Dakota Goes Digital: Replicating a Mummy Arm

Reonstruction by Natee Puttapipat from Drumheller et al., PLoS One, 2022

Confession time: I love giving nicknames to the specimens that I find. It makes them really easy to recall compared to listing off a specimen number. Valerie? Yeah that's a Tyrannosaurus rex. Cap'n Chuck, yeah that's a Platecarpus I found in 2006. So much simpler than remembering RMDRC 22-014 and RMDRC 06-009 respectively. And we're of course not the only ones to follow this practice.

The frill of Princess Lumpybumps, how it got its nickname

Way back in 1999, a teenager named Tyler Lyson found a dinosaur on a ranch owned by his uncle in North Dakota. The specimen was impressive, and was recognized early on to be a "mummy" of a duck-billed dinosaur, Edmontosaurus, that had lots of fossilized skin surrounding its bones. Of course a specimen like this was going to need a nickname so Tyler called it "Dakota". The specimen was excavated by the Marmath Research Foundation in 2004. Fast forward a few more years and Tyler is now Dr. Tyler Lyson, who we work collaboratively with from time to time at the Denver Museum of Nature and Science. Dakota has now made it to the North Dakota Heritage Center and State Museum in Bismarck, reposited with the North Dakota Geological Survey. More information is available on the ND State Museum Blog.

Denver Museum crew excavating a Triceratops that I discovered

In the museum in North Dakota, Dakota the Edmontosaurus has recently gone on display showcasing the original fossils, new artwork by the incredibly talented Natee Puttapipat, and more importantly replicas of many of the skin impressions. Replicating a dinosaur mummy is a tough thing to do, since so much research down to the molecular level is going on with Dakota and nobody wants to risk contaminating it. Traditional silicone molds were determined to be too risky for the safety of the specimen, so everything was scanned at 25 micron level of detail. To put that into perspective, a human hair is usually 50-75 microns in diameter, so this scanning preserves even the finest structures digitally.

Dr. Clint Boyd and crew supervising the move of Dakota, from ND State Museum Blog.

We at Triebold Paleontology Inc. are world leaders in making digital things physical again. Our 3D department was able to print the 3D file full-sized, separated mostly on crack lines going through the real specimen. We then took those parts and assembled them into the full arm. The detail is so precise that you can see the marks where researchers cut away a sample of the skin on the original fossil to analyze. 

Prototype copy being painted with the original arm in the background

Why am I mentioning this now? TPI has recently completed an agreement with the Heritage Center in North Dakota to offer replicas of this amazing fossil arm for the very first time! You may have seen the first (and up to that point only) copy of the replica on display at SVP this past year in Minneapolis. We are now the only authorized company that can make these exquisitely detailed and painted copies for museum exhibits across the world. Contact Jacob Jett for pricing and delivery timelines 

Prototype copy at the NDGS display during SVP 2024

Pete III Final Update: In Its Forever Home

This post has been a long time coming. A little over 13 years from when we first dug a hole in the ground for a toe fragment in Central Montana, our giant Daspletosaurus sp. "Pete III" is now on permanent display at the Cincinnati Museum Center! A photo of Pete's metatarsal was prominently featured in my first blog post here way back in 2010. We put over a decade into excavating, preparing, scanning, molding, casting and assembling this specimen (click these links to go directly to the older content). I'm happy that it's finally done, but I'm kinda sad to see it go all the same.

The original hole in the ground, field season 2005

The first ugly toe. It got better.

You can search all those old posts on the blog for progress, but now I'd like to share with you the finished product! We mounted all of the original bones (minus the skull, those bones are still loose and in the collections in Cincinnati) on an external steel armature with removable brackets so that anything that needs to be taken off of display for research can easily be done. Daspletosaurus is much more rare than "boring old" Tyrannosaurus rex so the research value of this specimen should be high.

Copies of this ungual can be purchased at www.deeptimefossils.com

The mount itself is a fairly conservative pose, not really running, not really mouth-wide-open. Viewed from near the Allosaurus, it seems to tower over the city skyline (hold the Chili). The restored art deco hall that Pete III now calls home is an exhibit itself and was very well done.

I really like this shot

We tried to make the supporting steel as visually unobtrusive as possible while still being substantial enough to do its job of holding up hundreds of pounds of real bone (and quite a bit of super glue). There might just be as much steel by weight as original bone in this mount, but it really doesn't feel like it.

