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Spinosaurus aegyptiacus v Tyrannosaurus rex
Topic Started: Jan 7 2012, 02:16 AM (459,363 Views)
Wolf Eagle
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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.[1] 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.

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Spinosaurus aegyptiacus
Spinosaurus is a genus of theropod dinosaur which lived in what is now North Africa, from the lower Albian to lower Cenomanian stages of the Cretaceous period, about 112 to 97 million years ago. Spinosaurus may be the largest of all known carnivorous dinosaurs, even larger than Tyrannosaurus and Giganotosaurus. Estimates published in 2005 and 2007 suggest that it was 12.6 to 18 metres (41 to 59 ft) in length and 7 to 20.9 tonnes (7.7 to 23.0 short tons) in weight. The skull of Spinosaurus was long and narrow like that of a modern crocodilian. Spinosaurus is thought to have eaten fish; evidence suggests that it lived both on land and in water like a modern crocodilian. The distinctive spines of Spinosaurus, which were long extensions of the vertebrae, grew to at least 1.65 meters (5.4 ft) long and were likely to have had skin connecting them, forming a sail-like structure, although some authors have suggested that the spines were covered in fat and formed a hump. Multiple functions have been put forward for this structure, including thermoregulation and display. Dal Sasso et al. (2005) assumed that Spinosaurus and Suchomimus had the same body proportions in relation to their skull lengths, and thereby calculated that Spinosaurus was 16 to 18 meters (52 to 59 ft) in length and 7 to 9 tonnes (7.7 to 9.9 short tons) in weight. The Dal Sasso et al. estimates were criticized because the skull length estimate was uncertain, and (assuming that body mass increases as the cube of body length) scaling Suchomimus which was 11 meters (36 ft) long and 3.8 tonnes (4.2 short tons) in mass to the range of estimated lengths of Spinosaurus would produce an estimated body mass of 11.7 to 16.7 tonnes (12.9 to 18.4 short tons).

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Edited by Taipan, Apr 24 2015, 10:10 PM.
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TheROC
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Quote:
 
There's NO Spino's specimen with a 2m long skull, give me a source claim that


For future reference, I do hope you realize that this is not a particular bright approach to opening a discussion.

Prematurely refute something as existing, and then asking for evidence that it exists--Which is to say is a blatant contradiction in an admittance of uncertainty, following a statement denoting strength of certainty.

If you are not aware of something, simply say so. Do not open a post with a negative modifier with certainty when you aren't certain.

As I said, Horner has referred to several times in the past, a [private specimen] very large dentary that would amount to coming from an over 2 meter skull. He referred to it even as recent as 2007 in an interview with Dan Schneider here, which is of course 2 years after the initial Dal Sasso et al findings and papers. Also, ask Grey for more information, but within this same thread in page 5 or so, he had correspondence with Horner in which he asked for more information regarding the skull estimate he gave and Horner elaborated that he had seen a commercially collected 4 foot dentary that when combined with the surangular would make for a 2.4 meter skull.

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If you think that Spinosaurus has proportionately large head, tell that to Hartman, i didn't make those skeletal reconstruction.


I don't follow the point you're attempting make here--It wasn't a complaint towards Hartman, it was a correction on your behalf on thinking an animal was oversized in a reconstruction when referring to skull size within the reconstruction as an indicator. It wasn't a difficult to comprehend post--what with my reference to other Spinosaurus' specimens and all--that I was actually endorsing Hartman's proportions. His proportions also line up with the skull size estimate for the holotype, which is what he was originally attempting to show.

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Base on Hartman reconstruction, a 17m long Spino seems to be extremely unlikely.


Not at all. Put the the reconstructions side by side and you see that the 17 meter Spinosaurus' femur, tibia and fibula are all significantly larger than those of the three theropods closest to it in size. So in absolute terms, it is significantly larger--in proportional terms it is a bit more slender, but its bones are also less pneumatized than other large theropods, and secondly, it was a bit more lightly built in overall shape regardless. Secondly, another thing Hartman's skeletal does that would improve the weight bearing stress limitations in theropods is that his Spinosaurus has proportionately shorter legs than smaller Spinosaurids are reconstructed to have.

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Spino doesn't buit to support heavy weight, please read my reply carefully


Well no, there wasn't any particular substance within the post that called for more introspection I'm afraid. You just reached an arbitrary conclusion on stress limitations of the biomechanics in question here, without any more formal or intimate knowledge on the subject.

That more or less goes for everyone here of course. We have inferences to make, and little more than that without formal knowledge and expertise
Edited by TheROC, Aug 30 2012, 02:54 PM.
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theropod
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"Spino wasn´t built to support heavy weight" is premature, as you don´t have a clue to what individual the lags belong.

