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Post by dinosauria101 on Aug 4, 2019 16:17:55 GMT 5
 Archaeotherium vs Utahraptor (max entelodont, average dromaeosaur) |
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Post by theropod on Aug 4, 2019 17:21:04 GMT 5
sam1 You think so? As far as individual variation between theropod specimens goes, these are actually quite similar, especially if you consider the skeletals were done by different people, but also in terms of their measurements and proportions. Individuals of T. rex have a far far wider scope of variation than between these two. Look how much other T. rex specimens differ, even in restorations done by the same person: img00.deviantart.net/124d/i/2015/106/b/4/don_t_mess_with_t__rexes_by_scotthartman-d7t58oi.jpg
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Post by dinosauria101 on Aug 4, 2019 18:22:15 GMT 5
Max size Rhamphosuchus vs Tyrannotitan  |
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Post by theropod on Aug 4, 2019 18:46:26 GMT 5
Can I get proper, detailed verification for this? I just checked Wikipedia's article; 6-12t is from a 1985 paper. While I'm not one to outright dismiss a source based on its age, more so if it's not ridiculously old, I'm sure we today can do better with estimating size.Maybe scaling up from other ceratopsians would be the way to go? We could scale up Titanoceratops (though that may be a bit of an underestimate, since the frill and skeleton are both less solid than in Triceratops) This would only shift the problem onto another taxon and introduce additional error factors. The question is, are there any more accurate size figures for Titanoceratops? There is easily sufficient material to make a reliable size estimate for Triceratops, the question is just whether someone has actually done it. Seebacher (2001) estimated an 8m Triceratops horridus at roughly 5t, which seems unreasonably low, but is at least based on some sort of volumetric methodology. Greg Paul (2010, 2016) estimates an 8m Triceratops horridus at 9t in the Princeton Field Guide, which is also presumably based on volumetric models. The largest specimen Greg Paul lists on his website (USNM 4276) he estimates at 9.3t, with a ~1.3m femur. Based on his skeletal (2016), that would correspond to a total length (axial length from the tip of the tail to the tip of the rostral) of about 8.6m and a shoulder height and skull length of about 2.7m. So this is consistent with the skull length and overall size suggested by the largest fragmentary material, as well as the skull length of Eotriceratops¹. I’ve tried roughly replicating this in Blender based on his multiview skeletal scaled to the appropriate dimensions, here are the results:   | Specimen/dimensions | USNM 4276, 1.3m femur (Paul 2010), ~2.7m skull, ~8.6m TL
| UCMP 12861, Scott Hartman’s skeletal scaled to 2.7m long skull as per Eofauna, ~9.2m TL, dorsal view adapted from Paul (2016) | Axial Postcranium
| 7.1566m³ | 8.3114m³ | Head
| 1.5637m³
| 1.5637m³ | Forelimb [×2]
| 0.1564m³ [0.3128m³] | 0.2690m³ [0.5379m³]
| Hindlimb [×2]
| 0.2508m³ [0.5018m³]
| 0.3477m³ [0.6955m³]
| Total [mass]
| 9.5349m³ [9535kg]
| 10.7607m³ [10761kg]
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So assuming a density of 1.0, we get a total body mass of about 9.5t. I’d take this with a grain of salt, especially around the head, which is tricky to model, but this should be good enough as a test of Paul’s estimate.
EDIT:I’ve added an estimate based on scaling Hartman’s skeletal to a skull length of 2.7m and adapting the lateral-view silhouette of the model accordingly.
As of my knowledge, this specimen would correspond to the largest recorded size for this taxon, or any ceratopsian for that matter. If you have evidence of larger specimens, pleast post it, otherwise, I would suggest that 12t is an overestimate. Paul, G.S. 2010. The Princeton field guide to dinosaurs. Princeton University Press, Princeton.
Paul, G.S. 2016. The Princeton field guide to dinosaurs. 2nd Ed.. Princeton University Press, Princeton.
