The most powerful and fearsome predatory reptile of all time

[Grey]

Benson regarding giants pliosaurs :

I've not seen any pliosaur teeth with crowns that size (400 mm) of any age. 
However, sometimes people report tooth length including the root. This 
can more than double the 'tooth length' compared to the actual crown 
height. The largest material in the Oxford CLay comes from 
Liopleurodon, which was actually quite small compared to Pliosaurus or 
Kronosaurus.

In the UK/Europe, the largest teeth are from Kimmeridge Clay-aged 
strata, and belong to Pliosaurus. We covered its size maximum well in 
our paper. The biggest pliosaurids are from the Cretaceous, and 
include the Harvard specimen of Kronosaurus (from Queensland), which 
is pushing on a 13 metre body length. Bones/teeth from this individual 
are quite a bit larger than most other specimens I've seen. Because 
the near-complete skeleton is known, it provides good evidence of the 
largest size attained by pliosaurids - at least those known in the 
fossil record so far.

Could there be 20 metre long pliosaurids. It's possible. However, I 
don't beleive that there is currently any evidence.


I don't know why Colin thought that Kronosaurus was much smaller than 
Pliosaurus. The individual bones of the MCZ Kronosaurus are all larger 
than any Pliosaurus material I've seen (and there's a lot out there). 
The centra and skull are especially large, whereas the limbs are 
approximately the same size. The brainase, which is quite nicely seen 
in ventral view in the mount, is truely immense. People are often 
dissmissive of the MCZ specimen, calling it "Plasterosaurus" for
example. However, Romer & Lewis provided measurements of some of the 
individual vertebrae, and also explained how their length measurement 
for the postcrania derived from articulated lengths in the field 
jackets. So I think it is harder to question than is often said. 
Kronosaurus boyacensis is an articulated skeleton from Columbia that 
has a length, lacking the tail, of 9.5 metres. I don't know for sure 
how long the tail should be, but if it was 3 metres then it would
approach ROmer & Lewis estimate for thei MCZ Kronosaurus specimen.

You can see the bite marks on the kevani skull in our figures and 
they're not exceptionally huge. I don't know much about the Aramberri 
specimen bite marks. I'd like to see pictures/descriptions of the
evidence. Do you have a scan of the relevant pages? It is possible for 
bites to cause bone infections that turn into abcesses and remove a 
larger amoung of bone than the size of the tooth, so I am reluctant to 
use that as evidence of body size.

One of the funny things about even the largest Late Jurassic 
pliosaurids is that they lack signs of osteological maturity such as 
unfused neurocentral sutures. It's possible that none of the current 
material is not fully grown. However, it is also possible that these 
taxa never closed their sutures for some reason. There is a lot of 
material out there and I'd be surprised if we hadn't found the largest 
ones yet.

Of course, it would be nice to find strong evidence of super-giant 
pliosaurs. But I don't think there is any so far.

I should add to my last email:
I think Romer & Lewis did overestimate the skulll length for the MCZ 
Kronosaurus by about 1 metre. This is the part of the skeleton they 
had least complete. This reduced their length estimate to about 12 
metres. It is explained in the Pliosaurus kevani paper.

[Grey]

Strange that nobody reported that article by Forrest :

plesiosaur.com/plesiosaurs/weymouthscience.php


"The FEA analysis showed also that the bite of P.kevani was enormously powerful. It estimates biting force towards the back of the jaw of around 40 tons. It was almost certainly greater than this: a recently published paper comparing computer models of bite forces with measured forces in lizards showed that the methodology used underestimates the force by 20%. In addition, the analysis was not carried out on the more recent reconstructions of the skull which increase the depth at the back and therefore increase the power of the bite by increasing the size of the muscles. Taking this into account, it can be reasonably argued that a force of over 50 tons is realistic. To put this into perspective, the ‘jaws of life’ – the device used by emergency services to cut to roofs off cars in a couple of minutes – exert a force of 50 to 150 tons depending on the model."

That's a monstrous bite force figure.

That's strange that this not correspond to the results from Foffa published few months later. This is ten times stronger than Foffa's results.
I asked him, he ignores how Forrest got these results and found them way too excessive.

I cant join Forrest yet, asking him about the reported 400 mm teeth and now this bite force estimate by FEA different than Foffa's figures.

[Infinity Blade]

This bite force thing sounds interesting. I'm going to enjoy the discussion on it.

