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The Tyrannosaurus rex had titanic proportions, just like many other dinosaurs hundreds of millions of years ago.

Currently, the largest specimen ever found is “Scotty,” whose fossilized remains were discovered in Saskatchewan, Canada in 1991. Paleontologists estimate that the carnivorous dino weighed more than 19,000 pounds, or nearly nine tons, at the time of its death.

But scientists are still wondering what if there were larger T. rexes yet to be found.

That’s what paleobiologists Jordan Mallon and David Hone showed in their research paper published in Ecology and Evolution recently. The duo wanted to approximate how likely it is to discover fossils representing the largest size extremes.

“Our study suggests that, for big fossil animals like T. rex, we really have no idea from the fossil record about the absolute sizes they might have reached,” Mallon said.

The team used computer modeling to estimate the potential maximum size of the T. rex. Their model generated 140 million virtual T. rex individuals, while also factoring variables such as population size, growth rate and incompleteness of the fossil record.

They also used the American alligator as a reference, due to its size and evolutionary relationship to dinosaurs.

The findings showed that the largest possible species could have been 70 percent heavier than the Scotty – weighing about 33,000 pounds. The model suggests that Scotty belonged to individual dinos in the 99th percentile.

However, finding specimens in the 99.99th percentile – essentially the largest possible individuals – could take millennia at the current rate of fossil discovery.

So far, paleontologists have only found 84 reasonably complete skeletons, but it is estimated that 2.5 billion T. rexes lived over the species’ 2.4 million-year existence, according to Science Alert.

The authors also acknowledged challenges in the research, such as using the alligator species as a reference.

They highlighted the importance of using statistically controlled parameters rather than relying solely on the largest known specimens when comparing the body sizes of fossil species.

“Arguing about ‘which is the biggest?’ based on a handful of skeletons really isn’t very meaningful,” explained Hone. “It’s important to stress that this isn’t really about T. rex … but this issue would apply to all dinosaurs, and lots of other fossil species.”