Seebacher, F. 2001. A new method to calculate allometric length-mass relationships of dinosaurs. Journal of Vertebrate Paleontology 21 (1): 51–60.
¹https://www.deviantart.com/eofauna/art/Eotriceratops-vs-Triceratops-341153326
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Post by Verdugo on Aug 4, 2019 19:27:36 GMT 5
^ Is the specimen you're talking about here similar in size to the 'largest specimen' by Scott Hartman (which is also 2.7m in height when i scaled it using the scale bar)? I'm wondering if a 3m tall Triceratops is ever in existence. |
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Post by dinosauria101 on Aug 4, 2019 19:28:18 GMT 5
Isn't BYU 12183 larger than that?
(Maybe I should have clarified earlier on), but there was a discussion about this on one of Carnivora's Triceratops threads (American mastodon vs Triceratops), which resolved this issue. Concerning BYU 12183, I think a screenshot from Spinodontosaurus resolved it.
(You'll have to check yourself however, because my IP seems to be blocked).
If that's untrue, I'm open to a new range of Triceratops size estimates, but this exact discussion was on Carnivora and I see no reason why it would not apply here.
EDIT: Yes Verdugo, there was also 3 meter Trike mentioned in the thread. Thank you for mentioning it
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Post by theropod on Aug 4, 2019 19:37:20 GMT 5
Verdugo That one is 2.6-2.7m tall depending on how exactly we measure the scalebar, but it seems to be shorter and smaller-skulled than Paul’s reconstruction (7.3-7.6m long and with a ~2.2m skull). As for a 3m tall trike, that depends. Hartman claims this is the largest specimen, so since the largest Trike skulls are fairly fragmentary, perhaps he restores it smaller than Paul. On the other hand there was a paper that mentioned a 2.5m trike skull as having been measured, so it must have been substantially complete. In that case, perhaps such specimens could have gotten 3m tall following Hartman’s reconstruction.
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Post by theropod on Aug 4, 2019 19:41:47 GMT 5
Isn't BYU 12183 larger than that? (Maybe I should have clarified earlier on), but there was a discussion about this on one of Carnivora's Triceratops threads (American mastodon vs Triceratops), which resolved this issue. Concerning BYU 12183, I think a screenshot from Spinodontosaurus resolved it. (You'll have to check yourself however, because my IP seems to be blocked). If that's untrue, I'm open to a new range of Triceratops size estimates, but this exact discussion was on Carnivora and I see no reason why it would not apply here. EDIT: Yes Verdugo, there was also 3 meter Trike mentioned in the thread. Thank you for mentioning it New or old carnivora? If you really need to cite carnivora instead of the sources for the information presented there, can you be precise about that please? |
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Post by dinosauria101 on Aug 4, 2019 19:51:05 GMT 5
Isn't BYU 12183 larger than that? (Maybe I should have clarified earlier on), but there was a discussion about this on one of Carnivora's Triceratops threads (American mastodon vs Triceratops), which resolved this issue. Concerning BYU 12183, I think a screenshot from Spinodontosaurus resolved it. (You'll have to check yourself however, because my IP seems to be blocked). If that's untrue, I'm open to a new range of Triceratops size estimates, but this exact discussion was on Carnivora and I see no reason why it would not apply here. EDIT: Yes Verdugo, there was also 3 meter Trike mentioned in the thread. Thank you for mentioning it New or old carnivora? If you really need to cite carnivora instead of the sources for the information presented there, can you be precise about that please? Oh, sorry. Current Carnivora. (the only reason I am citing it is because there was this exact same discussion and I just think it could help out here) |
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Post by theropod on Aug 4, 2019 20:01:20 GMT 5
I couldn’t find any such discussion on that thread, just a bunch of people posting random size comparisons from the internet. Only this comparison, posted by a guy called carnivorous vulgaris without attribution to the original author, which looks like part of it might have been made by Spinodontosaurus.  Is that what you mean? This says 11t, not 12, and it doesn’t give any methodology. I already wrote that the 2.7m skull from the eofauna restoration would be consistent with Greg Paul’s reconstruction scaled to the 1.3m femur from his website. And for FSMs sake, get yourself a HTTP proxy or something and use it to at least find the link to the specific posts you want to cite. It’s pretty annoying you know, having to search through whole threads and having wonder whose post and what exactly you are referring to. |
