Sarcosuchus imperator vs Carcharodontosaurus saharicus

[theropod]

But the
increased depth in spinosaurus' rostrum is rather an adaptation more-so
for increased vertical resistance in gripping, as it hunted very large
fish but yet did not kill with similar force-related tactics as
sarcosuchus. Such exceptionally deep rostra are not necessarily factors
that indicate crushing (even though tyrannosaurids possess relatively
deep rostra, the depth present is nowhere near as specialized as that of
carcharodontosaurus. But does that mean that carcharodontosaurus had a
more robust rostrum?

That depends on the COMBINATION of vertical and lateral resistance.

Spinosaurus' increased depth rather indicates that vertical stress would
not be a problem in gripping, because it did not bite so forcefully
unlike sarcosuchus.

What? How is that related?

Take deinosuchus and carcharodontosaurus for example, one had a much
deeper snout while the other possessed a far more robust rostrum that
was better designed for gripping resistance and crushing.

As you may have seen by now, DeinosuchusÂ’ snout is in a different league of robusticity compared to Sarcosuchus. ItÂ’s built like an Alligator, Sarcosuchus like a Mecistops.

It is really the same thing with sacosuchus and spinosaurus; one is far
better adapted for crushing while the other was generally more gracile
in build and was rather reinforced vertically.

Again, you seem to be assuming some congruence where there is none. Firstly, SpinosaurusÂ’ rostrum being deeper does not have anything to do with it being supposedly more gracile. And secondly, thatÂ’s because it isnÂ’t.

Both animals were well adapted for gripping, so there are not many variables in that regard.

Carcharodontosaurus, as you pronouced for several times in the (wrong) assumption this necessarily suggested it had a gracile snout, is certainly not well-adapted for gripping, unless you consider a scimitar a suitable hook for a crane or a knife a suitable ice axe.

The depth in spinosaurus' rostrum is again an indication for increased
resistance in that direction; specifically attributed to it specializing
in tackling large fish. The teeth of spinosaurus were well adapted for
gripping most of all, so the killing style specifically revolving around
such quick and precise puncturing still remains hypothetical. But
interestingly, the increased depth does seen to correlate perfectly with
its tooth morphology in that the increased vertical resistance
parallels with the ability of its conical teeth to pierce deeply more-so
than in sarcosuchus and similar animals. But again, this is more likely
attributed to spinosaurus being well adapted for gripping large fish
most of all as opposed to killing.

As a sole adaption for gripping, a greater depth makes no sense. As a sole adaption for gripping, longer, more pointed teeth donÂ’t either. That deep puncturing played an important role is beyond doubt. And that it MUST have killed its prey somehow is too.

Spinosaurus' rostrum was not exceptionally
deeper in relation to wider, this was only slightly the case. It was
not specialized to have been used in one certain direction to kill prey;
it was well adapted for gripping.

And? Any point in repeating what I wrote?

I thought that torsional resistance and gripping resistance were synonymous; they were not.

Of course gripping a large animal requires great torsional resistance. But that gripping automatically means great torsional resistance is another matter entirely. Spinosaurus did not have to and far all we know did not bite and hold onto large, struggling animals that it would have to control with its jaws. It had to snatch, impale and pull out fish, or dispatch mid-sized dinosaurs. Neither requires immense torsional resistance.

The point is quite simply that the morphology present in spinosaurus
does not imply that it was weak one bit and instead is an implication of
a big chunk of its diet revolving around the gripping of impressively
large fish. Naturally, increased resistance both laterally and
vertically (multidirectional. This is rather not found in the other two
genera) is a necessity with a killing style revolving around gripping
and would be more-so present in spinosaurus than in allosaurus or
carcharodontosaurus, as the former animal was well adapted for gripping.
So what if carcharodontosaurus and allosaurus had a wider rostrum
relative to length; they were still very poorly adapted for the same
kind of gripping of large and powerful animals as found in spinosaurus;
they were only adapted for killing quickly and vertically. Their snouts
would not necessarily break in the event of gripping, but they were
still simply poorly-adapted for such forceful handling of large prey and
skull damage overall is a far greater possibility due to the lack of
such gripping morphology but rather the opposite (far deeper rostrum
that was much less heavily-constructed and was only well adapted for
vertical resistance as opposed to multidirectional. As well, teeth that
are also only adapted for working vertically and in pulling motions;
they were not conical and designed for piercing deeply). The greater
width of allosaur snouts are not necessarily exceptional or for a
specific purpose, and predation/killing instead relies more on their
impressive rostral depth and serrated teeth to cause tissue damage
and/or intense blood loss:

Ok, that was probably the longest and most confusing sentence I ever read.

