Spinosaurus News ~

[DrZapxX]

Let's give you the benefit of the doubt here, then. Assuming Spinosaurus DID have a pneumatic neck, we need to take into account that it would have been denser than solely the pneumaticity suggests, as Molina-Pérez & Larramendi point out. As I have linked for the Google Books, they estimate the density of dinosaurs with far more air sacs than Spinosaurus would have had to have already had a density of 0.95, and that crocodilians (the relatively best model for non-maniraptorans, especially spinosaurids) have a density of 1.05 given their lack of airsacs, not simply 1 as one might expect, falling close to the disparity of what the theropod densities are when taking into account and not taking into account tissue density. And SpinoInWonderland's older Spinosaurus supports this well; with a density of 0.9 in the head and neck (as Scott Hartman used without taking into account the denser tissue) and crocodilian-like density in the rest of the animal, the density is overall 1.035. Not to mention, even extant birds (which are the theropods best known by far for being pneumatic) lose their pneumaticity and air sacs when they become semiaquatic. As Wedel et al. 2003 and Schorger et al. 1947 have noted, a very well known diving bird (the loon) has no postcranial pneumaticity at all, just to throw an example out there. And that makes sense, considering being as highly pneumatic is a very large hinder to a diving lifestyle as Spinosaurus is thought to have had. Therefore, based on absolutely EVERYTHING I outlined above, I find a density of at least 1 if not a bit more to be the most realistic by far. And where does Ibrahim (2020) suggest pneumaticity? I am not aware of this.

Benefit of the doubt? It's pretty clear spinosaurus had a pneumatic cervical vertebra, and deep gaps at the back, from FSAC-KK-7280 and FSAC-KK-18122,theres direct evidence supporting it for it for crying out loud, how can spinosaurus have a SG of 1.0 if it had some sort of air spaces? 1000kg/m3 is based on no airspaces? Crocodllians/other specific theropods aren't good for example for spinosaurids because they simply have no air sacs at all, anything with air spaces the density is deceased of 1000kgm/m3, tissues vary in density too.

Now with SpinoInWonderlands spinosaurus density, which is greatly overexaggerated (this is before Ibrahim et al 2020 incase you forget, MSMN V4047's mass is ten tonnes, imagine with the corrections how heavy it would be!) I got a density of 1 and not 0.9.

Going by 1 litre = 1kg for FSAC KK11888

4443.13 litres = 4443.13 kg

Volume in m3 (1 litre = 0.001 cubic metre (1000) 4.44313 cubic metres)

Thats a speciffic gravity of 1.0 not 0.9? what are you talking about 0.9? Where are you getting that from?


Density = mass/volume

4443.13/4.44313 = 1000 kgm3

Thats a speciffic gravity of 1.0 not 0.9? what are you talking about 0.9?

I'm not sure where you got Hartman's density, and date of publication is essential too.

Speaking of sauropods, I checked Henderson 2003 and it doesn't mention anything on the state of lungs when being calculated specific gravity if anything according to a blogpost, by open of the authors of the paper... Mathew Wedel, https://svpow.com/2009/03/16/brachiosaur...ncomplete/ states he calculated the density of Diplodocus too high he left out air spaces that were too difficult to calculate volume, the volume occupied by the lungs and air sacs, should have been doubled, so if what Larramendi is saying is true, this would compensate however I not fully read Wedel 2005 to double check.

It should be taken into account that Henderson 2003 doesn't mention diplodocus anywhere, and calculates volume of 4 different sauropods which I've mentioned, even Larramendi guesstimates density around 0.9, not really support by no backing up for his claims either.

That is not true, many semi aquatic birds still have hollow bones, terns, gannets, and pelicans, also are divers and have hollow bones, also little grebe a diving bird in the exact reference you gave about loons have a density of 0.86 despite having solid bones (but they do have air sacs), also it has been proved by Henderson et al 2018 that Spinosaurus was unsinkable, being to little dense to dive into water, also before you argue that it would roll, Ibrahim et al 2020 has addressed that argument, the tail fluke would decrease the potential ability to roll and stable the animal during locomotion.
Also air sacs are an evolutionary advantage for regulatory and biomechanical needs for which a large spinosaurus would benefit.