Every bone gets its own personal mounting steel support

We're really happy how this mount turned out and now all you tyrannosaur researchers out there know who to talk to about planning a visit and publishing. No more excuse to pretend it doesn't exist anymore! And if you notice, things look "unfinished" in the photographs. This is because I helped install it back in August, so if you have better pictures of the display from your next visit I'd love to see them! Here's to thousands and thousands of visitors liking this specimen just as much as we do!

The finished mount, curator for scale

An even better photo without the curator

Pete's huge (as far as tyrannosaurs go) arm

Digging a tyrannobutt

We're back from Montana waiting for the temperatures and fire danger to die down for a bit. Earlier this month though we were battling the gnats working on excavating a dinosaur I found late last summer.

Can you spot the site?

The site is pretty typical for how I find them: about halfway up a 30 foot cliff with a menacing hoodoo overhanging the specimen. I found this site about 2 days before we broke camp last year so I was only able to do the smallest of evaluation digs on it.

Bones on either side of an erosional notch: usually a good sign

 Using air tools I was able to notch out a few of the bones. These were clearly large theropod bones, one looked like a caudal vertebra and I couldn't tell what the one shooting straight into the cliff was. Big theropod in the Judith River formation means one thing: Tyrannosaur! I knew I'd be coming back for this site in 2017.

Duckbills. It had to be duckbills

Additionally at this site was a big wad of predepositionally broken ornithischian (most likely duckbill) bones under the tyrannosaur material. This gave the impression of a stream or oxbow lake bottom assemblage, but sometimes you find good skeletons mixed in with all this material. Unfortunately with fall closing in, I had to abandon the site till 2017.

Storms are no fun in vehicles that lack roofs and windshields

This year however we came out with our big jackhammer and managed to notch out a decent sized evaluation pit. I wanted to get a better feeling for what was present before I suggested getting a bulldozer out there to knock down the whole cliff.

The isolated tyrannobutt

Turns out, it appears it was just an isolated tyrannosaur sacrum with one dorsal vertebra still attached. Not pretty now, but once I prepare it we will see better the shape of the specimen. I'm thinking Albertosaurus, but it's hard to say from this element.

Closeup of the spines. Bonus duckbill chevron at top left

It's a bit of a bummer that there wasn't more of this skeleton. It was going in towards the head but it was just not meant to be. I'm happy to find this now before we invested time and resources removing 15 feet of really tough sandstone from the area though. Guess I'll just have to spend the rest of my summer looking for more dinosaurs. It's a tough job but somebody's got to do it!

We're still out doing fieldwork

The glamour of digging holes in the ground while battling flies and heatstroke. Come for the stuck side by side, stay for me breaking a 2x4 with my brute strength! Enjoy!

It's field season again

Wandering around Montana means lack of blog updates, but we're at least finding a few new dinosaurs. Here's a few good pictures from our first trip out to the badlands. Back out soon to work a few hadrosaur and ceratopsian sites in the blistering heat.

Big mother wolf spider with the kiddos

Dinosaurs hide everywhere

Jacob and I load a huge (4 foot plus) duckbill tibia into the truck

Sometimes the dinosaurs hide really well

Curatorial boot for scale, another duckbill site

Sometimes geology needs to be shown who's boss with power tools.

Pete III finished. For now.

Just for the weekend, the prototype cast of our Daspletosaurus Pete III (RMDRC 06-005) will be shown off in the atrium of the museum, before it gets decent photographs and heads to its forever home. Yes, it has a 2006 specimen number.

The original site as found/explored in July 2005. We were so young.

We've been working on this for a decade. I'm not sure if I should take the day off to celebrate, or take advantage of the free time of getting a huge project off my plate and start something new and exciting. In the meantime, enjoy some of the snowy photos, better well-lit ones to come in a week.

So, this is what a pile of Daspletosaurus looks like

It just looks like such a fast critter, not like dumpy Tyrannosaurus

Nearly 11m of birdy goodness

Daspletosaurus Assembly: Building a Frightful Lizard

There is actually a very good reason why I haven't updated this blog in a while: We've been up to our armpits in the lab building the prototype cast copy of Pete III, our 11m Daspletosaurus.

Ilium cast fresh in the mold

Progress is going quick by Academic standards, and we hope to finish the cast by early May.

