If you have ever seen the movie Jaws before, the shark that was featured, actually lead to scientific papers, courtesy of the American researchers, that were able to detail information on transitional fossils connected to extant Great White sharks and Mako sharks.
The Great White Shark, also referred to as the Carcharodon carcharias, is thought to have descended from Carcharodon megalodon, more commonly referred to as the Megalodon shark, one of the largest fish that has been identified in the fossil record looking back 20 million years.
The Megalodon was identified as a result of fossil teeth that were first found in areas such as Australasia, the Americas, Asia proper, and in certain European settings where we shown to have been as long as 16 m, and despite its large size, was evenly proportioned. Today, however, scientists are becoming more uncertain about its relationship with the Megalodon and the great white shark that we have today.
Is There A Connection Between The Extinct Megalodon And Great White Sharks?
If you were to look at the official Order of sharks as they are known today, there is a bit of controversy regarding Lamniformes, specifically regarding cartilage that forms the skeleton of these fish. The problem originates from the fact that, in the fossil record, these skeletons are not preserved which is why so few fossils, other than their teeth, have been found by paleontologists to further the investigation.
There have been certain large jaws that have been discovered over time, some of which are in situ with jaws that have been found, with numerous teeth, in locations such as Peru where scientists have found very important indications that there is a direct connection with the modern day great white shark.
According to the fossil evidence that we have today, the ancient Megalodon was very similar in design to the great whites of our modern age, yet it may not have directly involved from the same lineage. Accordingly, Great White Sharks may actually come from a completely different ancestral line, specifically the nektonic Mako shark.
When looking at the remains of sharks with a Carcharodon genus, there does tend to be a phylogenetic relationship that can be identified, yet there are certain distinctions that are confusing. For example, when looking at the Megalodon again, they have discovered that Tiger sharks, tend to have more of a connection to great whites.
The Fossils Of Sharks And Their Teeth Similarities
Great White Sharks that have been studied today seem to be directly connected to the Megalodon. For example, when looking at serrations that have been categorized, located on the edge of the teeth, these are very similar when using a microscope that is able to carefully identify dentacles, which are simply serrations, which has helped in the identification process.
Since the Megalodon has been extinct for so long, all we have to go on are the serrations when comparing them to Great Whites, and professionals of noticed that the fossils are much larger by comparison.
In New Jersey, Prof. Dana Ehret, who is a research paper author, has suggested that the Megalodon is more connected to Carcharodon carcharias which is often thought to be related to Great Whites by paleontologists and those that studied the anatomy of sharks and Megalodon’s that can be found at certain institutions.
The basis of this information is the result of reconstruction projects where the extinct Megalodon is seen to be very similar to the Great White.
The Story Behind Serrated Teeth
Carcharodon megalodon and Carcharodon carcharias have very similar denticles or serrations which is how the sharks were able to cut through things so easily with their teeth, showing that there is a connection between the species. However, when looked at under a microscope, there are multiple differences that have been identified. Great Whites today tend to have serrations that are very course, whereas the Megalodon teeth were much finer in appearance.
Sharks teeth tend to have serrations, and this is true whether you are looking at a modern shark or one that is now extinct for which we have fossils. Indeed, there is a phylogenetic relationship, yet this tends to lead researchers toward the idea of convergent evolution playing a larger role in the identification process.
When considering convergent evolution theory, this refers to a couple different organisms that may not be very similar, but due to environmental pressures and outside circumstances, they soon find themselves closely related. An example of this can be found when you are looking at studies of bats, or birds, both of which have wings, but each one is extremely different; both bats and birds are not closely related at all.
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