Spinosaurus News ~

[DrZapxX]

It turns out that Ibrahim et al 2014 overexaggerated on FSAC KK 1188 Spinosaurus's length, the 11 metres was a roundup of 10.37m (however this could been a revised length from Ibrahim et al 2020 but since it overexaggerated 14 to ''over 15 meres'' I am sceptical) which + 32% equals = 13.688 metres

''Nowhere did I say that those were not assigned to Spinosaurus. What I said was that the assignment is not 100% certain.''

Your kind of having doubt of it, we have no other option but to say they are Spinosaurus, I don't know how FSAC KK 18118 isn't spinosaurus when it's clearly been assigned to spinosaurus but sure.

''Not necessarily, I have shown how it's possible for that not to be the case. And tissues do vary in density, but because muscle and blood (1.06 kg/l) as well as bone (2+ kg/l) and probably many more are denser than water, that would mean that a density of 1 or more is still possible even when there are airsacs. I don't know how many times I explained this already.''

Idk where you shown that, blood and bone is a trait to many animals and they still have a total density around 1000km/3 including pneumatic birds.

''I did specify that, maybe you just didn't read my post close enough. But give it a try yourself; the total volume of the head and neck is 1073.69 litres, while the rest of the animal is 9595.86 litres. If you multiply the head and neck by 0.9, and the rest by 1.05, I am not aware of any way to get an overall density of 0.9.''

No, you really didn't, you just said SpinoInWonderlands image supports you with a density of 1+ despite a 0.9 neck, which the actual image does not have 900km/3 density in the head and neck also the thing is about that, that because the litres = kg and then volume is kg/1000 the density will always be a 1000, any total litres of volume will always have a 1000kg/m3 density



''I'm not Hartman but he could have got them from Bates et al. 2009 (come to think of it, his densities are probably a bit conservative based on the work of both Bates and Larramendi).
''

Bit of an assumption to be honest.You just assumed this.



''
I'm a little bit lost on this. In my last post to you, the response paragraph that simultaneously dealt with Hartman's densities and what kind of density Aerosteon was likely to have had did not reference SpinoInWonderland's work.''

Oh, you was only responding to the last sentence of the quote, I don't know why you quoted the density calculation on SpinoInWonderlands image on imgur, but ok.

''Sereno was not looking for a density for Aerosteon. Molina-Pérez and Larramendi were, however, and on every theropod in their book a graphic double integration was used with the 0.95 density. And I therefore will need evidence that a megaraptoran tyrannosauroid that's so pneumatic it was named for the air in its bones is going to have a higher density than an aquatic spinosaurid megalosauroid which could plausibly have been denser than 1 based on modern relatives. ''

I am not saying Aerosteon was more pneumatic than Spinosaurus, I am going to assume they assumed a 0.95 density because it would have been higher than the 0.9 density of
more pneumatic sauropods?

''This abstract from Wedel's paper suggests otherwise; it seems as though dead and inflated birds were used as reference.
''

I've checked the abstract, (this wasn't in the PDF I read) I also read the introduction too, where does it say this? Can you quote?

https://arxiv.org/ftp/arxiv/papers/1302/1302.3267.pdf

'Also, the things Wedel did not take into account were that the density of normal, relaxed sauropods is much higher as well as tissues being denser than water to begin with. Furthermore, Larramendi has outlined how the air spaces were overestimated in the original density of 0.8, and not even birds are that pneumatic when relaxed. Not to be blunt but you haven't been refuting Larramendi's proposition at all; you're just ragging about old stuff that his density estimation took into account.
One last thing. I've spoken with Wedel in SVPOW's comments, and he thinks 0.9 is viable these days. So in conclusion, for Spinosaurus to have been significantly less dense than sauropods really does not seem viable from known data.''

You see Larramendi is being contradicted by the words of Welder himself who said he underestimated Diplodocus's air spaces, birds can have much lower densities than that some as low as 0.6, you see if we take Larramendi's supposed increase to 0.9, by changing the sauropods to a relaxed position, changing the soft tissue densities, and air space proportion this would have a 100kg/m3 increase, which is surprising has not a lot of effect, even when Welder missed out air spaces this would had to be <0.9 anyway, so if anyone Larramendi is overestimating specific gravity.
Welder's comment also states 0.85 is just as reasonable too.

''Are they really? They appear to spend more time in and around water and less time in the air going by what I could find.
And nowhere did I say they couldn't fly, I said they did not seem to fly as much and were solid boned with a high density due to that.''


I would say so according to Padilla 2015...

''Grebes are small- to medium-sized, heavy-bodied birds with long necks and feet set far back on the body. They have an almost exclusive aquatic lifestyle and are limited in mobility when on land.''

