how are they classified?
Superfamily Tyrannosauroidea, the family Tyrannosauridae, and the subfamily Tyrannosaurinae
Tyrannosaurus
"Tyrannosaurus" is the type genus of the superfamily Tyrannosauroidea, the family Tyrannosauridae, and the subfamily Tyrannosaurinae; in other words it is the standard by which paleontologists decide whether to include other species in the same group.
what time period did the t rex live in Maastrichtian age of the upper Cretaceous period, 68 to 66 million years ago what type of organism was this? It is a genus of coelurosaurian theropod dinosaur, one of the most well-represented of the large theropods
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Tyrannosaurus [SEP] Classification
"Tyrannosaurus" is the type genus of the superfamily Tyrannosauroidea, the family Tyrannosauridae, and the subfamily Tyrannosaurinae; in other words it is the standard by which paleontologists decide whether to include other species in the same group. Other members of the tyrannosaurine subfamily include the North American "Daspletosaurus" and the Asian "Tarbosaurus", both of which have occasionally been synonymized with "Tyrannosaurus". Tyrannosaurids were once commonly thought to be descendants of earlier large theropods such as megalosaurs and carnosaurs, although more recently they were reclassified with the generally smaller coelurosaurs. In 1955, Soviet paleontologist Evgeny Maleev named a new species, "Tyrannosaurus bataar", from Mongolia.