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

First Kansas Trip in the Bag - 2017

For the first time in a few years, we've been able to hit the Niobrara outcrops in the spring! Holy crap was it cold. The last day out, I don't think it got above 50 degrees, not that the 40mph winds would make it feel any warmer. Perfectly miserable. And just like clockwork, on our last day, as the sun was setting behind a large row of thunderstorms on the horizon, we found the best skeleton of the trip! The rest of the time was staring at blank ground finding fossil poop.

Look at this swirly poop!

I entertained myself by finding a "nice" Xiphactinus tail. I was instructing a new hire on how to actually find fossils in pretty bleak badlands when I saw just a small fragment of tail fin coming out of the rock. I'm happy I found this one as since we have SO MANY Xiphactinus specimens in storage, we've implemented a "one in, one out" policy on these fish and I've somewhat jokingly insinuated firing anyone that finds another of these darn fish. Our newbies were safe.

Well, there's a fish tail

Jesse using a chainsaw to trench around the fossil

When you find weathered out fish tail chunks, you have to chase them in (even if they're "just" a Xiphactinus). Sometimes the rest of the tail is there. Sometimes there's the rest of a 15 foot long fish attached to it. Sometimes it just ends. In this case, we found a perfect lower lobe of the fin, but no body. As far as we were from the truck, I'm happy we didn't have to make a huge jacket, since those are heavy and I'm getting lazy in my old age.

Trenching complete, curatorial boot for scale

Jacketing complete and ready to flip, other curatorial boot for scale

Popping it out and prepping it was also quick. Measuring the vertebrae we found it's the exact same size to complete another Xiphactinus specimen we excavated 3 years ago (which just happened to be missing the tail). This will help us out tremendously when we panel mount the animal in the near future.

Not too shabby!

Other stuff was less plentiful on this first trip, but we were lucky enough to find parts of 3 sea turtles, which is always really nice.

Jesse and grace entrusted with power tools to get to a turtle

And of course at the very last minute, Jesse stumbled on a pretty complete Clidastes skull in an outcrop near where we discovered our gigantic 17 foot Xiphactinus specimen 20 years ago. We worked very hard to excavate the specimen with daylight fading and weather bearing down on us.

Jesse and grace getting Clidastes block ready for jacketing

The specimen was safely loaded in the truck by headlight, which also made for a really interesting drive through farm fields in the dark at the end of a 14 hour day. Prep is going on right now, so stay tuned to see how this cute little mosasaur turns out!

Digging the middle half of a Triceratops

We've finished the Triceratops dig that I announced in my last blog post. We got pretty much everything from the rear of the neck to the back of the hips, minus the limbs. It looks like the specimen was well laid out in order, unfortunately with the head end going off the edge of the cliff. Just a couple thousand years too late, but oh well. There was an unconformity at the top of the site that destroyed the higher bones, including shearing the bottom 4/5 of the femur away. Sometimes nature isn't nice to us. Enjoy the pics!

Scary bobcat driving to get rid of overburden

Mike not finding anything, Jacob on the hips

Naptime in the shade while employees roast

Hips isolated

Cap jacket on hips and attempting to recover a whole rib

Big jacket done after a seriously long day

Prep on the main hips block is going slowly, but we hope to have this monster chunk of bone out on display later this week.

Progress on the jacket but still lots to go

Hell Creek: What I found on my summer "vacation"

We've just returned to the lab from a 2 week expedition to the Hell Creek Formation in South Dakota. The weather was very hot, the bugs were out in force, and I had a grand total of one shower during our stint in the wilds. Here's a bit of what we found.

Thescelosaurus claw

Theropod tibia

partial triceratops skull before excavation

Finds were a bit sparse in week one. Lots of hiking and lots of incredibly bare outcrops. Occasionally I founds some Champsosaurus bones or gar scales, but for the most part it was just a bit depressing. Then I made my big "find" of the first half of the trip: a Pachycephalosaurus dome!

Not a pretty dome

but they're so rare

Just when things were starting to look bleak, I found 2 Triceratops sites a few days apart. The first so far is just a pile of ribs (we will expand the dig later to see if more is present) but was in a great location where we could drive the truck to, no overburden, really ideal.

We can always use more parts

The second one, in true Anthony fashion, I found by tracing a bone fragment to the top of a 50-60 foot cliff that had bones sticking out of it. I knocked out a very small excavation the first day and kept running into more bones. Jacob and I returned for a few more very hot (120 degree plus) excavation days and found over 20 bones so far. A few were recovered, and we will return to the site in a few weeks with a bobcat to move some serious dirt and continue the excavation. So far it's mostly really big vertebrae, ribs, and girdle elements, though there is some skull and rooted teeth too. Fingers crossed for a complete-ish specimen!

Looking down from the site. Part of the humerus can be seen poking out

Looks like quite a climb up to the site

Dorsal vertebra awaiting excavation

Digging more holes in Kansas

It's been quite a while since the last update, but that's because of all the field work we've been doing in western Kansas. Hell, I feel like I've been digging deeper holes than Kansas' Governor. Ha! Biting political humor.

