Size comparison scale

[spinodontosaurus]

Scott Hartman posted this on his Facebook page a couple of hours ago.

[Fragillimus335]

May 31, 2013 22:56:49 GMT 5 stomatopod said:

May 31, 2013 22:06:05 GMT 5 theropod said:

Taipan is that childish, he also created a fake account to have a reason to ban him. I doubt Paul's estimate is published, at least not in a paper. However if I remember right, Paul based that on different estimations for the vertebra's height, didn't he?

I do not understand why Taipan should have made a fake account, his old account was suspended, and new (double) accounts are clearly disallowed.

On Amphicoelias: Its neural arch nicely fits intoa ~40-45 meter Apatosaurus, which would have weighed about 80 tons. An Apatosaurus like bauplan is supported by phylogeny, a Diplodocus or Barosaurus like bauplan is not supported. (Also GSP recently said that he thinks that Amphicoelias is related to Apatosaurus. I have done similar calculatiuons supported by phylogeny and the outcome was always aroundd the same.
The only whay to get those high results is to use Taxa that have a higher torso lenght/D10 height ratio. Those taxa show an torso elongation in comparision with more basal forms, and using them is not supported by phylogeny.

In other words: Estimates that are in line with the phylogentic position of A. fragillimus rougly cluster around 40 meters and 80 tons, not accounting for supposed increased pheumatisation.



Another note that people should finally understand: Carpenter NEVER used Diplodocus as a direct proxy for A. fragillimus. Its nowhere in his paper(I have demonstrated this on CF).
He simply uses Diplodocus outline because it was the easiest choice.

What characters are you using for your non published ranking as an Apatosaurinae? You're doing full-blown character analysis? Even professional paleontologists can't get those right half the time.


And scaling from Apatosaurus gives 93-133 tons, not 80. Also, if we assume Apatosaur-style proportions, we would have to assume the vertebra would have much taller neural spines. BTW Scaling from A. ajax gives 58 meters and 230+ tons...so yeah.


And yes, yes he absolutely did. You have to be blind to miss it.

[theropod]

Jun 1, 2013 0:47:01 GMT 5 spinodontosaurus said:

Scott Hartman posted this on his Facebook page a couple of hours ago.

Amazing comparison, how come its not on deviantart yet?

[Dakotaraptor]

Epanterias(?=Allosaurus) vs Acrocanthosaurus

[theropod]

How did you scale them?

[spinodontosaurus]

Probably to the longest point of the Coracoid.
I just tried the same and got a standing length (i.e. not over the curves) of ~11.1 meters and hip height of ~3.1 meters using UUVP 6000.
Using MOR 693 ('Big Al') yields a standing length of ~10.6 meters but a virtually identical hip height.

The length difference is mainly down to tail length though, like so.

Full size version

[stomatopod]

What characters are you using for your non published ranking as an Apatosaurinae? You're doing full-blown character analysis? Even professional paleontologists can't get those right half the time.

I am using the results of Andrea Cau. Oh, and his phylogentic analyses are well acclaimed, just before you call his expertise into doubt.
Also, the result does notindicate that that it was in a close relationship with Apatosaurus, the closest position that was possible is basal to Flageellicaudata, hence I used both Amargasaurus and Apatosaurs(as a rather basal member).
I also see no indication that professional have problems with doing character analyses on such a big scale, but this might have been some hyperbole from your side.
Anyway, phylogentic analyses are far better than personal interpretation.

And scaling from Apatosaurus gives 93-133 tons, not 80. Also, if we assume Apatosaur-style proportions, we would have to assume the vertebra would have much taller neural spines. BTW Scaling from A. ajax gives 58 meters and 230+ tons...so yeah.

Which specimen do you use? And, no we do not have to assume that it would have a taller spinous process, as this in not indicated by its morphology. We also would have to assume the neural arch to look different, but it isn´t. Also, the spinous process of Apatosaurus is pretty straight while the one of Diplodocus is a little bit kinked forward. Taking this into account, the spinous process is longer by about 10 percent, which is, given the low sampling size of this comparision is, statitically nearly irrelevant.

Here is what I wrote on CF: "Ok here they are, I based them on the ratio of total vertebral height to precaudal/dorsal lenght, the first number is assuming a 2.7 meter vertebral height, the second assuming a 2.4 meter vertebral height:
Based on Haplocanthosaurus: Precaudal: 21,6/19,2 Trunk: 9,45/8,4
Based on Limaysaurus: Precaudal: 24,3/21,6 Trunk: 8,37/7,44
Based on Amargasaurus (I wanted Dicraeosaurus as another Flagellicaudatan, I do lack good material on it.): Precaudal: 14,85/13,2 Trunk: 6,75/6

The latter seems quite dinky but do not forget that it would have a tail in excess of 20 metres...

