Sunday, July 31, 2016
Spinosaurus was the star of the film Jurassic Park III. This drew a resounding set of complaints, since the Spinosaurus displaced the T. rex as the film's antihero.
A large number of amateur paleontologists also criticized the film for depicting Spinosaurus as a predatory land animal, when its snout and teeth clearly indicated a fish-eating animal which spent a good deal of its time in water.
The first Spinosaurus remains were discovered in western Egypt in 1912, and given the name Spinosaurus aegyptiacus. This specimen was destroyed during World War II when the British bomed the Paläontologisches Museum München on the night of April 24-25, 1944. In 1996, a second species, S. maroccanus, was described, although most paleontologists now think this is incorrect and that only a single species existed.
Spinosaurus was enormous -- the largest of all known carnivorous dinosaurs. Estimates are that it reached 50 to 60 feet in length. It had distinctive spines growing out of its backbone, which grew up to 5.5 feet in length. They mostly likely were covered by skin, although some paleontologists argue that they were buried in the body. Its skull was long and narrow, similar to that of a modern crocodile.
Biologically, Spinosaurus had a snout like a crocodile, which would indicate that it ate fish almost exclusively. A 2009 X-ray computed tomography study of one skull indicated that Spinosaurus had pressure receptors inside its skull that allowed it to detect swimming prey without seeing them. The following year, an isotope analysis of Spinosaurus teeth indicated the animal spent most of its life in the water. However, biomechanical stress data show that Spinosaurus had powerful jaw muscles, and its teeth and jaw were structurally very strong. Thus, Spinosaurus is not precluded from being a land predator which could bite through muscle and cartilage, perhaps even bone. A problem for Spinosaurus is that theropod (carnivorous) dinosaurs lacked the ability to rotate their hands. Spinosaurus's hands -- whatever they looked like, and whatever their size -- probably were little different from that of a T. rex or Allosaur. The back feet, however, seem to have been at least partially webbed. Furthermore, an emerging majority of paleontologists believe that Spinosaurus legs were a little shorter than usual. This indicates that the animal probably walked bent over in the water, it's snout above or just on the surface. It would move about by "punting" (not swimming so much, as gliding like a hippo), seeking prey and snapping quickly.
If these hypotheses are true, then on land Spinosaurus would have waddled more than ran. It would not have been the swift, running, powerful hunter depicted in Jurassic Park III but rather an ambush predator which lay in with in the shallows or on the bank.
Although most of this research has come out since Jurassic Park III, there was a good case to be made for a Spinosaur as a fish-eater, not a T. rex killing machine. So it's no wonder that Steven Spielberg drew some heavy criticism for depicting the animal incorrectly, and for killing of T. rex.