Page 145 - Prehistoric Animals

Ty-Ran-O-Sorus

Tyrannosaurus

What is a Dinosaur ?
Known as a Dinosaur

Tyrannosaurus (tyrant lizard King) is a genus of tyrannosaurine
theropod dinosaur. It roamed the planet in the Upper Cretaceous, 68
to 66 million years ago. It measured an estimated 12 metres in length, 3
to 4 metres high at the hip, and weighed in around 10 tonne. The most
popular and only species of the genus Tyrannosaurus is T.Rex (Rex
meaning, king). Its popularity has made the name Tyrannosaurus Rex
almost synonymous when referring to the genus Tyrannosaurus. This
exclusivity enjoyed by T.Rex is being questioned as new evidence sug-
gests there are specimens of T.Rex that are in fact species in their own
right and should be acknowledged as such within the genus Tyranno-
saurus*.

Tyrannosaurus was big. Its size has earned it the status as the
larges bipedal carnivore to have roamed the Americas in the Creta-
ceous period. It also had a huge head measuring over a metre long that
narrowed at the snout. The teeth lining its powerful jaws were big,
sharp and deadly; with the longest, large curved ripping teeth, lining
the upper jaw. One of these teeth found, with its root, was an estimated
12 inches long. To support its massive bulk Tyrannosaurus had two
long thick but muscular legs with massive three toed feet. With this
heavy body and hefty legs, it’s thought unlikely Tyrannosaurus could
run, and was possibly restricted to a ponderous but hurried striding
pace. Its muscular forelimbs or arms were short, with two clawed fin-
gered hands. Like its Asian counterpart, Tarbosaurus Bataar, (see
Page 132), what these short arms were used for is a bit of a mystery.
However, many believe, as with its Asian counterpart, there small size,
at least, was all about keeping a balance between its huge head and
heavy tail.

Since Henry Fairfield Osborn named, Tyrannosaurus, in 1905,
T.rex’s depiction as a wide jawed rampaging beastie, fighting and de-
vouring everything in sight has made it one of the world’s best known
theropod dinosaurs. However, most of what is known about Tyranno-
saurus is speculative based on how the animal is perceived to have
looked and behaved. Very little is known about what it ate, or how it
lived and hunted. Many believe it was an apex predator and very suc-
cessful, while others, citing its lack of speed, claim it was a scavenger,
living on the leftovers of other predators or dead bodies it stumbled
across. However, evidence of its bite marks found on fossils of its own
kind does suggest it dabbled in cannibalism. Whatever the truth is
about this huge impressive creature disappeared along with the animal
itself in an event which drove it into extinction. An event, like Tyranno-
saurus behaviour and life style, that is still unclear and still subject to
debate.
*Two of the disputed species, T. imperator, and T. regina