Last Wednesday, May 9, Brian Engh and I bombed out to Utah for a few days of paleo adventures. Here are some highlights from our trip.

We started at a Triassic tracksite on Thursday. But I’m not going to post any pictures of the tracks – those will be coming to a Brian Engh joint near you in the future. Instead, I’m going to talk about this little male collared lizard whose territory included the tracksite. He was fearless – didn’t want to run off and leave us yahoos wandering around his patch of desert unsupervised. Brian tickled his chin at one point.

Getting this close to him is how I got shots like this one:

Click through to the big version, it’s worth it.

One more shot of a couple of cool desert dwellers. I was so fixated on the lizard that I didn’t realize until later that Brian was in the frame, taking a much-needed hydration break.

On Friday we had a temporary breaking of the fellowship. I went to Fruita, Colorado, to visit the Dinosaur Journey museum. You’ve seen photos from DJ here before, from the 2014 Mid-Mesozoic Field Conference and the 2016 Sauropocalypse. Here’s an apatosaur pubis with some obvious bite marks on the distal end. This is on display next to a similarly-bitten ischium, which is shown in the MMFC14 post linked above.

Here’s a big apatosaur cervical, in antero-ventral view, with a dorsal rib draped over its left side. The cervical ribs are not fused in this specimen, so it was probably still growing. Here’s a labeled version:

The short centrum and nearly-vertical transverse processes indicate that this is a pretty posterior cervical, possibly a C13 or thereabouts. This specimen was over the fence in the exhibit area and I couldn’t throw a scale bar at it, but I’d describe it as “honkin'”. Like most of the apatosaur material at DJ, this vert is from the Mygatt-Moore Quarry.

Of course the real reason I was at Dinosaur Journey was to see the Snowmass Haplocanthosaurus that John Foster and I described back in 2014. You may remember that its caudal vertebrae have wacky neural canals. You may also have noticed a recent uptick in the number of posts around here about wacky neural canals. The game is afoot.

But as cool as they were, the Triassic tracks, the collared lizard, and even the Snowmass Haplo were only targets of opportunity. Brian and I had gone to Utah for this:

That photo was taken by Paige Wiren of Salt Lake City, on the day that she discovered that bone eroding out of a riverbank, just as you see it.

Here’s Paige with the element, which proved to be the left femur of an apatosaurine sauropod. It’s face down in these photos, so we’re looking at the medial side. The articular head is missing from the proximal end – it should be facing toward Paige’s right knee in the above photo – but other than that and a few negligible nicks and dings, the femur was complete and in really good shape.

Paige did the right thing when she found the femur: she contacted a paleontologist. Specifically, she asked a friend, who in turn put her in touch with Carrie Levitt-Bussian, the paleontology Collections Manager at the Natural History Museum of Utah. Based on Paige’s photos and maps, Carrie was able to identify the element as a dinosaur femur, probably sauropod, within the territory of the BLM Hanksville Field Office. John Foster, the Director of the Museum of Moab, has a permit to legally collect vertebrate fossils from that area, and he works on sauropods, so Carrie put Paige in touch with John and with ReBecca Hunt-Foster, the district paleontologist for the BLM’s Canyon Country District in Utah.

Now, I know there’s a lot of heated rhetoric surrounding the Bureau of Land Management, but whatever your political bent, remember this: those are our public lands. Therefore the fossils out there are the collective property of all of us, and we should all be upset if they get poached or vandalized. Yes, that is a big problem – the Brontomerus type quarry was partially poached before the bones we have now were recovered, and vandalism at public fossil sites in Utah made the national news while we were out there.

So that’s what we went to do: salvage this bone for science and education before it could be lost to erosion or asshats. Brian and I were out there to assist John, ReBecca, and Paige, who got to see her find come out of the ground and even got her hands dirty making the plaster jacket. Brian and John headed out to the site Friday morning and met up with Paige there, and ReBecca and I caravanned out later in the day, after I got back from Fruita.