TheROC: what I meant was that it was elongated, probably when scaling it without keeping the ratio. look at the skull, there you can see it
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Verdugo
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Jinfengopteryx
Aug 4 2012, 12:10 AM
ArachnidKid
Jul 22 2012, 06:42 AM
bite,I.Q.,eye sight
Better Bite=Yes
Better IQ=Yes
Better vision=it doesn't look like only Tyrannosaurus has binuclear vision: http://upload.wikimedia.org/wikipedia/commons/4/46/Suchomimus_skeleton.jpg

If Suchomimus, why not Spino?
Actually, Suchomimus has no binocular vision. Take a look at this:

Tarbosaurus, an animal is considered to be lacked of binocular vision

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You can see that Tarbo has thin snout and wide skull, but it's still quite lack of binocular vision because the long snout block it sight

Suchomimus, an animal you considered to has good binocular vision:

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You can see that Suchomimus actually has much thinner skull relative to snout than Tarbosaurus, the snout is far longer proportionately than that of Tarbosaurus.

If Tarbosaurus is lacked of binocular vision, Suchomimus has NONE !!

You guys are biased here, not Prehistoric Cat. You guys are fanboys, not Prehistoric Cat. And i will never try to discuss with Spino fanboys, why ? because Spino fanboys has claimed that Spino is a 20m + monster and has a bite force surpasses Predator X lol lol lol
Edited by Verdugo, Sep 1 2012, 12:28 AM.
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theropod
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there are more factors in stereoscopic vision than just the dorsal or ventral shape of the skull, this largely depends on the position and size of the lacrimals, nasals and maxilla. and may I ask for a source that states tarbosaurus lacked binocular vision?

really, reading someone claiming the ones supporting the spinosaurus to be fanboys is just making me laugh.
You have ignored the proportions other spinosaurs had. You are claiming tons of unconfirmed/rumoured/made up T. rex specimens to be larger than sue, while none of them actually are...
Be careful when claiming other people to be fanboys
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Verdugo
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theropod
Sep 1 2012, 12:44 AM
there are more factors in stereoscopic vision than just the dorsal or ventral shape of the skull, this largely depends on the position and size of the lacrimals, nasals and maxilla. and may I ask for a source that states tarbosaurus lacked binocular vision?

really, reading someone claiming the ones supporting the spinosaurus to be fanboys is just making me laugh.
You have ignored the proportions other spinosaurs had. You are claiming tons of unconfirmed/rumoured/made up T. rex specimens to be larger than sue, while none of them actually are...
Be careful when claiming other people to be fanboys
_ Really ??. So can you tell me the position, size of Suchomimus's lacrimals, nasals and maxilla that gives Sucho binocular vision ???

_ Tarbosaurus Wikipedia !!.
http://en.wikipedia.org/wiki/Tarbosaurus

Part: "Description"
Seriously ?. You don't know this, it's so obvious  :-/

_ Give me a proof evidence that claimed MOR 008 is smaller than Sue !!. If you don't have any, i fully willing to believe that you're Spino's fanboy, because you want to make T rex smaller, weaker, more stupid,... to make YOUR Spino become the "undisputed king of all carnovores" (another fanboys claimed, not in this 4rum)

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SpinoInWonderland
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Can't people just accept the fact that Tyrannosaurus isn't the most powerful theropod there is?
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theropod
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I can show you images in frontal viwe that show it to have forward facing eyes, but in the end most of suchomimus skull wasn´t found.
Also, binocular vision is not just there or it´s not, it is often present to a varying degree (depending on how large the field in which the visual fields of the two eyes overlap). but it seriously isn´t as important as some people make it to be

MOR 008 was said to have a 1,5m skull but significantly smaller maxilla and dentary, thus Io think it is the mandible lenght like it was often confused with the skull lenght in sue as well (in her it´s 1,54m, so MOR ends up smaller like it should be regarding the size of the parts we know). furthermore the skull was reconstructed.

The rest is ridiculous and I won´t bother answering to it.
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theropod
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and a 2,4m spinosaurus skull hasn´t less credential than MOR being larger than sue for sure. then you should try scaling scott hartmans and another spinosaurus skeletal (one that´s closer to the correct rtio indicated by it´s relatives) to that skull size and scaling T. rex to 1,5m. you´ll see, Spinosaurus will be even much bigger than 18 vs 12,3m
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7Alx
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Spinosaurus couldn't be much bigger than 18 m in length (for example 24 m) If it was 20+ tons, it must be quadruped, because being bipedal it wouldn't keep balance due that mass. Also it would need that many food for survive. But it would doubtful. I AM NOT AGAINST THAT SPINOSAURUS WAS MOST LIKELY THE LARGEST THEROPOD, but it can't be twice as big as other giant theropods like Carcharodontosaurus. Carcharodontosaurids stop growing at around 13 m, maybe 14-15 m cuz they still wanted to be active hunters. Pure scavenging isn't good strategy for land giant carnivores, it wouldn't found enough food for survive.
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Verdugo
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theropod
Sep 1 2012, 01:30 AM
I can show you images in frontal viwe that show it to have forward facing eyes, but in the end most of suchomimus skull wasn´t found.
Also, binocular vision is not just there or it´s not, it is often present to a varying degree (depending on how large the field in which the visual fields of the two eyes overlap). but it seriously isn´t as important as some people make it to be

MOR 008 was said to have a 1,5m skull but significantly smaller maxilla and dentary, thus Io think it is the mandible lenght like it was often confused with the skull lenght in sue as well (in her it´s 1,54m, so MOR ends up smaller like it should be regarding the size of the parts we know). furthermore the skull was reconstructed.

