Tyrannosaurus rex vs. Giganotosaurus carolinii

[kekistani]

Jan 23, 2020 2:10:38 GMT 5 jdangerousdinosaur said:

Do we really need any more of your size comparisons at this point though ? This whole site is full of them. Many of them with questionable accuracy and that has been brought to your attention plenty of times now. You can cherry pick the specimens all you want to and you can use older estimates all you want to but it does not change what everyone else seems to know and mostly accept apart from you.

Right now with the most current and most reliable data Tyrannosaurus is the overall largest theropod currently known. This has been said to you what seems to be over 150 times. I have told you countless times others have told you on here others have told you this on other forums and the whole theropoda discord server a whole community that is very strict when it comes to accuracy has told this time and time and time again. You just do not want to accept this. You are letting your emotions and your bias get in the way of raw data and when it comes to these kinds of discussions that is just not the best way to go about this.

(comparison created by Maxilla Diagrams from Franoys)


You have been told i dont know how many times that Frans work is the best stuff that we have right now by many people who know far better than you do. You say Frans work is to conservitive but im sure if he had Carnosaurs such as Giganotosaurus and Mapusaurus out massing Tyrannosaurus you would be completely fine with his work. I have told you all of this before and yes at this point you are quite clearly just being ignorant. This is the biggest issue people have with you and why you have been banned from the Theropoda discord and then the GDI server.
You keep bringing up averages all the time yet it has been pointed out to you so many times that with the little fossil evidence that we have there is no reliable averages for either of these animals. You want to convince others that Giganotosaurus is larger than Tyrannosaurus on average yet we have no way of knowing this and there is nothing concrete suggesting it right now. There is nothing wrong at all with comparing either Sue or Scotty with the Giganotosaurus holotype. Scotty is a well preserved specimen and is pretty much at the same level of completness to the Giga holotype while Sue is the best preserved Tyrannosaurus specimen. You just do not like them being compared to the Giganotosaurus holotype because they are larger than it is its just that simple. Scott Hartman compared Sue to the holotype no problem thats because there is no problem with it. Its a perfectly fair comparison to make and he has no bias for or against any animal invloved and if he does well he does not let it get in the way of his work. You realy should try doing that sometime.

Yes it feels pointless at the point saying this for the 100th time but sadly more and more people are visiting this site to learn about these animals and to get the best and most accurate infomation.

I don't think people come to this site to get accurate info, just to see better AVA's than Carnivora.
I cant stop them coming here but i can atleast pick apart your often biased views and thankfully its not just me anymore doing it. Its very possible in the future our views on this will change. We will follow what the data shows us thats just science. But right now Tyrannosaurus is the overal largest theropod going from sheer mass.

Well said

[dinosauria101]

Woah there, woah there.

If you don't like my size comps, no need to go all out like that. I believe Tyrannosaurus and Giganotosaurus to be pretty similar in size and either could be larger depending on how things like density are used. The other carnosaurs could possibly be larger or smaller depending on how they are restored, and I am aware there are no averages in fossil animals, we can just discuss which specimens would beat which specimens.
If we're going to go down this rabbit hole, I'm out. Franoys' work is good, but it's not the only possible interpretation nor is it set in stone.

And by the logic you're using, there's also nothing wrong with comparing either Giganotosaurus to a specimen like USNM 6183. Again, we can compare various specimens to see which ones beat which ones.

[dinosauria101]

How about we try and turn the discussion away from petty arguing now, and debate which specimens would beat which specimens?

In regards to the Giganotosaurus holotype, I think it would easily win to some of the smaller Tyrannosaurus specimens like Bucky, B-rex, and USNM 6183, and would either lose to Sue or Scotty or it would be around 50/50, depending on density.
I would favor the holotype over some similarly sized specimens slightly, such as MOR 555 (6.1 tonnes IIRC), AMNH 5027 (6-7 tonnes depending on density), Stan (6.5 tonnes?), and the holotype of Rex (6.2-7 tonnes), due to larger/longer jaws, larger forearms, and larger gape.

[spartan]

What advantage would a higher density even provide?

[dinosauria101]

Alright, so here's a post from theropod that explains Tyrannosaurus pneumaticity very well. From here

The density?
Volumetric estimates have suggested higher densities for Carnosaurs than for Tyrannosaurus (Bates et al. 2009a, b, Hutchinson et al. 2011).

And the pneumaticity in T. rex is extreme:

www.paleoglot.org/files/Janensch%2047a.pdf

Similarly, the development of the pleurocoels in Tyrannosaurus (Osborn 1917) is extreme. They occur in the cervical vertebrae, in at least the majority of the dorsal vertebrae and even in the first two sacral vertebrae.

The precaudal vertebral column was heavily pneumatized, with pneumatopores penetrating the centra and neural arches of all presacral vertebrae, the cervical ribs, and the anteriormost four sacral centra

He also gives what is probably the reason for the differences between specimens in Hutchinson et al.:

Postcranial pneumatopore asymmetry and intraspecific variation are to be expected (Britt, 1993), and specific pneumatopore patterns on FMNH PR2081 differ somewhat from other T. rex specimens.

The femur in Sue was also described as hollow, and the anterior caudals also bear pneumatic foramina.

As opposed to this, basal tetanurans have pneumatic cervicals and anterior dorsals, and perhaps dorsal ribs and posterior dorsals in some species (Holtz et al. 2004).
At least some megaraptorans developed a greater degree of pneumatisation (Aerosteon). Mapusaurus has a pneumatopore on the first sacral, but no further than that (Coria & Currie 2006), indicating the abdominal airsacks were way less extensive.

With all this, I think we can rely on the figures from Bates et al. and Hutchinson et al. (2009, 2009, 2011) for approximation.