In any case, Jacob just released a video that has a few awesome action shots of me staring at the ground, and a really ugly (well, even uglier than usual) Xiphactinus that I found before we started working on it. Check it out and don't forget to subscribe to his youtube channel or the Dinosaur Nerds website so you can see all kinds of boring thing like me complaining about mosasaurs.

Giant Oviraptor Tracks from the Hell Creek

It's been known for years that there are oviraptor-like dinosaurs found in the Hell Creek Formation. We find isolated elements mostly. A pubis here, a claw there. Small snapshots into their world, but they don't answer deeper questions like how big they got, how they moved, where they lived (instead of just where their remains ended up).

Skeleton of the new Hell Creek Ovi

In 1997 Mike Triebold was scouting on private land in Harding County, SD for dinosaurs. He came across a strange looking concretion. It looked a bit like a footprint, but as we know, concretions can take on all kinds of shapes. Looking closer, there was another concretion, in the same shape nearby. Then another and another, all in a line. A small excavation was started into the nearby outcrop, and the line of concretions continued. Though the overburden was getting too deep to chase them futher, it is likely there are even more still at the site. Mike recovered the specimens and made them available for research, which will be published on shortly.

Tracks in situ. The largest are nearly 60cm (2ft) across

Excavation of tracks

The concretions have now been identified as a preserved as the trackway of a giant North American oviraptorid, much larger than the specimens that we have skeletal remains for. The trackway shows how fast the animal was moving and even what kind of muck it was trudging through. We made molds and casts of the best ones, I'm thinking it may be a great addition to our ovi display in the exhibit hall.

Field season in full swing

Sorry for the lack of updates lately. We've been in South Dakota and Montana working the Hell Creek and Judith River Formations respectively.

Jacob for scale before we open a Triceratops site

South Dakota had seen its fair share of rain, where we got rained out more in two weeks there than in my entire previous decade of Hell Creek digging combined. We pulled a few Triceratops bones and finished evaluating a few sites before moving on north.

Nanotyrannus teeth collected from a single lag deposit

In Montana, our main focus has been opening the Avaceratops dig again and pulling out more of the animal. Lots of bobcat work The back wall of the quarry is nearing 10 feet tall now. Hopefully we're ending the dig soon so we can explore... Enjoy the photos!

Huge fault in the Hell Creek. Jacob somewhere to the left

It's the greenest I've ever seen in July for Montana in the JRF

I cut the steep part of the bobcat road. It's pretty scary to use. 

Duckbill butt I found a few years ago. Finally excavated this year.

After excavation and pedestaling

Part of the Avaceratops braincase

Ava site a few weeks back, before Bobcat work to push the wall back

More with Avaceratops

We just got back from the final dig of the 2012 season in the Avaceratops quarry. The weather was outstanding with sun, highs in the 80s and lows near 40. Getting a little chilly in my tent, but nothing uncomfortable.

A few of the epoccipitals. Not very big or pointy.

When we decided to take a jackhammer to the overburden we had only recovered some postcranial elements and one part of the frill, the right squamosal. Many hours later we had blasted out several tons of rock from above our bone layer, and were able to get digging.

The smallest group jacket, with at least 4 bones

To our surprise, nearly all of the bones found in this expansion of the quarry were disarticulated parts of the skull, including some parts that had never been seen before in this genus. We recovered (so far) 8 epoccipitals, the predentary, and a complete jugal (all new), plus both postorbital horns, a left dentary, nasals, maxillae, the other squamosal, and both splenials. There are even more bones in the blocks that we couldn't get a good look at yet, so completeness should further increase.

left Nasal, very well preserved

inside of right maxilla, with a few teeth still in place

I am interpreting the site as a logjam along the southern edge of the quarry, made of (now) carbonized conifer trunks and surprisingly the limb of a very large hadrosaur, the femur measuring a whopping 1.25m long. Check back for more photos as prep continues, and stop by the lab for a look if you are in Woodland Park!

Sometimes you get the Trike, sometimes it gets you

Jacob and I are back from a second trip to the Hell Creek, working on some sites we discovered on the first trip. We spent the majority of our efforts on the site that produced the left brow horn form the first trip.

Beginning of the dig. Chunky bone fragments circled in orange paint.

We expanded the excavation to the north by about 8 feet, tracing a few bone fragments. The overburden was low, and digging relatively easy, but the bone exposed were rounded isolated small chunks. Not especially promising.

Braincase with distinctive ball of the occipital condyle

As we worked back closer to where the brow horn was found, we started encountering more recognizable bones. Unfortunately, the skull was all that was present, and even then it was partial. In the end we recovered a squamosal, predentary, braincase and maxilla, along with some fragile fragments that will be worked on in the lab.

First batch of bones jacketed, waiting for plaster to cure

End of the dig. The generator and electric jackhammer was a real back-saver!

Headed back out in a few weeks, hopefully more luck then!