Tyrannosaurus rex, that coolest of all the dinosaurs, may have been even bigger and scarier than originally thought. That’s the conclusion that was recently reached by a team of scientists, who used computer modeling technology to estimate the average body mass of the carnivorous dinosaurs. After digitally “fleshing out” existing T. rex skeletons, the researchers now believe that the reptiles grew twice as fast, and reached adult weights up to 30 percent higher than previously assumed.
Previous attempts at estimating dinosaur body mass have used either scaled-down models, or extrapolations based on living animals that don’t necessarily have the same body layout as dinosaurs. This study, however, used five actual T. rex skeletons as the starting point.
These skeletons were laser-scanned, to produce 3D computer models. Using the relationships of the soft tissues to skeletons in birds and crocodiles as a guide, digital body cross-sections were then created along the length of each skeleton, with a virtual skin overlaid on each one. The mass of each section was then calculated, with empty spaces such as the lungs and mouth cavity not being included in the final figures.
A bit more here Computer modeling suggests Tyrannosaurus rex was much bigger