The Megalodon shark is thought to be the largest ever species of shark to inhabit the seas. Yet, so little is known about how they lived, what they ate, and even what modern shark species they may be related to. Controversy still continues over whether they belong Carcharadon group of sharks and are related to the Great White or if they should be called Carcharocles megalodon and are not related to the White shark at all. The oldest remains of the shark currently known are about 18 million years old. It is believed to have become extinct in the Pleistocene era about 1.5 million years ago.
In its time the Megalodon was the largest predator in the sea and grew to around 60 feet in length. The biggest area of confusion is why the Megalodon supposedly went extinct. It was the apex predator and dominated the oceans for millions and millions of years, how does it just suddenly die out? Proponents for the extinction of the Megalodon propose that climate changes and a shortage of food may have been to blame. The waters around the time of the proposed extinction are the cooling down of the world's oceans. The Megalodon thrived in the warmer waters but may have had trouble adjusting to the cooler water and died out. However, if they are related to the Great White this theory doesn't really hold as the White shark seems to thrive in both warm and cool water, really only venturing to warmer waters to breed. It is also thought that a large number of the dolphins and whales of the time also went extinct around the same time, and would have created a shortage of the natural prey for Megalodon.
However, many believe that the Megalodon still lives in the oceans just out in the deep water where they are rarely, if ever, seen by humans. And there seems to be evidence to support this hypothesis. Sharks have always been and will continue to be a very hardy and adaptable species, who's to say the Megalodon didn't adapt as well? The cooling of the ocean was not a sudden thing. It was very gradual and took place over possibly millions of years, that is plenty of time for a species to adapt to the change. Other species thought to be extinct show up years later, much to the surprise of scientists. The Coelacanth was thought to go extinct 60 million years ago, until it was found in 1938. Now we know there is a still thriving population of these fish off the coast of Africa. The goblin shark and basking shark were also thought to be extinct at one time, until they also showed up unexpectedly. Who's to say that Megalodon isn't a similar case?
There have also been hundreds of reports by fisherman of seeing sharks that resemble Great Whites, but are upwards of 50 feet. That is over 20 feet longer than the largest White shark on record. While these reports are not substantiated the experienced fisherman making them see large sharks every day, and if they are surprised by the size of these sharks then we'd be foolish not to pay attention. Not to mention the thousands of longlines, fishing gear and nets that are lost to something very large that is unable to be contained every year. It is a known fact that less than 5% of the world's oceans have been explored and documented, new species are popping up every day. There is absolutely no reason a Megalodon shark couldn't remain undetected. They do have 95% of the oceans to roam and we would never know about it. Sperm Whales and Giant Squid are known to dive as deep as 12,000 feet for food. And if there is enough food for those giant creatures down there, there would be for Megalodon as well.
Finally, based on the average rate of deposit of mineral compounds on fossilized Megalodon teeth, the most current estimate is that some of the teeth are less than 11.000 years old. This is a far cry from the 1.6 million years that the Megalodon has been thought to be extinct. In geological terms 11,000 years is the equivalent of the Megladon being around last Wednesday. And if the Megalodon was still alive 11,000 years ago, there have been no dramatic or climate altering conditions that would have made that change. Just because we cannot unequivocally prove that Megalodon exists doesn't mean that it is extinct. There is no conclusive proof to say for certain that it isn't out there, still roaming the deepest parts of the ocean out of our reach.