Four vertebrae from the giant plant-eating dinosaur Puertasaurus reuili were found near Lake Viedma in Argentina's Santa Cruz Province. Viedma was formed by a melting glacier to the west. The ice scraped away vegetation on the cliffs surrounding the lake, leaving semi-arid brown hills.

Puertasaurus's chest alone was nearly 16 feet (5 meters) in diameter, about the size of an entire modern-day elephant.

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