The world’s oceans cover over 70% of the earth’s surface. Unfortunately, climate change is meaning this surface area is increasing to the detriment of life on land. While humans are fascinated by what occurs under the sea, according to the U.S. National Ocean Service, more than 80% of the world’s oceans are unmapped, unobserved and unexplored[1]. With such mystery lying underneath the surface, there are many unanswered questions. While many know the megalodon to date back to prehistoric times, so little is known about the specifics of this creature. This had led some to ask is the megalodon still alive?
AnimalWised answers this question by looking into what might have caused the extinction of the earth’s biggest sharks. We also look at the characteristics of the megalodon, characteristics which seem mythic despite their scientific basis.
The megalodon shark belongs to the order of Lamniformes, this includes the best known shark species, including the great white shark. Within this order the megalodon falls into the Otodontidae family, which today is believed to be completely extinct.
How did the megalodon look?
Megalodon teeth have a series of pores along the surface of their roots. This is where the teeth connected with the circulatory system to supply nutrients to the continuously developing teeth. This indicates that the nutritional system of the animal was very complex. A shark which replaced their teeth which such high frequency would have high nutritional needs.
From this, it has been intuited that the megalodon was large and aggressive, it fed on large prey and it had a high metabolic rate. Current models made from comparisons with the great white shark indicate the megalodon was very fast, likely able to swim at a rate of 34 mph (55 km/h). This is faster than great white sharks which have been clocked at speeds up to 21 mph (35km/h).
When did the Megalodon live?
Otodus megalodon first emerged 25 million years ago and is believed to have become extinct 2 million years ago. Quick maths shows that they likely existed for a period of 20 million years. This period began in the Miocene period and ended in the Pliocene, specifically in the Cenozoic era.
Contrary to what many believe, the megalodon was not contemporaneous to dinosaurs. They arose long after their extinction, which is dated to 60 million years ago.
How much did a megalodon weigh?
Today, it is considered that the average length of the Megalodon was between 15 and 18 meters and that its approximate weight was 50 tons. As points of comparison, keep in mind that current white sharks measure around 4 to 6 meters, whale sharks 12.5 meters and the blue whale 25 meters.
When did the megalodon become extinct?
While there have been come cases of people who claim to have seen the megalodon in the current age, and others who speculate about its existence in the depths of the oceans, the scientific consensus is that the megalodon is indeed extinct.
The bigger question being explored by scientists is why the megalodon became extinct. The most recent study which has tackled this query has resulted in the most definitive answer of when the megalodon becoming extinct was 3.6 million years ago, during the Pliocene period[3]. The reason they were able to reach this number and believe its accuracy is due to an extensive and comprehensive analysis of all current fossil records of the megalodon.
Why did the megalodon become extinct?
While the megalodon was the largest predator of its time, this did not mean it didn’t have significant competition. During the last 2 million or so years of its existence, the megalodon coexisted with great white sharks, tiger sharks and other shark rivals. While adult megalodons were significantly larger than great white sharks, their offspring were not.
The greater competition exerted on the megalodon was not believed to simply be due to size. More important, seemingly, was their organization. During this time, killer whales were evolving. They were intelligent and organized animals which worked in groups to catch schools of fish. Besides smaller fish, they could also hunt juvenile megalodons.
Other contemporaneous whales noted for their great feeding skills were humpback whales. Humpback whales fish in groups, diving under water and exhaling in a cloud of bubbles as they do so. The bubbles cause the fish to rise to the surface where the humpbacks can simply open their mouths and ingest entire schools of fish.
At the height of the megalodon’s era, there were many whales belonging to many species. Food was abundant and competition was easier. However, around 3-4 million years ago there were worldwide changes to the ocean’s currents, leading to a phenomenon known as upwelling. Upwelling brought nutrient-rich waters to the surface, allowing the entire food chain to eat there. Due to the increase in upwelling, the amount of food available decreased and competition increased. Since the diversity of whales decreased, survival for the megalodon was severely impacted.
The cooling of the atmosphere likely also damaged the megalodon. Glaciers emerged which lowered the sea level, increased salinity and lowered the temperature.
The same study which dated the extinction of the megalodon to 3.6 million years ago, also pointed the blamed for its demise on rival predators, specifically the great white shark. Other reports suggest it could have been other predators, such as the tiger shark which was the culprit. What this says to the scientific community at large is that, while we believe the megalodon is not still alive, knowing exactly why is not yet possible to assert. What is most likely is that the reason for the megalodon’s extinction is multifaceted.
