Name: Tarbosaurus bataar
Name Meaning: Alarming Hero Lizard
First Described: 1955
Described By: Maleev
Classification: Dinosauria, Sauirschia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Tyrannosauroidea, Tyrannosauridae, Tyrannosaurinae,Tarbosaurini
Tarbosaurus is one of those dinosaurs who I bet would constantly be waving their arms around in frustration every time dinosaurs are brought up in discussion. After all, it was extremely similar to Tyrannosaurus rex in appearance and size. In fact, some scientists believe that the two genera are synonymous, making the Tarbosaurus genus redundant (though there is plenty of evidence against this claim, as described below). So why is it not revered as much as Tyrannosaurus rex (which, I would argue, should not be revered as much as it is)? Simple dumb luck. It was not discovered first, and it is not from North America. But that does not mean it is any less deserving of our study and time, and given how much study and time we’ve devoted to Tyrannosaurus, Tarbosaurus has really been cheated. It lived in the Maastrichtian age of the Late Cretaceous, about 70 million years ago, and has been found primarily in Mongolia. Adults were between 10 and 12 meters long and almost 4 meters tall, with skulls up to and over 1.3 meters long, making it slightly smaller than Tyrannosaurus, but still one of the largest tyrannosaurids known.
Alioramus is the closest known relative of Tarbosaurus, and the two share many skull characteristics that are not found in other tyrannosaurs. This contributes to the current argument that Tarbosaurus is not really a species of Tyrannosaurus, given that the two would lack these similar skull features. Lythronax, however, shares similar features to both, and given its earlier position in time brings the two back into closer relationship again. It is known from over 30 specimens, some that are fairly complete and well-preserved; a quarter of all fossils collected from the Nemegt Formation in the Gobi desert belong to Tarbosaurus (You wonder why I’m irritated it hasn’t been studied as much as Tyrannosaurus, this would be why.) Tarbosaurus primarily has been found to have injuries (stress fractures) in its hands, rather than its feet, indicating it often used its hands to grip struggling prey, indicating a very active predation-based diet.
The skull of Tarbosaurus was built to handle stress differently than the skulls of American tyrannosaurids; with the force of the bite being transmitted into the skull bones surrounding the maxilla (the primary tooth bearing bone of the upper jaw), while in North American species, the force went into the nasal bones on the top of the head,w hcih were connected by bony struts not present in Tarbosaurus. This indicates that its upper jaw was on the whole, more rigid; furthermore, it also had a more rigid lower jaw. This rigidity in the skull as a whole indicates that Tarbosaurus was more adapted to hunting the titanosaurid sauropods from the region, which were not as common in North America at the time. Furthermore, the extreme skull differences between Asian and American tyrannosaurids indicates that Tyrannosaurus and Tarbosaurus are actually so similar due to convergent evolution, rather than a close evolutionary relationship. The brains of Tyrannosaurus and Tarbosaurus were mainly similar, with only some differences in cranial nerve root positions.
Most specimens found have been adults or subadults, with rare juvenile skeletons. One found in 2006 was about 2 to 3 years old, with a weaker jaw than the adults, with thinner teeth, indicating a different food preference in juveniles. Tarbosaurus also had a well developed Jacobsen’s organ, which was used to detect pheromones, indicating that Tarbosaurus had complex mating behavior. it also had a large auditory nerve, indicating good hearing, useful for aduitory communication and spatial awareness. Unlike Tyrannosaurus, Tarbosaurus had mainly sideways facing eyes, and a poor optic nerve, making it likely that Tarbosaurus relied more on smell and hearing than on eyesight.
Tarbosaurus lived in a diverse, humid environment, with periodic droughts and large rivers and floodplains. There were also many shallow lakes and mudflats, allowing a large, diverse community to exist in the region. Many species of crocodilians and birds have been found, but not many mammals. Many ankylosaurids such as Tarchia and pachycephalosaurs like Prenocephale lived in the area. Tarbosaurus was the largest carnivore in the region, preying on large hadrosaurs like Saurolophus and Barsboldia and sauropods like Nemegtosaurus and Opisthocoelicaudia. Small theropods in the region such as Alioramus, troodontids, and Bagaraatan would have provided little competition. Therizinosaurus was a herbivore mainly left alone, as were ornithomimosaurus such as Anserimimus, Gallimimus, and Deinocheirus. In all, Tarbosaurus lived in a diverse environment and was an interesting predator, not to be ignored or forgotten.
Also, it probably had feathers, but as you guys should know by now, that’s my position on quite a few dinosaurs (the vast majority).
Shout out goes to wildbonobonights