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

Reconstructing Chelosphargis: What to do with a pile of bones

We spend a lot of time in Kansas hunting for specimens in the Niobrara chalk. A whole lot of time. Luckily the soft chalk erodes pretty quickly so we also find a whole lot of stuff. Occasionally though, other people also get lucky and we'll happily take the specimen off their hands. In early 2015 this exact scenario played out. You may have seen the result at our display booth at SVP this year in Salt Lake City, overshadowed by our exciting mount of our Daspletosaurus "Pete III"

Curator shadow selfie while digging in Kansas recently

A poorly collected turtle specimen from the chalk was being shown around looking for a buyer, While the collection techniques caused some damage to the fossil, it was plain to see a fairly complete tiny Protostegid was encased in the slabs of yellow rock.

So, this is how we got it. Clearly not how we would collect a specimen.

Most importantly, almost all of the skull was there, which is really nice. We immediately acquired the specimen and prepared the parts. Quickly it became evident we had a older subadult specimen of the relatively rare taxon Chelosphargis advena, an 84 million year old relative of the much larger Protostega and Archelon.

The parts after prep

Skull partway through prep

As you can see, most of the animal was there, in fact it's one of the most complete Chelosphargis specimens ever discovered. But what do you do with a pile of bones once they're all prepared? We're one of the few places with the knowledge, experience and capability to do a complete cast restoration without damaging the original bones. The first step was to mold everything as-is, so we can have parts (sometimes even multiples) to work with.

Cast skull copies getting cut and shaped to take out distortion

Distortion is taken out of the plastic and missing parts are either fabricated from similar ones from this animal, scanned in and resized from other specimens, or in rare cases done the old way with sculpting from reference material.

Carapace getting parts added and completed

The restored parts are then molded again in units so that we can make our final copy and offer it to museums and the general public as a highly detailed cast skeletal mount, perfect for display anywhere. The entire project only takes a few weeks, but the result is pretty phenomenal!

Final product!

No love for Ichthyodectes?

It seems like nearly every year a new book, film, or television program comes out featuring the long-dead seaway that covered most of the central part of North America back in the late Cretaceous. Invariably they have cameos featuring Xiphactinus, Cretoxyrhina, Protosphyraena, and even the "bait fish" Gillicus and Enchodus. They have mosasaurs, pterosaurs and even sea turtles. If you didn't follow the science closely, you'd understandably figure that's about all that lived in that shallow sea.

Our cast specimen restored in all its 3d glory

Truth be told, there were probably a few hundred types of fish in that seaway. Dr. Kenshu Shimada made a decent attempt to catalog all of them a few years ago, but like all good science on the Niobrara, it was getting out of date almost as soon as it was published. It's really amazing that 120 years after collecting work began in Western Kansas, new critters are still being found. I'm not going to go into details on them (I'll save them for other blog posts) and instead focus on this fish that is criminally underrepresented in the literature and online.

RMDRC 11-018, a massive 9 foot Ichthyodectes

If it's Wikipedia entry were any indication of its importance, what does the text containing a whopping total of 89 words tell you? That's right, 89 whole words, some of which are even talking about other related fish. Lame.

Some of the teeth of RMDRC 11-018. Yikes

Ichthyodectes, a fish with moderately terrifying teeth and with a body length approaching 9 feet, it's not cheered on much. Sure it's pretty common in the Niobrara, but it's also basically a pocket Xiphactinus (see, using the Wikipedia trick of talking about it's cooler cousin to gin up some interest). An average scouting season for us will find 5 or so specimens identified through cranial material. Probably more, but postcranially all ichthyodectids of about the same size pretty much look identical.

RMDRC 14-027, excavated with a film crew, watch for it soon on TV!

Perhaps a big reason as to why Ichthyodectes gets so little love is that there are so few specimens on display in museums, even fewer ones that look, um, not silly. Perhaps we need more museums to decide that decent specimens of lesser known fossil fish of the Niobrara are just as important for display as mosasaurs or sharks or Xiphactinus. Maybe I'm just asking for too much. In any case, I've pretty much doubled the amount of useful Ichthyodectes pics on the interwebs, so I'll count it as a win.

Avaceratops Skull Resto

Cast mount of the holotype Avaceratops in Philadelphia

So after a year and a half of digging and preparation, what do you do with a big pile of bones? Put them together! At long last, our Avaceratops project is moving forward and is surprisingly starting to look like something. Avaceratops is a fairly poorly known animal, with only 2 partial and fragmentary skulls discovered before this one. Ours is filling in lots of gaps since 1: we have more bones than were known before and 2: the bones that we have are more or less complete, not busted up. This adds a degree of difficulty to the project since all the restorations done before made a few educated assumptions about their missing bits, and not all of those were accurate.

