Tyrannosaurus Rex
Scientific Classification:
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: Tyrannosauridae
Subfamily: Tyrannosaurinae
Genus: Tyrannosaurus
Type Species: Tyrannosaurus Rex
Meaning "Tyrant Lizard King."
Described by Henry Fairfield Osborn, 1905
Common Names: T. Rex, Tyrannosaurus, Rex, Rexes, Tyrannosaurs, and T-Rex.
Current Park Population: 4 (2 adults, 1 Male and 1 Female, and 2 juveniles, 1 male and 1 female).
Park Diet: pre-killed cattle and meat slabs.
Natural Diet: Hadrosaurs, ceratopsians, ornithomimus, Pachycephalosaurs, possibly young sauropods, and occasionally cannibalistic preying on others of their kind.
Lifespan: 28 Years Maximum.
Habitat: Open: Subtropical Forest and Swamp floodplains with large amounts of food and water supplies
Native Ecosystem: Western North America, on what was then an island continent known as Laramidia. Hell Creek Formation, Lance Formation, Willow Creek Formation, Montana, South Dakota, Wyoming, Alberta, Saskatchewan, and possibly New Mexico and Texas, 68-66 Million Years Ago, Maastrichtian Stage.
Breeding Season: Year-round.
Gestation Period: Four to six months.
Eggs Laid: One to five, occasionally six, depends on the food supply.
Hatching Time: One to three weeks, depends on the climate.
Danger Level: Extremely dangerous proceed with extreme caution, 10 out of 10.
Summary: When everyone hears the word dinosaur, most people think of the Tyrannosaurus Rex. Tyrannosaurus Rex is one of the world's most famous dinosaurs, along with Triceratops, Velociraptor, Stegosaurus, Spinosaurus, and Brontosaurus. As the archetypal theropod, Tyrannosaurus has been one of the best-known dinosaurs since the early 20th century and has been featured in film, advertising, postal stamps, and many other media. It was the last known member of the tyrannosaurids and among the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event.
Description: Like other tyrannosaurids, Tyrannosaurus was a bulky bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to its large and powerful hind limbs, the forelimbs of Tyrannosaurus were short but unusually powerful for their size, and they had two clawed digits. They often get scars from battles from their prey and other T. Rexes.
Adults are mostly bare with scaly skin with spare filament bristles on the back of their heads, neck, shoulder and arm regions, back, thigh regions, and tail. They are dark brown with black striping and spotted patterns with striping on the tail, a white underbelly, a mottled face that it black tip at the end of the snout, and a mix of light orange and dark brown stripings, the eyes had a light orange eye ring and black markings surrounding the eyes, thighs of the legs were black striped and bronze-like yellow, the keratin running down its nose, orbital hornlets, and brow, gray jugular horns on the cheeks, and unlike most depictions, the teeth were covered with scaly like lips.
Males have a longer bigger thin black bristle manes, the mottled face is mix of yellow orange and dark brown stripes and blotches, on the sides of the neck have red patches that go down the neck, a red gular sac throat, and it have bumpy keratin running down its nose, orbital hornlets, and brow which was bright orange more pronounced in its large size and horn like and measured up to 10 feet tall and 12.4 meters long.
Females have a short bristle mane, a peach mottled face with dark brown spots and stripes. Measuring up to 12 feet tall and 12 meters long. The keratin running down its nose, orbital hornlets, and brow which was light orange.
Males are larger in weight and length while Females are Taller in height.
Subadults look identical to the adults, but are about 9 feet tall and 8 meters long, their keratin nose, orbital hornlets, brow, and face are light peach and faces, and they have a short mane of light brown proto-feathers on their neck and on the rest of the upper body, all the way to its tail, shoulder region, and arms were thin bristle like filament feathering.
Adolescents resemble the adults in color, but with dark pale faces, thinner muzzles, bronze yellow longer legs, a lighter build, and light brown proto-feather manes on the necks and arms.