But I’m getting ahead of myself a bit. We didn’t have to jacket the whole thing. It had naturally broken into three pieces, with thin clay infills at the breaks. So we just slid the proximal and middle thirds away as we uncovered them, and hit any loose-looking pieces with consolidant. The distal third was in more questionable shape, so we did make a partial jacket to hold it together.

We also got to camp out in gorgeous country, with spectacular (and welcome) clouds during the day and incredible starry skies at night.

We floated the femur out of the site using the Fosters’ canoe at the end of the day on Saturday, and loaded up to head back to Moab on Sunday. At one point the road was empty and the sky was not, so I stood on the center line and took some photos. This one is looking ahead, toward I-70 and Green River.

And this one is looking behind, back toward Hanksville.

Here are John and Brian with the femur chunks in one of the back rooms of the Museum of Moab. The femur looks oddly small here, but assembled it was 155 cm (5’1″) long and would have been 160 (5’3″) or more with the proximal head. Smaller than CM 3018 and most of the big mounted apatosaurs, but nothing to sneeze at.

What happens to it next? It will be cleaned, prepped, and reassembled by the volunteers and exhibit staff at the Museum of Moab, and eventually it will go on public display. Thousands of people will get to see and learn from this specimen because Paige Wiren made the right call. Go thou and do likewise.

That was the end of the road for the femur (for now), but not for Brian and me. We had business in Cedar City and St. George, so we hit the road Sunday afternoon. Waves of rainclouds were rolling east across Utah while we were rolling west, with breaks for sunlight in between. I miiiight have had to swerve a couple of times when all the scenery distracted me from driving, and I definitely made an obnoxious number of stops to take pictures.

I don’t remember which scenic overlook this was, but it was a pretty darned good view. This is another one that will reward embiggening – check out those mesas marching off into the distance.

In Cedar City we were guests of Andrew R.C. Milner, Site Paleontologist and Curator at the St. George Dinosaur Discovery Site at Johnson Farm (SGDS). We spent most of Monday at SGDS, getting our minds comprehensively blown by the amazing trace and body fossils on display. It was my first time visiting that museum, but it sure as heck won’t be the last.

I didn’t take nearly enough photos in St. George – too busy helping Brian do some filming for a future project – but I did get this gem. This is a Eubrontes track, from a Dilophosaurus-sized theropod. This is a positive track, a cast of the dinosaur’s foot made by sandy sediment that filled the natural mold formed when the dino stepped into mud. The high clay content of the mud recorded the morphology of the foot in fine detail, including the bumps of individual scales on the foot pads. The vertical streaks were cut into the side of the track by similar scales as the animal’s foot pushed into the mud.

The full story of the Johnson Farm tracks and trackmakers is beautifully told in the book Tracks in Deep Time: The St. George Dinosaur Discovery Site at Johnson Farm, by Jerry Harris and Andrew Milner. I hadn’t read it before, so I picked up a copy in the gift shop and I’ve been devouring it. As a professional scientist, educator, and book author myself, I’m jealous of what Jerry and Andrew produced – both the text and the abundant full-color illustrations are wonderfully clear, and the book is well-produced and very affordable.

From St. George we hit the road home, and rolled into Claremont just before midnight on Monday. It was a whirlwind tour – 1800 miles, three museums, and two fossil sites in six days – and my brain is still fizzing with all of the things we got to see and do.

One of the many pros of having a professional artist as a friend is that minimal hospitality, like letting him crash on my couch, is sometimes rewarded with original art. Brian was already gone when I got up Tuesday morning, but this was waiting for me on the dining room table. (Want your own? Help Brian make more monsters here.)

I owe plenty of thanks myself: to the Foster and Milner families for their near-maximal hospitality, to Julia McHugh of Dinosaur Journey for assistance in collections, to Diana Azevedo, Jalessa Spor, Jerry Harris, and the rest of the SGDS staff for being such gracious hosts, to Brian for being such a great friend and traveling companion, and most of all to Paige Wiren for finding the apato femur and helping us save it for science. You’re all top-notch human beings and I hope our paths cross again soon.

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I was in Philadelphia and New York last week, visiting colleagues on the East Coast and getting in some collaborative research. Much more to say about that in the future – even just the touristy stuff will fill several posts.

