Towering above you is a cast of the fossil skeleton of a giant two-legged meat-eating dinosaur called Giganotosaurus carolinii. Its name means ‘Giant Southern Lizard’ and it roamed Argentina, possibly in family groups, 112–89 million years ago in the Cretaceous period. When Giganotosaurus was discovered in 1995 it was assessed as being even bigger than T.rex , although its exact size is difficult to determine as the fossil remains are not complete.. Giganotosaurus is estimated as being about 13-15metres long, and about 3.5 to 4 metres tall at the hip. It walked on 2 legs, and had two short front limbs or arms.
This dinosaur is twice as big Muttaburrasaurus. We’ll start at the head on the left and move along the S-shaped backbone to the tail. The neck is as long as the head and consists of 8 neck vertebrae, the undersides of which form an upside down V. Just before the shoulder bones, the vertebrae gradually change to become thicker with rectangular upper plates on top. By the time the vertebrae reach the ribs, they are each the size of medium saucepans. The pelvis has huge bones pointing forward and back, the first looks like an anchor on a boat. Moving further to the right, the tail vertebrae with their single hanging bones below, taper from being the size of a forearm to ending in a point.
The head is around 1.6 metres long, about the size of an average Australian woman. There is a bony crest or ridge on the top of the skull above the eyes. Narrow and long, pointed teeth, around 10-15 cm in length, have serrated edges like a bread knife to help cut through flesh and bone. Giganotosaurus may have been able to hunt even large sauropods using a ‘bite and slice’ technique.
The front limbs or arms are small attach to shield-shaped bones (the shoulder blades) at the shoulder
A single-boned upper arm, the humerus attaches to a double-boned lower arm. The hands each have 3 long triple-jointed fingers with a sharp curved claw on each.
In contrast to the small front limbs, the back legs are large and powerful, the upper and lower legs each as big as a child, around a metre in length. There are four clawed toes on each foot, with the middle claws as long as a bent forearm. The fourth toe (and claw) is at the back of the foot and doesn’t reach the ground – it is a bit like the dew claw on dogs.
The thin, pointed tail may have provided balance and the ability to make quick turns while running. Even though huge, Giganotosaurus may have been fairly agile.
Based on comparisons with living animals, if Giganotosaurus was warm-blooded it would have eaten about 200kgs of food a day. By comparison an adult lion eats only 7kgs a day. This daily food intake would have had to come out eventually. At the other end, it probably did a daily total of 35kgs of poo.