Tyrannosaurs, or to be more precise, the theropod dinosaurs that make up the Tyrannosauroid family, are perhaps the best known of all the different types of dinosaurs. One of the last, and one of the largest tyrannosaurs to evolve, was the fearsome Tyrannosaurus Rex (Tyrant Lizard King). This dinosaur held the record for being the largest and most powerful land predator of all time for the better part of a century, no respectable dinosaur movie was complete without a T. Rex or two showing up to chase down and consume a few people. T. rex lived at the end of the Cretaceous, in a part of the world we now know as the western United States and Canada, though at the time much of the Americas was covered by a warm, shallow sea scientists call the Interior. Western. Seaway.
Tyrannosaurus Rex was large with a very deep and powerful skull. Its strong jaws and banana-sized teeth gave it perhaps the most powerful bite of any land predator. Scientists have estimated that it could generate a biting force at the tips of its massive teeth of more than 15,000 pounds per square inch. This is becoming fifteen times more powerful than the bite of a modern African lion (Panthero leo).
However, in the late 1990s, evidence of even larger meat-eating dinosaurs began to be discovered. Scientists had speculated that spinosaurs, particularly the remains of one such creature whose fossilized bones were found in 1911, just a few years after T. Rex was formally named and described, were at least as big as Tyrannosaurus Rex. Fossils found in South America proved that tyrannosaurs didn’t have everything their way when it came to being big and really ferocious. In 1993, a local fossil collector, Ruben Carolini, found the fossilized remains of a huge meat-eating dinosaur. The subsequent scientific expedition discovered the skull of a meat-eating dinosaur that was larger than any T. Rex skull known at the time. The scientists then found the nearby jawbone of another similar creature that was even larger. From these discoveries, the “giant southern lizard” was described and Giganotosaurus carolini officially became the largest carnivorous dinosaur known from the fossil record and, by default, the largest land carnivore of all time.
However, the debate over which was the largest meat-eating dinosaur is still going on, fueled by more fossil discoveries in the United States, Argentina, and North Africa. An intriguing new field of research may have revealed a trait among tyrannosaurs that until recently had not been considered: that these animals may have been pack hunters.
The behavior of carnivorous dinosaurs was most likely as diverse as that of modern mammalian carnivores. Today, we see social hunters like lions and wolves, as well as predators that tend to be more solitary, like leopards and pumas. In addition, some modern predators, largely considered loners, have a pack form of existence for part of their lives. A female polar bear (currently considered the largest terrestrial carnivore in existence today) will have her cubs with her for a considerable period, although the adult does the hunting. Tigers too, highly regarded as solitary hunters, form packs for part of their lives. Here, the young cubs spend perhaps up to two years with their mother and, as subadults, the siblings will often live as a loose collective for a time, before reaching sexual maturity. The collective noun for a group of tigers is a “tiger ambush”, an apt description considering the ambush tactics most tiger species employ when hunting prey.
It was Professor Phi Currie and colleagues who raised the profile of tyrannosaur pack hunting with a paper published in 2000, detailing a study of an albertosaurus (type of tyrannosaur) bone bed in Canada. The scientific paper was titled “Possible Evidence for Herd Behavior in Tyrannosaurs.” The remains of at least three Albertosaurus were discovered together in a bone bed, these dinosaurs were of different sizes, perhaps they were part of a herd of these dinosaurs that perished together crossing a swollen river, or perhaps the bodies of these animals were deposited in the same river. place many years apart after different floods.
Professor Currie of the University of Alberta and his team speculated that, at least for part of the time, large theropods might have formed herds or family groups. Juveniles may have associated with mature animals in herds and therefore did not compete for food with smaller types of theropods. After a five-year research program, more evidence has been uncovered about the herd behavior of large tyrannosaur species in the Gobi desert. Phil Currie has been at the forefront of this research, working closely with his Chinese museum counterparts, including the Institute of Vertebrate Paleontology and Paleoanthropology. This time, the Tyrannosaurus in question is Tarbosaurus bataar, a close relative of Tyrannosaurus Rex. This Asian tyrannosaurid is the largest known Asian predator with fossils found in China and Mongolia. It was very similar to T. Rex with a slightly narrower snout and smaller teeth. It reached lengths greater than 12 meters and would have weighed around five metric tons.
If tyrannosaurs, including Tyrannosaurus Rex, were pack hunters, then these creatures likely specialized in preying on large herbivores such as ceratopsians (horned dinosaurs) and hadrosaurs (duck-billed dinosaurs). It is not known if these animals remained in family groups for much of their lives. It is also impossible to determine if these creatures had any hunting tactics. Lions have strategies to hunt on the African plains, wolves also adopt a number of tactics to catch animals. It is unknown whether tyrannosaurs were capable of communicating and coordinating attacks with individuals who perhaps had their own specialized roles to play in hunting.
Tyrannosaurs as pack animals would have been truly formidable. This raises the intriguing question of what the collective noun for a herd of tyrannosaurs should be. A collective noun is a word used to describe a collection of creatures, such as a pod of whales, a school of fish, or a pride of lions. What would be a known appropriate collective for a group of theropod dinosaurs? Perhaps we could put forward the proposal that a group of Albertosaurs be called a “raid” of Albertosaurs.
But what about the Tyrannosaurus Rex? What would be the collective noun for a group of these fearsome reptiles, might we suggest a Tyrannosaurus “tyranny” or how about a T. Rexes “rant”?