Sharks have been swimming our oceans for nearly 450 million years giving them enough time to become one of the top marine predators we see today here in Gansbaai. The largest shark to have ever roamed our oceans was the Megalodon (Otodus megalodon). However, this enormous prehistoric shark, may have actually met its end due to a shark we see today – the great white shark.

Megalodon was the largest shark to ever swim in the ancient seas, reaching lengths of 15 – 18 metres. Fossil records suggest that megalodon sharks lived all over the world, in temperate, tropical and subtropical waters. Scientists have found fossils in both shallow coastal waters and deeper offshore waters. They believe that the habitat that megalodon sharks lived in depended on their age. Juvenile megalodons were spawned in shallow coastal waters hunting smaller marine mammals until they reached maturity. Once fully grown, they would head out to the open ocean to hunt larger prey like whales (sharksider).

The enormous prehistoric megalodon – © warpaint/Shutterstock

Common consensus is that a megalodon looked just like an enormous great white shark. However, this is not the case, as research suggests that megalodon sharks had a much broader dome shaped head, a shorter blunt snout and a flatter jaw than a great white shark. They also had extra-long pectoral fins similar to that of a blue shark, probably to support their ginormous size (sharksider & NHM)

According to an article written by Josh Davis for the Natural History Museum in order to eat prey as large as whales and fish, a megalodon had to be able to open its mouth wide. They estimated that its jaw would span a gigantic 2.7 by 3.4 metres wide! The megalodon’s enormous jaws were lined with 276 teeth and each tooth was between 15 and 18 centimetre (NHM). The Meg movie suggests that a megalodon’s jaws was strong enough to bite a whale in half, however, experts are very skeptical about this as they estimate a bite force of 24,000 to 40,000 pounds per square inch. This would only be enough to bite a small whale or dolphin in half if bitten at the right spot (Vulture).

A megalodon tooth next to one from a great white shark

A megalodon tooth next to a tooth of a great white shark – photo from nhm.ac.uk

According to research megalodon sharks reigned the oceans for roughly 13 million years. It was suggested that megalodon sharks became extinct around 2.6 million years ago. However, recent studies have challenged that date.

A new study by Robert Boessenecker, a paleontologist at the College of Charleston in South Carolina puts the extinction date approximately 1 million years earlier than previously thought. Boessenecker and his colleagues started searching for more evidence of megalodon sharks in California and then expanded their research to other regions. The samples in their compendium were from researchers, published literature and museum collections.

They combined their data with the previous 2014 study to create a mega – catalogue. The team reanalysed all of the data and found that the extinction of the megalodon must have happened 3.6 millions years ago – 1 million years earlier than previously thought.

Previous theories of why this giant apex predator became extinct included a supernova (explosion of a star) causing radiation poisoning in larger animals or a mass dying out of the megalodon sharks prey. However, this new date of extinction actually coincides with the rise of another ocean predator around the world– The Great White Shark, which made its global appearance 4 million years ago.

“We propose that this short overlap (3.6-4 million years ago) was sufficient time for great white sharks to spread worldwide and outcompete O. megalodon throughout its range, driving it to extinction-rather than radiation from outer space,” a quote from Boessenecker.

Even though great white sharks are much smaller than a megalodon shark, it is thought that great whites may have out-competed them for food. It is speculated that the larger numbers of great white sharks may have competed with juvenile megalodons for the same prey such as small whales which would have been scarce at the time. These stressors along with a changing climate was probably enough to wipe out the megalodon shark.

And yes… I know the blockbuster movie ‘The Meg’ got everyone’s imagination going, but these animals are extinct …. It is definitely safe to go back into the water.

Now the great white shark that was possibly responsible for the extinction of the largest marine predator also faces an extinction risk because of the world’s top predator – humans.

White Shark Projects believe that conversation education is vital for helping to save the endangered great white shark. We use our company as a platform to create awareness of how vulnerable these animals are and this issues they face. Educating clients, volunteers and using school outreach programmes to educate people on shark biology, conservation and how vital they are to our precious oceans.

Aiming to change people’s perceptions of these misunderstood beautiful animals.