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Tyrannosaurus rex
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Tyrannosaurus rex specimen MOR980
*This image is copyright of its original author A well preserved specimen roughly in the same size range as Scotty and Sue according to the museum of chicagos lead dinosaur curator.
Tyrannosaurus rex RSM P2523.8 (Scotty)
 *This image is copyright of its original author Currently the largest Tyrannosaurus specimen known to science supplanting Sue in 2019 Tyrannosaurus Sue (by Franoys) with Scotty (by Randomdinos)  *This image is copyright of its original author
@JurassicDD
I disagree that MOR 980 is comparable in size to Sue and Scotty. As per the Theropod Database (link), its femur is 123.2 cm, its dentary is 90 cm, and its maxilla is 77 cm, compared to 132.5 cm, 101 cm, and 86.1 cm in Sue, respectively. Averaging the disparity of these 3 elements and scaling down from Sue gives about 6.28 tonnes, so I don't know where the museum director got that it was comparable to Sue from.
Fran has stated MOR 980 has not yet had a detailed description it has never been described in detail and that is the best way to know a specimens true size. Scotty was once seen as a smaller specimen than Sue then it was finally described properly and look how that turned out all of its weight bearing elements are larger than Sues are and has been estimated to out mass Sue and we know this because of the detailed description. So until the specimen gets a proper detailed study that flat out states it is not in the same range as Scotty or Sue i will go with what the museum director has to say because he most likely does not have a massive bias against the animal. The theropod database has a ton of outdated stuff on there so i would not take what it has to say as gospel.
If it doesn't have a detailed description, it's certainly possible it could end up comparable in mass to Sue or Scotty. But if I were you, I would take museum figures of mounted skeletons (not just Tyrannosaurus but of most dinosaurs) with a grain of salt as they are often either taken along the curves or improperly measured.
Examples: -FMNH states Sue to be 12.8 meters and their Patagotitan to be 37 meters; they are actually 12.3 meters and 31 meters as per Scott Hartman's and Greg Paul's reconstructions of them. -BHI states Stan to be 12.2 meters; it is actually either 11.78 meters (as per the mount scans of Bates et al. 2009 and Hutchinson et al. 2011) or 11.28 meters (Scott Hartman). So I'm not saying it's not similarly sized to Sue and Scotty as it very well could be, but don't take mounts at face value. (06-10-2020, 12:35 AM)DinoFan83 Wrote: If it doesn't have a detailed description, it's certainly possible it could end up comparable in mass to Sue or Scotty. But if I were you, I would take museum figures of mounted skeletons (not just Tyrannosaurus but of most dinosaurs) with a grain of salt as they are often either taken along the curves or improperly measured. Im very aware of the issues that some museums have and the issues with tons and tons of skeletal mounts but the best way to know are from detailed studies from actual experts who know more about these animals and there body structure then me and you ever will and sadly we do not have that yet for MOR 980 or a fair few other Tyrannosaurus specimens. The theropod database is full of outdated information i might add. So i wont take mounts at face value ( i rarely do anyway) and you should not take what the theropod database as complete gospel. Im going through the database now and it does not even look like it has any of the updated measurements for Scotty unless im just blind. 
Explain to me why so often there is a lack of consensus regarding the measurement of dinosaur bones. Giganotosaurus is one case, and looks like that website has 1.29 m for Scotty's femur length (Persons et al. 2019 reports 1.333 m). In mammal bones, the difference is a few millimeters at best. Perhaps the larger the bone, the more difference in measurement between two observers? For instance, measuring a hemimandible of a cat, the measurement is shorter if the hemimandible is rested on its lateral or buccal side, and longest if measured in its natural in situ position (resting at the inferior base).
