2. When people hear the word tyrannosaur, they think of the Tyrannosaurus rex. But, there were many other kinds. Who and what were they? The tyrannosaurs… Were big. Were bipedal. (walked on two legs) Were carnivores. Had big and powerful legs and bodies. Had big heads with lots of long, sharp, and deadly teeth. Had very tiny arms. Were theropods, just like the raptors, ornithomimids, and therizinosaurs. Of course, there were some exceptions to these rules.

3. Tyrannosaur fossils have been found on three continents.

4. Tyrannosaurs walked the earth from 160 million years ago, to the K/T Extinction Event, 65 million years ago. The oldest tyrannosaurs lived during the Jurassic period, though there weren’t many of them and they weren’t very big. In fact, an early tyrannosaur, the Guanlong, was the size of a raptor. The tyrannosaurs became the big and scary carnivores we know and love during the Cretaceous period.

6. The Guanlong (clown dragon) is one of the oldest and smallest tyrannosaurs to be discovered. The Guanlong (clown dragon) is one of the oldest and smallest tyrannosaurs to be discovered. It lived 160 million years ago during the Jurassic period. It lived 160 million years ago during the Jurassic period. It was 10 feet (3 meters) long and weighed between 100 and 200 pounds. It was 10 feet (3 meters) long and weighed between 100 and 200 pounds. The Guanlong doesn’t look much like a typical tyrannosaur. With its crest, it kind of looks like a hadrosaur. But, the shape of its teeth and pelvis clearly classify it as a tyrannosaur. The Guanlong doesn’t look much like a typical tyrannosaur. With its crest, it kind of looks like a hadrosaur. But, the shape of its teeth and pelvis clearly classify it as a tyrannosaur.

8. It measured 30 feet (9 meters) long and weighed around 1 or 2 tons. It measured 30 feet (9 meters) long and weighed around 1 or 2 tons. This tyrannosaur was discovered in China. This tyrannosaur was discovered in China. After investigating trace fossils that show feather imprints, scientists realized that the Yutyrannus is the biggest dinosaur to have feathers. After investigating trace fossils that show feather imprints, scientists realized that the Yutyrannus is the biggest dinosaur to have feathers. Their feathers were soft like baby chicks, leading the scientists to infer they were unable to fly. Their feathers were soft like baby chicks, leading the scientists to infer they were unable to fly. The Yutyrannus (feathered tyrant) lived about 130 million years ago The Yutyrannus (feathered tyrant) lived about 130 million years ago.

9. Like its close cousin, the Tyrannosaurus Rex, the Daspletosaurus was at the top of its food chain. Like its close cousin, the Tyrannosaurus Rex, the Daspletosaurus was at the top of its food chain. Its large size, incredibly strong jaw filled with long sharp teeth, and muscular body made it a terror to many herbivorous dinosaurs living at the same time as the Daspletosaurus. Its large size, incredibly strong jaw filled with long sharp teeth, and muscular body made it a terror to many herbivorous dinosaurs living at the same time as the Daspletosaurus. The Daspletosaurus (frightful lizard) was about 30 feet (9 meters) long and weighed approximately 3 tons. The Daspletosaurus (frightful lizard) was about 30 feet (9 meters) long and weighed approximately 3 tons. It lived in the Cretaceous period, around 75 million years ago. It lived in the Cretaceous period, around 75 million years ago.

11. Paleontologists have had an easier time studying the Gorgosaurus than other tyrannosaurs because so many of its fossils have been found. The Gorgosaurus (fierce lizard) was about 30 feet (9 meters) long and weighed between 2 and 3 tons. It lived around 75 million years ago during the Cretaceous period.

12. The Appalachiosaurus (Appalachia lizard) was discovered in Alabama, in the south eastern U.S. The Appalachiosaurus (Appalachia lizard) was discovered in Alabama, in the south eastern U.S. Scientists believe it was 25 feet (7.6 meters) long and weighed about 2 tons. Scientists believe it was 25 feet (7.6 meters) long and weighed about 2 tons. A unique characteristic it had were six crests on its snout. An interesting fact scientists learned from one of its fossils is, that it has bite marks from a Deinosuchus, a pre-historic crocodile!

