Showing posts with label Thescelosaurus. Show all posts
Showing posts with label Thescelosaurus. Show all posts

Wednesday, January 24, 2018

The little Thescelosaurus that could

The Hell Creek Formation is so much more than just Triceratops and Edmontosaurus and Tyrannosaurus rex. There, I said it. I head out there to swelter and dig nearly every summer, and it's truly not the big famous dinosaurs I'm interested in. This is where Jonathan comes in. This specimen, RMDRC 06-007, was collected over a decade ago and sat in our collections partially prepared for most of that time. Coincidentally it's a specimen of Thescelosaurus neglectus, the "neglected marvelous lizard" and the name sure fits. 
Partly prepared in the jacket, tail and right leg in other places

In the spring of 2017 we decided we needed to do something with the specimen. Jonathan was mostly articulated in a large heavy field jacket. The first step was to get all the parts into a state where we could mold them, so lots of careful preparation, and lots of consolidant was required. Jonathan was a large (by Thescelosaurus standards) and old animal, but the bones were still preserved with the insides like coffee grounds, ready to pour out in a pile of disappointment if the bones were even looked at the wrong way.
Right foot after prep and restoration

Any damage was stabilized and repaired as we worked. Missing parts were scanned with an Artec Spider structured light unit and we printed them out using our Form2 SLA printer and the usual PLA filament scribblebots. Molding was quick and straightforward for the most part, though the chest cavity posed a special problem for us. The chest cavity preserved a series of calcified intercostal plates between the ribs, which only start to solidify when the animal hits a ripe old age. These super delicate features prevented us from molding a set of ribs that could be immediately used on the cast, so instead we molded them all as a whole unit, cast them, then modified the casts to fit on the mount, then remolded them. Straightforward, right?
Posterior dorsal vertebrae

Assembly was pretty easy as well, though at nearly 14 feet long we were always remarking on how surprisingly big this animal was. It's huge clod-stomper feet came out very well, and since we had calcified cartilage with the specimen, we thought it would be dumb not to include it on the finished mount. In the end we came up with what I think is the very best and most scientifically accurate reconstruction of this poor neglected animal ever attempted. I hope you all like it as much as I do.
Finished mount, Grace for scale

An unusual view highlighting the cartilage

He just looks so dang HAPPY!

Friday, December 9, 2011

Show Thescelosaurus some love

When is a dinosaur not a dinosaur? When it's fairly dull I guess. Just look at Thescelosaurus. Not brainy, not much in the way of fangs, claws, armor, clubs, or anything else sexy. It's also a fairly rare dinosaur, with just a handful of reasonably complete specimens. We at the RMDRC have been lucky, preparing the only complete skull so far (on "Bert"), as well as now preparing a pretty dang complete skeleton, "Jonathan".

Right leg from the former display
Jonathan was discovered in 2006 in the Hell Creek Formation of Montana. It was nearly complete, minus the tip of the tail and the head/neck where it had eroded out into the gully. Lying belly-up, once show prepped, it nearly looked like it died just yesterday.


Main jacket

Look at that cute little first chevron
We have now started to prepare all of the bones free of the matrix. We will restore them, mold them, reconstruct the missing bits, and offer a cast of this big Thescelosaurus (13-14 feet or 4m long) for sale to institutions. The original will be mounted in 3d on a steel armature. That last bit is a LOT of work, but it's also pretty satisfying and a bit of fun too, especially if you enjoy doing metal work!