CHICAGO — The newest addition to the Field Museum on Chicago’s lakefront will give visitors a glimpse of the largest predatory dinosaur yet discovered via a 46-foot cast of a Spinosaurus skeleton suspended high above the museum’s main hall.
Field Museum officials unveiled the cast with its distinctive fin and crocodile-like jaws last week. It is now available for visitors.
Scientists have long struggled to interpret Spinosaurus fossils to determine the animal’s behavior in life, uncertain whether it swam while hunting or simply waded into water in search of prey. Field Museum researcher Matteo Fabbri said the cast is about 60 percent of a skeleton, the most complete specimen of the species.
“Spinosaurus is a very weird animal,” Fabbri said. “The proportions of the entire body are incredibly weird in comparison to any other dinosaur. The tail is extremely long, the legs are incredibly short, and the skull reminds (us) of the ones we find in modern crocodiles.”
Fabbri is among a team of researchers who in March published an article concluding that the density of Spinosaurus fossils means they likely did go underwater to hunt. The team compared fossils with other dinosaurs, extinct marine reptiles and living animals including seals and whales — knowing that animals that swim underwater for food have bones that are nearly solid compared to those that remain on land.
The exhibit team at the Field decided to display the Spinosaurus cast with that finding in mind, said Ben Miller, Field Museum exhibition developer.
“We decided to put Spinosaurus in a swimming pose because that’s how it would have spent most of its life,” Miller said. “This is a semiaquatic animal. It would have lived kind of like a crocodile, kind of hanging around in rivers, catching fish.”
According to the museum, a team of artists in Italy created the cast based on fossils found in Africa’s Sahara Desert where the Spinosaurus lived nearly 100 million years ago. The original fossils are kept at the Hassan II University of Casablanca in Morocco.
The only other cast of a Spinosaurus is on display in Japan.