13. TARBOSAURUS The Tarbosaurus (terrifying lizard) was 40 feet (12 meters) long and weighed 5 tons. It lived during the Cretaceous period around 70 million years ago. When it was first discovered in Asia, scientists thought it might have been a T-rex because they look so similar When it was first discovered in Asia, scientists thought it might have been a T-rex because they look so similar. Shorter arms and different jaws distinguish it from the T-rex. Paleontologists have discovered bite marks on a Parasaurolophus consistent with a Tarbosaurus’ bite marks, indicating the Tarbosaurus was a scavenger. Parasaurolophus

14. ALBERTOSAURUS The Albertosaurus (Alberta lizard) lived about 75 million years ago on North America. It was about 30 feet long (9 meters) and weighed 3 tons. Its diet was probably dominated by the hadrosaurs, the duck- billed dinosaurs. Unfortunately for the hadrosaurs (and many other smaller creatures), scientists think the Albertosaurus might have hunted in packs.

15. TYRANNOSAURUS REX Weighing in at 7 tons and measuring 40 feet (12 meters) long, the T-rex is the undisputed heavy weight carnivore of the world. The Tyrant Lizard King Scientists are unsure if it was a predator, scavenger, or both. Sharp teeth and big strong bodies are very useful tools if you are going to be a predator. The T-rex had many sharp teeth and an enormous body, leading scientists to think it was a predator. Though, how it got its meat is in dispute.

16. TYRANNOSAURUS REX So why do paleontologists think it might have been a scavenger? 1. Their eyes were small and weak. Predators usually have very good eyesight. 2. Unlike in the movies, they were not very fast. This would have made it difficult for them to catch their prey. 3. Their extremely short arms would have been useless to a predator on the attack. 4. They had very big olfactory lobes (areas in their brain used for smell). This would have been very helpful to a scavenger seeking out carrion 4. They had very big olfactory lobes (areas in their brain used for smell). This would have been very helpful to a scavenger seeking out carrion.

17. TYRANNOSAURUS REX Here are some interesting facts about the mighty T-rex, you might not have known Based on the fossils they have found, the females were probably bigger than the males. It most likely had horrible breath. Its large and sharp teeth were not good at grinding up its food before swallowing. Some of the meat would have got stuck in its numerous teeth and rotted, causing a horrendous stench! Some paleontologists believe baby T- rexes were covered in feathers. Just like birds. They lived to be about 30 years old. Even though the dinosaurs were reptiles, and reptiles are cold- blooded, the T-rex (and many other dinosaurs) could have been warm- blooded.

18. THE GUANLONG MYSTERY WHEN SCIENTISTS FIRST DISCOVERED THE GUANLONG, THEY FOUND TWO DIFFERENT GUANLONG FOSSILS LYING ON TOP OF EACH OTHER. ONE WAS 7 YEARS OLD WHEN IT DIED AND THE OTHER WAS 12 YEARS OLD WHEN IT DIED. THEY DIED AT DIFFERENT TIMES. THERE AREN’T ANY REASONS TO BELIEVE THEY HAD BEEN FIGHTING OR ATTACKED BEFORE THEY DIED. WHY WERE THEY BURIED TOGETHER? SCIENTISTS DON’T KNOW. WHAT DO YOU THINK HAPPENED?

19. The Guanlong Mystery ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Name________________ Date______________

20. TYRANNOSAURS SCIENTISTS ARE NOT EXACTLY SURE WHY DINOSAURS AS BIG AS THE TYRANNOSAURS WOULD HAVE FEATHERS. THEY WERE TOO BIG TO FLY. BASED ON WHAT YOU KNOW, HOW WOULD YOU EXPLAIN THE PURPOSE OF FEATHERS ON A TYRANNOSAUR? ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Name ______________ Date ______________

21. TYRANNOSAURUS REX PREDATOR OR SCAVENGER

22. TYRANNOSAURUS REX BASED ON WHAT YOU HAVE LEARNED, DO YOU THINK THE TYRANNOSAURUS REX WAS A PREDATOR, SCAVENGER, OR BOTH? EXPLAIN YOUR ANSWER BELOW. ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Name ______________ Date ______________