Welcome Guest [Log In] [Register]
Welcome to Carnivora. We hope you enjoy your visit.


You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are some features you can't use. If you join our community, you'll be able to access member-only sections, and use many member-only features such as customizing your profile and voting in polls. Registration is simple, fast, and completely free.


Join our community!


If you're already a member please log in to your account to access all of our features:

Username:   Password:
Add Reply
Giganotosaurus carolinii v Tyrannosaurus rex
Topic Started: Jan 31 2012, 05:48 PM (110,345 Views)
Taipan
Member Avatar
Administrator

Giganotosaurus carolinii
Giganotosaurus ("giant southern lizard"), was a carcharodontosaurid dinosaur that lived 93 to 89 million years ago during the Turonian stage of the Late Cretaceous period. It is one of the longest known terrestrial carnivores, bigger than Tyrannosaurus, but in length and weight, smaller than Spinosaurus. Although longer than T. rex, G. carolinii was lighter and had a much smaller braincase that was the size and shape of a banana. A well-developed olfactory region means it probably had a good sense of smell. Titanosaur fossils have been recovered near the remains of Giganotosaurus, leading to speculation that these carnivores may have preyed on the giant herbivores. Fossils of related carcharodontosaurid fossils grouped closely together may indicate pack hunting, a behavior that could possibly extend to Giganotosaurus itself. he holotype specimen's (MUCPv-Ch1) skeleton was about 70% complete and included parts of the skull, a lower jaw, pelvis, hindlimbs and most of the backbone. The premaxillae, jugals, quadratojugals, the back of the lower jaws and the forelimbs are missing. Various estimates find that it measured somewhere between 12.2 and 13 m (40 and 43 ft) in length, and between 6.5 and 13.3 tons in weight. A second, more fragmentary, specimen (MUCPv-95) has also been identified, found in 1987 by Jorge Calvo. It is only known from the front part of the left dentary which is 8% larger than the equivalent bone from the holotype. This largest Giganotosaurus specimen is estimated to represent an individual with a skull length of 195 cm (6.40 ft), compared to the holotype's estimated at 1.80 m (5.9 ft) skull, making it likely that Giganotosaurus had the largest skull of any known theropod. Giganotosaurus surpassed Tyrannosaurus in mass by at least half a ton (the upper size estimate for T. rex is 9.1 t). Additionally several single teeth, discovered from 1987 onwards, have been referred to the species.

Posted Image

Tyrannosaurus rex
Tyrannosaurus is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex (rex meaning "king" in Latin), commonly abbreviated to T. rex, is a fixture in popular culture. It lived throughout what is now western North America, with a much wider range than other tyrannosaurids. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the upper Cretaceous Period, 67 to 65.5 million years ago. It was among the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event. Like other tyrannosaurids, Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to the large and powerful hindlimbs, Tyrannosaurus forelimbs were small, though unusually powerful for their size, and bore two clawed digits. Although other theropods rivaled or exceeded Tyrannosaurus rex in size, it was the largest known tyrannosaurid and one of the largest known land predators. By far the largest carnivore in its environment, Tyrannosaurus rex may have been an apex predator, preying upon hadrosaurs and ceratopsians, although some experts have suggested it was primarily a scavenger. The debate over Tyrannosaurus as apex predator or scavenger is among the longest running in paleontology. Tyrannosaurus rex was one of the largest land carnivores of all time; the largest complete specimen, FMNH PR2081 ("Sue"), measured 12.8 metres (42 ft) long, and was 4.0 metres (13.1 ft) tall at the hips. Mass estimates have varied widely over the years, from more than 7.2 metric tons (7.9 short tons), to less than 4.5 metric tons (5.0 short tons), with most modern estimates ranging between 5.4 and 6.8 metric tons (6.0 and 7.5 short tons). Packard et al. (2009) tested dinosaur mass estimation procedures on elephants and concluded that dinosaur estimations are flawed and produce over-estimations; thus, the weight of Tyrannosaurus could be much less than usually estimated. Other estimations have concluded that the largest known Tyrannosaurus specimens had a weight exceeding 9 tonnes.

Posted Image

______________________________________________________________________________


Prehistoric Cat
Jan 31 2012, 04:53 PM
Giganotosaurus VS Tyrannosaurus
Offline Profile Quote Post Goto Top
 
Replies:
Spinodontosaurus
Member Avatar
Herbivore
[ *  *  *  * ]
Based on Hartman's estimate that MUCPv-95 is only 6.5% larger than the type specimen, it and Sue have torso's of almost identical length, yet Sue's torso is clearly deeper overall and would be wider. No definite conclusions can be drawn about density because they haven't been directly compared; Giganotosaurus' hasn't even been estimated in the first place.
Offline Profile Quote Post Goto Top
 
theropod
Member Avatar
palaeontology, open source and survival enthusiast
[ *  *  *  *  *  *  *  * ]
We have a density estimate for FMNH PR 2081. We also have density estimates for Acrocanthosaurus atokensis and Allosaurus jimmadseni. Both are more than 12% higher than that of Sue. Just ignoring that is biased imo