You are implying a number of problematic things; firstly "carnosaur rostra were not specialized for gripping, thus they had lower lateral resistance".
---ThatÂ’s not relevant in this form, the animals they attacked were vastly different in size, shape and power.
Carnosaur rostra may be more fenestrate, but they are considerably wider. This will probably make them resist bending in all dimensions better.
You simply donÂ’t quantify all those assertions and just go on taking them as facts.

Secondly, "that would mean they are not more robust".
----Again, carnosaur rostra very likely transmitted and resisted much greater forces, and we know with a fair amount of certainty they were extremely strong. That alone makes them highly robust, even though it applies to the vertical plane only. Lateral strenght has never been properly analysed or compared for these two. Thus, donÂ’t speculate, but take what we have. Two species, one decidedly longi- and gracilirostrine, although perhaps less pneumatic, another very deep, comparatively broad, built to excert large forces. You can go on comparing their skulls and will see the difference.

Just that an animal had gripping teeth does not automatically mean it had particularly robust jaws. Just that an animal had slicing teeth does not mean tis jaws werenÂ’t robust.

There is no reason to believe that carcharodontosaurus was even in
possession of a more robust rostrum, and even if it was, the stresses
found in predation would be much smaller.

Firstly; no probably not.
Secondly; how is this relevant?

 There is also no reason to believe that the stress found in gripping
large animals would be much less intense in the realm of skull damage
for allosaurus than spinosaurus just because it had a proportionally
wider snout; the much more voluminous but yet far less
heavily-constructed structure of allosaur rostra would make such lateral
pressures far more damaging not in the realm of the entire structure
breaking but rather the sheer force being exerted causing different
kinds of damage such as intense fracturing (this is not limited to
completely going through the entire structure). Spinosaurus was far less
vulnerable in this regard, as its snout was fundamentally more robust
and was designed to grip large animals with a reduced risk of any sort
of injury first and foremost; allosaurus was poorly adapted in this
regard, and its snout would be particularly vulnerable due to its
lessened ability to withstand lateral stress without fracturing. Width
doesn't mean everything, but rather an animal's adaptations to do so in
which case spinosaurus has the clear advantage in gripping.

Please quantify "far more heavily constructed".

Please elaborate. How do you see a crocodile snatching fish from above, like a heron, or a Spinosaurus? SarcosuchusÂ’ snout is extremely shallow, which is perfect for quickly whipping through water in a lateral swing of the skull. ThatÂ’s the way crocodilians catch fish.

And what use does such a generalized shape
have in the first place, especially when the teeth in that region do
not indicate similar functions as those of spinosaurus

It is not a "generalized shape", it is a shape specialized for enlarging the naris. ThatÂ’s its purpose. Its dentition is similar to that of a 1t Crocodylus porosus, certainly not built to handle particularly large forces for an animal of such size.

But what we instead see in sarcosuchus is
rather increased resistance, high aptitude for crushing, and greater
macrophage ability in the premaxilla by comparison to the posterior
regions of the snout. What other leverage do you guys have to prove that
it was a weak structure besides the sinuses?

Funny, because LEVERAGE was what I was gonna say, and what I did already explain in the paragraph you responded to.

Which is a highly logical configuration of material; anteriormost part
being the weakest, because thatÂ’s also where the bite and postcranial
forces are lowest, due to simpley leverage.

Even if its premaxilla was built to be so strong, which is wasnÂ’t for all we know, why have a super-strong premaxilla on a considerably weaker maxilla, when the largest forces could be excerted at the maxilla, and the forces excerted with or on the premaxilla would inevitably be transmitted on it too?

Sarcosuchus did not have a weak maxilla...
And even if you guys claim that it was because of its similarities to
mecistops, I'll have you know that mecistops does not have a
particularly weak maxilla either.

Well, surely SarcosuchusÂ’ premaxilla is not as strong as that of a Saltwater crocodile of similar skull or body size. therwise it would probably be at least remotely close to being as wide and deep.

[Godzillasaurus]

As you may have seen by now, DeinosuchusÂ’ snout is in a different league of robusticity compared to Sarcosuchus. ItÂ’s built like an Alligator, Sarcosuchus like a Mecistops.

I realize that; the point being that having larger dimensions do not necessarily indicate a more robust rostrum. So carcharodontosaurus' rostrum was far deeper than deinosuchus, but it should be a no-brainer as to which animal is in possession of a more robust rostrum.

