1. How Did Dinosaurs Become Extinct
By:Rylan,Ian,Jathen

2. How they became extinct
There are many theories to how the dinosaurs became extinct.Here are someways we thought of.There is asteroids,ice age,big bang,and volcanoes.We think that the asteroid killed all the dinosurs because the explosion was about 10km wide!We think the other theories could be what scientists thought what happened to the extinction of the dinosaurs. The dinosaurs became extinct approximately 65 million years ago!This is when humans weren’t existed!

3. How did the asteroid kill the dinosaurs?
Scientists recently discovered what killed the dinosaurs and made them go extinct. A 10km wide asteroid smashed into the Yucatan peninsula in Mexico causing forest fires,tsunamis that are lots of km high,and a very harsh winter which wiped out the whole population of dinosaurs. All of these disasters also ended up blocking the sun! When the sun got blocked there was no more heat for the dinosaurs to be warm.

4. Who discovered dinosaurs?
The first dinosaur that was described scientifically by William Buckland.He first discovered this dinosaur by a fossil.He was a British fossil hunter and he found a fossil.He named the fossil of the dinosaur the Megalosaurus. The fossils were discovered in 1819 and the dinosaur was named in William Buckland had been a fossil hunter for many years and he said it’s been the best thing he had found!

5. How did the asteroid create
Small rocks started to form together in space. They soon started to form larger and larger.It formed to be 10km wide! A meteorite was created. It started to flame down to the dinosaurs habitat. The dinosaurs were all crushed by the meteorite and killed. Their whole habitat and all their homes were destroyed. There was no more dinosaurs,because they were extinct.

6. Fun Facts About dinosaurs
-The first ever dinosaur was named megalosaurus
-Dinosaurs lived on earth about 65 Million years ago
-People who study dinosaurs are called paleontologist
-The heaviest dinosaur was the brachiosaurus that weighed 80 tonnes
-The smallest dinosaur is the lesothosaurus that ate plants.
-The oldest dinosaur is 230 million years old. The second oldest dinosaur is 228 million years old.

7. More Fun Facts About Dinosaurs
- There are about 700 different species of dinosaurs.
- The fastest dinosaur could run as fast as 60 kilometres an hour!
- The two largest dinosaurs (Brachiosaurus and Apatosaurus) were actually herbivores which meant that they only ate plants.
- Almost all the herbivores (plant eaters) have a weapon to defend themselves unlike the carnivores like the T-rex who has nothing to defend himself with.
- The word dinosaur means “terrible lizard” in Greek.

8. What Other People Think Happened
-Ice Age (people think the dinosaurs could not control the temperature)
-disease (people think that a disease spread throughout the dinosaurs)
-competition between other animals (it is possible dinosaurs fought other animals)
-gradual extinction (dinosaurs could have just died out)
-volcano theory (people think between 63 and 67 million years ago a volcano erupted)

9. Our Theory
We think that the reason the dinosaurs became extinct, is because the asteroid hit the dinosaurs. Then when the asteroid hit it made huge chunks of the earth fly up which then blocks the sun. As we know the sun provides heat which is no longer available, so then everything freezes causing Ice Age. So then when everything freezes the dinosaurs will freeze to death. Our theory is a bit complex adding 3 theories in one big theory. So you know the 3 theories are: Ice Age, Asteroid, and Gradual extinction.

10. Second theory
The next theory is the ice age. The ice age was when the Earth somehow tilted and changes the climate by a lot. The climate changed to over 23.5 degrees. That climate was too cold for the dinosaurs so they started to get colder and eventually died. They had no warmth or anywhere to stay warm in the freezing cold. When the climate changed the dinosaurs would start fighting to get to warm shelter, then eventually killing each other. However the scientists have no proof yet for this theory.

11. How the earth tilted
The Earth’s axis was not 90 degrees to the plane so then it orbits the sun. When the tilt came,it made a huge impact which formed the moon. The tilt brings the sun to the northern hemisphere during summer which makes the solar radiations be much hotter. In the fall,winter and spring the tilt makes the sun go lower so that’s why it is usually darker in those seasons. That means there will be less solar radiation. The three other seasons(fall,winter,spring) makes summer be very hot in our hemisphere. The summer is also very hot because the tilt makes the sun go higher into the sky which makes it hotter. That’s why the summer is very bright because tilt makes the sun go into the sky.

12. Third Theory
The third theory is a disease. It wasn't just one disease but several amounts of diseases bunched up together. Which eventually would have spread to the dinosaurs wiping them out in one big blow. There are more than 100 diseases people can say the dinosaurs got. We think the dinosaurs got around 5 to 7 diseases bunched up. Which made it so lethal to the dinosaurs and if it got to us we would probably not do so well either.

13. More about the diseases
The disease of the dinosaurs is called miliaria. That gave the dinosaurs horrible infections putting their lives in danger. The dinosaurs were very slow breeders so then the population of the dinosaurs would become extinct way faster. Ponair was the one to find out about this theory. He still thinks that there could be many more theories.

14. Fourth Theory
Other people just make it simple to explain, they think the dinosaurs just gradually died away. When people say “ the dinosaurs just died “ they basically mean the dinosaurs had no more source of food and any natural resources. It almost sounds like the meteor theory but their food and any source was no longer providable in a different way. That happened because their source of food started to get lowered from the sun being blocked. Then the plants got no sunlight and the food started to produce less and less. Eventually the food for the dinosaurs will become extinct.

15. Fifth Theory
The fifth theory is that the dinosaurs could have fought each other, or other animals to the death and if that were true the dinosaurs would have died. Then became extinct due to the fights.The dinosaurs got very unfriendly and started to cut each other so bad they would bleed to death! We think that the dinosaurs should have just minded their own business so that there could still be a chance of dinosaurs living, Instead of them fighting and dying.

16. More about the volcano
Some researchers say that the meteor didn’t kill the dinosaurs they think that an active volcano killed them. The researchers say that a volcanic region near mumbai may have killed the dinosaurs. The gas made from eruption is then inhaled by the dinosaurs to eventually kill them. The fumes were too strong and with the chemicals, that are strong too. For the dinosaurs that were gonna give birth. Then that will lead to less population.

17. Video

18. Bibliography Youtube www.lifestudiesonline.com Kid rex

19. End of Presentation
Thank you for watching our presentation and I hope you enjoyed it! Any questions? If you don't understand anything feel free to ask.