One highlight of the trip was visiting the Academy of Natural Sciences in Philadelphia last Friday. Ted Daeschler (of Tiktaalik fame) and Jason Poole (who illustrated this sweet book) were my generous hosts and I got to see a ton of cool stuff both out on exhibit and behind the scenes. Seriously, I could post for a month just on the Academy visit.

A personal highlight for me was seeing the cervical vertebrae of the sauropod dinosaur Suuwassea on exhibit. They are in a glass case and you can get around them pretty well to see a lot of anatomy. At first I was pumped to get nice color photos of all the vertebrae from up close and from multiple angles. Then I thought, “Huh, maybe I should just shoot a video.” So I did. Here you go, four minutes of hot sauropod vertebra action:

Back in 2009, I posted on a big cervical series discovered in Big Bend National Park. Then in 2013 I posted again about how I was going to the Perot Museum in Dallas to see that cervical series, which by then was fully prepped and on display but awaiting a full description. Ron Tykoski and Tony Fiorillo (2016) published that description a couple of years ago, and after almost five years it’s probably time I posted an update.

I did visit the Perot Museum in 2013 and Ron and Tony kindly let me hop the fence and get up close and personal with their baby. I got a lot of nice photos and measurements of the big specimen. It’s an impressive thing. Compared to the other big sauropod cervicals I’ve gotten to play with, these vertebrae aren’t all that long – the two longest centra are about 80cm, compared to ~120cm for Sauroposeidon, Puertasaurus, and Patagotitan, and 137cm for Supersaurus (more details here) – but they are massive. According to the table of measurements (yay!) in Tykoski and Fiorillo (2016), which accord well with the measurements I took when I was there, the last vert is 117.5cm tall from the bottom of the cervical rib to the top of the neural spine, 98.4cm wide across the diapophyses, and has a cotyle measuring 29cm tall by 42cm wide. Here it is with me for scale:

I guarantee you, standing next to that thing and imagining it being inside the neck of a living animal is a breathtaking experience.

I failed in my mission in one way. In a comment on my 2013 post, I said, “I’ll try to get some good lateral views of the mount with as little perspective as possible.” But it can’t be done – the geometry of the room and the size of the skeleton don’t allow it, as Ron noted in the very next comment. There is one place in the exhibit hall where you can get the whole skeleton into the frame, and that’s a sort of right anterolateral oblique view. Here’s my best attempt:

So, this is an awesome specimen and you should go see it. As you can see from the photos, the vertebrae are right on the other side of the signage, with no glass between you and them, so you can see a lot. The rest of the exhibits are top notch as well. Definitely worth a visit if you find yourself within striking distance of Dallas.

Reference

Tykoski, R.S. and Fiorillo, A.R. 2016. An articulated cervical series of Alamosaurus sanjuanensis Gilmore, 1922 (Dinosauria, Sauropoda) from Texas: new perspective on the relationships of North America’s last giant sauropod. Journal of Systematic Palaeontology 15(5):339-364.

Back in the spring of 1998, Kent Sanders and I started CT scanning sauropod vertebrae. We started just to get a baseline for the Sauroposeidon project, but in time the data we collected formed the basis for my MS thesis, and for a good chunk of my dissertation as well. Mostly what we had available to scan was Morrison material. Between imperfect preservation, inexpert prep (by WPA guys back in the ’30s), and several moves over the decades, most of the verts from the Oklahoma Morrison have their neural spines and cervical ribs broken off. One of the first things I had to figure out was how to tell broken vertebrae of Camarasaurus from those of Apatosaurus (at the time; Brontosaurus is back in contention now). Here’s a thing I made up to help me sort out cervical centra of Camarasaurus and whatever the Oklahoma apatosaurine turns out to be. It’s a recent production, but it embodies stuff from my notebooks from 20 years ago. Should be useful for other times and places in the Morrison as well, given the broad spatiotemporal overlap of Camarasaurus and the various apatosaurines.

For a related thing in the same vein, see Tutorial 30: how to identify Morrison sauropod cervicals.

More elephant seals soon, I promise.

