Tyrannosaurus Rex - Meaning : Tyrant Lizard

A female T Rex would spend sometimes nearly a week vocalising her mating call until a male T Rex would hear her. Because of the difference in size, the female is somewhat larger than the male, the male would approach the female with caution in case she attacked him.

A male would make his way to the mating place of the female, usually with a kill he had made on the way. The kill would not be eaten by the male, but offered as a gift to the female which would most often keep the peace initially between them on first encounter. The female would spend time feasting on her gift, the male watching at a distance, still appearing cautious. When the female had had her fill, the male would eat his share of the remaining prey.

Fossil discoveries of the Tyrannosaurus Rex indicate that this species of dinosaur had a large range and lived in low population density. After mating with the male for the first time, they would stay together for a short time mating several times to ensure fertilisation of the female.

The female T Rex would build her large nest from foliage on the ground in which to lay her eggs. Because dinosaurs laid their eggs on the ground in nests, the nests were often subject to raids from marsupials such as the Didelphodon which was a small scavenging mammal who specialized in raiding abandoned dinosaur nests. Even if the nests had not been abandoned, the Didelphodon would attempt to scavenge the eggs and more than often, the returning female would roar at the scavenger to frighten them off and as they were small and quick, rarely became the dinosaurs meal.

After about three days of mating, the female T Rex would grow tired of her mate and would usually turn aggressive towards him, roaring and growling at him to send him away. The male would reluctantly turn away and leave, he knew better than to stay and as females are larger and more aggressive than the males, if he had tried to remain with the female, he could well have ended up being attacked and become a meal for the female.

After a few months, the female laid her eggs in her large nest and during the 2 months incubation of the eggs, she would not leave the nest, guarding it closely and protecting the eggs from predators. During this time, she would not even eat as she knew the nest was a magnet to scavengers.

When the eggs hatch, the chicks would stay sheltered in nearby bushes while the mother T Rex would break her fast, and go in search of food for herself and her chicks. At around 4 weeks old, the chicks were already standing 1 metre high. They would remain with their mother for protection and feeding for at least the following 2 months. After this time, the mother would abandon them or worse, view them as food.

It was very common for there to be sibling rivalry between the chicks and most often there were outcasts. The ignored chick or chicks usually did not survive for very long and were eaten by predators or killed by their siblings.