Hatchlings are covered in a coat of downy feathering often tan with light brown stripes, a pale mottled face, bronze yellow colored legs, and a black tipped tail.
History of Research:
Earliest Finds: Teeth from what is now documented as a Tyrannosaurus rex were found in 1874 by Arthur Lakes near Golden, Colorado. In the early 1890s, John Bell Hatcher collected postcranial elements in eastern Wyoming. The fossils were believed to be from the large species Ornithomimus grandis (now Deinodon), but are now considered T. rex remains.
In 1892, Edward Drinker Cope found two vertebral fragments of a large dinosaur. Cope believed the fragments belonged to an "agathaumid" (ceratopsid) dinosaur, and named them Manospondylus gigas, meaning "giant porous vertebra", in reference to the numerous openings for blood vessels he found in the bone. The M. gigas remains were, in 1907, identified by Hatcher as those of a theropod rather than a ceratopsid.
Henry Fairfield Osborn recognized the similarity between Manospondylus gigas and T. rex as early as 1917, by which time the second vertebra had been lost. Owing to the fragmentary nature of the Manospondylus vertebrae, Osborn did not synonymize the two genera, instead considering the older genus indeterminate. In June 2000, the Black Hills Institute found around 10% of a Tyrannosaurus skeleton (BHI 6248) at a site that might have been the original M. gigas locality.
Skeleton Discovery and Naming: Barnum Brown, assistant curator of the American Museum of Natural History, found the first partial skeleton of T. rex in eastern Wyoming in 1900. Brown found another partial skeleton in the Hell Creek Formation in Montana in 1902, comprising approximately 34 fossilized bones. Writing at the time Brown said "Quarry No. 1 contains the femur, pubes, humerus, three vertebrae and two undetermined bones of a large Carnivorous Dinosaur not described by Marsh. ... I have never seen anything like it from the Cretaceous". Henry Fairfield Osborn, president of the American Museum of Natural History, named the second skeleton T. rex in 1905. The generic name is derived from the Greek words τύραννος (tyrannos, meaning "tyrant") and σαῦρος (sauros, meaning "lizard"). Osborn used the Latin word rex, meaning "king", for the specific name. The full binomial therefore translates to "tyrant lizard the king" or "King Tyrant Lizard", emphasizing the animal's size and presumed dominance over other species of the time.
Osborn named the other specimen Dynamosaurus imperiosus in a paper in 1905. In 1906, Osborn recognized that the two skeletons were from the same species and selected Tyrannosaurus as the preferred name. The original Dynamosaurus material resides in the collections of the Natural History Museum, London. In 1941, the T. rex type specimen was sold to the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania, for $7,000. Dynamosaurus would later be honored by the 2018 description of another species of tyrannosaurid by Andrew McDonald and colleagues, Dynamoterror dynastes, whose name was chosen in reference to the 1905 name, as it had been a "childhood favorite" of McDonald's.
From the 1910s through the end of the 1950s, Barnum's discoveries remained the only specimens of Tyrannosaurus, as the Great Depression and wars kept many paleontologists out of the field.
Diet: Tyrannosaurus Rex were found all around North America and were the apex predators of their time controlling the populations of Herbivores of their environment preying upon hadrosaurs (Edmontosaurus), armored herbivores like ceratopsians (Triceratops and Torosaurus), and ankylosaurs (Ankylosaurus and Denversaurus), and possibly sauropods (Alamosaurus).
Most paleontologists accept that Tyrannosaurus was both an active predator and a scavenger like most large carnivores scavenging carcasses.
The young are precocial, with their parents only there to protect them and guide them to learn to hunt by chasing small animals and dinosaurs including sea turtle hatchlings along the coast and duck their heads underwater in order to catch fish in wetlands.
Adult Tyrannosaurus would occasionally cannibalize younger Tyrannosaurus that weren't related to them.