Another way would be to use segment masses as a demonstration:
Hartman assumed the torso and neck (including the tigh) to have a specific gravity of 0.9. By comparison, the density of the thorax and tigh in Allosaurus sp. (Bates et al. 2009) was merely 0.778 with an abdominal airsack included. It seems like the 0.9kg/l put what is definitely over 60% of its mass at more than 15% too dense (T. rex was more pneumatic and the volumetric guess is conservative), so that could easily lower its overall mass by about 10% or more.
We could take this further if we had the precise volume measurements for the respective segments of course, which, sadly, we lack to date, but this makes a net density of ~0.8kg/l seem fairly plausible.

By any reasoning on the issue the new estimate certainly revises Hartman's earlier 6.4t figure for Sue, and I appreciate the clarity in this regard (also having an estimate actually based on a high-quality model closely approximating the in-vivo proportions instead of a compromise-mount or a useless regression equation).
I cannot say I'm very surprised by the result considering they were at the same density–the ratio ends up remarkably like what I had previously predicted from the lateral area measurements.

Then of course sample size still comes into this. Comparing MUCPv-95 to Sue (as Hartman already stated a comparison of specimens, not species) to compare the taxa's respective sizes is biased, just like comparing MUCPv-ch1 to Bob or Bucky-the former cannot realistically be expected to be as large an individual, the latter not as small an individual.
Bob, scaling down from Hartman's unaltered figure for sue, would be ~4.5t, and with an adjusted density as above, only ~4t.
This specimen is much smaller than the smallest Giganotosaurus (only 57-66% the size), while the largest Giganotosaurus even when disregarding the density is almost the same weight (98%), and perhaps even heavier than the largest T. rex–so by conclusion, Giganotosaurus’ size range is higher.

I wouldn't be totally sure of the thoracic width either but that's not my main point, we can be quite sure Tyrannosaurus has a comparatively broad torso. Even tough the Giganotosaurus seems excessively slender, even more so than a conservative model for Allosaurus sp. (and that altough it should be wider at least in the pictures since it had more spine curvature), the unknowns are pretty big.

References:
Bates, Karl T.; Falkingham, Peter L.; Breithaupt, Brent H.; Hodgetts, David; Sellers, William I.; Manning, Philip L.:How Big Was ‘Big Al’? Quantifying the effect of soft tissue and osteological unknowns on mass predictions for Allosaurus (Dinosauria: Theropoda). Palaeontologia Electronica, Vol. 12 (2009); 2; pp. 1-33
Bates, Karl T.; Falkingham, Peter L.: Estimating maximum bite performance in Tyrannosaurus rex using multi-body dynamics. Biology Letters, Vol. 8 (2012); 4; pp. 660-664
Brochu, Christopher A.: Osteology of Tyrannosaurus rex: Insights from a Nearly Complete Skeleton and High-Resolution Computed Tomographic Analysis of the Skull. Memoir (Society of Vertebrate Paleontology), Vol. 7 (2003); pp. 1-138
Coria, Rodolpho A.; Calvo, Jorge O.: New Specimen of Giganotosaurus carolinii (Coria & Salgado, 1995), supports it as the largest Theropod ever found. Gaia, Vol. 15 (1998); pp. 117-122
Coria, Rodolpho A.; Currie, Philip J.: A new carcharodontosaurid (Dinosauria, Theropoda) from the Upper Cretaceous of Argentina. Geodiversitas, Vol. 28 (2006); 1; pp. 71-118
Holtz, Thomas R.; Molnar, Ralph E.; Currie, Philip J.: Basal Tetanurae. In: Weishampel, David; Dodson, Peter; Osmólska, Halszka: The Dinosauria. Berkeley (2004); pp. 71-110
Hutchinson, John R.; Bates, Karl T.; Molnar, Julia; Allen, Vivian; Makovicky, Peter J.: A Computational Analysis of Limb and Body Dimensions in Tyrannosaurus rex with Implications for Locomotion, Ontogeny, and Growth. Vol. 6 (2011); 10; pp. 1-20

With this taken into consideration, I think it's reasonable to conclude that Sue and Scotty were very similar in weight to MUCPv-Ch1, and the latter outweighed many Tyrannosaurus specimens quite a bit. Going by this, it's also highly likely that Tyrannotitan, Mapusaurus, and Carcharodontosaurus could seize the top spot as well; they could very well be >7.3 tonnes.

[spartan]

That doesn't answer my question, though.

[dinosauria101]

I wasn't replying to it.

I've chosen not to respond to a whole bunch of the above posts should all hell break loose again.

[Ceratodromeus]

"all hell breaking loose"

...

What? Just because you don't like what is being said doesn't mean "all hell is breaking loose."

[dinosauria101]

I meant long, heated, unnecessary quibbling when I said all hell breaking loose

[Ceratodromeus]

...yeah thats what im referring to. It's a debate forum. If you don't like it you shouldn't have even made a comment.

[dinosauria101]

Yes, this is a debate forum. However, a few things.
-That comment was not meant to directly address the posts above
-The last little bit seems to be veering off a bit from the main topic, so that's the issue. Unnecessary heated quibbling.

[Ceratodromeus]

I really think you argue to argue at this point. That is, until you have to try and divert and fallaciously dig your way out of the hole you dig for yourself. Case and point, when you fallaciously claimed my post had "personal jabs" at you when it really was critical of your argument structure. You did the same thing there as you have here, and that's the only reason its being brought up.

"i wont be replying because insert contrived reason here".


Just drop it, you continue to do yourself zero favors here.

[dinosauria101]

I don't even know what the post I am not replying to says. Literally, I was ignoring it.

[Ceratodromeus]

I would suspect that isn't for a solid argumentative reason either.

[dinosauria101]

It was, as I said earlier, to keep things from flaring up.