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Post by Verdugo on Aug 4, 2019 20:10:41 GMT 5
Verdugo That one is 2.6-2.7m tall depending on how exactly we measure the scalebar, but it seems to be shorter and smaller-skulled than Paul’s reconstruction (7.3-7.6m long and with a ~2.2m skull). As for a 3m tall trike, that depends. Hartman claims this is the largest specimen, so since the largest Trike skulls are fairly fragmentary, perhaps he restores it smaller than Paul. On the other hand there was a paper that mentioned a 2.5m trike skull as having been measured, so it must have been substantially complete. In that case, perhaps such specimens could have gotten 3m tall following Hartman’s reconstruction. I thought Hartman stated that the skull of his specimen was 2.5m long (see his comment)? Perhaps he got it wrong or he measured the skull differently? |
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Post by theropod on Aug 4, 2019 20:15:42 GMT 5
What comment do you mean?
If he stated that, he’s certainly correct. The resolution in the online version is pretty poor, which makes measuring pretty difficult.
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Post by Verdugo on Aug 4, 2019 20:54:23 GMT 5
What comment do you mean? If he stated that, he’s certainly correct. The resolution in the online version is pretty poor, which makes measuring pretty difficult. The third comments from top-down in the link i posted in my previous comment (page 5 in his DeviantArt comment page) Could you try putting the 1.3m femur into Hartman's to see how big it can get? Just curious |
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Post by dinosauria101 on Aug 4, 2019 20:58:34 GMT 5
theropod
I believe the discussion was on the first page (look for a poster called Gaurus, quote blocks from ChocolateCake123, a screenshot of Spinodontosaurus from the old site, and a wall of crossed out text. Again my apologies, but as soon as the issue I mentioned in the other thread is solved, I can link threads consistently).
About the size scale, that was a bit beyond the scope of what I meant. But you may have a point. I think I'm open to a max of anywhere from 9-12 tons.
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Post by theropod on Aug 4, 2019 21:26:51 GMT 5
Verdugo Well, your measurement of how long the femur in Hartman’s skeletal is is as good as mine, but we inevitably run into the same problems due to the low resulution of the image. The femur in the skeletal reconstruction is 59px, and the larger silhouette is about 29% bigger than that, so that pretty much gives us our 1.3m femur. The third comment from the top down in the link you posted is a one-liner not even posted by Hartman himself, searching for "2.5" also doesn’t return any result on that page. With the new deviantart layout there are no page numbers for comments anymore. But I’m happy to take your word for it if you are sure he wrote the skull is supposed to be 2.5m long. dinosauria101 None of the posts by Gaurus provide any evidence for the weight of the largest Triceratops specimen whatsoever, in fact all he does seems to be to call the 12t figure into question, not support it. The post with the strikethrough-text is Ausar’s, so I assume you meant that one? There’s a screenshot in there of a topix post from 2014 made by spinodontosaurus, where he states that UCMP 12861 could have reached 10-11t. But firstly, I don’t see how this is very meaningful seeing how he doesn’t give any information on where that figure comes from, and secondly that’s actually closer to the 9.5t estimate I just made, or the one by Greg Paul, than it is to the 12t you always cite. The specimen referred to is the same I already mentioned in my post, with the skull Eofauna estimates at 2.7m. The same size the skull turns out for Greg Paul’s skeletal scaled to the maximum femur length, a specimen he estimated at 9.3t. We can try to see how big Hartman’s skeletal turns out with that skull size though. EDIT: 10.7t, see the post→ with the weight estimate for details.So, where exactly is your source for 12t, again?
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