Giganotosaurus, meaning “giant southern lizard”, is a genus of dinosaur from the Late Cretaceous Period (98 to 96 million years ago). It thrived during the Cenomanian stage in what is now Argentina. The type species, G. carolinii, was named for Ruben Carolini, who discovered the fossils in 1993 in what is now known as the Candeleros Formation. The findings were published in the journal Nature in 1995.
This was one of the largest known terrestrial carnivores to roam the planet. It was larger than a Tyrannosaur but slightly smaller than the Spinosaurus. It was estimated to be about 41 feet in length and weighed between 6.5 and 13.5 tons. Although this dinosaur was larger than a tyrannosaur it had a much smaller brain. Its teeth were not as long nor wide as those of the tyrannosaur; However, the smaller teeth of the Giganotosaurus were more adapted for tearing or slicing flesh. It also had a good sense of smell.
Fossils of the Titanosaur found near the remains of the Giganotosaurus leads to speculation that the carnivorous Giganotosaurus preyed on the large herbivores. Some other fossils of species related to the Giganotosaurus that have been found to be pack hunters also lend to the idea that this beast was a pack hunter as well. Some theories indicate that this beast may have been able to achieve speeds of 31 mph.