UPDATE 20 Feb 2018

Ken Carpenter sent this by email, with a request that I post it as a comment. Since it includes an image, I’m appending to the post, because it makes an important point that I neglected to mention.

Camar post cerv

Ken: Sorry, Matt. Not so easy. The last cervical of Camarasaurus from the Cleveland Lloyd Quarry is more apatosaurine-like than Camarasaurus-like based on your posting. Note the position of both zygapohyses with both ends of the centrum.

My response: Yes, good catch. I meant to say in the post that my distinguishing characters break down at the cervico-dorsal transition. Even so, in this Cleveland Lloyd vert the postzyg is still forward of a line drawn directly up from the cotyle. I’ve never seen that in an apatosaurine–going into the dorsal series, the postzygs tend to be centered over a line projected up from the rim of the cotyle. (If anyone knows of counterexamples, speak up!)

For distinguishing cervico-dorsals, apatosaurines tend to have much taller neural spines than Camarasaurus, and this carries on through the rest of the dorsal series. In apatosaurine dorsals, the height of the spine above the transverse processes always equals or exceeds the height of the arch below the transverse processes. In Camarasaurus, the height of the dorsal neural spines is always less than or equal to the height of the arch. The shapes of the spines are fairly different, too. Maybe that will be the subject of a future post.

 

As part of a major spring cleaning operation that we started the first week of January, this week I opened the last two boxes left over from when we moved into our current house. One of them had a bundle of framed art. I knew most of what was in there before I opened the box, but I had somehow completely forgotten about this. I must have gotten it framed in late 90s, and it hung on the walls of our apartments in Norman and Santa Cruz. At some point it went into a box, and I forgot it even existed.

This is the first technical drawing I ever attempted of OMNH 53062, which would later become the holotype of Sauroposeidon. I drew it for my poster at the 1997 SVP meeting in Chicago, and it went on to become Figure 5 in my undergraduate thesis (which is preserved for posterity here). I’d do other, better drawings of the specimen in later years, but this one came first.

I know I’m biased, but that second vertebra in the preserved series, which I interpreted as C6 back when, will probably always be the most gorgeous natural object on the planet in my book. I don’t expect anyone else to feel the same. I worked on that specimen for three years – some of it seeped into my soul, and vice versa. Then again, I don’t care how jaded you are about long vertebrae, that one is still a pretty arresting sight.

For a much more recent take on the appearance of the Sauroposeidon vertebrae, see this post.

There’s a new paper out, describing the Argentinian titanosaur Mendozasaurus in detail (Gonzalez Riga et al. 2018): 46 pages of multi-view photos, tables of measurement, and careful, detailed description and discussion. But here’s what leapt out at me when I skimmed the paper:

Gonzalez Riga et al. (2018: figure 6). Mendozasaurus neguyelap cervical vertebra (IANIGLA-PV 076/1) in (A) anterior, (B) left lateral, (C) posterior, (D) right lateral, (E) ventral and (F) dorsal views. Scale bar = 150 mm. Sorry it’s monochrome, but that’s how it appears in the paper.

Just look at that thing. It’s ridiculous. In our 2013 PeerJ paper “Why Giraffes have Short Necks” (Taylor and Wedel 2013), we included a “freak gallery” as figure 7: five very different sauropod cervicals:

Taylor and Wedel (2013: figure 7). Disparity of sauropod cervical vertebrae. 1, Apatosaurus “laticollis” Marsh, 1879b holotype YPM 1861, cervical ?13, now referred to Apatosaurus ajax (see McIntosh, 1995), in posterior and left lateral views, after Ostrom & McIntosh (1966, plate 15); the portion reconstructed in plaster (Barbour, 1890, figure 1) is grayed out in posterior view; lateral view reconstructed after Apatosaurus louisae (Gilmore, 1936, plate XXIV). 2, “Brontosaurus excelsus” Marsh, 1879a holotype YPM 1980, cervical 8, now referred to Apatosaurus excelsus (see Riggs, 1903), in anterior and left lateral views, after Ostrom & McIntosh (1966, plate 12); lateral view reconstructed after Apatosaurus louisae (Gilmore, 1936, plate XXIV). 3, “Titanosaurus” colberti Jain & Bandyopadhyay, 1997 holotype ISIR 335/2, mid-cervical vertebra, now referred to Isisaurus (See Wilson & Upchurch, 2003), in posterior and left lateral views, after Jain & Bandyopadhyay (1997, figure 4). 4, “Brachiosaurus” brancai paralectotype MB.R.2181, cervical 8, now referred to Giraffatitan (see Taylor, 2009), in posterior and left lateral views, modified from Janensch (1950, figures 43–46). 5, Erketu ellisoni holotype IGM 100/1803, cervical 4 in anterior and left lateral views, modified from Ksepka & Norell (2006, figures 5a–d).

