Philip Currie of the University of Alberta in Canada speculated that pack hunting could have allowed Mapusaurs to prey on the biggest known dinosaur, Argentinasaurus, a 37.5m-long (125ft) plant-eater.
In the late Jurassic period, this fleet-footed plant eater, known as Dryosaurus altus, needed those powerful hindquarters to scurry away from its many predators.