Dinosaur hall of the Smithsonian’s National Museum of Natural History will be renovated; therefore, all of the specimens are being dismantled. Researchers suggest that investigation of separate bones during the dismantling could reveal new information about the age and origin of the ancient reptiles. The specimens will be delivered to the Research Casting International (RCI) in Toronto, Canada, one of the largest organizations that provide museum technical services such as mounting, molding, casting, preparation and restoration of specimens.
Administration of the museum decided to modernize the hall by changing its location and putting dinosaurs into new poses. The exhibition hasn’t been restored for decades. Some dinosaurs were mounted as early as in 1940’s and the museum itself was founded in 1910. During the century of the museum’s work, researchers learned a lot about anatomy, physiology and the age of dinosaurs. The restoration will provide scientists with an opportunity to investigate some stirring questions.
Matthew Carrano, who works as a curator of the dinosaur hall is looking forward to investigate bones of the Allosaurus. The specimen is a 17-foot-long predator of the Jurassic period with sharp, large teeth and powerful forelimbs. It has been on display since 1981, and what makes it special, is that the bones of this specimen come from the same individual. Usually, Allosaurus skeletons in the museums are constructed from many different individuals, which limits the extent of knowledge that scientisst can obtain from the specimen.
Deconstruction of the specimens is a tedious process. Employees of the Smithsonian’s National Museum of Natural History have to dismantle dinosaurs in reverse order–head and tail first. Some bones were held together with plaster, crystallized glue and steel armature. Those had to be cut through and removed. Each part of the dinosaur was tagged and, after the removal, it was packed carefully.
Carano wants to determine what kind of injuries the Allosaurus experienced during its life and how old it is. Scientists will cut out a cross-section of either a rib bone or a leg thin enough to investigate it under the microscope. The procedure of determining the dinosaur’s age is similar to counting the rings of a tree, because bones also have growth rings which are visible only under the microscope.
The particular Allosaurus specimen has some visible injuries. Its left shoulder-blade especially sparked scientists’ interest, and they investigated the specimen after the shoulder-blade and some ribs were exerted. It appears that bones healed improperly after the severe fracture. Fossil preparator, Steve Jabo, said: “It looked like [the Allosaurus] was whacked with a boulder or a sauropod tail.”
Another specimen, the Labrosaurus, will be compared with the Allosaurus because researchers suggest that these are relative species. However, there is only one bone that belongs to Labrosaurus, lower jaw with a trace of abscess and two missing teeth. By the coincidence, the Allosaurus specimen lacks the same bone; therefore, scientists suggest that the bones may come from the same dinosaur, and the Labrosaurus is not a separate individual.
Dinosaur skeletons are not completely dismantled at this point; therefore, the scientists of the Smithsonian’s National Museum of Natural History and other institutions will have to wait. Besides the investigation, there are plans to make some specimens smaller. For example, the Allosaurus’ chest is wider than it should be and some bones of its tail are artificial. Scientists think some of these bones are supernumerary and have to be removed. The restoration will take about four years; therefore, researchers will have sufficient time to investigate the fossils thoroughly before humanity will see the new dinosaur hall.
By Yevgeniya Migranova