(06-10-2020, 01:12 AM)tigerluver Wrote: Explain to me why so often there is a lack of consensus regarding the measurement of dinosaur bones. Giganotosaurus is one case, and looks like that website has 1.29 m for Scotty's femur length (Persons et al. 2019 reports 1.333 m). In mammal bones, the difference is a few millimeters at best. Perhaps the larger the bone, the more difference in measurement between two observers? For instance, measuring a hemimandible of a cat, the measurement is shorter if the hemimandible is rested on its lateral or buccal side, and longest if measured in its natural in situ position (resting at the inferior base). A lot of it comes down to just bad descriptions and hearsay really. It took years and years to actually properly dig up Scotty because of its size and the specimens bones were deeply packed in thick iron-laden sandstone which took more than twenty years for the team to fully remove then excavate and assemble the majority of the skeleton properly then it was finally studied and its bones were measured this is much better than instead of people just going from pictures of the mounts and stuff like that. So much when it comes to dinosaurs on the internet is really outdated and often it never gets updated then people carry on using it as a source and the cycle continues just checking the theropod database shows this. Does not help either that good detailed descriptions take so long to be done then to go through the review process. Might take another 20 years until we get another good description for a big theropod dinosaur. (06-10-2020, 12:44 AM)JurassicDD Wrote:(06-10-2020, 12:35 AM)DinoFan83 Wrote: If it doesn't have a detailed description, it's certainly possible it could end up comparable in mass to Sue or Scotty. But if I were you, I would take museum figures of mounted skeletons (not just Tyrannosaurus but of most dinosaurs) with a grain of salt as they are often either taken along the curves or improperly measured. I think it's more likely that just Scotty doesn't have its measurements properly updated. Looking at, for example, the rest of the Tyrannosaurus measurements, they seem to be coherent with the rest of the literature (e.g the femur lengths of MOR 980, MOR 555, and BHI 3033 as well as other specimens are consistent with the provided measurement from Larson et al. 2008 (Tyrannosaurus Rex the Tyrant King)). The femur measurement for Scotty is not that far off either from what it actually is. So while a few things may need to be updated and I won't take it as gospel, I believe the Theropod Database should still be a fairly reliable source. I could even email Mortimer and ask them about this, if needed. EDIT: Looks like Scott Hartman's skeletal for MOR 980 seems to be about 11.7 meters long (link), and Scott likely had access to data, measurements, and whatnot that most other people didn't have when he made it; if he didn't, it would've basically been impossible to make it in the first place. Based on the image you posted, it looks fairly similar in build to AMNH 5027 (who is 11.8 meters long and 6.6 to 6.9 tonnes based on Seebacher et al. 2001 and SIW's GDI of it), and scaling from the AMNH specimen gives ~6.4-6.7 tonnes. @tigerluver It's possible these differing measurements are due to differing metrics for measuring. I know some people prefer to measure femurs along their curvature and some like to exclude the femoral head instead of straight line measurements, so maybe varying measurements of femora are due to this. (06-10-2020, 02:46 AM)DinoFan83 Wrote:(06-10-2020, 12:44 AM)JurassicDD Wrote:(06-10-2020, 12:35 AM)DinoFan83 Wrote: If it doesn't have a detailed description, it's certainly possible it could end up comparable in mass to Sue or Scotty. But if I were you, I would take museum figures of mounted skeletons (not just Tyrannosaurus but of most dinosaurs) with a grain of salt as they are often either taken along the curves or improperly measured. All that link did was send me to Scotts older Sue ? and once again i will wait for a detailed description for the specimen if we ever get one that is.
It's linked to a comment. If the link did not work, this was what the comment said. It was from Spinodontosaur4, July 25, 2013:
"I was just doing some poking around in regards to "giant" 'rex specimens, and came across your old skeletal of MOR 980 from 2004. Now from my understanding, many of it's preserved elements are if anything smaller than in Stan, never mind Sue. Yet your old skeletal is pretty darn big; circa 11.7 meters based on the low-res version I'm looking at, much bigger than Stan." (06-10-2020, 04:52 AM)DinoFan83 Wrote: It's linked to a comment. If the link did not work, this was what the comment said. It was from Spinodontosaur4, July 25, 2013: Well thank you for looking for that but is a diagram from 2004 so that is pretty old and while Hartman likely did have access to information we dont have things could have changed since then and i cant even see the skeletal so it really does not do much and Hartman has been inaccurate before the comment is even stating that its loads bigger than Stan is yet Stan has been measured to be around 11.7 m with current studies unless its going on about how Scott got Stans length wrong and had it in the 10 m range. Im not saying you are wrong you could be bang on regarding the specimen but once again we have no detailed description on the specimen from an expert and that is the best way to go. You can stick to what you want to (and we both know you will) but i will wait for a detailed description from some experts or if Fran or anyone on the discord knows anything regarding the specimen. I trust them more than i trust you for reasons we have gone over time and time again in the past.
I suppose we can each stick to what we'd trust. I think that this (link) is the diagram; for what it is worth, as far as I can tell, since 2004 onwards, the main updates to Scott's Tyrannosaurus skeletals appear to be related to soft tissue, articulation, and posture while the TL of the specimens does not appear to have changed. But yeah, it's possible that post 2004 information will get something new.
As for BHI 3033, I think that both Scott Hartman's version and the 11.78 meters of the mount are plausible. This is something Franoys had to say about it: "I know about his concerns; first I'm not sure there really is spacing between the skull and the cervical vertebrae, I did the restoration of all of the cervicals and attached the skull normally, what is true is that the neural spines of the neck are angled backwards, and they make it look as if there was a spacing, specially in the scan in Hutchinson et al 2011; but this is not the case when you look at how the skull is articulated in higher res photographs or scans. About the tail; it does seem like the specimen preserves a few distal caudal vertebrae, according to the BHI site, caudals 35 and 39-41 are preserved, and when scaling Sue's posterior region of the tail to them it ended up just like this, in fact that makes me wonder if the posterior most caudals in Sue's mounted skeleton aren't too small, and if the tail shouldn't be a bit longer, as Sue only preserves caudals up to caudal 35 going by Brochu's 2003 osteology. There is no reason to be very concerned about the length however, there is enough margin of error for both reconstructions to be plausible. And after all, Tyrannosaurus tail is still not fully known." |
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