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Post by Grey on Nov 19, 2014 23:21:07 GMT 5
So one Mapusaurus specimen is potentially the largest carnivorous dinosaur ? This would suggest a 9 300 kg beast, almost one ton heavier than Sue.
I like the new Spinosaurus but isn't it supposed to be even a bit more shallower in body depth ?
Ibrahim et al. says "more than 15 m", I think 16 m is accurate enough, that's the size of the life-size Geomodel based on the team's works.
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gigadino96
Junior Member
Vi ravviso, o luoghi ameni
Posts: 226 
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Post by gigadino96 on Nov 20, 2014 0:46:23 GMT 5
So one Mapusaurus specimen is potentially the largest carnivorous dinosaur ? This would suggest a 9 300 kg beast, almost one ton heavier than Sue. I like the new Spinosaurus but isn't it supposed to be even a bit more shallower in body depth ? Ibrahim et al. says "more than 15 m", I think 16 m is accurate enough, that's the size of the life-size Geomodel based on the team's works. Yes, that Mapusaurus is pretty freakish, if it was really that big (even though I got 8,900 kg scaling from MUPCv-ch1), but we're speaking about a specimen. Most of the adult Mapusaurus specimens are actually between 12 and 13 m, so similar in size to the know Giganotosaurus and Carcharodontosaurus specimens. So it's likely that even its relatives got that big. Or at least that's just my opinion. I'd treat the giant Carcharodontosaurids and Tyrannosaurus rex as the same size. That skeletal was made by Myess, you could ask him. I've read somewhere that Ibrahim said that Spinosaurus was around to 50 feet, I don't exactly remember where. However, cau said that MSNM V4047 would be at most 14-15 m, if it was really that big, so I used his estimate. |
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Post by Grey on Nov 20, 2014 2:22:16 GMT 5
Where is the mention of that Mapusaurus specimen ? Isn't that bone supposed to be also more gracile than in Giganotosaurus ? If so, I'd the reconstruction with a Giga based body is somewhat off.
Yes, it's safe to say that on a general basis the largest tyrannosaurids and carcharodontosaurids are about the same size. But if there is one individual among them that we know to surpass the others, it's reasonnable to temporarily suggest the corresponding species as the largest. If this Mapusaurus was indeed 10 % larger than the Giganotosaurus type and that we can assume isometric scaling from it, that's quite a monster. Where comes from the skull depiction ?
I've scaled the body mass using Hartman estimate of 6 800 kg for MUPCv-ch1.
Who's Myess ?
In the paper, it's said more than 15 m and I think that spinodontosaurus deduced that the measurement was made along the curve or something. But that overall it corresponds to 16 m.
I think though the Spinosaurus should be a bit shallower in the chest looking at the torso from Ibrahim et al.
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Post by theropod on Nov 20, 2014 3:16:22 GMT 5
It’s a pubic shaft, described in the same place where all the other Mapusaurus individuals are described (nothing new, I’ve been including it for years now), and the compared measurements are actually width/thickness, so in case the bone was more gracile the above reconstruction is too conservative and should be larger, but that’s baseless speculation. The evidence for Mapusaurus actually being more gracile being little more than media hogwash and at best based on individuals of different sizes and states of maturity, or a fibula (which is worth very little, being more or less vestigial in some animals than in others and bearing little weight at best. At the same time, the tibia of Mapusaurus seems very robust, but there’s not really a basis for comparison here.). Of course having the biggest specimen isn’t the same as being the biggest species, just containing the largest currently known individual. spinodontosaurus concluded it’s most likely NOT measured along the curves, meaning while standing lenght may be closer to 15m, total lenght as measured in theropods would be closer to 16m. Btw the chest is still extremely incomplete. There seem to be just two actual complete ribs of Spinosaurus in the composite, one of them being the original holotypic one. But I think with the new data out now Miyess’ skeletal will need some updates in the proportions department regardless, as it was done before Ibrahim et al. published their results. For what it’s worth I measured the skeletal in question based on the lenght of the rostrum and I seem to recall it ended up almost exactly the same lenght as Hartman’s, but someone should verify that.