''I'll go over Henderson further down, but I don't see why a discrepancy of more than 32% is dubious or incorrect. With the newest model and with the skulls restored using the same criteria, I am not able to replicate a mere 32%.
Also, they simply restored the skeleton and got 11 meters or so. That's all that was done.
''
Because Ibhraim et al 2014 states this? If anything it should be less, since they overexaggerated alot of the values in the first place and Therrien et al 2007 agrees it's consistent with that 32% increase

They didn't really back it up with any evidence, they just said 11 metres that's it, btw this would still give a 8700kg value at 14.5 metres.

''Exactly how it sounds, facts that are correct. Which can be just as viable non-peer-reviewed as they are peer-reviewed as long as they are correct.
(An example of this would be saying that Spinosaurus was a reptile. That's just as correct coming from a non peer-reviewed source as it is from a peer reviewed one because it is factually correct that dinosaurs are reptiles and therefore peer review does not matter in that case).''

Ok then, I'll rephrase, how do you know its factually correct? The thing is it's more than that, your not even referencing genuine Palaeontologists, just one guy, the difference this, there is many peer reviewed literature supporting that from other a century?


''Why don't you actually take some time to point out why you think my images are wrong instead of constantly just ragging about no peer review as you are doing now? I don't need peer reviewed material for the above reasons, but what you need to do is actually point out why you think it is wrong.''
Why don't you show actual sources backing the ''factually correct'' ideas up at least, and then I would give it more attention?


''And I am here to defend my viewpoints.''
I wasn't attacking yours in the first place?

''I don't see what is so false about this. With both skulls restored using the same criteria, I just could not replicate a 32 percent size difference, and I don't know what Ibrahim did to get 32%. Simple as that.''


They isometrically scaled both fsac kk 1188's premaxillae to msnmn v4047's premaxillae and got a percentage increase.


''That does not matter. What matters is how factually correct it is, and like I said before you don't seem to have any refutations save for the fallacy of no peer reviewing.''
Yes it does, you can't show 20 sources that are not scientifically reliable, and I did though.

''Those can be used interchangeably when referring to things like dinosaur skeletals.''
You don't know for certain, we are taking this for literal, head =/= skull, Ibrahim et al 2014 specifically states skull, Ibrahim et al 2020 states head,.

''Everything had been explained in those posts. Including what changes had been made to the model, why those changes were made, and how they were made. I really do not see how that is no sources at all and just poor resolution images.''
Because all of it was just coming from you? You aren't a source, you need to have sources backing your claims, its really that simple.Everything you linked were images.

'That doesn't change the fact that the results from Therrien and Henderson (2007) end up too short compared to what 100% Spinosaurus material would yield, because for a given mass Tyrannosaurus is shorter than Spinosaurus. And that was my point, that that formula overestimates the weight but seems to underestimate the length.''

I would say it was only off by less than a metre

Fsac kk 11888's supposed length 10.37 metres
Apply a 112cm skull gives 1.03161 * 10^(0.85673*Log(Skull Length)+0.93482) = 9.7836 metres this is off by half a metre (a 5.99% difference) and Paul's Tyrannosaurus has a longer tail proportionally than Ibrahim's 2020 spinosaurus restoration.

''I'm failing to see how being simplistic makes it wrong. The reason it was so simple is that all that needed to be done was superimpose the rostrum on a complete and undistorted Spinosaurus skull. That's it.
And I find his skull reconstruction the most probable (but nowhere near gospel contrary to what you may think) given that it uses only Spinosaurus material. Just like I said before.''

Because why wouldn't Palaeontologists have done something so basic and simple in the first place, also I did the exact same thing and got less than 150cm, based on Ibrahim's 2020 skeletal.


''Then please explain exactly what makes my non peer-reviewed arguments factually incorrect.''
I have already.


''Mind explaining how? It's simply what I find most probable, I think you know as well as I do that I am taking nothing for gospel here.''

You take his findings and evidence for your own, it's self explanatory nearly 90% of the time you reference him.

''Nothing wrong with referencing him as much as I do, he is a good source so far as I can see.''

Really? I can reference other members of the Paleo community then? Who I agree with.Anyone can reference any enthusiast .


''That sounds like they are talking about the Ibrahim et al. 2014 model rather than the model that was used in the study. And given that nothing else was rounded off in the data table, I find it most likely that the 16 meter estimation refers to a non rounded measurement of the study's own model.''

''The length of the model was also based on the new restoration of Spinosaurus by Ibrahim et al. (2014).'' It was based on Ibrahim et al 2014.


''Now DrZap, I say this with all due respect, but I think it's time that you and I drop the debate with one another. We've had this debate multiple times already, it's been going on for quite a while, and we have been beating around the bush a lot. I also don't know if I'll change your viewpoints regardless of whether more people believe you or me.
Anyone else who would like to know more can feel free to ask me about anything, but I'd like to respectfully drop the debate with DrZap specifically for the reasons above.''

Fair enough I guess. I should have saw it before then I wouldn't have wrote all of this. Reply