Sunday, February 23, 2014

What Killed the Dinosaurs?

What Killed the Dinosaurs?

     Introduction

Dinosaurs lived during the Mesozoic era which began 245 million years ago. It lasted for about 180 million years. It was also known by the Age of the Reptiles. The era was divided by three eras. The Triassic, Jurassic, and the Cretaceous. The Triassic period was when all the continents on Earth were still connected. The super continent was called Pangaea. During the Triassic period(245 - 208 million years ago), Pangaea started breaking apart. Many reptiles, frogs, turtles, and crocodiles existed during it, but the dinosaurs didn't appear until the late Triassic. The first dinosaurs were lightly built, small dinosaurs. The first mammals formed during the Triassic period. The period ended with MASS EXTINCTION. During the extinction, wiped out entire order of plants and animals. But some still survived, which brings us to the Jurassic period. The Jurassic period started 208 million years ago and ended 146 million years ago. This was when the more larger dinosaurs started to form. This was period was known as the flourishing period of the dinosaurs. Birdlike dinosaurs first appeared during the Jurassic. But extinction also brought an end to the Jurassic, but it wasn't as large as the Triassic. At the end of the Jurassic, the Cretaceous period had began(146 to 65 million years ago). Pangaea had started breaking down into smaller pieces and had partially spread apart. Wide varieties of dinosaurs roamed and mammals had began to flourish. Birds had appeared and had spread all over the globe. But, again major extinction had struck the dinosaurs. The second largest extinction of all time brought an end to the age of the Reptiles, and the start of the age of the Mammals. But, extinction of the dinosaur species had brought an end to all three periods. But what had caused it? This question continues to rack the minds of all archaeologists around the globe.

   Archaeologists have many ideas of what had brought an end to the age of the dinosaurs. The most popular theory is the Asteroid theory. Many people think that a large asteroid had collided with Earth and a huge cloud of dust had blocked out the sun. Because many animals and plants need sunlight to survive, the change in climate had impacted the dinosaurs and had killed them.

  Another theory is Volcanic activity. Scientists believe that volcanoes had pumped so much ash into the air that it had blocked out the sun. Again, because of the sudden climate change, dinosaurs couldn't adapt fast enough and had become extinct.

  Some scientists believe that an small ice age had happened at the end of the Cretaceous. The sudden drop in temperature had negatively impacted the dinosaurs and had caused them extinction.

  My Opinion

Dinosaurs were abducted by aliens. Only reasonable explanation for the "extinction" of them. Aliens had taken them and possibly could have experimented on them. Fossils? While the aliens were taking the dinosaurs, the ones who either weren't taken, or "fought back" had been wiped out. This is my opinion.

Top 5 Dinosaur Extinction Theories

1. Asteroid Theory - Giant asteroid had collided with Earth and raised a cloud of dust and debris. The sun could not shine through so the dinosaurs and plants died.                                     

            

2. Volcanic Theory - Volcanoes puffed out so much smoke and ash, it blocked out the sun. The dinosaurs and plants did not have any sunlight so they died.

3. Ice Age Theory - A sudden ice age had killed the dinosaurs because of the sudden temperature type. 

 

4. Disease - A deadly disease had spread from dinosaur to dinosaur. When a dinosaur died, a scavenger had taken the disease by eating the meat of the dead dinosaur.

     

5.  Food Chain Imbalance - Herbivores ate plants and Carnivores ate meat. If the plants died out, the herbivores would die, and the carnivores would also die.

   

Top 5 Carnivores

1. Spinosaurus -

Spinosaurus was the biggest of all the carnivorous dinosaurs, larger than Tyrannosaurus and Giganotosaurus. It lived during the middle of the Cretaceous Period about 112 million to 97 million years ago, roaming the swamps of North Africa.

  

Giganotosaurus

2. Giganotosaurus was one of the largest meat-eating dinosaurs. It roamed the swamp lands of South America at the end of the Mesozoic Era, about 97 million years ago.

    

3. Tyrannosaurus Rex - 

Tyrannosaurus rex was a fierce carnivore. Scientists believe this powerful predator could eat up to 500 pounds (230 kilograms) of meat in one bite.

    


4. Carcharodontosaurus -

 Carcharodontosaurus was a carnivore, with enormous jaws and long, serrated teeth up to eight inches long.

      

5.  Carnotaurus -

Carnotaurus was a large predatory dinosaur that lived in South America during the Late Cretaceous Period. They had very small hands as well as horns above their eyes, and a short snout

 

Spinosaurus was the biggest of all the carnivorous dinosaurs, larger than Tyrannosaurus and Giganotosaurus. It lived during the middle of the Cretaceous Period about 112 million to 97 million years ago, roaming the swamps of North Africa.

  Conclusion 

There are many theories on how dinosaurs became extinct, many of them are actually true and are possible. I think that aliens abducted some and wiped out the rest. But of course, no one else seems to think that. Disease, Asteroid, Volcanoes, and Ice Age are the most common and popular explanations. Even though scientists aren't sure exactly what killed dinosaurs, they have many possible theories.


Challenge

What do you think caused dinosaur extinction? List your possible theories in the comments section.



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