An older bone map of the skull bones we thought we recovered, based on an image by Scott Hartmann

Jaw bones both real and 3d printed

Where to start though? In treating this like a giant model kit, we first decided to make all the parts we needed. There will be 60 individual bones to deal with. While we have the lions share of those, we do not have them all. The first step is to mold all the original elements and cast them in plastic. This enables us to mount them and take distortion out without destroying any of the real fossil. Second we identified all the elements that we had one side of and needed the other. Those elements were laser scanned, mirror imaged in software, then printed out in plastic on one of our 3d printers. Lastly, some elements were flat out missing. Those were fortunately few, but they ended up getting sculpted.

So, let's begin with some parts. Boot for scale

Once the parts were poured, we cut apart a few casts where the bones were glommed together and it was too dangerous to try to pry the fossils apart. After fitting a few parts, some needed to get cut or bent to fit how they were supposed to, taking millions of years of crushing and distortion out. This is much trickier than it sounds. Our frontals were squished just enough in the ground that when the brow horns were attached to the mount, the tips crossed each other. That's probably not how they went in life. The casts were then adhered together into subassemblies ready for molding.

Where we are today.

Work is still ongoing but we hope to be done in the next week or so with the heavy work. Once the molding is done, the final product will be just 5 parts. Much easier to put together than 60.

The Little Protostega is Restored!

A final follow-up on the project that I had mentioned in the last update. The project is "finished" for now, all molding is complete and the first two prototypes have been assembles and packed.

Cast bones and skull restoration before assembly

We molded hundreds of individual bones for this project. Those cast parts were restored, put into subassemblies, then remolded to produce the final cast. The cast preserves all the pathologic and taphonomic detail, including what appears to be puncture wounds from predation by one of the many mosasaurs in the Niobrara. I blame it on Tylosaurus.

Prototype #2 flying by the green screen

Prototype #1

Prototype #1 with curator for scale

Amazingly, the whole animal now goes together from a trimmed cast to a final project in less than a week. The first specimen was given to the Sternberg Museum at Fort Hays State University to accompany the original specimen now safely in their collections. The second cast will be on display beginning next week at the Tucson gem and mineral show, at the 22nd street show. Come by and check it out!

A little photographic update: Xiphactinus Mildred

Jacob and Lisa keep plugging along on the gigantic mount of the huge 18 1/2 foot long Xiphactinus audax "Mildred". Basic assembly except for the fins are now finished, hopefully soon we will be able to rotate the mount to its upright position, working on a 5 foot high table is not exactly fun.

The things you find when you work on stuff

Mildred's skull, with blue tape to mark parts that need to be removed

We've almost entirely finished the preparation of RMDRC 11-021 "Lois", the last parts donor fish for our reconstruction of RMDRC 08-004 "Mildred". We've been going through some of the pieces of chalk that fell out of the huge main jacket when it partially collapsed when we flipped it for removal from the digsite. Sometimes these things happen, especially when the chalk is weathered and fractured.

Feathery and fine gill structures articulated with the arches

Surprisingly one of the chalk pieces produced something very rare: the actual preserved gill structure of this Xiphactinus. Usually with most Xiphactinus specimens, the disarticulation of the skull by scavengers results in these delicate structures being lost. On articulated skulls, they are likely present however no one ever starts removing bones to investigate if they are indeed there. For now they remain pretty rare things. We won't be using these in our restoration, hopefully we can find a good home to donate them to.

Jacob and Lisa fastening plywood to the steel tube frame

In other news on the reconstruction front, we've finished building the frame for Mildred. 21 feet long, 7 feet tall, it's going to be 150 square feet of big bad X-fish. Nearly time to put it on a rolling stand so we don't have to lift it ever again!

Nyctosaurus restoration finished!

Beautifully detailed specimen

We've added another flying critter to our family of casts. This time it's a restoration of a female Nyctosaurus gracilis. This is the smaller of the two flying reptiles found in the Niobrara Chalk of western Kansas, and by far the most rare. Contact me if you're interested in a copy. We're offering a substantial discount off of our introductory price through the end of August.

Top-ish view showing lack of wing claws

Look out for that Pteranodon!

Our restoration ended up with a wingspan of 7 feet. We'll be debuting the crested male specimen in a few weeks, so keep tuned for updates. Also come to the museum to see this specimen now proudly on display in out exhibit hall.

Just a Pretty Picture

Ok, maybe not so pretty because I've volunteered myself to be the RMDRC spokesmodel. Just consider yourself lucky I didn't accessorize with a bikini.

New Turtle Display Almost Done!

I just wanted everyone to know our new surrogate marine hall is about finished and ready to open, hopefully for this (cold) weekend. We've got quite a turtle-heavy display, featuring skeletons of Archelon, Protostega, Toxochelys, Prionochelys and the shell of Bothremys. Also on display is a mosasaur-bitten Toxochelys shell, RMDRC 08-003 "Kraigums" that I discovered last spring, as well as the only real bones of Megalocoelacanthus dobiei on public display anywhere, the youngest fossil coelacanth found. There are also many more marine touch stations too. Please stop by and let us know what you think!