T. rex could have been 70% bigger than fossils suggest, new study shows

There's no denying that Tyrannosaurus rex was one of the biggest and baddest dinosaurs to ever walk the planet. But exactly how big could this ferocious dinosaur get? In a new investigation, researchers attempted to answer that question.

Paleontologists from the Canadian Museum of Nature in Ottawa, Ontario, estimated that the largest T. rex may have tipped the scales at a whopping 33,000 pounds (15,000 kilograms), making it heavier than an average school bus, which weighs about 24,000 pounds (11,000 kg). 

The study was peer reviewed and published July 24 in the journal Ecology and Evolution. 

Currently, the heftiest T. rex on record is a specimen nicknamed "Scotty," which weighed 19,555 pounds (8,870 kg) when it was alive — about as much as 6.5 Volkswagen Beetles. 

According to the new research, the largest T. rex "would have been about 70% bigger" than Scotty, said study co-author Jordan Mallon, a research scientist and head of palaeobiology at the Canadian Museum of Nature. "That almost doubles the size of T. rex," Mallon told Live Science.

To reach this weighty conclusion, the scientists first examined the fossil record, which shows that approximately 2.5 billion T. rexes once lived on Earth. However, only a small fraction — just 32 adult fossils — have ever been discovered, giving the scientists a limited amount of information to pull from.  

Related: ‘Bold theory’ that Tyrannosaurus rex is 3 species gets stomped to pieces