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Post by Godzillasaurus on Feb 11, 2011 1:21:55 GMT
Hey when did Carcharodontosaurus out grow Giganotosaurus?? Have we found new material?? The Wikipedia say's that There is some new information on the species C. iguidensis. What differs it from C. saharicus? Just the Maxilla and brain case? are these valid differences??
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Post by eriorguez on Feb 11, 2011 2:05:04 GMT
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Post by DinoLord on Feb 11, 2011 2:09:17 GMT
Ah Eriorguez, I think you will greatly enjoy the debates here.
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Post by Horridus on Feb 11, 2011 2:11:34 GMT
I love the title of that paper ;D
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Post by eriorguez on Feb 11, 2011 2:15:15 GMT
The trouble is that including Spinosaurus on a chart consisting of "actual remains" means that it'll just be a head and some vertebrae... The second specimen of Giganotosaurus is a single bone. The holotype is smaller that Sue. All basis for Allosaurus being at the 12 meter range are some vertebrae. Spinosaurus is far more complete that MANY dinosaurs, and its sheer size is clear, even incomplete. To say nothing that we happen to be quite good at making estimates; Sue had the exact proportions that we'd expect from a 13 meter Tyrannosaurus, and had 2 fingers. Just like we expected from seeing Gorgosaurus skeletons, and the far less complete specimens of Tyrannosaurus we had.
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Post by Himmapaan on Feb 11, 2011 2:15:56 GMT
Ah Eriorguez, I think you will greatly enjoy the debates here. Oh, dear; how ominous that sounds. ;D
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Post by Horridus on Feb 11, 2011 2:18:01 GMT
The trouble is that including Spinosaurus on a chart consisting of "actual remains" means that it'll just be a head and some vertebrae... The second specimen of Giganotosaurus is a single bone. The holotype is smaller that Sue. All basis for Allosaurus being at the 12 meter range are some vertebrae. Spinosaurus is far more complete that MANY dinosaurs, and its sheer size is clear, even incomplete. To say nothing that we happen to be quite good at making estimates; Sue had the exact proportions that we'd expect from a 13 meter Tyrannosaurus, and had 2 fingers. Just like we expected from seeing Gorgosaurus skeletons, and the far less complete specimens of Tyrannosaurus we had. I'm aware of this; what I mean is that it can be misleading for members of the public to be led to believe that dinosaurs are ALWAYS known from very complete remains, which is a popular misconception. More specifically for the above quote (I'm tired ) I was using Spinosaurus as an example of how a chart would look based on "actual remains". OF COURSE it is possible to extrapolate, with reasonable accuracy, and calculate the size of the whole animal, and that is what is needed to produce these charts!
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Post by eriorguez on Feb 11, 2011 2:34:07 GMT
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Post by Horridus on Feb 11, 2011 2:40:18 GMT
But remember that EVERY dinosaur is a reconstruction, and Tyrannosaurus is not far more accurate that Spinosaurus in those charts. Of course, although Tyrannosaurus is far better known that Spinosaurus in reality (sheer number of specimens, with a small number of relatively complete specimens). Scott Hartman's chart is a good 'un, and Paul's are very similar. Having visited the Natural History Museum in London since childhood, it's interesting to note how much lower the skull of Baryonyx is now restored when compared with the (now rather old) mount in the museum.
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Post by foxilized on Feb 11, 2011 4:45:28 GMT
So I'll just shut up and accept what exist. No, don't do that! You are quite right in saying that it's important to point out to people what's speculative, and based on other animals. I meant I'll stop complaining on someone's elses work when I am not doing any better. Complaining is just too easy.
