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Giganotosaurus

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Giganotosaurus is a genus of massive theropod dinosaurs. Theropods are a group of dinosaurs that walk on two legs. This specific genus lived in what is now Argentina. It existed during the early Cenomanian age of the Late Cretaceous period. This was approximately 99.6 to 95 million years ago. Giganotosaurus was one of the largest known terrestrial carnivores to ever walk the Earth.

Giganotosaurus BW
Giganotosaurus BW

The anatomy of Giganotosaurus shows how it functioned as an apex predator. Its skull was relatively low. The nasal bones were rugose, meaning they were rough and wrinkled. It also possessed a ridge-like crest on the lacrimal bone in front of the eye. The teeth were compressed sideways and featured serrations. These serrations are tiny ridges that help cut through flesh. The lower jaw featured a downward-projecting process at the tip, which looked like a chin. This chin may have helped the animal resist stress during a powerful bite.

Giganotosaurus skull reconstruction
Giganotosaurus skull reconstruction

Scientists believe Giganotosaurus was homeothermic. This means it had a type of warm-bloodedness. Its metabolism likely sat between that of a mammal and a reptile. This efficient metabolism would have enabled fast growth. As an apex predator, it likely hunted other dinosaurs. It may have specifically fed on juvenile sauropod dinosaurs.

Hunting season in Argentina
Hunting season in Argentina

The discovery of this dinosaur began in 1993. An amateur fossil hunter named Ruben Carolini found a tibia, or lower leg bone. He was driving a dune buggy in the badlands near Villa El Chocón in Patagonia. Specialists from the National University of Comahue arrived to excavate the site. Paleontologists Rodolfo Coria and Leonardo Salgado announced the find in 1994. They named the species Giganotosaurus carolinii in 1995. The name translates to "giant southern lizard." The specific name honors the discoverer, Carolini.

205 Arg ElChocon Museo Giganotosauro
205 Arg ElChocon Museo Giganotosauro

Determining the exact size of Giganotosaurus is a subject of intense scientific debate. The holotype specimen is almost 70% complete. Estimates for this specimen suggest a length of 12.5 meters. It may have weighed approximately 6,700 kilograms. However, other bones suggest even larger sizes. A dentary bone, which is part of the lower jaw, was found that was 8% larger than the holotype. This bone suggests an individual could reach 13 meters in length. Some researchers suggest the animal could reach 14.3 meters.

Giganotosaurus specimens
Giganotosaurus specimens

This debate often compares Giganotosaurus to Tyrannosaurus. For many years, Tyrannosaurus was considered the largest theropod. Some researchers argue Giganotosaurus was larger. They note the femur of Giganotosaurus was 5 cm longer than the femur of "Sue," a famous Tyrannosaurus specimen. Other scientists argue the animals were roughly equal in size. They suggest some Giganotosaurus estimates might be exaggerated. These discussions help paleontologists understand the limits of how large a bipedal animal can grow.

Longest theropods
Longest theropods

Giganotosaurus belongs to the family Carcharodontosauridae. This group includes other massive theropods like Mapusaurus and Tyrannotitan. It is one of the most completely known members of this family. Studying these animals helps scientists understand Late Cretaceous ecosystems. It also shows how large predators were distributed across different continents.

Mapusaurus Roseae restoration
Mapusaurus Roseae restoration

You can visit the fossils in Argentina today. The holotype skeleton is housed in the Ernesto Bachmann Paleontological Museum. It is displayed on a sandy floor in a room dedicated to the animal. This museum was inaugurated in 1995 at the request of Ruben Carolini. The museum also features a mounted reconstruction of the skeleton in an adjacent room.

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🖼️ Images & Media (23)
File:205 Arg ElChocon Museo Giganotosauro.JPG
205 Arg ElChocon Museo Giganotosauro.JPG
File:Reconstrucción del esqueleto de Giganotosaurus en el Museo Paleontólogico Ernesto Bachmann.JPG
Reconstrucción del esqueleto de...
File:Lady Giga im Hbf Ffm DSC 5432.jpg
Lady Giga im Hbf Ffm DSC 5432.jpg
File:Longest theropods.svg
Longest theropods.svg
File:Giganotosaurus specimens.svg
Giganotosaurus specimens.svg
File:Giganotosaurus skull reconstruction.png
Giganotosaurus skull reconstruction.png
File:Allosauroid lacrimals.png
Allosauroid lacrimals.png
File:Fernbank Museum- Argentine Dinosaur Exhibit Giganotosaurus from above.jpg
Fernbank Museum- Argentine Dinosaur...
File:Giganotosaurus BW.jpg
Giganotosaurus BW.jpg
File:Giganotosaurus in Helsinki.jpg
Giganotosaurus in Helsinki.jpg
File:Non-avian theropoda quadrate openings.png
Non-avian theropoda quadrate openings.png
File:Neovenator.png
Neovenator.png

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