Family Lifestyle: Tyrannosaurus Rex lived alone or in loosely formed family packs led by a Mater pair and their offspring. Subadults who are kicked out or leave their family groups form loosely-knitted sibling groups before parting ways.
The Parents and older offspring take care and look after their offspring from other predators and guide them to food.
Communication: Most Depictions show T. Rex roaring like how mammals roar like Lions and bears which is false. Later Research and Observations have shown they make rumbles and bellows instead.
The tyrannosaurs initially assume low postures and open-mouth bellowing in aggressive confrontation.
They mostly communicate by closed-mouth bellowing which can be heard from miles.
Feeding Strategies: Most paleontologists accept that Tyrannosaurus was both an active predator and a scavenger like most large carnivores. Tyrannosaurus had multiple weapons in its arsenal that it could use: its teeth, its tail, their giant foot claws, and the head which could be used as a devastating battering ram. Their eyes can see in binocular vision like hawks, which means unlike some movie, if you stand still it won't see which is due to the frog gene you're still gonna get eaten. Their teeth were the size and shape of a banana and they could use their great bellow roars to disorientate close by creatures, prey or predator.
When hunting the younger adolescents and subadults being slender and agile drive the prey they separate to an ambush site where the bulky adults hide before they attack.
A study in 2012 by Karl Bates and Peter Falkingham found that Tyrannosaurus had the most powerful bite of any terrestrial animal that has ever lived, finding an adult Tyrannosaurus could have exerted 35,000 to 57,000 N (7,868 to 12,814 lbf) of force in the back teeth. This allowed it to crush bones during repetitive biting and fully consume the carcasses of large dinosaurs. Stephan Lautenschlager and colleagues calculated that Tyrannosaurus was capable of a maximum jaw gape of around 80 degrees, a necessary adaptation for a wide range of jaw angles to power the creature's strong bite.
Tyrannosaurus Rex had small arms in dinosaur standards, but that is because they evolved to have a devastating bone-crunching bite. If Tyrannosaurs had survived past the Cretaceous extinction event and the volcanic atmosphere that was killing the dinosaurs off before the asteroid hit, they might have lost their arms all together. Despite their arms being relatively small, they were still powerful and were the size of an adult human's arm.
Paleontologist Kevin Padian argued that the reduction of the arms in tyrannosaurids did not serve a particular function but was a secondary adaptation, stating that as tyrannosaurids developed larger and more powerful skulls and jaws, the arms got smaller to avoid being bitten or torn by other individuals, particularly during group feedings.
Another possibility is that the forelimbs held struggling prey while it was killed by the tyrannosaur's enormous jaws. This hypothesis may be supported by biomechanical analysis. T. rex forelimb bones exhibit extremely thick cortical bone, which has been interpreted as evidence that they were developed to withstand heavy loads. The biceps brachii muscle of an adult T. rex was capable of lifting 199 kilograms (439 lb) by itself; other muscles such as the brachialis would work along with the biceps to make elbow flexion even more powerful.
Extinction: Despite popular belief, it wasn't the singular large asteroid that killed Tyrannosaurus Rex and the rest of the dinosaur dynasty. The large asteroid carried a gravitational field of its own and picked smaller asteroids, comets, and meteors in it while it headed in the direction of earth. With the sun blocked off causing plants to die off leading to die off of herbivores, it would be a feast for predators like T. Rex, but eventually they will starve themselves into extinction.
Danger Tip: Tyrannosaurus are an aggressive species. Good news: they won't attack for no reason. Bad news: they don't need much of a reason. All you have to do is get into their personal space or look them directly in the eye and you can find yourself on the wrong side of a Tyrannosaur's mouth.
Interactions with other species: Herbivores like Triceratops, Torosaurus, Ankylosaurus, Edmontosaurus, Pachycephalosaurus, and many others were prey to T. Rex had to evolved defenses whether be horns, frills, osteoderm armor, clubtails, dome heads, long tails, and living in herds to protect themselves from T. Rex.
