The amazing state of preservation of the bones is rare. The animals, all adults, appear to have died around the same time. The researchers speculate that they they succumbed to dehydration or got stuck in the mud while gathering around small pools of water to drink. In this deadly graveyard, the reptiles may have become food for scavengers like carnivorous dinosaurs in the Tyrannotitan genus.
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Based on the fossils of the newfound herbivore sauropod, which has yet to receive a name, scientists think it would have stretched 131 feet (40 meters) in length and weighed 80 tons (73 tonnes).
"It's like two semi trucks, one after another, and the equivalent of more than 14 African elephants' weight together," researcher José Luis Carballido, of Museum of Paleontology Egidio Feruglio in Argentina's Patagonia region, said in a statement.
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