I try to make the same calculations based on other sauropods, but it may take some time to get enought material.

Disclaimer: All these estimates are purely speculative and are prone to be erroneous due to the fragmentary nature of A. fragillimus.

Edit:
Another (conservative) estimate for A. fragillimus based on OMNH 1670
Lenght: 40,5/36 meters Weight: 88,6/62,2 metric tons"

Note that this is based on taxa with relatively small centra and big neural arches/spinous processes and also on taxa which show the opposite.

I hope I do not need to regurgitate further stuff from back then, like the variable

And yes, yes he absolutely did. You have to be blind to miss it.

So where is he axactly deriving A. fragillimus lenght from Diplodocus? Nowhere.
He uses Diplodocus "for the sake of illustration". One has to be blind to miss that.




[/quote]

[Dakotaraptor]

Jun 1, 2013 22:26:08 GMT 5 theropod said:

How did you scale them?

The Epanterias is based on coracoid (~33 cm). While this Acrocanthosaurus is based on femoral length (~128 cm). 

[theropod]

stomatopod: by that reasoning he doesn't produce a proper estimate at all, only one for the sake of illustration. The only size figures he gives base on it beign an upscaled Diplodocus.
@metriacanthosaur spinodontosaurus: Thanks, nice scales!

[stomatopod]

Jun 2, 2013 0:22:55 GMT 5 theropod said:

stomatopod: by that reasoning he doesn't produce a proper estimate at all, only one for the sake of illustration. The only size figures he gives base on it beign an upscaled Diplodocus.
@metriacanthosaur spinodontosaurus: Thanks, nice scales!

Well, his methodoly is quite mysterious, but earlier in the paper he shows some ratios, I think he even mentions Camarasaurus.

[theropod]

But he figures it as an upscaled diplodocus, and also estimates the weight based on it. every other scientist has since then interpreted it the same way. I highly doubt he would estimate the size based on some other sauropod, and then show it as an upscaled Diplodocus as well as refer to Diplodocus all the time.

spinodontosaurus: The only other figure that exists of "Epanterias" is axis-height, 25cm. The axis in the two specimen you show is about 19-21cm, being smaller in MOR 693. Something I find very odd is that the scapulocoracoid is unfused in even such a large specimen. and I think based on the great variance of proportions I support A. jimmadseni as a valid species.

[stomatopod]

Jun 2, 2013 0:55:29 GMT 5 theropod said:

But he figures it as an upscaled diplodocus, and also estimates the weight based on it. every other scientist has since then interpreted it the same way. I highly doubt he would estimate the size based on some other sauropod, and then show it as an upscaled Diplodocus as well as refer to Diplodocus all the time.

spinodontosaurus: The only other figure that exists of "Epanterias" is axis-height, 25cm. The axis in the two specimen you show is about 19-21cm, being smaller in MOR 693. Something I find very odd is that the scapulocoracoid is unfused in even such a large specimen. and I think based on the great variance of proportions I support A. jimmadseni as a valid species.

Yes, but which other dinosaur he should have used for getting weight estimates? It is figured for "the sake of illustration" as Diplodocus. Should he have taken Brachiosaurus?
And what do you mean that every other scientist has interpreted it the same way? That Carpenter scaled it with Diplodocus vertebral height? This is based on a missunderstanding by Zach Armstrong (and directly parroted by certain members, who claimed that it stood exactly like that in the paper without even reading it) which even claimed that Zach was palaeontologist, which is he not more than you or me.

[theropod]

Well, the size bases on Diplodocus, that's my point. If the weight does, and the scaled image does, why the hell should the lenght base on some other animal? The guys at SVPOW did too.

I have read Carpenters paper. Of course it is for the sake of illustration, the whole estimate is; it still bases on Diplodocus and not on some other sauropod.

[stomatopod]

Well, the lenght estimate obviously is not based on scaling Diplodocus vertebrae, it is mentioned nowhere in the paper.
He also writes shortly before mentioning the size: "Should A. fragillimus
be viewed as a scaled up version of Diplodocus, Barosaurus, or
Apatosaurus?"

He also never wites that he scaled the given total lenght at all.
This makes me wonder if the number he gives just is a guesstimate based on the various data he has given beforehand.

[theropod]

But he also writes "it is shown as an upscaled Diplodocus" implying the estimate was derived that way too. Surely, Carpenter wouldn't produce such inconsistencies as the ones obviously produced in scaling up Diplodocus in the scale and for the weight but not basing the lenght-estimate on it? I find it more likely he miscited the vertebral height, miscitations are quite common actually.