken by this new find.
Oxford University palaeontologist Dr Roger Benson, who led the study, says the dinosaur weigh-in included species ranging from small bird-like dinosaurs to well-known carnivores such as the Tyrannosaurus rex. The Tyrannosaurus rex, which weighed 7 tons, was the largest meat-eating dinosaur in the study, but it is small in comparison to the Argentinosaurus. A sparrow-sized bird called Qiliania, which lived about 120 million years ago in China, earned the distinction of being the smallest dinosaur, weighing a mere 15 grams. Dr Benson said Argentinosaurus, which roamed around South America, was about 6 million times the weight of Qiliania and that both still fit within the dinosaur family. ‘That seems amazing to me,’ he said. The largest meat-eating dinosaur was Tyrannosaurus rex, which weighed 7 tons and is also the largest known land predator of all time. The T. rex edged out another super predator that some scientists had once figured was bigger based on the length of its skull, Giganotosaurus, which lived alongside Argentinosaurus in ancient South America. The study estimated Giganotosaurus at about 6 tons, pretty darned big, but just a bit shy of dethroning T. rex. Dinosaurs had a remarkable run on Earth. They first appeared about 228 million years ago during the Triassic period, achieved stunning dimensions during the ensuing Jurassic Period and then disappeared at the end of the Cretaceous Period about 65 million years ago. All but the birds, that is. The mass extinction at the end of the Cretaceous, caused by an asteroid that hit Mexico, doomed most creatures but some birds survived. Benson said this study underscores the reasons that birds made it while their bigger dinosaur brethren did not. Other groups of dinosaurs such as long-necked sauropods like Argentinosaurus, the tank-like ankylosaurs, the duck-billed hadrosaurs, the spike-tailed stegosaurs and the meat-eating tyrannosaurs were essentially locked into a certain ecological niche. But birds filled all kinds of ecological niches with their widely diverse body sizes and ‘occupations’. Flying birds lived in all kinds of different habitats, both inland and coastal, and came in a wide range of sizes. But there also were large, ostrich-like flightless birds like Gargantuavis and flightless diving birds like Hesperornis. ‘It might be that they were simply much more ecologically diverse and that could have helped them survive an extinction,’ said Benson, who also noted that smaller creatures did a better job surviving the asteroid impact at the end of the Cretaceous. Paleontologist David Evans of Canada’s Royal Ontario Museum said dinosaur body size evolved relatively quickly early on in their time on Earth as they invaded new ecological niches, but then slowed down among most lineages. The exception was the maniraptoran lineage that led to birds, Evans added. More than 1,000 species of dinosaurs have been identified but many are known from only fragmentary fossil remains.