Humungous dino dwarfed T-rex

Will Dunham

The fossilised remains of a gargantuan plant-eating dinosaur, one of the largest animals ever to walk the Earth, has been found in Spain.

The giant would have been up to 38 metres long and weighed as much as seven elephants.

Turiasaurus riodevensis, named after the region and village in Spain where it was found, lived about 145 million years ago, the research team reports today in the journal Science.

It was a sauropod, the familiar kind of dinosaur with a long neck, long tail and massive body that walked on four stout legs.

Sauropods are the largest land animals in Earth's history and this particular one is the largest dinosaur ever found in Europe.

Previous dinosaurs of this scale have been found mostly in the Americas and Africa.

This one is emblematic of a previously unrecognised branch of European sauropod evolution, the scientists say.

"This discovery is the dream of a palaeontologist," says co-author Dr Luis Alcala of Fundación Conjunto Paleontológico de Teruel-Dinopolis in Spain. "Really, I'm not dreaming?"

The dinosaur came from a time right at the boundary between the latter two periods of the Age of Dinosaurs, the Jurassic and Cretaceous. Relatively little has been known about European dinosaurs dating from then.

Scientists believe this dinosaur spent its days munching plants in an area close to the shoreline of the ancient Tethys Sea, forerunner of the Mediterranean Sea.

The first bones were found in an abandoned wheat field near the village of Riodeva in northeastern Spain in May 2003, Alcala says.

Alcala says it weighed 40-48 tonnes and was 36-38 metres long. Tyrannosaurus rex was a baby by comparison, weighing just 6 tonnes and about 13 metres long.

The Spanish dinosaur's humerus, the bone in the front leg that extends from shoulder to elbow, was as big as a full-grown man.

Turiasaurus rivals the size of the largest known dinosaurs, all sauropods, and its remains were more complete than those of many of them.

These include the African giant Paralititan, Seismosaurus in North America and Argentinosaurus and Puertasaurus in South America.

"It's a tremendously large animal, not quite to the scale of the 'land whales', things like Argentinosaurus and Puertasaurus or Sauroposeidon. But it's pretty darned big," says Dr Thomas Holtz, a dinosaur expert at the University of Maryland who was not involved in the research.

"This is the first real super-giant from Europe," Holtz says.

Other fossils found at the site indicates Turiasaurus lived alongside other dinosaurs, including two-legged meat eaters, other sauropods and plant eaters similar to the armoured Stegosaurus. Turtles and crocodile-like reptiles were also around at the time.

The researchers say Turiasaurus was more primitive from an evolutionary perspective than other known giant sauropods.

The team found 70 pieces of the fossilised remains representing about a quarter of its skeleton, including fragments of the skull, leg, back, toes, ribs, shoulder blade and teeth.

Finding most of the key parts, the only vital missing piece was the pelvic girdle, allowed the scientists to ascertain its dimensions and appearance.

Other well-known sauropods include Apatosaurus (formerly known as Brontosaurus), Brachiosaurus and Diplodocus.

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This giant sauropod weighed a massive 48 tonnes, eight times more than Tyrannosaurus rex (Image: AAAS/Science/Carin L Cain)


About 145 million years ago, Turiasaurus would have munched on plants at the edge of what is now the Mediterranean Sea (Image: AAAS/Science/Carin L Cain)