Again, you seem to be assuming some congruence where there is none. Firstly, SpinosaurusÂ’ rostrum being deeper does not have anything to do with it being supposedly more gracile. And secondly, thatÂ’s because it isnÂ’t.

How come whenever I make decent analogies, people always refute them as begin ridiculous? Having a deeper rostrum does not imply having a more robust rostrum! This only seems to be the case when the compared animals have similar rostral widths, builds, and specializations, such as tomistoma and spinosaurus for example. One is wider at the base but for the most part is generally quite narrow while the other animal is in possession of a comparably narrower snout at the base but is characterized by greater depth which seems to compensate for the animal's high aptitude for its teeth to pierce deeply and for increased dorsal resistance in more large-scale piscivory. The increased depth rather seems to be for increased resistance in that direction for tackling such large fish without breaking. The considerable depth present in spinosaurus' rostrum was not an adaptation for killing.

As a sole adaption for gripping, a greater depth makes no sense. As a sole adaption for gripping, longer, more pointed teeth donÂ’t either. That deep puncturing played an important role is beyond doubt. And that it MUST have killed its prey somehow is too.

That is not what I was talking about. I have explained this before, the depth present in spinosaurus' rostrum does not necessarily imply a high aptitude for killing. What it is instead is an adaptation for considerable vertical resistance in gripping the large fish that made up the majority of its diet and to simply accommodate for the morphology of its teeth (to pierce deeply within the hide of a very large and powerful animal) without the structure being damaged (this is not necessarily evident of being well designed for killing). Sure, the dentition of spinosaurus was very well designed for piercing deeply first and foremost, but their morphology suggests that they would have punctured into the hides of large fish and were able to maintain a very stable grip without breaking (the same thing goes for its snout) over creating fatal puncture wounds necessarily. Just as the impressive depth found in allosaur rostra implies high aptitude for killing through forceful downward motions, the considerable depth present in spinosaurus' rostrum seems to rather indicate simply higher resistance vertically to prevent breaking in hunting.

They sure could have been used for killing (and were more-than-capable), but in that case an even deeper rostrum would likely have been evolved if they were designed for that specific purpose. Spinosaurus' rostrum was adapted to withstand balanced multidirectional stress: decent lateral and vertical stress alike as a feature for reducing any sort of injury in gripping. If it was well adapted for killing, we would most likely not see decent resistance and strength in both directions but rather far more emphasis on depth if anything.

Of course gripping a large animal requires great torsional resistance. But that gripping automatically means great torsional resistance is another matter entirely. Spinosaurus did not have to and far all we know did not bite and hold onto large, struggling animals that it would have to control with its jaws. It had to snatch, impale and pull out fish, or dispatch mid-sized dinosaurs. Neither requires immense torsional resistance.

And that is what spinosaurus was adapted to do... Gripping large and very powerful fish... There is no reason to believe that spinosaurus' snout was incapable of withstanding the pressures found in such specialized predation. This seems to be evident in its: generally heavily-constructed snout (particularly compact and dense. It did not possess exceptional dimensions, but this seems to be an implication for increased gripping resistance), balanced dimensions (not specialized in depth or width but rather is more balanced for reasonable strength in both directions), and strong and conical dentition best designed for piercing and gripping. The characteristics that indicate strong gripping resistance outweigh those that imply killing aptitude.

Such impressive density found in spinosaurus' rostrum is clearly an adaptation for resistance purposes. Conical teeth, especially those found in animals with slender snouts, are best designed for piercing and gripping, that is the basic point here. Could they have been used for killing via well-placed and quick impaling? Yes, but that is not what they or its snout as a whole was evolved to do best.

---ThatÂ’s not relevant in this form, the animals they attacked were vastly different in size, shape and power.
Carnosaur rostra may be more fenestrate, but they are considerably wider. This will probably make them resist bending in all dimensions better.

Not necessarily. The exceptional depth that is present in carcharodontosaurus' rostrum was clearly a morphological feature suggesting killing. It was very lightly-built but yet was very deep and was studded with knife-like teeth that worked best with pulling and causing ripping damage/blood loss. IT DID NOT NEED TO HAVE IMPRESSIVE LATERAL RESISTANCE IN ITS SNOUT; I can't stress that enough. The ability for it to effectively transmit and resist vertical stress is attributed to its downward and pulling killing characteristics.