The overall size of Giganotosaurus' torso at 8% bigger than MUCPv-CH1 is definitely larger than that in FMNH PR 2081, and due to being overally larger, I doubt it would be narrower in absolute terms, tough certainly compared to the lenght of the animal.
Assuming sue would be wider without having direct evidence and despite Giganotosaurus being overally larger is worse than assuming it would be less dense, don't you think so? Just as baseless as assuming because Giganotosaurus was larger it was likely also wider.

For the 8%, since we are still using Sue, not carnegii or some other moderate-sized specimen of Tyrannosaurus, I don't see a reason why we should resort to more conservative figures for the Giganotosaurus Holotype.
Offline Profile Quote Post Goto Top
 
Spinodontosaurus
Member Avatar
Herbivore
[ *  *  *  * ]
theropod
Jun 9 2013, 06:58 PM
We have a density estimate for FMNH PR 2081. We also have density estimates for Acrocanthosaurus atokensis and Allosaurus jimmadseni. Both are more than 12% higher than that of Sue. Just ignoring that is biased imo

The density for a single specimen has shown to vary hugely through even slightly different restoration techniques. Comparing densities achieved through different methods is no more valid than comparing weight estimates achieved through different methods (e.g. comparing Therrein and Henderson's 20 tonne Spinosaurus with Christiansen and Farina's 6.1 tonne Tyrannosaurus is completely meaningless).

Quote:
 
I don't see a reason why we should resort to more conservative figures for the Giganotosaurus Holotype.

Yet:
Quote:
 
The overall size of Giganotosaurus' torso at 8% bigger than MUCPv-CH1 is definitely larger than that in FMNH PR 2081

So, you see no reason to use conservative figures for one specimen - which is not at all what I am doing or even suggesting we do - but see it as perfectly fine to use liberal ones for another? Liberal estimates who's basis aren't even known at that.
We are using Scott Hartman's restoration of Giganotosaurus, so I highly advise we also use his estimate for MUCPv-95; ~6.5% larger than the type specimen.
And no, 6.5% is not a conservative figure, it is from probably the most reliable source, and certainly the most recent, and is thus the most reliable. 2.2% would be the conservative figure and, unlike with the 8% figure, it is clear what this estimate is derived from.

Quote:
 
Assuming sue would be wider without having direct evidence and despite Giganotosaurus being overally larger is worse than assuming it would be less dense, don't you think so?

No... the two things aren't even comparable.
We know from fossil evidence that Sue is broad-chested, more so than any carnosaur (as far as we know). Thus, we can infer that Sue would have been (significantly) wider than a Giganotosaurus of equivalent length (MUCPv-Ch1), and probably wider than a Giganotosaurus of equivalent torso length too (MUCPv-95).
We can go a step further and try to find rough estimates. Scaling Bates et al. 2009 Acrocanthosaurus to the same torso height as in Giganotosaurus yields a width of around 1.5 meters. Very rough figure, but clearly smaller than the 2 meter wide Sue.

We can say they are of roughly equal width (and depth) if you like, they are going to come out almost identical in size unless you deliberately try to make them otherwise.
Offline Profile Quote Post Goto Top
 
terminator
Autotrophic Organism
[ *  * ]
Gigs wins here due to size and power.
Offline Profile Quote Post Goto Top
 
theropod
Member Avatar
palaeontology, open source and survival enthusiast
[ *  *  *  *  *  *  *  * ]
Quote:
 
The density for a single specimen has shown to vary hugely through even slightly different restoration techniques. Comparing densities achieved through different methods is no more valid than comparing weight estimates achieved through different methods (e.g. comparing Therrein and Henderson's 20 tonne Spinosaurus with Christiansen and Farina's 6.1 tonne Tyrannosaurus is completely meaningless).
Doesn´t change the facts all the figures show all but one T. rex specimens are not as dense as the carnosaurs we have.

Quote:
 
So, you see no reason to use conservative figures for one specimen - which is not at all what I am doing or even suggesting we do - but see it as perfectly fine to use liberal ones for another?

Another? I don´t get what you mean.

Quote:
 
Liberal estimates who's basis aren't even known at that.
We are using Scott Hartman's restoration of Giganotosaurus, so I highly advise we also use his estimate for MUCPv-95; ~6.5% larger than the type specimen.
And no, 6.5% is not a conservative figure, it is from probably the most reliable source, and certainly the most recent, and is thus the most reliable. 2.2% would be the conservative figure and, unlike with the 8% figure, it is clear what this estimate is derived from.

