A pack of Mapusaurus attacking a pair of Argentinosaurus.

The Mapusaurus was a dinosaur lived in Argentina 100 million years ago, a little before its close relative Giganotosaurus. It was a giant predator: current estimates speak of a length of 12.5 meters and a weight of at least 6 tons, surpassing the Tyrannosaurus than half a meter, but lighter than a ton. New fragmentary remains could still speak of a length greater than 14 meters and 7 tons, making it the most bulk of his more famous relatives Giganotosaurus and Carcharodontosaurus, but will need further research to validate these estimates. Probably hunted in packs, as there were found many Mapusaurus together, near the bones of a likely meal, nothing less than an Argentinosaurus, a dinosaur of exceptional size, to cut a long creature more than 30 meters of the hunt group is required.