The remains of a meat-eating dinosaur thought to have weighed three tonnes more than the star of Jurassic Park have gone on display The Giganotosaurus - a dinosaur that roamed South America about 100 million years ago and may have been the biggest meat-eater known - has made its North American debut at the Academy of Natural Sciences. The museum is showing the first reconstructed skull of the Giganotosaurus, discovered in the Patagonia region of Argentina in 1994. A reconstructed skeleton, 80 per cent complete, is to be displayed until September. The dinosaur lived about 30 million years before Tyrannosaurus rex, said paleontologist Rodolfo Coria, who excavated the Giganotosaurus. The specimen excavated by Mr Coria was about 14 metres long, weighed eight tonnes and stood 3.5 m tall on two legs. Tyrannosaurus rex, by comparison, was estimated to be about 10 to 12 m long, weighed five tonnes was about three metres tall. Whether Giganotosaurus was meaner than Tyrannosaurus rex is anybody's guess. But there's no doubt it was an efficient killing machine. The beast's two-metre skull is shaped like a pair of scissors. It had a mouthful of narrow arrowhead-shaped serrated teeth, some 20 cm long, that eviscerated its victims with surgeon- like precision. Victims included 23 m-long plant-eaters, whose fossils were found nearby. The Tyrannosaurus used brute strength, packing more power with its thicker teeth. 'The Giganotosaurus was bigger and lighter built,' said Michael Brett-Surman, of the Smithsonian Institution. 'T Rex is a statement of bulk and power.' The Giganotosaurus has thrilled children mad about dinosaurs. 'They were all very happy to find a dinosaur bigger than T Rex,' Mr Coria said.