The organ used for balance indicated that the ferocious killer had excellent equilibrium.
"The inner-ear structure is consistent with a dynamic lifestyle involving rapid tracking movements of the eyes and head," Witmer concluded.
Other scientists at the meeting were puzzled. According to paleontologist Jack Horner of Montana State University, T. rex was rigid from the neck all the way back to the tail.
Horner found evidence for T. rex's stiffness by examining the dinosaur's vertebrae.
Microscopic analysis revealed soft tissue remnants and within it, the nuchal ligament, which provides support for the head and neck. The structure appeared to be very stiff, suggesting "a rigidity that would severely limit vertebral flexion," Horner said.
"I'm not arguing with the information on the ear, but it's really odd that we have an animal that looks like it should be agile but isn't," Horner said.
The cutting-edge technologies used to recover information from bits of T. rex bone and tissue did not solve the long-standing debate whether the ferocious carnivore, which roamed North America 85 million to 65 million years ago, was a top predator or a scavenger.
According to Horner, T. rex's rigidity and its bone-crushing teeth would suggest that the beast was a scavenger.
"If you're killing another animal, you don't need bone-crushing teeth.You just take the meat and go," Horner said.
On the other side, Witmer pointed to the fact that T. rex might have used rapid turning movements of eyes and head to track its prey, supporting the idea of the creature was an ambush predator.
"Whether predator or scavenger, it was the pinnacle of meat eaters," Witmer said.
