Wednesday, September 16, 2015

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

Wednesday, August 26, 2015

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

Wednesday, July 29, 2015

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

Monday, June 22, 2015

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.

Wednesday, May 27, 2015

Our Xiphactinus dig featured on River Monsters: backstory

I really hope everyone got a chance to see the River Monsters season finale. Here's a teaser of Jeremy Wade Sharing a bit of what he had learned with us in the field digging up a Xiphactinus audax skeleton.

One of the things he alludes to has a funny backstory. When we first arrived at the site, the film crew's rental minivans couldn't get near where all the equipment needed to be. Not a huge problem, we transferred it to the bed of the bosses truck and away went the gear and most of the crew. I had been riding in vehicles way too much already that morning and decided I'd walk the easy 1/4 mile or so left to the site. Jeremy, the director and an assistant decided this was a good idea as well, so I was able to show them some things in the chalk on the way up. Mostly clams. Lots and lots of clams.
The site is on the opposite side of the butte in the background
Arriving near the digsite site, literally within 4 feet of where the boss parked the truck, while talking to Jeremy about how you have to be in the right place at the right time to find a specimen, I look down and see the face of a newly eroding Xiphactinus specimen poking out of the rock. I COULD NOT HAVE PLANNED IT BETTER. It's really not all that great, but our guests had never seen the discovery of a fossil before, and they seemed pretty thrilled about it. Happy I could oblige.
Can you see it? It's a beauty!
Back in the lab the next day we worked hard to begin the prep on the Xiphactinus specimen RMDRC 14-012, which we nicknamed "Jeremy". Unfortunately, all of that seems to have ended up on the cutting room floor.
Just a few people watching over my shoulder as I prep
Nevertheless, we went ahead and finished prep on "Jeremy". Not the prettiest one, and for the life of me I can't figure out how the face was nicely articulated but the entire braincase was spun off and away. Them's the breaks I guess. As for working with the River Monsters crew again? Name the time and place, they were superb.
I've seen worse

Sclerotics in place still!

Wednesday, May 20, 2015

See us on River Monsters this Monday!

I can't reveal too much until the air date, but I can now share that you'll be able to see Jacob, Mike and myself on the season finale episode of "River Monsters" starring Jeremy Wade!
Looking busy in the glory of the Blue Shirt
Jeremy came out to the field with us recently, then visited the museum, film crew in tow, to experience a fish dig in Kansas and what we do with the fossils once they return to the lab. It was a busy but fun couple of days with him and the crew from Icon Films. Hopefully what airs on Animal Planet features my good side!

Tuesday, May 5, 2015

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.