The Megalodon shark is the biggest shark to ever live. Some remains of this shark have been found that are up to 18 million years old! The megalodon shark became extinct probably about 1.5 million years ago. It was the biggest predator of its time and the largest carnivorous fish ever known to have existed. This shark could grow more than 18 meters! (59ft) Just think of a fish the size of a six story building about to eat you! In medieval times large fossil teeth were often found in rocky formations and were thought to be petrified tongues of dragons and snakes. Fossils of this huge shark have been found nearly around the world. This shark was thought to have weighed 70 metric tons! The bite force of this shark is up to 40,131 pounds per square inch, which is 5 times greater than a T. rex. The extinction of this fish was likely caused by a shortage of food and the cooling of the earth’s oceans. (The last ice age) These sharks thrived in warm waters and had to have tons of food (literally) each day. When the ice age came the waters got colder, obviously, and when the waters got colder most whales went up to the polar region for food. Whales are a main food source for the Megalodon shark so they didn’t get enough food and the waters were too cold for them which lead to the extinction of the strongest predator that has ever been on earth.