Both feet before assembly

Jacob and I called "dibs" on making this skeleton, since we've been working on the project for 10 years.

We just admired this for a few days

It really is a great thing to see all this hard work finally amount to something tangible

Making the pubis. It is no longer blue

Plus everyone loves a huge tyrannosaur, especially one way more rare than T. rex.

Progress as of a few days ago. Tail is 17 feet (5.2m) long

Stay tuned for some more exciting progress really soon. We're finishing the neck, working out the gastral basket and have a few cervical ribs to go. 

A day in the life of a Daspletosaurus bone

Some people asked me not too long ago about what we do in order to get some of these bones ready for molding. In the case of Pete III, our Daspletosaurus from Montana, the condition of the bone gave us some additional problems. All specimens of course get excavated and painstakingly prepared by our expert staff, but in Pete III's case, even the prep necessitated the invention of new techniques which I published on a few years back. The entire specimen was pixelated, with some bones made up of hundreds of thousands of fragments. Lots of glue was needed to even expose the bone, which is huge, literally Tyrannosaurus rex sized. Once done the left ilium looked kind of like this:

Next up is reconstruction of any major missing bits and holes with epoxy putty like Aves Apoxie Sculpt. That's the grey stuff.

We then apply a barrier layer of B-72 to hold everything together for the next steps. Shiny!

Then we take our gorgeous bone and smear the whole thing with tinted Hydrocal.

 Yuck. OK now it doesn't even look like a fossil. Never fear, most of it will be gone soon. The main aim is to work the Hydrocal into all the seriously tiny cracks in the surface to better hold the bone together. This also reduces the amount of the relief in the specimen so molding goes much faster. The excess on the surface is removed with air abrasion.

Doesn't look so shiny anymore, but we can fix that with a wee bit more of very thin B-72.

And there you have it, one half of a bone restored in a few days time. Now we just make a support jacket so the entire thing can be flipped over and the process repeated.

Please welcome the new "Avaceratops"

It's a happy day when we get to unleash a brand new dinosaur on the world. After 3 years of hard work and a lot of sweat, we get to show off our new primitive centrosaurine ceratopsian!

The newest skeletal, copyright Scott Hartman, used with permission

The skelton in all it's glory, Curator for scale

The bones of the specimen that were recovered, copyright Scott Hartman, used with permission

We discovered the specimen at the end of August 2012 on private land in central Montana. The specimen was found near the top of the Judith River Formation, in rocks approximately 75 million years old. You may notice we are using the name "Avaceratops" in quotes here. We're not trying to be coy or mysterious, but with the stratigraphic difference (our specimen is about 3 million years younger than the holotype) and the differences in skull morphology highlighted below, we have come to the conclusion that this is a different animal than true Avaceratops lammersi.

Someone put a lot of work into this. Tell me who you are so I can give credit!

The skull is quite different in detail. It totally lacks a nose horn, and the long brow horns (until recently a rarity in centrosaurine ceratopsians) point forward and even slightly back towards each other, much different than the other two known skulls. It's large "forehead" area is more reminiscent of the recently described Nasutoceratops, from about the same time in Utah.

Overall, the skeleton is 3.5m long and about 1.2m tall. We estimate the critter was about 3 to 4 years old when it died, both based on its relatively small size and the extensive lack of fusion in its skeletal elements. It's pelvis was reassembled from over 30 separate elements. What a job.

Digging down into the quarry site

After the dinosaur died, it's partially mummified body washed down a stream channel until it hit a logjam composed of not only actual logs, but the limb bones of a large hadrosaur. Here it lodged upside down and then began to partially disarticulate. Some of the dried skin over the hips was surprisingly well preserved though, as addressed in an earlier blog post. A few tyrannosaur teeth were found at the site, but we feel those were incidental background fossils, as no predation or scavenging marks were observed on the bones.

Tyrannosaur tooth found at the site

After all this painstaking work in sometimes miserable conditions, we are excited to share the product of this discovery with the rest of the world. After getting unveiled to the press on Wednesday, September 16 at 10:00am the mounted skeleton will be on display at the RMDRC for just a few weeks before making its first trip to Dallas, TX for the 75th meeting of the Society of Vertebrate Paleontology. You must come see it!

The mount showing the horn shapes (and absences)

Rear view of skeleton