Have you ever wondered how museums assemble the gargantuan dinosaur fossil skeletons that dominate their halls? This video from The American Museum of Natural History in New York documents that process, and shows how it went about mounting their newest dinosaur tenant. The species being prepared for display hasn’t been formally named by scientists yet, but it’s part of a family called titanosaurs.
The titanosaur you see was built based on fossil bones excavated in Patagonia in 2014. It’s 122 feet long—so long that its head peeks out of the hall it calls home, ready to greet visitors. When titanosaurs roamed the earth, they weighed about 70 tons. Because of the dinosaur’s massive size, the bones are too heavy to mount, so the skeleton you see in the video is actually a cast reproduction. This isn’t unusual: the museum hosts a combination of casts and actual fossils. Five of the original fossils discovered in Patagonia are on display in the exhibit.
It took six months to create the titanosaur cast, and the process was meticulous. First, the bones were 3-D scanned, then styrofoam replicas were made. From there, the styrofoam replicas were used to make casts of fiberglass. Eighty-four of the bones were cast from originals found on site, while the rest of the skeleton was filled in with new bones based on observations of similar dinosaurs. Next, the bones were attached to a steel armature—the metal frame that holds the dino up. Last, the creature was painted to match the actual fossils.