They don't suggest pneumaticity but they consider it an option for  FSAC KK11888's density and mass

''What SpinoInWonderland simply did was superimpose the rostrum (which is 98.8 cm long according to the Theropod Database), onto an image of a complete but privately owned Spinosaurus skull, and then given the rostrum length of 98.8 cm, the whole skull ended up at 1.86 meters. Is that really so hard to understand?

Finally, just because he isn't a palaeontologist doesn't mean he can't do good work. As far as I can see he did the best he could due to the fact he used 100% conspecific material.''


See this is where I'm starting to get the impression you are cherrypicking, why make it overcomplicated than it should be, just simply apply isometry, a 32% of a 112cm FSAC-KK 11888's skull to get MSMN v4047's skull length of 150metres which is bang on what Therrien and Henderson got, as well as Ibrahim and colleagues.These are multiple experts saying the same thing in multiple papers and not a single image from not even an qualified expert,

just like what you said about trusting Ibrahim supposed opinions over evidence, you are changing it by then contradicting Ibrahim himself on another point.

No the thing is you are not supporting any of your claims with reliable evidence, don't forget palaeontology is a science, you've barely supported your claims with any scientific literature (studies, especially done by the peer review process) all you've done is mainly took SpinoInWonderlands blogs and opnions as well as poor sources like images for example for gospel you can't just link someone whos not a palaeontologist, you can get references from him who have been done by qualified experts in their fields but that's mainly it you have to have a origin of your references.



''Your argument of using a different taxon goes completely down the drain considering that SpinoInWonderland used nothing except Spinosaurus skull material to get 1.86 meters. That's it.

Also, using a different taxon does not necessarily make for an overestimate. Mind explaining just how and why theropod1's reconstruction for example may be overestimated? It uses different taxa but to his knowledge it still holds.''

So did Ibrahim and Therrien, The morphology of skulls on spinosaurid is drastic, theres too much variation upon spinosaurids, especially posteriorly to get an accurate size, isometrically smaller relatives of a given genus to obtain body length is unreliable because those smaller theropods do not have proportional skull to body length sizes infact scaling actual spinosaurus material ,FSAC KK11888,should be the most reasonable and gives 150cm.

''I'll ask this again. Can you explain how an equation based primarily on short tailed tyrannosaurids with no Spinosaurus material in its base sample size is superior to using actual Spinosaurus material? With the latter, that is how lengths of 16-17 meters or so are obtained.

Also, Henderson (2018) states 16 meters as you can see here.''



I just did at the bottom, I don't know where you got the idea that Therrien et al 2007 specifies in short tailed tyrannosaurids? Really tyrannosaurids? there's only two that was in the paper at all.How do you know that even either with certainty?


The digital model itself was 15.5 (based on Ibrahim et al 2014) metres which was rounded to 16


''What does that have to do with this?''

That skeletal diagram was to show why Mickeys short tailed argument is invalid, simply because they have similar tail lengths are similar size, don't forget unusual theropod body plans like ornithomimosaurs and oviraptosaurs were discredited 


''Now sure, it has a higher density. But still very likely not high enough.

Also, would you mind explaining just why the corrected version is so wrong considering I have put absolutely everything I could about it in line with current Spinosaurus knowledge and that is what led to such a high mass? Not to mention it matches the new model of the neotype at the same length almost perfectly, I see that as more confirmation that my corrections were on point.''


Based on what, even if what your saying is true, 918 kg/m3 is higher than the minimum you said is for spinosaurus which according to you is 0.9, also the limbs of Hendersons spinosaurus was 1.05 SG

I checked page 7, barely anything could be taken with consideration barely any sources at all. Reply