Amargasaurus was a herbivore. It lived in the Cretaceous period and inhabited South America. Its fossils have been found in places such as Argentina.

Some 30 feet long, and weighing about three tons, this Argentinian sauropod from the early Cretaceous stood firmly on all four short legs with a long neck out in front, balanced by an equally long tail. Discovered in 1984, it has a unique claim to fame. Amargasaurus had a double row of long spines sticking up from its shoulders and back. Were they for defense, or display? The experts are still arguing.