Well, the only other source you could use would eb Greg Paul, whose skeletal would make Giganotosaurus a good deal larger still.
When I scaled it 8% fitted the size of the dentary perfectly. You are of course free to find the flaws this was caused by if they exist. Until then, when comparing it to FMNH PR 2081, I will trust what my own research suggests and see no reason to take the more conservative figures. However one thing is for sure, there is no basis for Giganotosaurus being the smaller animal here.

Quote:
 
We know from fossil evidence that Sue is broad-chested, more so than any carnosaur (as far as we know). Thus, we can infer that Sue would have been (significantly) wider than a Giganotosaurus of equivalent length (MUCPv-Ch1), and probably wider than a Giganotosaurus of equivalent torso length too (MUCPv-95).

And all carnosaurs we have comparable data of are denser than all but one T. rex. You chose to ignore that too.
The point is, Giganotosaurus has a bigger torso laterally, hence even tough sue is likely wider at parity, it is not necessarily wider in absolute terms.

Quote:
 
We can go a step further and try to find rough estimates. Scaling Bates et al. 2009 Acrocanthosaurus to the same torso height as in Giganotosaurus yields a width of around 1.5 meters. Very rough figure, but clearly smaller than the 2 meter wide Sue.

I hope you ignored the spines.
You also know sue has an inaccurately mounted ribcage, do you?

Offline Profile Quote Post Goto Top
 
Spinodontosaurus
Member Avatar
Herbivore
[ *  *  *  * ]
theropod
Jun 11 2013, 07:34 PM
Doesn´t change the facts all the figures show all but one T. rex specimens are not as dense as the carnosaurs we have.

When future studies test the animals together with the same method, then we can talk. Only Bates et al. has done this, and the density difference is minimal to say the least, to the point the 'alternate models' for each specimen have densities that vary just as much, if not more.

If you insist on comparing between different methods, you might as well do the same for weight estimates too, at which point you can make any large theropod you want appear the largest.

Quote:
 

Another? I don´t get what you mean.

MUCPv-95

Quote:
 
Well, the only other source you could use would eb Greg Paul, whose skeletal would make Giganotosaurus a good deal larger still.

Currie and Coria (2006); 12.2 meters.

Quote:
 
I will trust what my own research suggests and see no reason to take the more conservative figures.

And I see no reason to support your figure above Scott Hartman's.

Quote:
 
However one thing is for sure, there is no basis for Giganotosaurus being the smaller animal here.

I beg to differ.
Besides, this is not what I am saying is the case. I have been saying all along that they were probably comparable in size.

Quote:
 
And all carnosaurs we have comparable data of are denser than all but one T. rex. You chose to ignore that too.

No I didn't. I simply chose not to compare figures from different studies that used different methods and yielded wildly different results for the two specimens they both tested.

By the way, even if you change Bates et al.'s Stan to have a density as low as .73, it still comes out just as large as their Acrocanthosaurus (6177kg for both, incidently) which is of similar body size.

Quote:
 

I hope you ignored the spines.

Of course. You can try it yourself if you like.

Quote:
 
You also know sue has an inaccurately mounted ribcage, do you?

As does NCSM 14345.

[/quote]
Offline Profile Quote Post Goto Top
 
SpinoInWonderland
The madness has come back...
[ *  *  *  *  *  *  *  * ]
Can we just forget about FMNH PR2081 here, at least once! Why when you guys see "Tyrannosaurus", you think of FMNH PR2081! Let's try CM 9380 vs MUCP-Ch1...
Offline Profile Quote Post Goto Top
 
Jinfengopteryx
Member Avatar
Aspiring paleontologist, science enthusiast and armchair speculative fiction/evolution writer
[ *  *  *  *  *  *  *  * ]
Are you referring to Spinodontosaurus' statement of Giganotosaurus and Tyrannosaurus being comparable in size. Well, when taking your example, Giganotosaurus would be slightly longer in terms of length, but the volume could still be similar.
Offline Profile Quote Post Goto Top
 
theropod
Member Avatar
palaeontology, open source and survival enthusiast
[ *  *  *  *  *  *  *  * ]
Quote:
 
MUCPv-95

I was talking about that specimen in the first place.
Quote:
 
When future studies test the animals together with the same method, then we can talk. Only Bates et al. has done this, and the density difference is minimal to say the least, to the point the 'alternate models' for each specimen have densities that vary just as much, if not more.


Yes, because that was Stan, while the only study that tested it and sue together found sue to be much less dense.
I simply do not believe a sue-like T. rex was that much heavier than a carnosaur at similar lenghts, the density counteracts the more barrel-chested built.
Quote:
 
No I didn't. I simply chose not to compare figures from different studies that used different methods and yielded wildly different results for the two specimens they both tested.

But you DO compare ribcage widths from different mounts?

