London, Oct 1 (IANS) Dinosaurs have just got a little bit scarier in terms of size.
The pre-historic giants were even bigger than the skeletons displayed in museums, with scientists underestimating their size.
The study suggests the creatures had thick layers of cartilage in their joints, making the gaps between their bones larger.
The difference is greatest in lumbering plant eaters such as Brachiosaurus, which, thanks to the research, has grown more than 12 inches to tower at 43 feet.
T-Rex and Allosaurus, two of the fiercest hunters to roam earth, were 'several inches' bigger, reports the Daily Mail.
The findings also mean that some species had even more powerful legs and arms than previously thought, and were even quicker at sprinting after prey.
Casey Holliday of the Missouri University and colleagues in the US made the discovery after analysing the bone structures of ostriches and alligators - the two closest modern relatives of dinosaurs - and comparing these with the leg bones of the T-Rex, Allosaurus, Brachiosaurus.
Co-author Lawrence Witmer said: 'This study is significant because it shows that bones can't always speak for themselves.'
His team tested the limbs of some of dinosaurs' modern relatives, ostriches and alligators, to estimate how much cartilage their ancient ancestors might have had.
Bones stripped of cartilage were four percent to nearly 10 percent smaller, and each contained some characteristics similar to dinosaur bones that can create a cartilage signature.
Using that information, he calculated that certain dinosaurs would have had more cartilage than others - enough that already huge sauropods like Brachiosaurus could have added another 12 inches of height.