Paleontologist Fernando Novas and his team discovered bones from the giant plant-eating dinosaur Puertasaurus reuili at Los Hornos Hill in southern Patagonia, Argentina, in January 2001.

The researchers found four vertebrae, or backbones, from the titanosaur. The fossils are estimated to be 70 million years old.

The National Geographic Society helped finance Novas' research. (National Geographic News is part of the National Geographic Society.)

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