London, Nov 17 (ANI): A new research has concluded that apart from being the largest predator ever to walk the Earth, Tyrannosaurus Rex was the fastest.
The study dismisses suggestions that the dinosaur was a sluggish scavenger.
The seven ton reptile, which was 13 feet tall and 40 feet long, was able to outpace any prey due to giant muscles located at the top of its tail.
Previously the tail had been thought of merely as a counterbalance to the weight of the beast's giant head.
"Contrary to earlier theories, T-Rex had more than just junk in its trunk," the Telegraph quoted Palaeontologist Scott Persons, of the University of Alberta in Canada, as saying.
He compared the tails of modern-day reptiles like crocodiles and Komodo dragons with that of T Rex, which lived about 65 million years ago, and found the biggest muscles in all of them are attached to upper leg bones.hese 'caudofemoralis' muscles provide the power stroke allowing fast forward movement but Persons discovered one crucial difference in the T Rex structure.
Animal tails get their shape and strength from rib bones attached to the vertebrae. Persons found that the ribs in the tail of T Rex are located much higher up.
That leaves much more room along the lower end for the caudofemoralis muscles to bulk-up and expand. Without rib bones to limit their size, they became a robust power-plant enabling the dinosaur to run.
Persons extensive measurements of T Rex bones and computer modelling shows previous estimates of the muscle mass in the dinosaur's tall were underestimated by as much as 45 per cent.
That led many earlier researchers to believe the animal lacked the necessary muscle mass for running which in turn limited its hunting skills.
That lack of speed cast T Rex in the role of a scavenger only able to survive by feeding on animals killed by other predators.
As for T Rex's exact speed, researchers say that is hard to measure but Persons believes it could run down any other animal in its ecosystem.
The findings have been published in The Anatomical Record. (ANI)