The question of how large the Tyrannosaurus rex truly was has intrigued scientists and enthusiasts alike. Recent studies suggest that this iconic dinosaur may have been larger than fossil evidence implies, even if it was not the largest of the theropod predators.
According to paleontological research, a typical T. rex could reach lengths of approximately 40 feet and stand about 13 feet tall. These dimensions are derived from the fossils that have been discovered, allowing researchers to estimate the average size of this dinosaur. However, there is a possibility that individuals may have grown even larger.
While the T. rex is among the most well-known dinosaurs, it is not the largest theropod predator. Dinosaurs such as Spinosaurus, Carcharodontosaurus, and Giganotosaurus are believed to have surpassed it in size. The fossil record indicates that T. rex reached lengths of up to 40 feet and could weigh as much as 7 tons, but some researchers argue that these figures may be just the beginning of what could be discovered about the largest T. rex specimens.
Dr. Jordan Mallon, a paleontologist at the Canadian Museum of Nature, points out that an estimated 2 billion T. rex individuals lived during the Late Cretaceous period, with roughly 20,000 adults alive at any given time. This staggering number highlights the scarcity of fossil remains, with only 30 to 40 known specimens available for study.
In a 2024 paper co-authored by Mallon and David Hone from Queen Mary University of London, it is suggested that T. rex could have potentially weighed 70 percent more than current fossil evidence shows. The study utilized computer modeling to propose that the largest individuals may have weighed up to 15 tons and measured around 50 feet long. Mallon emphasizes that this hypothesis represents an extreme case of size.
This line of research raises questions about whether such a massive dinosaur could have supported its own weight and the ecological ramifications of its size. Mallon notes that the T. rex likely preyed on duck-billed and horned dinosaurs, suggesting that the largest individuals might have been capable of taking down even larger targets, such as sauropods.
However, testing this hypothesis is challenging due to the limitations of the fossil record. Mallon acknowledges that the chances of finding the largest T. rex fossils are very slim, making it unlikely that these specimens will ever be discovered.
Even if a T. rex could have reached lengths of 50 feet, it would still not hold the title of the largest dinosaur, as the enormous sauropods surpassed the sizes of all theropods. For instance, Dreadnoughtus may have reached lengths of around 85 feet and weighed up to 65 tons.
Many other large theropods, including Spinosaurus, which is believed to weigh about 7.4 tons and reach lengths of 45 feet, and Carcharodontosaurus, which is similar in size to T. rex but with a lighter build, also compete for the title of largest theropod.
The scarcity of fossil samples complicates understanding the full range of sizes these dinosaurs could achieve. Mallon argues that while the collection of T. rex remains is relatively good compared to other species, it still represents a mere fraction of those that existed.
In 2008, researchers found ancient proteins in a fossilized T. rex femur, linking it genetically to modern birds like chickens and ostriches, rather than reptiles such as alligators. Mallon clarifies that all birds are descended from dinosaurs, making them distant relatives of T. rex.
As evidence continues to accumulate, the evolutionary connection between birds and dinosaurs becomes increasingly undeniable.
