Vastatosaurus Rex

The Vastatosaurus Rex was an antagonist in King Kong. An evolved descendant of the ancient Tyrannosaurus rex that lived after the Cretaceous, this species was the largest terrestrial predator found on Skull Island, reaching a height of over 22 feet at the hip, measuring over 50 feet long (according to the World of Kong book). The weight of the Vastatosaurus rex probably outclassed its predecessor, Tyrannosaurus rex. Despite their size, they could break into surprising bursts of speed, often achieving speeds of 25 mph over short distances.

Vastatosaurus rex was fictionally hypothesized to be what the Tyrannosaurus rex could have become if it were allowed to evolve unabated after the past 65 million years. Their advancement could be due to the vast abundance of large prey, the rarely changing environment of the lush Skull Island, and warm humid climate similar to the Cretaceous. Like their prehistoric relatives, V. rexes had little competition for their position as top predators.

The Vastatosaurus had d eveloped many unique features over the 65 million year time gap, but they still retained several recognizable similarities to their Cretaceous cousins. Vastatosaurs had large heads that evolved over time to be thicker and bulkier, giving them extra protection, and its overall leather-like hide reduced physical injury from hunting if its choice of prey was smaller than itself. Its gaping mouth was its main tool for hunting, filled with large teeth that were constantly being regrown to replace those lost in conflict. Unlike most theropods, the Vastatosaurus had overlapping peg-like teeth. Their heads were shorter and more compact than that of their ancestors, intensely reinforced with thick bone. As the primary weapon of the animal, an individual Vastatosaurus head was often distinctive, being covered with scars and callouses from rivals. Abnormal bone growths from old battles with prey, other predators, rivals, or even mates were not uncommon. A narrow, short rib cage and a large gap between the ribs and hips allowed V. rexes surprising flexibility for animals of their size, a necessary adaptation to survive amongst the towering trees and broken terrain of Skull Island.

The Vastatosaurus rex had a limited but notable ability to problem solve. The species displayed enough ingenuity to knock down large objects obstructing its path toward smaller prey that tried to conceal themselves between them; if such prey still held its interest, the dinosaur would also try to find ways around obstacles to pursue it. Like early tyrannosaurs, their forelimbs were small in comparison with the rest of their body. One distinctive feature that distinguished them from Tyrannosaurus rex was the additional digit on their forelimbs. Tyrannosaurus rex only had two fingers on their forelimbs, but V. rex had three. The extra digit, though small, acted like a thumb and was useful when dragging dead animals; the tiny arms helped to pin swinging carcasses against the animal's chest for stability. However, they were of no known uses for hunting and were often seen being held tightly against the body. Though these arms look tiny, each arm can lift several hundred pounds apiece, just like those of their ancient tyrannosaur ancestors.

While juvenile V. rexes tended to cluster in the thick jungle interior (occasionally encountering Venatosaurus packs), the large adults hunted mostly in the open areas of the lowlands, where they could move more freely. Large males sought the most open territories, while mature females usually staked claim to areas on the fringes of the forests, where they could find secluded nesting sites. Fiercely territorial, adult V. rexes suffered few rival encroachments on their hunting grounds. Territorial boundaries were regularly marked with urine, and dawn roaring warned other animals in the vicinity that they would not be tolerated. Other predators could detect a lot about the physical condition of the owner from the smell of its urine, and the size of the animal could be determined by the sound of a roar. Displays and scenting minimized potentially dangerous confrontations between animals of different sizes. Occasionally, disputes between evenly matched carnivores could erupt. With the threat of serious injury, these confrontations were usually resolved with intense roaring matches in which each animal tilted toward the ground and bellowed in an attempt to intimidate the other. If this failed, violence ensued. Older V. rexes boar the crisscrossing scars of many such fights. As seen in the movie, the Matriarch was an old grizzled female riddled in savage scars before being killed by Kong along with The Bull and the Juvenile.

Exceptions to their solitary existence were made in the breeding season. Males left their hunting grounds to seek females in season. If the female was receptive, she would accept the mating proposal and the pair may stay together, hunting in the female's territory for several days before she tired of him and sent him on his way. Young V. rexes seeking to hone their hunting skills sometimes followed adults at a safe distance during the mating season, watching and occasionally stealing meals from unguarded kills. Taking advantage of the season of nomadic adult males, bold adolescents might have dared to move in to claim currently undefended territory as their own. V. rexes were capable of tackling very large prey, but their massive size was often employed to intimidate smaller carnivores effectively bullying them from a kill.

V. rex had intensely acidic stomachs, capable of processing even the most rancid rotting meat, a feature that served the species well. Their massive jaws could exert astounding pressure, shattering bones to expose the rich marrow less robust predators were unable to reach.

Despite their excellent ability to scavenge carrion they were very capable hunters capable of tackling virtually anything on Skull Island, though several prey species were more dangerous than others and in such cases less risky prey items were usually chosen over the more dangerous ones. Vastatosaurs tended to employ ambush tactics, using cover in and around waterholes or in forested areas to surprise prey. If the prey escaped and was large enough, Vastatosaurs would tend to follow or tailgate it with an open mouth, eagerly awaiting an opportunity to make the first crippling bite. Ligocristuses were the primary prey of adults, being the most abundant. Ferrucutus and Brontosaurus were more dangerous prospects, although if a young or sick animal could be separated from the protection of the herd, it could have been an easy kill. Smaller species were likely game, though most were too small to provide a sufficient supply of nutrition. The greatest challenge for such a large animal was concealment.

Full grown Vastatosaurus were dark blueish-black in color and, despite their size, could be surprisingly stealthy, using scrubland and unstable ruins for cover. Their dark scales also helped them warm up quickly at dawn, boosting their energy levels to gain an advantage over still sluggish herbivores. The V.rex was unquestionably the most formidable predator on the island. With its crocodillan-like skin, huge jaws, gargantuan size and surprising speed, it seemed very unlikely that any creature outside of another of their own kind was capable of taking an adult down, Megaprimatus kong being the only known exception (and possibly bull Ferrucutus). Note also that young V.rex were highly vulnerable particularly to Venatosaurus packs.