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The Size of Megalodons
How large was the megalodon that your tooth came from?
Jayson KowinskyHow large did megalodon get? Obviously, we know they had massive teeth, with the largest having over a 7" slant height. But what does this tell us about the size of the shark? Since we only have fossil teeth and vertebrae to look at, determining the shark's dimensions has been a problem for some time. The first attempt at a jaw reconstruction took place in the early 1900's by Bashford Dean from the American Museum of Natural History. The reconstructed jaw exceeded 10 feet. Based on this jaw reconstruction, it was believed megalodon could get over 100 feet in length. However, these reconstructions were based on unassociated sets of teeth, as no associated teeth had yet been found. Today, we know megalodon were much smaller than this. More recent research, based on associated partial dentitions, show that a megalodon with 5 - 6" teeth would have had jaws roughly around 6.5 feet wide and 8 feet high. One of these unassociated reconstructed dentitions can be seen online at the Calvert marine museum.
Now that we have a better idea of the size of a megalodon jaw, how big did megalodon actually get? In 1996 Gottfried, et al, published a paper that has a formula to calculate the megalodon length based on a megalodon second upper anterior tooth (A II). The formula is as follows:
Length in meters = [(.96 x A II slant height in cm) - .22]
From this formula, if you have an anterior tooth, you can determine the size of your shark. If you do not have an A II, you will have to "guestimate" the size of the A II based on the tooth position you have (not very scientific). Now, for you lazy people who know your tooth size in inches, and do not want to convert, I made a quick chart to find the size of the megalodon based on the AII tooth size in metric and english. The chart is as follows:
Chart showing A II tooth height and corresponding megalodon length
Some of the largest teeth found, 7+", would have come from a shark nearly 60 feet in length! This is pretty impressive. Remember that a modern Great White can reach a maximum length of around 22 feet. Therefore, a large megalodon would have been almost three times the size of the largest Great White! This is even larger than the largest fish today, the docile Whale Sharks, which can obtain lengths of up to 46 feet.
Most megalodon teeth that wash up on the beaches at the Calvert Cliffs are between 1.5 to 4 inches, which means the megalodon were around 12 to 30 feet in length. This indicates mainly juvenile megs were present (probably due to the shallow conditions of the Calvert Sea). However, larger megalodon were occasionally present. For instance, the largest tooth I have (a C. subauriculatus) is just over 5", and therefore came from a shark over 40 feet in length.