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Post by Megaraptor on Feb 11, 2011 6:09:34 GMT
The trouble is that including Spinosaurus on a chart consisting of "actual remains" means that it'll just be a head and some vertebrae... The second specimen of Giganotosaurus is a single bone. The holotype is smaller that Sue. All basis for Allosaurus being at the 12 meter range are some vertebrae. Spinosaurus is far more complete that MANY dinosaurs, and its sheer size is clear, even incomplete. To say nothing that we happen to be quite good at making estimates; Sue had the exact proportions that we'd expect from a 13 meter Tyrannosaurus, and had 2 fingers. Just like we expected from seeing Gorgosaurus skeletons, and the far less complete specimens of Tyrannosaurus we had. Ah, been wondering when you'd show up here, Eriorguez. And yes, we are very good at making estimates. And also, the basis for Allosaurus being 12 metres long is a dinosaur called Epanterias which is nowdays considered a species of Allosaurus. Wait, Epanterias is the vertebrae you're referring to.
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Post by Horridus on Feb 11, 2011 16:05:00 GMT
Saurophaganax maximus, aka Allosaurus maximus, is another very large Morrison allosaur (although not quite as large as Epanterias).
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Post by eriorguez on Feb 11, 2011 16:48:24 GMT
Yup, but it is kept by most reviews as separate from Allosaurus, while Epanterias is deemed a synonim of Allosaurus fragilis.
And Tom Holtz puts Saurophaganax as slighty larger that Allosaurus, even counting AMNH 5767.
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Post by Horridus on Feb 11, 2011 17:07:56 GMT
I suppose it really depends on where you draw the line at generic level; for example Paul lumps Saurophaganax into Allosaurus, but he's known as a zealous lumper. As you say, majority opinion seems to be in favour of splitting. I think Paul's rationale tends to be based on the inclusiveness of many modern genera.
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Post by eriorguez on Feb 11, 2011 19:13:53 GMT
Yup, but some modern genera are either...
A) MASSIVELY overlumped. Varanus, for example. B) Quite constrained in time, not spaning million of years. and C) Subjective. That's the most important thing to remember, genera are subjective groups. In different groups the custom is different.
Seeing his post in the DML, Paul didn't seem like he got the memo.
And Monolophosaurus looks nothing like Dilong. Meanwhile, he kept the different Leptoceratopsids as separate, yet all of them are more similar to each other that Giganotosaurus and Carcharodontosaurus (and Mapusaurus, far more similar to Giga, remained separate).
Paul failed hard in his lumping. HARD. And that is coming from a lumper prone to exclaim "individual variation".
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Post by Horridus on Feb 11, 2011 19:27:18 GMT
Wasn't it Monolophosaurus and Guanlong that were lumped? But yeah, a lot of it is very dubious (see also: hadrosaurs). Quite ironic, though, that he eventually was proven 'right' on the, er, split of "Brachiosaurus" brancai! ;D
Re Varanus, did you see Darren Naish's blog post on taxonomy that mentioned it?
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Post by eriorguez on Feb 11, 2011 23:20:19 GMT
Agh, I cannot remember the names of the -long dinosaurs, they are too short to get a clear difference! And I think so, can't recall right now, but yeah, tradition and genera not being "real" things, just tools in clasification.
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Post by Horridus on Feb 12, 2011 3:05:38 GMT
Of course - some people argue that specification is only 'real' at the specific level - and some people argue that things are only real at INDIVIDUAL level! By the way, you should introduce yourself in the New Members thread, you seem like quite a character. My own brief bio is available at www.dinotoyblog.com/about-the-authors/
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Post by eriorguez on Feb 12, 2011 4:42:33 GMT
Heh, Occam already said that there is no such thing as "chairs", only different pieces of furniture used to sit on that get thrown together in a cathegory. Species is not more special that any other clade; take a look at the brown bear, the American populations are closer phylogenetically to the polar bear, but anatomically and behaviour-wise, they are more similar to the Eurasian populations, to a point that you cannot have Ursus arctos without U.maritimus inside. There is no such thing as species, it is only a collection of populations, which are a bunch of individuals. Populations are a better basic unit of taxonomy, but, once you factor time, things get weird. Mmm, an intro? Give me a bit of time, so I can get to know the comunity and be more jovial.
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Post by lio99 on Feb 23, 2011 4:36:54 GMT
T-rex was not longer than the three but it was taller.
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