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by Kayla Walker
Physical Geology
Spring 2008


Lord of the sea


Lurking in the cold depths of our modern ocean lives a creature that for many years has inspired fear and awe in the hearts of man. A massive predator, perfectly designed, rules the oceans unchallenged. It has survived for years unchanged within the fossil timeline. At a record 23 feet long and eight feet wide, the white shark is the largest predatory fish in the sea. It is often the first image that enters our minds at the very mention of the word shark. It hunts full grown Elephant seals, is capable of great burst of speed, and lives in every ocean on our planet. But as terrifyingly awesome as this large predator is, it is a mere spec in the sea compared to the super predator that ruled our ancient seas.

Photo: Great white shark and diver

Carcharodon Megalodon literally meaning “Giant Tooth” or “Rough Tooth” is just that. It is a massive super shark found by the Swiss- Born American zoologist Louis Agassiz in 1843. We know this species only by its fossil teeth and a few precious vertebrae that it has left behind. These fossils have been found all over the world indicating that this super predator ruled its ocean environment without equal. The fossil teeth of this animal can reach an impressive 7 inches across, roughly the size of a human hand. Compared to the teeth of a white shark that, at most reach only 3 inches across.                                

Due to the size of the teeth and the growth rings of the vertebrae, scientists first suggest that this creature was over 100 feet in length with a jaw that was 10 feet across. Later observations however proved that the initial estimates were off considerably. The earlier scientists were working with little evidence and believed that current White sharks reached a length of 35-40 feet, so it was sensible to make the first Megalodon three times as big. The current estimations are still incredible. Megalodon had a jaw more than 6 feet wide, a body that was 40 – 60 feet in total length and weighed in at an awe-inspiring 77 tons. This makes it the largest predator ever to grace our planet. Much larger than even the most infamous of the dinosaurs, the Tyrannosaurs Rex. Weighing in at only 7 tons and 40 feet in length, Megalodon would have had no problem slicing through this, once thought, ultimate predator.                    

However, Megalodon and T-Rex would have never had the chance to prove the above theory. Fortunately for T-Rex, the rise of Megalodon was after the fall of the dinosaurs. T-Rex ruled the land during the Cretaceous period around 65 million years ago. Megalodon began to rule the seas during the Miocene and Pleistocene period only 20 million years ago, making it a fairly young fossil development, geologically. It is currently argued as to when exactly Megalodon ceased its reign of the ocean. The most accepted theory is that it died out over 1.3 million years ago due to the cooling of the oceans and the migration of its main food source, whales. Some state that it became extinct as recent as 11,000 years ago. However, nothing dies harder than a big fish story.  Still others argue that Megalodon is alive and well today. These crytpozoologists believe that since humans have only explored less than 5% of our oceans Megalodon could be thriving down in the deepest and darkest trenches of the ocean, feeding off the rising populations of whales. Megalodon sightings are reported every year, yet most are just cases of mistaken. No hard evidence has as of yet, been presented that Megalodon is still haunting our oceans, but nothing will deter these die hard believers.
(We’re gonna need a bigger boat!) JAWS 1975

Megalodon is also debated in the area of classification. Many scientists believe that the modern great white is the closest living relative, if not direct descendant of Megalodon. However others believe that the White shark came about the same time as Megalodon did geologically. They believe that both species are from the family Isuradiae, the family of the modern Mako shark. It is theorized that the White shark stuck to the colder deeper waters and fed on early seals, while Megalodon stayed near shore in the warmer waters preying upon whales. This theory runs into problems because many believe that Megalodon was warm blooded and that its immense girth forced into deep water, not inshore estuaries. The entire basis of these arguments is placed on nothing more than the space between the serrations of the teeth which vary considerably from tooth to tooth. As sharks bodies are made of almost entirely cartilage it is near impossible for an entire shark body to be preserved.  Thus all science has to argue over are the hard parts, teeth. Based on these two theories Megalodon was either a warm blooded predator that stalked whales and other mammals, or it was a cold blooded predator that terrorized large schools of fish. Until more evidence for the classification of Megalodon arises, most scientists hold fast to the theory that Megalodon was the great grandfather of the modern White shark.

            By studying the feeding habits of white sharks today science can get a glimpse of how these massive predators satisfied what must have been an enormous appetite. In the same way that full grown White sharks chow down on the energy rich blubber of seals, Megalodon is thought to have dined on blubbery whales. Several fossil whale bones have been found with nicks and grooves that closely resemble the bite mark of a Megalodon shark. It is thought that this animal had the same hunting technique as the White shark, just on a grand scale.  It is theorized that it would stalk a pod of whales from below watching their prey silhouetted against the surface of the water.  With a great burst of speed it would attack from behind and below, biting of the tail and immobilizing the whale. It would then circle back and finish its prey, making light work on the carcass with its powerful jaws.

            This awesome predator still today inspires us with fear and amazement. Just to see one tooth and imagine what the rest of the animal must have looked like can give you the chills. It is no wonder that Megalodon jaws are popular attraction at zoos, aquariums and museums. It is also no surprise why some hope and believe that it is still around today. To physically see such a perfectly designed predator of such a grand scale would be the ultimate adrenaline rush. Mankind is and has always been obsessed with the sea and the mysterious it holds. Countless books movies and pictures are created every year continuing to deeper mans fascination with the ocean and the creatures that call it home. Megalodon was the ultimate predator and must have been the true lord of the sea.



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