The skeleton of the 37.2-metre animal - a titanosaur named Patagotitan mayorum, the "Patagonian Titan" - has just entered the exhibition hall of the Natural History Museum in London. Had its neck been raised, the dinosaur would have been the size of a five-story building, according to the researchers.

The replica of the titanosaur takes up residence in the same room of the museum where the popular "Dippy", famous cast of a diplodocus had been exhibited until 2017.

The dismantling of the dinosaur "Dippy", which had been sitting in the museum's main hall since 1979, had caused a wave of sadness among museum visitors, who had launched a petition "Save Dippy". It had been replaced by the skeleton of a blue whale, named "Hope".

The new skeleton on display is a replica of one of six titanosaurs, one of the largest dinosaurs to have existed on Earth, discovered after an Argentine farmer spotted a huge bone sticking out of the ground in 2010. The excavations then lasted until 2015.

The cast of the skeleton of a titanosaur named Patagotitan mayorum, the "Patagonian Titan" on display at the Natural History Museum in London, March 28, 2023 © JUSTIN TALLIS / AFP

"They discovered a cemetery of six different animals in the ground," Paul Barrett, the exhibition's scientific manager, told AFP. "For about three years, they excavated all these bones and were able to reveal that they had discovered a gigantic new type of dinosaur, one of the largest animals that ever walked the ground."

Mysterious death

The dinosaurs discovered lived in the forests of what is now Patagonia between 95 and 100 million years ago, during the Late Cretaceous period.

According to research, these gigantic herbivores could weigh some 57 tons, with a huge neck and a long tail. They had to eat 130 kilos of vegetation a day to support themselves.

Scientists believe that all six animals died at the same time, without knowing why.

The cast of the skeleton of a titanosaur named Patagotitan mayorum, the "Patagonian Titan" on display at the Natural History Museum in London, March 28, 2023 © JUSTIN TALLIS / AFP

"We don't know why they died... They may have been swept away by a flood. Or that they were killed by another environmental problem, such as a drought," Barrett said, adding that research is ongoing.

After the discovery in Argentina, experts made 3D scans of each dinosaur to create replicas made of polyester resin and fiberglass that they then mounted on a steel structure.

It took more than six months for a Canadian company to make this giant cast, from dozens of fossil bones extracted from the site.

The real bones would have been far too heavy to display, but the fact that they are replicas allows visitors to touch the cast.

The replica arrived in London in 32 separate crates, meaning "each piece had to be put together like a giant puzzle," said Sinead Marron of the Natural History Museum.

According to her, the aim of the exhibition is to "tell the story of the growth of an animal like this from a tiny egg, smaller than a football, to become this amazing giant of 57 tons".

Games and lines bring this story to life. Visitors will be able to touch the teeth of one of the titanosaurus' predators or even enter its internal organs to see how its lungs, heart and intestine work together.

© 2023 AFP