We do not see these features in spinosaurus. And what we see instead is conical teeth (they can be used for killing, but that function is entirely hypothetical for now), a much denser and more heavily-built rostrum, decent multidirectional strength, and a slender shape by comparison (for reducing drag in water; this does not make it a weak structure as I have stressed enough lately).

Also, the ability for spinosaurus to have the capacity to grip large fish is attributed to its high resistance and ability to avoid injury (this ability in spinosaurus is heavily underrated just because "itt hadd a thinn snowt!". Its snout was designed to grip large animals effectively without breaking (despite having a slender snout, it was very strong as I have said several times already), so risk of injury is not as imminent as you make it out to be (and it certainly is not evident). Allosaur rostra do not necessarily have to break entirely, but the more lightly-constructed design of them would make stress fracturing far greater of a possibility than what we see in spinosaurus (simply put, the more light build of its snout would be disadvantageous, regardless of width). So what if it was wider, spinosaurus' rostrum was designed to GRIP LARGE AND POWERFUL ANIMALS without breaking or fracturing while carcharodontosaurus' rostrum was not and would be far more vulnerable in this regard.

Secondly, "that would mean they are not more robust".
----Again, carnosaur rostra very likely transmitted and resisted much greater forces, and we know with a fair amount of certainty they were extremely strong. That alone makes them highly robust, even though it applies to the vertical plane only. Lateral strenght has never been properly analysed or compared for these two. Thus, donÂ’t speculate, but take what we have. Two species, one decidedly longi- and gracilirostrine, although perhaps less pneumatic, another very deep, comparatively broad, built to excert large forces. You can go on comparing their skulls and will see the difference.

The width in carcharodontosaurus' rostrum was not designed for force delivery or resistance; it was literally just there (probably to accommodate for its very deep profile if anything) and serving no specific predatory function. The far more impressive density and build of spinosaurus' rostrum in addition with reasonable dimensions does not indicate that it was very weak but rather the opposite; it was indicative of high resistance in gripping and allowed the creature's snout to effectively do so when capturing decently-sized fish without breaking.

Simply put, allosaur rostra were only necessarily very special in regards to their ability to efficiently both exert and resist vertical forces. Spinosaurus' snout was structured more robustly and was not very special in either direction but instead possessed enough strength in its jaws to withstand the pressures found in gripping. And yes, far more-so in spinosaurus than in carcharodontosaurus.

It is not a "generalized shape", it is a shape specialized for enlarging the naris. ThatÂ’s its purpose. Its dentition is similar to that of a 1t Crocodylus porosus, certainly not built to handle particularly large forces for an animal of such size.

And so this makes it adapted for piscivory how? And even if the morphological features present in this region did not indicate any sort of resistance or strength in opportunist feeding, the posterior portions of its snout was not necessarily weakly-build anyway. Using mecistops as an analogy for sarcosuchus and using that to "prove" that it was in possession of a weak rostrum is like claiming that the Sun is the biggest star in the universe because it was the biggest from your point of view (it was nowhere close to this and was instead actually only moderately-sized in terms of stars); mecistops was not really a weak animal either and nor is tomistoma. Both species are by scientific definition generalist crocodilians that had no problems taking down large animals (false gharials have been known to kill macaques and deer before).

For an animal that is characterized by a much more robust premaxilla (by comparison to both tomistoma and mecistops) that was clearly not designed for such specialized piscivory but instead the direct opposite to be more weakly-built in terms of rostral morphology is ludicrous. I have explained to you why such a large hole is not restricted to sarcosuchus and is even found in genera like deinosuchus even; it did not necessarily merit a weak structure.

Even if its premaxilla was built to be so strong, which is wasnÂ’t for all we know, why have a super-strong premaxilla on a considerably weaker maxilla, when the largest forces could be excerted at the maxilla, and the forces excerted with or on the premaxilla would inevitably be transmitted on it too?

THAT I cannot answer. The premaxilla seems to be the most optimal region of its rostrum to be used in macrophagy based on what morphological evidence we have; that is all I know.

The spinosaurus specimens MNSN and MNHN are particularly robust (posterior to the premaxillae of course), so you can use those for reference. 

[thesporerex]

I favour Carcharodontosaurus, I will post why later because right now I don't have the time

[Godzillasaurus]

What are your reasons?

[creature386]

He said he will post them later.

[Deleted]

And he never did.

[creature386]

lol, who would've thought that someone would point that out four years later?

[Deleted]

I actually spoke to Thesporerex today on external websites and he told me he will "post it later."

[dinosauria101]

Dinosaur on land, crocodile in water