A life-size silhouette of the Snowmass Haplocanthosaurus, with Thierra Nalley, me, and Jessie Atterholt for scale. Photo by Jeremiah Scott.

Tiny Titan, a temporary exhibit about the Snowmass Haplocanthosaurus project, opened at the Western Science Center in Hemet, California, last night. How? Why? Read on.

Things have been quieter this year on the Haplo front than they were in 2018, for many reasons. My attention was pulled away by a lot of teaching and other day-job work–we’re launching a new curriculum at the med school, and that’s eaten an immense amount of time–and by some very exciting news from the field that I can’t tell you about quite yet (but watch this space). Things are still moving, and there will be a paper redescribing MWC 8028 and all the weird and cool things we’ve learned about it, but there are a few more timely things ahead of it in the queue.

One of the things going on behind the scenes this year is that Jessie Atterholt, Thierra Nalley, and I have been working with Alton Dooley, the director of the Western Science Center, on this exhibit. Alton has had a gleam in his eye for a long time of using the WSC’s temporary exhibit space to promote the work of local scientists, and we had the honor of being his first example. He also was not fazed by the fact that the project isn’t done–he wants to show the public the process of science in all of its serendipitous and non-linear glory, and not just the polished results that get communicated at the end.

Everything’s better cut in half. Photo by Jessie Atterholt.

Which is not to say that the exhibit isn’t polished. On the contrary, it looks phenomenal. Thanks to a loan from Julia McHugh at Dinosaur Journey in Colorado, most of the real fossils are on display. We’re only missing the ribs and most of the sacrum, which is too fragmentary and fragile to come out of its jacket. As you can see from the photo up top, there is a life-size vinyl silhouette of the Snowmass Haplo, with 3D prints of the vertebrae in approximate life position. Other 3D prints show the vertebrae before and after the process of sculpting, rescanning, and retrodeformation, as described in our presentation for the 1st Palaeontological Virtual Congress last year (that slideshow is a PeerJ Preprint, here). The exhibit also includes panels on “What is Haplocanthosaurus” and its relationships, on pneumaticity in sauropods, on the process of CT scanning and 3D modeling, and on the unusual anatomical features of the Snowmass specimen. The awesome display shown above, with the possibly-bumpy spinal cord and giant intervertebral discs reconstructed, was all Alton–he did the modeling, printing, and assembly himself.

Haplo vs Bronto. Thierra usually works on the evolution and development of the vertebral column in primates, so I had to show her how awesome vertebrae can be when they’re done right. Photo by Brittney Stoneburg.

My favorite thing in the exhibit is this striking comparison of one the Snowmass Haplo caudals with a proximal caudal from the big Oklahoma apatosaurine. This was Alton’s idea. He asked me if I had any photos of caudal vertebrae from really big sauropods that we could print at life size to compare to MWC 8028, and my mind went immediately to OMNH 1331, which is probably the second-largest-diameter vertebra of anything from all of North America (see the list here). It was also Alton’s idea to fill in the missing bits using one of Marsh’s plates of Brontosaurus excelsus from Como Bluff in Wyoming. It’s a pretty amazing display, and it turns out to have been a vehicle for discovery, too–I didn’t realize until I saw the verts side-by-side that the neural canal of the Snowmass Haplo caudal is almost as big as the neural canal from the giant apatosaurine caudal. It’s not a perfect comparison, because the OMNH fossil doesn’t preserve the neural canal, and the Como specimen isn’t that big, but proportionally, the Snowmass Haplo seems to have big honkin’ neural canals, not just at the midpoint (which we already knew), but all the way through. Looks like I have some measuring and comparing to do.

(Oh, about the title: we don’t know if the Snowmass Haplo was fully grown or not, but not all haplocanthosaurs were small. The mounted H. delfsi in Cleveland is huge, getting into Apatosaurus and Diplodocus territory. Everything we can assess in the Snowmass Haplo is fused, for what that’s worth. We have some rib chunks and Jessie will be doing histo on them to see if we can get ontogenetic information. I’ll keep you posted.)

Brian’s new Haplocanthosaurus restoration, along with some stinkin’ mammals. Photo by Jessie Atterholt.

Brian Engh contributed a fantastic life restoration of Haplocanthosaurus pro bono, thanks to this conversation, which took place in John Foster’s and ReBecca Hunt-Foster’s dining room about a month ago:

Brian: What are you drawing?

Me: Haplocanthosaurus.

Brian: Is that for the exhibit?

Me: Yup.

Brian (intense): Dude, I will draw you a Haplocanthosaurus.

Me: I know, but you’re a pro, and pros get paid, and we didn’t include a budget for paleoart.

Brian (fired up): I’m offended that you didn’t just ask me to draw you a Haplocanthosaurus.

Then he went to the Fosters’ couch, sat down with his sketchbook, and drew a Haplocanthosaurus. Not only is it a stunning piece on display in the exhibit, there are black-and-white printouts for kids to take and color (or for adults to take to their favorite tattoo artists, just sayin’). [Obligatory: this is not how things are supposed to work. We should all support original paleoart by supporting the artists who create it. But Brian just makes so damn many monsters that occasionally he has to kick one out for the heck of it. Also, I support him on Patreon, and you can, too, so at a stretch you could consider this the mother of all backer rewards.]