[coherentsheaf]

Thank you Grey for the Benson mail. A few remarks: Whle MCZ1285 s certainly very large I believe the Romer and Lewis estimate to be overinflated based on the number of restored vertebrae as discussed in McHenry. Its average vertebrae size also suggests it to be smaller than the Monster from Aramberri and depending on accuracy the Cumnor monster was as large or larger as well, though Benson raised doubts on the restored length of this specimen. Regarding K. boyacensis: Afak the preserved part s just in excess of 7m making an estimate of 12m total implausible.

[coherentsheaf]

Nov 27, 2014 10:09:50 GMT 5 Grey said:

Strange that nobody reported that article by Forrest :

plesiosaur.com/plesiosaurs/weymouthscience.php


"The FEA analysis showed also that the bite of P.kevani was enormously powerful. It estimates biting force towards the back of the jaw of around 40 tons. It was almost certainly greater than this: a recently published paper comparing computer models of bite forces with measured forces in lizards showed that the methodology used underestimates the force by 20%. In addition, the analysis was not carried out on the more recent reconstructions of the skull which increase the depth at the back and therefore increase the power of the bite by increasing the size of the muscles. Taking this into account, it can be reasonably argued that a force of over 50 tons is realistic. To put this into perspective, the ‘jaws of life’ – the device used by emergency services to cut to roofs off cars in a couple of minutes – exert a force of 50 to 150 tons depending on the model."

That's a monstrous bite force figure.

That's strange that this not correspond to the results from Foffa published few months later. This is ten times stronger than Foffa's results.
I asked him, he ignores how Forrest got these results and found them way too excessive.

I cant join Forrest yet, asking him about the reported 400 mm teeth and now this bite force estimate by FEA different than Foffa's figures.

Gven the overall size of the skull, 40 tonnes seem implausibly high.

[theropod]

That sounds fairly ridiculous actually. Rather looks like a unit conversion error.

[creature386]

I hope the original number was 40,000 lbs…

[theropod]

Maybe rather 40 000N but mistakenly believed to be kilos? In that case it would be compatible with estimates given by Foffa et al. 2014.

[Godzillasaurus]

So how large has this pliosaur been estimated at? An unusually-large specimen would make this 40-50 ton figure more credible, even though it still does seem to exceed the likely limits hugely. Then again, we are also discussing the fulcrum of the jaws, where the bite would be at its ultimate strongest, so there is also that.

And also something to consider is that, unless it is going to be hunting small and shallow-bodied creatures (such as sea turtles), this bite force would represent something that cannot be used in predation simply due to the angles of the jaw when it is agape.

[theropod]

Nope, we are not discussing the fulcrum of the jaws. Obviously an animal cannot bite there, the posteriormost point it can bite with is the last tooth position, and that’s also what posterior bite force numbers refer to.

The specimen in question is Pliosaurus kevani. I’ve already made a thread posting its official description paper, several others in this thread have referred to it, and so has the article in question.

[creature386]

Nov 27, 2014 22:19:38 GMT 5 theropod said:

Maybe rather 40 000N but mistakenly believed to be kilos? In that case it would be compatible with estimates given by Foffa et al. 2014.

That's of course also possible. But to be honest, I don't see why it is so hard to write kN instead of conversing.

P.S. I sometimes make that conversion error, albeit rarely.

[theropod]

Nov 28, 2014 19:49:32 GMT 5 creature386 said:

Nov 27, 2014 22:19:38 GMT 5 theropod said:

Maybe rather 40 000N but mistakenly believed to be kilos? In that case it would be compatible with estimates given by Foffa et al. 2014.

That's of course also possible. But to be honest, I don't see why it is so hard to write kN instead of conversing.

Me neither, but I also don't get why he would claim P. kevani to have a 40-50 ton bite force when the only published figure is smaller by a factor of ten (albeit plausibly itself underestimated, just nowhere near that much).

[0ldgrizz]

The pliosaurs were bigger, but I believe that a big mosasaur, like Bruce who measured roughly 43 feet long, might could out-maneuver the bulkier pliosaur.

[creature386]

Deciding the most powerful predator is not only about who would kill the other in a face to face fight.

[0ldgrizz]

OH, ok, my mistake, sorry. Then, in sheer power, it might be more of a contest between the biggest species of pliosaur and Megalodon. I don't know enough to even make a guess. Both awesome to say the least.