Is 35 tons a typo? Seems a bit weighty for a 35ft hadrosaur.
I'm not sure if it's a typo, but I suspect it's bunk. Most of the specimen remains unprepared at this time. I'm pretty sure they haven't isolated the femur, so good luck on the mass estimate. It's possible they have a solid mass estimate certainly, but I'm skeptical.
This shows that the mineralized soft tissue of Sue was no aberration either. About the same age.
Was there soft tissue preserved in Sue (Field Museum PR 2081)? I don't recall that. I know there has been some soft tissue on a Museum of the Rockies specimen. I cannot put my hand on my copy of the "Sue" monograph, but I don't remember anything about soft tissue in it. Could be, though (I wasn't ever reading that thing looking specifically for soft tissue stuff).
Either way, it's not an aberration. The MOR
T. rex specimen described in 2005 was from the Hell Creek. Lots of "pieces" of fossilized skin have been found in the Hell Creek and Lance formations and most of the dinosaurs classically regarded as "mummies" come from the Lance/Hell Creek sequences. Preservation of this kind is rare, but not miraculous.
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