One Interesting Observation made by the Rescue Team when they observe that Trierarchuncus, a species of Alvarezsaurs, often hang out near Tyrannosaurs they provide a service by cleaning the T. Rex's teeth by feasting on bits of meat scraps stuck between the teeth for protein supplement like how some birds and fish are cleaning teeth of carnivores like sharks and crocodiles.
Significant events: A Pack of Four T. Rexes was rescued during the Park's First mission and among the last to be rescued. The Rescue Team encountered a trio of subadults after they tried to capture an Ornithomimus from the flock, but managed to escape them. The Next day, the team stumbles upon their territory littered with bones, a sleeping breeding pair, and roughhousing subadults; they stay hidden as the pack departs. The Next Day, the same pack attacks the mixed-species herd of herbivores gathering around a creek after most of the dinosaurs ran off. They turned their attention to a lone Alamosaurus and were very desperate to take this one down. They would later be scared off by the portal when the Team decides to rescue the Sauropod.
The Team also observed an Adult Female joining a hunt only to be injured by the thigh from a mother Triceratops when she grabs a baby in her jaws. The Team decided to track her during that time, Charlie's Group had a dangerous encounter with a large male who gave Numbuh 4 wedgies as it shook the Aussie boy around. It later tried to attack Charlie who hid in a log alongside a Dromaeosaurus and a Dinilysia snake, but managed to escape. The Female was the one observed with the Trierarchuncus cleaning its teeth and was later found near a river washing its wounds in the water. It found a washed up dead Triceratops, but was unable to reach it and was taken over by a flock of Quetzalcoatlus. The Female was seen again chasing a Mixed-Species herd of Herbivore Dinosaurs managing to snatch a weak Ornithomimus lagging behind. The Rescue Team found out the female was a mother of two adolescents in a cave, but a rival male, a threat to her and her babies, challenged her leaving the female very badly wounded. It wasn't until the arrival of the same male showed up to fight off and drive the rival away, it turns out this was the female's mate and father of adolescents. They would later be rescued when the Meteorite strikes the earth and just in time before they were hit by the wave of ash cloud and debris. They now reside in T. Rex Kingdom of the Hell Creek Section of Paleo Park.
T. Rex Kingdom: A large paddock and was mostly covered with forests with few open clearings and waterways to replicate the Hell Creek Floodplain environment. They have a large hill they can walk up and look around from the top view. They normally fed with pre-killed cows left out in the clearing or fed by a feeding crane. It mostly has elevated moats in the surrounding areas, steel bar fencing in the holding areas, and a viewing area which is wooden pole fencing with the moat hidden by plants on the top edge. There is a large steel bar fencing in an elevated deep moat ravine that separates the T. Rex from the other herbivores in the Hell Creek Multi-Species Paddock which is hidden to give the illusion these dinosaurs are in the same space.
Notable Individuals:
Tyrannor: An Adult Male named after the character from Dink, the Little Dinosaur. He is a caring father and mate to Rexy and their offspring.
Rexy: An Adult Female named after the Iconic T. Rex from Jurassic Park and Night at the Museum. She is a caring mother and mate to Tyrannor and their offspring. She is taller in height than Tyrannor.
Matilda: A young female and older sister of Terrence.
Terrence: A young male and younger brother of Matilda. He forms a bond with Thomas Tran.
Conclusion: Paleo Park's pack may be dangerous, but are truly a sight to behold. When they bellow roar, it sounds like the very earth is roaring, and they are extremely protective parents. As long as they are in a visitor safe and proper environment, they will be available for the world to wonder at for generations.
The Field Guide might take a long time, like structuring and writing descriptions of the creatures, but also my time in college and spending time with my family. So you can suggest additional information quotes, descriptions, and natural or speculative behaviors for the prehistoric animals that I can make edits and you send your suggestions either in reviews or Private Messages.
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