Reassessment of the possible size, form, weight, cruising speed, and growth parameters of Otodus megalodon

[Protopatch]

A recent interesting paper in open access establishes the largest possible (reasonable) length estimate at 24.3 meters (80 ft) with a total weight around 94t, based on an incomplete vertebral specimen of †Otodus megalodon from the Miocene of Belgium :
https://palaeo-electronica.org/content/2025/5450-biology-of-otodus-megalodon
The researchers have also determined that the body form of O. megalodon likely resembled more the modern lemon shark - which has a slenderer body - than the modern great white shark.

[Protopatch]

We can also find this latest reconstruction of O. megalodon by Julius Csotonyi :



"The newest interpretation of this giant Miocene predator depicts it as possessing a longer, lankier body than extant species of Lamnidae that are typically used as inspiration for reconstructions."

[andrewsaurus rex]

Interesting new look for Ear Tooth Big Tooth.   I wonder if the size will hold up...a Sperm whale sized shark.

[Protopatch]

Yeah, unless they one day find more complete remains, the debate about its hypothetical size, weight, shape etc is probably far from being closed.

[andrewsaurus rex]

i prefer the great white shark look myself...too bad the science no longer really backs it up.

Finding more complete remains is only a remote possibility, sadly.  So the speculation about Megalodon will continue for a long time, most probably.

[stargatedalek]

I am extremely skeptical, something about this just feels like such wish-fulfillment. "It really was 80 feet long after all!" just feels like a conclusion so many people are already predisposed to want that I have trouble trusting it. It's like all those papers saying Spinosaurus "totally couldn't swim so it must have had long legs".

*edit* I've only read the first half of the paper but if I am correct... they're just using tooth scaling again but with a different reference this time? Like really? Shark teeth are highly variable in size relative to the rest of the animal and we have no good niche analogues to get any idea of the expected proportions of megalodons teeth. This really is wish fulfillment (in regards to length estimates [although some of the logic behind the new proportions is based on those new length estimates]).

I also find it suspicious that they just happened to end up with a new analogue for proportions that works better hydrodynamically if its 80 feet long that also becomes 80 feet long if they use it as a reference for the tooth scaling... I'm not saying the authors were (consciously) fraudulent by any means. But it reeks of them having approached this paper with a goal, perhaps even unconsciously, of proving it was 80 feet long.

[SBell]

It's too bad they don't have the one feature that apparently works universally for 'fish', the length between the eye and operculum AKA OrbitOpercularLength. It's how they shrunk the Dunk

[Protopatch]

I'm not saying the authors were (consciously) fraudulent by any means. But it reeks of them having approached this paper with a goal, perhaps even unconsciously, of proving it was 80 feet long.

True. I agree with you, but wouldn't it be the aim in fine of many paleontologists to push their papers in the direction they want (more or less unconsciously) ?

[dinofelid]

*edit* I've only read the first half of the paper but if I am correct... they're just using tooth scaling again but with a different reference this time? Like really? Shark teeth are highly variable in size relative to the rest of the animal and we have no good niche analogues to get any idea of the expected proportions of megalodons teeth. This really is wish fulfillment (in regards to length estimates [although some of the logic behind the new proportions is based on those new length estimates]).

It looks like their estimate is based on measurements of vertebrae rather than teeth, teeth only seem to come up when establishing that the vertebrae come from the same species as the teeth which are assigned to O. megalodon. The abstract says:

Here, we reassess some of its biological properties using a new approach, based on known vertebral specimens of O. megalodon and 165 species of extinct and extant neoselachian sharks across ten orders

And the "materials and methods" section says:

The key specimen for this study, an incomplete vertebral specimen of †Otodus megalodon from the Miocene of Belgium (IRSNB P 9893; previously referred to as "IRSNB 3121": Gottfried et al. 1996), consists of 141 associated, but disarticulated, centra up to 15.5 cm in diameter from one individual shark (Cooper et al., 2022). ... Both IRSNB P 9893 and the specimen from Denmark were not associated with any teeth, but they are assumed to have come from †O. megalodon based on 1) their exceptionally gigantic sizes; 2) the fact that teeth of †O. megalodon are known from Miocene deposits at each respective area; and 3) the fact that the vertebral morphology is consistent with that of the order Lamniformes which †O. megalodon belongs but differs from that of another large lamniform taxon, the basking shark Cetorhinus