An amateur in a dune buggy found a rival to Tyrannosaurus
In 1993 Rubén Carolini was driving a dune buggy through the Patagonian badlands when he spotted a huge leg bone. It belonged to Giganotosaurus, a predator up to about 13 metres long that lived around 110 million years ago and has fuelled a long argument over whether it outsized Tyrannosaurus.
The find came near Villa El Chocón in Neuquén province, Argentina. Specialists from the National University of Comahue excavated it, and paleontologists Rodolfo Coria and Leonardo Salgado announced it at a 1994 scientific meeting, where the science writer Don Lessem offered to pay for the dig after seeing a photo of the shinbone. The skeleton turned out to be almost 70 percent complete, including most of the backbone, both hips and shoulders and the thigh bones, though the skull was scattered across about 10 square metres. In 1995 Coria and Salgado named it Giganotosaurus carolinii: giant southern lizard, with the species name honouring the discoverer.
The animal lived in the Albian stage of the Early Cretaceous, roughly 111 to 106 million years ago. Estimates for the best specimen give a length of 12 to 13 metres, a skull up to 1.8 metres long and a weight anywhere between 4.2 and 13.8 tonnes; a jawbone from an apparently bigger individual suggests 13.2 metres. Some researchers conclude it was larger than Tyrannosaurus, long thought the biggest theropod, while others see the two as roughly equal and the top estimates as inflated.
It belonged to the carcharodontosaurids, a family of giant meat-eaters that includes Mapusaurus and Carcharodontosaurus, and is one of its best-known members. The skull was low, with rough, wrinkled nasal bones, a crest in front of each eye, and blade-like serrated teeth. A downward-pointing chin at the front of the lower jaw may have helped absorb stress during bites. Scientists think it was warm-blooded to a degree, with a metabolism between a mammal's and a reptile's, and able to snap its jaws shut quickly. As top predator it may have hunted young sauropods.
The original skeleton is the centrepiece of the Ernesto Bachmann Paleontological Museum in Villa El Chocón, founded in 1995 at Carolini's request, where it lies on sand beside the excavation tools, with a mounted reconstruction next door.
Source: Giganotosaurus