The rest is ridiculous and I won´t bother answering to it.
_ Yes, i have seen Sucho's skull frontal view but its eyes don't face forward a lot like you think. Sucho should only have none or a very slight degree of binocular vision

_ Seriously, binocular vision is not important ???. Imaging you and i without binocular vision lol

_ DIFFERENT T rex has DIFFERENT proportion of their skull. You cannot use a part of skull to scale up the size of the skull. You just need to read this
"Different Tyrannosaur skulls have different proportions. Just cause one part is bigger doesn't mean this holds true for the entire skeleton. Despite MOR 008 having a bigger skull, it's maxilla isn't as big as FMNH PR 2081." --- From Michael Mortimer

_ Agains, who claimed that 2,4m long skull ?. Horner ??. So you really trust him ??. Horner has made many claims that were proven to be inaccurate, like the famous: "T rex predator or scavenger". And most of his arguments to prove T rex is a scavenger has turned out to be completely wrong. In short, i cannot trust Horner, you need a more reliable source or proof evidence for this
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theropod
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-a bit of binocular vision is enough, and that´s all that I agrued
-close one eye, and you´ll still be able to hit an opponent. crocs are surviving without binocular vision for a very long time now, and they are particuarily reliant on landing a fast and secure bite
-Yes, but MOR 008 was RESTORED, and at least two elements that have been found are far smaller than in sue. so it could have either been restored the wrong way to maake it bigger (something pretty common in theropods), exagerated in size (or has mortimer examined the specimen?), or is basing simply on a confusing of mandible and skull lenght (like it can be seen in sue). Everything is pointing out to one of these, and there is hardly one way to invalidate a specimen being larger that has not already occured in T. rex specimens
-if you don´t believe that, your problem. but you believe a bunch of crap about unconfirmed T. rex specimens larger than sue, so you can just as well believe this unconfirmed report.
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Jinfengopteryx
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7Alx
Sep 1 2012, 02:33 AM
Spinosaurus couldn't be much bigger than 18 m in length (for example 24 m) If it was 20+ tons, it must be quadruped, because being bipedal it wouldn't keep balance due that mass.
Some people are seriosly suggesting that!
Edited by Jinfengopteryx, Sep 1 2012, 03:32 AM.
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Jinfengopteryx
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As far as I know, MOR 008 is quite fragmentary, still, it is always described as largest T rex skull in the world:
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Museum unveils world's largest T-rex skull
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Measuring 5 feet across, a T. rex skull found 40 years ago in Montana is the world´s largest T. rex skull. The specimen is now on display at the Museum of the Rockies at MSU. (Museum of the Rockies photos by John Little)
The world's largest Tyrannosaurus rex skull, unearthed nearly 40 years ago in eastern Montana, is now on display at the Museum of the Rockies at Montana State University in Bozeman.


The skull measures 5 feet long, making it bigger than the previous record-holder--the T-rex named "Sue" at Chicago's Field Museum, according to Jack Horner, the Museum's curator of paleontology. Skull fragments from the specimen, known as MOR 008, were found in the Hell Creek Formation near Billings in the late 1960s and collected by Bill McMannis, an MSU geologist. Museum preparator Carrie Ancell began their reconstruction in the late 1980s, and preparator Michael Holland finished the job this year. A single vertebra is the only other piece of MOR 008 that has been found besides the skull. "We are going to try and figure out how old the animal was when it died by using histology, the study of the microscopic structure of fossil remains," Horner said. "The specimen contains several characteristics that suggest this individual was mature, and perhaps quite old when it died." Horner said research on the specimen will continue. MOR 008 is one of three T-rex skulls in the Museum of the Rockies collection, all of which are on display in the Hall of Horns and Teeth. All of them were found in Montana. The Museum has part of twelve T-rexes, more than any other institution in the world. The Museum of the Rockies is open from 9 to 5, Monday through Saturday, and 12:30 p.m. to 5 p.m. on Sundays through May 26. Summer hours begin May 27 when the Museum will be open from 8 a.m. to 8 p.m. daily through Labor Day.

From that paper: phys.org/pdf63641065.pdf
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theropod
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I would not be that sure about it then, as this clearly shows it was reconstructed.
the proportions look odd as well, it seems as if jugal and postorbital had been made thicker than they should be, and if that part was reconstructed, it would make the skull too long.
The posterior portion is also strange.

Overall 1,5m being the accurate skull lenght of this specimen is very doubtful imo. (this )
Edited by theropod, Sep 1 2012, 04:02 AM.
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Jinfengopteryx
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Well, it must be based on something.
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