Tyrannosaurus rex

[DinoFan83]

I'd like to make a post on the Tyrannosaurus models from Hutchinson et al. (2011), and a correction of their model for Sue.

As many of you already know, even their minimal model (9500 kg) is substantially larger than other estimates for Sue (such as 8400 kg via Scott Hartman or 8200 kg via Asier Larramendi). However, there are also a lot of issues plaguing this reconstruction. They are as follows:

-Their model for Sue has no spinal curvature and therefore the torso is longer and more voluminous than it would have been in life. This is in contrast to, say, Scott Hartman's Sue, which has about 10% more spinal curvature than that.
-Their model for Sue has the ribcage too wide; as they acknowledge themselves, "the torso of the mount is inflated in width due to a dorsal displacement of the transverse processes on the trunk vertebrae, which forced a dorsal displacement of the tubercular articulations and a lateral expansion of the rib cage as a whole."
By my measurement it's about 1.8 meters as opposed to 1.6 meters in Scott Hartman's model (given a 132.5 cm femur), so it's about 13% too wide.
-The dorsal ribs on the mount, instead of being angled backwards following Hartman, Larramendi, and Greg Paul's comment on the study, are strongly swept anteriorly, inflating the torso's volume. They're about 25% more anterior than the ribs in Hartman's, meaning the torso is 12.5% too voluminous with the rib articulation.
-Following Scott Hartman's standards for soft tissue, the torso and the neck seem (to me at least) to have about 10% too much of it.

The correction:
Sue's torso mass is listed as 5,560 kilograms for the minimal model. Applying each correction will result in a decrease in its overall volume as will be discussed below.

10% more spinal curvature: Volume reduction of 10%, meaning the mass is decreased to 5004 kilograms.
Deflating the ribcage 13%: Volume reduction of 13%, meaning the mass is reduced to 4428 kilograms.
Sweeping back the ribs 25%: Volume reduction of 12.5%, meaning the mass is reduced to 3936 kilograms.
10% less soft tissue on the torso and neck: The neck model is listed as 504 kilograms, and with the torso at 3936 kilograms, this reduces their volumes to 458 and 3578 kilograms, respectively. 

Overall, correcting all of this, the minimal model is reduced by 2028 kilograms. Thus, with all these issues fixed, the minimal model for Sue of Hutchinson et al. ends up at 7470 kg. Going by this, I would say that 7470-8400 kg is a good size range for Sue when considering both this and Hartman's model, with a mean of about 7900 kg.
Given that the mean estimation matches Asier Larramendi's Sue, and that Hartman's Sue as well as the corrected model both differ from the mean by about the same percentage (thus representing a plausible size pattern of seasonal variation), I'd say my correction is highly likely to be correct.
Bear in mind that Scotty would have been about the same size as this model, most likely.

EDIT: this does not use the new density of 0.95 for large theropods from Larramendi & Paul (2020). Applying it to these estimates changes the size range from 7770-8700 kg, with a mean of about 8200 kg. Reply