One special perk from the opening last night: Jessica Bramson was able to attend. Who’s that, you ask? Jessica’s son, Mike Gordon, found the first piece of bone from the Snowmass Haplo on their property in Colorado over a decade ago. Jessica and her family spent two years uncovering the fossils and trying to get paleontologists interested. In time she got in touch with John Foster, and the rest is history. Jessica lives in California now, and thanks to John’s efforts we were able to invite her to the exhibit opening to see her dinosaur meet the world. Stupidly, I did not get any photos with her, but I did thank her profusely.

A restored, retrodeformed caudal of the Snowmass Haplocanthosaurus, 3D-printed at life size for the exhibit. Photo swiped from the WSC Facebook page.

I owe a huge thanks to Alton Dooley for taking an interest in our work, and to the whole WSC crew for their hard work creating and promoting the exhibit. You all rock.

The exhibit will run through the end of March, 2020, at least. I deliberately did not show most of it, partly because I was too busy having fun last night to be diligent about taking photos, but mostly because I want you to go see it for yourself (I will do a retrospective post with more info after the exhibit comes down, for people who weren’t able to see it in person). If you make it out to Hemet, I hope you have half as much fun going through the exhibit as we did making it.

No time right now for me to dig into the interesting and important discussion on how we should orient vertebrae (here and here so far) – that will be coming soon. In the meantime, here’s something else.

As printed, in one of WesternU’s 3D printers.

Coming off the tray.

Cleaned up and in my hand. This is a 70% scale print, so a little smaller than the original, but all the important morphology is clear enough. For one thing, I can finally make sense of the dorsal views of the vertebra.

I have been astonished at how useful a 3D print can be as an aid to thought. The caudals of the Snowmass Haplocanthosaurus are among the smallest sauropod vertebrae I’ve spent a lot of time with, and they’re still heavy enough and fragile enough that I don’t just whip them out and twirl them around in my fingers. But I can do that with the 3D prints, and it really helps ram the morphology home in my brain. There are a thousand subtle things I might not otherwise have noticed if I hadn’t been able to turn those shapes over easily in my hand. Not to mention the other things you can do with prints, like physically sculpt on them without gooping up your fossils (we’re midway through step #8 from that post, BTW).

Anyway, back to Xeno. Mike reminded me that I have seen the actual specimen in person exactly once, very briefly during our 2005 visit to the NHM collections when I was over there for SVPCA. But it wasn’t Xeno yet, and we had other fish to fry, including a lot of pneumatic and possibly-pneumatic stuff for me to see and photograph for my dissertation. So I have to admit that it didn’t register. Being able to handle it now, so much that Mike has written about it snaps into focus. Not that his writing isn’t clear, there’s just a huge gulf between the best written description and holding a thing in your hands.

Why do I have this thing? Partly to educate myself, partly because it’s relevant to a current project, and partly because we may not be done with Xeno. Stay tuned.

Many thanks to Gary Wisser for setting up the print, and to Jeff Macalino for pulling it for me.

We don’t post on pterosaurs very often, but I’m making an exception for Caelestiventus. Mostly because I had the unusual experience of holding a life-size 3D print of its skull a few days before it was published. Brooks Britt and George Engelmann are both attending Flugsaurier 2018 in Los Angeles, and Brooks gave a talk on the new pterosaur on Friday. It’s from the Upper Triassic Saints & Sinners Quarry in far northeastern Utah, which has also produced theropods, sphenosuchian crocs (like 80 individuals to date, no exaggeration), drepanosaurs (I’ve seen the material and that paper is going to be mind-blowing whenever it arrives), and other assorted hellasaurs. Some of that material is figured in the Britt et al. (2016) paper on the Saints & Sinners Quarry (a free download from the link below). As far as I know, the Caelestiventus paper is the second big volley on the Saints & Sinners material, out of what will probably be a long stream of important papers.

Anyway, since we’ve just been discussing the utility of 3D printing in paleontology (1, 2), I thought you’d like to see this. Brooks did caution us that the 3D model was a work in progress, and he now thinks that Caelestiventus had a more convex dorsal skull margin, with the downward forehead dip in the version that got printed being less prominent or absent. You can see a slightly different version in the skull recon drawn by second author Fabio M. Dalla Vecchia, which he kindly released into the public domain here.

Otherwise the 3D print is pretty good. The big plate below the orbit is weird and from what I gather not present in other dimorphodontids. Because the Saints & Sinners material was buried in sand, which is relatively incompressible compared to mud and clay, it’s all preserved in three dimensions with essentially no crushing. Caelestiventus therefore yields new information about Dimorphodon micronyx, which has been known since 1859 but mostly from pancaked material.

Stay tuned (in general, not here necessarily) for more on the remarkable tetrapods of the Sants & Sinners Quarry – the next few years are going to be very exciting. And since this may be my first and last Flugsaurier post, many thanks to the organizers for making it such an engaging and enjoyable experience, especially Mike Habib, Liz Martin-Silverstone, and Dave Hone.

References