What did the megalodon, this sea monster that dominated the oceans 2.5 million years ago, look like?
The subject divides the scientific community.
This species is mainly known for its teeth, which are found in many deposits around the world.
Immense teeth, which often exceed the size of a human hand, and which are enough to make you shudder when you imagine the face of their owner.
The megalodon is therefore often described as a super predator capable of roaming all the seas on the planet and being able to measure up to 20 meters long, but also quite stocky, like the white shark.
However, the animal could have presented a much more slender silhouette, and this calls into question certain assumptions about its behavior...
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New work, published in the journal
Palaeontologia Electronica
, presents a slightly different megalodon profile.
“
This study was prompted by an article published in
the journal
Science Advances
in 2022
,” explains Romain Vullo, paleontologist at the University of Rennes-1.
He is signing this new study with 25 other shark experts from 29 academic institutions around the world, including the United Kingdom, Austria, Italy, Japan, Mexico, Brazil, France and Australia, as well as the United States.
“
In 2022, the authors presented the megalodon as a sort of super white shark, particularly based on the analysis of the teeth.
From then on, they drew several conclusions about his behavior.
We show here that the fossil data we have contradicts this idea.
»
A hundred vertebrae
Although numerous teeth have been identified in the scientific literature, there are, however, very few fossils of the skeleton of this giant fish.
However, there are around a hundred vertebrae preserved at the Royal Belgian Institute of Natural Sciences, in Brussels, having belonged to the same individual and discovered in the 19th century in Belgium.
It was described in 1996.
“
Based on the diameter of the vertebrae of this specimen and in comparison with the white shark, the estimated length is 9.2 meters.
However, when we add up all of these vertebrae, we see that the size of the specimen was at least 11.1
m
, explains Romain Vullo.
This size is a minimum, because there is nothing to indicate that vertebrae are not missing.
This demonstrates that the white shark is not a good model for attempting to reconstruct the length and shape of the megalodon body.
»
The megalodon must therefore have been proportionally less stocky than the white shark.
The consequences of this new estimate of the size of the megalodon go beyond just the silhouette of the animal.
Because
“
from the moment its morphology differs, all the elements that brought it closer to the white shark in its behavior fall away,”
judges Romain Vullo.
From the shape of the body, the authors of the article published in
Science Advances
explained that the megalodon was a transoceanic apex predator, that is, it was capable of traveling great distances, like of the white shark.
All this, by domino effect, is therefore denied.
»
The authors suggest in particular that it would not have needed to hunt very often, thanks to a very long digestive tract;
its morphology could also have made it a relatively weak swimmer, much less than the current white shark.
Also read: What if the megalodon still existed?
Less good hunter than the shark?
The megalodon therefore remains a mystery.
A terror which, with the
Tyrannosaurus rex
, is perhaps one of the largest carnivores to have ever populated our planet, as the size of its teeth suggests.
It was in the 17th century that we first became aware that giant sharks once populated the oceans, thanks to the comparison of what we thought were dragon teeth with shark teeth.
Since then, discoveries have multiplied and with them more or less fanciful theories on the possible survival of the predator.
Fictions like the comic book
Carthago
or the film
In Troubled Waters
thus maintain the myth of specimens of megalodons still living in remote areas of the oceans.
But according to work published in May in the journal
Nature Communications
,
its disappearance was caused by a cooling of the oceans at the end of the Pliocene (2.6 million years ago) which would have brought in the whales, on which it fed , to migrate towards the Arctic zone, where the waters had become richer in food.
Thermally limited, the megalodon was probably not able to follow them and found itself in competition with large, more general predators, such as the white shark.