Amargasaurus (“Amarga lizard”) was a sauropod dinosaur who lived during the Early Cretaceous, about 135 million years ago. Gondwanan sauropods seemed to have survived longer than their Laurasian counterparts. Amargasaurus is thought to be related to Dicraeosaurus, another Gondwanan dinosaur. (Dicraeosaurus is part of the famous Tendaguru fauna of Tanzania which also includes Brachiosaurus brancai and the stegosaur Kentrosaurus aethiopicus.) The original skeleton was found by José Bonaparte and Guillermo Rougier in 1984 in Neuquén Province, Patagonia, Argentina. Almost all of it was found and it shows that Amargasaurus was about 30 feet (9 meters) long. The most amazing features of Amargasaurus are its long neural spines. Some of them are 21 inches (50.5 cm) long! Because of this, paleontologists think that Amargasaurus may have had a “sail” on its neck. Why? To scare off predators and rivals, to control body temperature, or to attract lady-amargasaurs? Only the back part of the skull of this skeleton was found — its reconstruction was based on the skull of Dicraeosaurus.