References: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 Ibrahim, Nizar; Sereno, Paul C.; Dal Sasso, Christiano; Maganuco, Simone; Fabbri, Matteo; Martill, David M.; Zouhri, Samir; Myhrvold, Nathan P.; Iurino, Dawid A.: Semiaquatic Adaptions in a Giant Predatory Dinosaur. Science, Vol. 345 (2014); No. 6204; pp. 1613-1616 miyess.deviantart.com/art/Spinosaurus-Revised-479151633 |
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Post by Grey on Nov 20, 2014 3:30:55 GMT 5
So this Mapusaurus individual is really potentially bigger than Giganotosaurus (and Tyrannosaurus ?) specimens ?
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Post by theropod on Nov 20, 2014 3:34:37 GMT 5
Of course it is.
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Post by Grey on Nov 20, 2014 3:39:32 GMT 5
And using a Giga based body is reasonnable enough ? What about the initial body reconstruction of Mapusaurus ?
How large would be that skull ?
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Post by spinodontosaurus on Nov 20, 2014 4:44:25 GMT 5
The keyword here is 'potentially'. It's a fragment of the pubic shaft that is all of a couple of millimeters larger than in Giganotosaurus.
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Post by Grey on Nov 20, 2014 4:52:30 GMT 5
The keyword here is 'potentially'. It's a fragment of the pubic shaft that is all of a couple of millimeters larger than in Giganotosaurus. All in all, if one takes all the giants theropods individuals known by only even fragments, which one is 'potentially' the largest (heaviest) ? I mean using all the available data ? That Mapusaurus individual ? |
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stomatopod
Junior Member
Gluttonous Auchenipterid
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Post by stomatopod on Nov 20, 2014 6:25:17 GMT 5
Eithet that Mapusaurus or UCMP 137538.
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Post by theropod on Nov 20, 2014 11:09:21 GMT 5
And using a Giga based body is reasonnable enough ? What about the initial body reconstruction of Mapusaurus ? How large would be that skull ? What initial body reconstruction of Mapusaurus? There is no such thing. Basing it on G. carolinii is currently the most reasonable thing to do. For all we know its skull would also be comparable to Giganotosaurus'. I've got an rxtrapolation for the largest Mapusaurus included in my skull diagram for that taxon, the figure basing on the upper estimate for Giganotosaurus. |
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Post by theropod on Nov 20, 2014 11:12:28 GMT 5
Yup, it's possible UCMP 137538 is an IV-2, making it a 14.4m monstrosity. Of course, it's statistically more likely that it isn't.
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Post by Grey on Nov 20, 2014 12:08:20 GMT 5
And using a Giga based body is reasonnable enough ? What about the initial body reconstruction of Mapusaurus ? How large would be that skull ? What initial body reconstruction of Mapusaurus? There is no such thing. Basing it on G. carolinii is currently the most reasonable thing to do. For all we know its skull would also be comparable to Giganotosaurus'. I've got an rxtrapolation for the largest Mapusaurus included in my skull diagram for that taxon, the figure basing on the upper estimate for Giganotosaurus. That one www.dinosoria.com/lexique_espece/mapu_reconstitution.jpgThe largest reasonnably complete individual, the one comparable in size to Giga's type, is no more slender than it by comparison ? You refer to that reconstruction of your I guess : upload.wikimedia.org/wikipedia/commons/7/73/Mapusaurus-skull-comparison.jpg |
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Post by theropod on Nov 20, 2014 17:14:27 GMT 5
What initial body reconstruction of Mapusaurus? There is no such thing. Basing it on G. carolinii is currently the most reasonable thing to do. For all we know its skull would also be comparable to Giganotosaurus'. I've got an rxtrapolation for the largest Mapusaurus included in my skull diagram for that taxon, the figure basing on the upper estimate for Giganotosaurus. That one www.dinosoria.com/lexique_espece/mapu_reconstitution.jpgThe largest reasonnably complete individual, the one comparable in size to Giga's type, is no more slender than it by comparison ? You refer to that reconstruction of your I guess : upload.wikimedia.org/wikipedia/commons/7/73/Mapusaurus-skull-comparison.jpgThat's no official reconstruction, and seems quite inaccurate. There is no reasonably complete Mapusaurus individual, let alone one exactly the same size as MUCPv-ch1, because the remains are disarticulated. The myth that it was more slender may have come from the big fibula that's longer but more gracile than Giganotosaurus', but that's obviously not compelling. Yes, that one. The ghost outline is an extrapolation for the specimen in question. |
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Post by theropod on Nov 20, 2014 17:20:01 GMT 5
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