The Tyrannosaurus Rex ruled the forested valleys of North America around 65-70 million years ago (until the Cretaceous-Tertiary mass extinction which coincided with the impact of the Chicxulub asteroid which left a 180 kilometre / 111 mile wide crater that was discovered beneath the Yucatan Peninsula in Mexico during the 1970’s). In Greek Tyrannosaurus means “Tyrant Lizard” and Rex means “King“. Although not the only predator of this period it is certainly the most well-known.
Being up to 6 metres (20 feet) tall and 12 metres (40 feet) long and weighing up to 6.5 tonnes these meat-eating dinosaurs are believed to have had a strong sense of smell, powerful legs, a strong tail, strong neck and they could crush and break bones with their huge serrated teeth and powerful bite (the equivalent of 2,267 kg / 5000 pounds of downward pressure). With each bite they could consume 230 kg / 500 pounds of meat! The T-Rex could live for up to 30 years and truly were a “Tyrant Lizard King“!
The Dinosaur Hall of the Los Angeles County Museum of Natural History in California has a great collection of dinosaur fossils including a unique display on the Tyrannosaurus Rex. They have the skeletons of a 17 year old sub-adult, a 13 year old juvenile and a 2 year old baby T-Rex on display within the hall.
These different fossils demonstrate the dramatic growth and changes in the T-Rex in just a few short years. The sub-adult fossil is 10.3 metres / 34 foot long, the juvenile 6.1 metres / 20 feet long and the baby 3.3 metres / 11 foot long! You will not see this type of exhibit anywhere else in the world and the baby T-Rex is the youngest known T-Rex fossil to ever be found!
This museum is well worth a visit if in Los Angeles (there is a lot more to see besides Dinosaurs) and right next door is the California Science Centre which is also a great museum. So if you have the time take a close up look at a T-Rex and check out those teeth!