Leading this list of 15 'prehistoric superstars' is the Argentinosaurus. To put its scale into perspective, an adult specimen could weigh between 70 and 100 tonnes—the equivalent of stacking 12 to 15 adult African elephants. With a length of up to 35–40 meters, it could stretch nearly halfway across a professional soccer pitch. Compared to the more famous predators on this list, such as the T-Rex (which weighed only about 8–9 tonnes), the Argentinosaurus was a 'gentle super-heavy tank' of biological evolution. These massive titanosaurians dominated the South American landscape during the Late Cretaceous, pushing the theoretical size limits of terrestrial vertebrates through highly efficient metabolism and specialized respiratory systems.