Quote:
 
By the way, even if you change Bates et al.'s Stan to have a density as low as .73, it still comes out just as large as their Acrocanthosaurus (6177kg for both, incidently) which is of similar body size.

Which is because their stan has this:
Posted Image
while their Acrocanthosaurus has this:
Posted Image
without even speaking of rib posture. And Acrocanthosaurus ridge is most likely not even properly filled in. This is the reason I think their Stan is far more overestimated than their Acrocanthosaurus.

Who sais the chest and pubis have to be connected in a straight line? Besides, they reconstructed a far greater amount of tissue below the ribcage in Stan than in Acro.

Quote:
 
And I see no reason to support your figure above Scott Hartman's.

You don't have to, but I have to right to do so.

Quote:
 
Currie and Coria (2006); 12.2 meters.

I was speaking of reconstructions. Currie & Coria, 2006 doesn't even have a metodology, and unless there is reason to suspect otherwise would simply be more short-tailed than Hartman's (not very elongate) version.

Quote:
 
Besides, this is not what I am saying is the case. I have been saying all along that they were probably comparable in size.

My bad. From your calculation in another thread i got the impression you were suggesting sue was the heavier of the two.
Offline Profile Quote Post Goto Top
 
Jinfengopteryx
Member Avatar
Aspiring paleontologist, science enthusiast and armchair speculative fiction/evolution writer
[ *  *  *  *  *  *  *  * ]
theropod
Jun 12 2013, 02:15 AM
I simply do not believe a sue-like T. rex was that much heavier than a carnosaur at similar lenghts, the density counteracts the more barrel-chested built.
The mass study is very widely known (and often cited), so I believe the scientists who claim that are aware of the lower density.
Offline Profile Quote Post Goto Top
 
Spinodontosaurus
Member Avatar
Herbivore
[ *  *  *  * ]
Quote:
 
Yes, because that was Stan, while the only study that tested it and sue together found sue to be much less dense.

Please don't make me repeat myself.

Quote:
 

But you DO compare ribcage widths from different mounts?

I can't tell whether you are grasping at straws or are actually presenting this seriously.
Did you miss the part where I only did this because you said "I doubt it [MUCPv-95] would be narrower in absolute terms"?
Quote:
 
Posted Image

What is the issue, exactly? Do you propose that they made the flesh hug the shape of the ribcage ala Greg Paul? You can take their lower bound estimate for Stan if you insist, but when you apply Hutchinson's .791 density for Sue, it still comes out as heavier than Acrocanthosaurus.

Either way, .73 is far lower than has ever been estimated for Sue.
Edited by Spinodontosaurus, Jun 12 2013, 03:05 AM.
Offline Profile Quote Post Goto Top
 
moldovan0731
Member Avatar
Heterotrophic Organism
[ *  *  * ]
Megafelis Fatalis
Jan 31 2012, 11:48 PM
Posted Image
This is the new version: http://www.commons.wikimedia.org/wiki/File:Giganotosaurus_and_Tyrannosaurus_size.jpg
Offline Profile Quote Post Goto Top
 
moldovan0731
Member Avatar
Heterotrophic Organism
[ *  *  * ]
I say Giganotosaurus 60%, Tyrannosaurus 40%
Edited by moldovan0731, Jul 11 2017, 12:59 AM.
Offline Profile Quote Post Goto Top
 
SpinoInWonderland
The madness has come back...
[ *  *  *  *  *  *  *  * ]
moldovan0731
Jun 12 2013, 03:58 AM
Megafelis Fatalis
Jan 31 2012, 11:48 PM
Posted Image
This is the new version: http://www.commons.wikimedia.org/wiki/File:Giganotosaurus_and_Tyrannosaurus_size.jpg
Both versions are inaccurate, this one is better: http://shartman.deviantart.com/art/North-vs-South-Giant-theropod-square-off-361721772
Offline Profile Quote Post Goto Top
 
Big G
Herbivore
[ *  *  *  * ]
brolyeuphyfusion
Jun 12 2013, 04:04 AM
moldovan0731
Jun 12 2013, 03:58 AM
Megafelis Fatalis
Jan 31 2012, 11:48 PM
Posted Image
This is the new version: http://www.commons.wikimedia.org/wiki/File:Giganotosaurus_and_Tyrannosaurus_size.jpg
Both versions are inaccurate, this one is better: http://shartman.deviantart.com/art/North-vs-South-Giant-theropod-square-off-361721772
Actually, I do not think MUPCv-95 was 13.2 meters. I think that the first specimen was about 12.5-13 meters and the second approximately around 13.5+ meters.
Edited by Big G, Jun 12 2013, 04:14 AM.
Offline Profile Quote Post Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
Go to Next Page
« Previous Topic · Dinosauria Interspecific Conflict · Next Topic »
Add Reply

Find this theme on Forum2Forum.net & ZNR exclusively.