But this Mendozasaurus vertebra is crazier than any of them, with its tiny centrum, its huge, broad but anteroposteriorly flattened neural spine, and its pronounced lSPRLs.

I just don’t know what to make of this, and neither does Matt. And part of the reason for this may be that neither of us has had that much to do with titanosaurs. As Matt said in email, “Those weird ballooned-up neural spines in titanosaurs kind of freak me out.” And I could not agree more.

And of course as sauropodologists, we really should familiarise ourselves with titanosaurs. There are a lot of them, and they account for a lot of sauropod evolution. Someone recently made the point, either in an SV-POW! comment or on Facebook, that titanosaurs may be to sauropods what monkeys and apes are to primates: a subclade that is way more diverse than the rest of the clade put together.

It’s starting to look like an extreme historical accident that Camarasaurus, diplodocines and brachiosaurids — all temporally and/or geographically restricted groups — were the first well-known sauropods, and for decades defined our notion of what sauropods were like. Meanwhile, the much more widespread and long-surviving rebbachisaurs and titanosaurs were poorly understood until really the last 25 years or so. For the first century of sauropodology, our ideas about sauropods were driven by weird, comparatively short-lived outliers.

That our appreciation of titanosaur diversity has come so late says something about how our discovery of the natural world is more to do with geopolitics and the quirks of exploration than what’s actually out there. Sauropods were defined by diplodocids for so long because that’s what happened to be in the ground in the exposed rocks of North America, and that’s where the well-funded museums and expeditions were.

We at SV-POW! towards have often wondered how different our idea of what dinosaurs even were would be if the Liaoning deposits had been available to Buckland, Mantell, and Owen. It seems like that unavoidable that, if they’d first become familiar with feathered but osteologically aberrant (by modern standards) birds, one of two things would have happened. Either they would either have never coined the term “Dinosauria” at all, recognizing that Megalosaurus (and later Allosaurus and Tyrannosaurus) were just big versions of their little feathered ur-birds. Or they would have included Dinosauria as a primitive subclass of Aves.

References

  • González Riga, Bernardo J., Philip D. Mannion, Stephen F. Poropat, Leonardo D. Ortiz David and Juan Pedro Coria. 2018. Osteology of the Late Cretaceous Argentinean sauropod dinosaur Mendozasaurus neguyelap: implications for basal titanosaur relationships. Zoological Journal of the Linnean Society, 46 pages, 28 figures. doi:10.1093/zoolinnean/zlx103
  • Taylor, Michael P., and Mathew J. Wedel. 2013. Why sauropods had long necks; and why giraffes have short necks. PeerJ 1:e36. 41 pages, 11 figures, 3 tables. doi:10.7717/peerj.36

 


Note. This post contains material from all three of us (Darren included), harvested from an email conversation.

 

Here’s BYU 12866, a mid-cervical of a neosauropod from Dry Mesa Quarry. It’s cataloged as Brachiosaurus, an identification I’ve never found any compelling reason to doubt. It’s definitely brachiosaurid, and for now Brachiosaurus is the only game in town for the Late Jurassic of North America. I expect that will change when more and better material comes to light, based on the different coracoid shapes of the Brachiosaurus holotype and the “Ultrasauros” scapulocoracoid.

I reckon it’s probably a C5 or so, based on its proportions and comparisons with Giraffatitan (for example).

As you can see, it’s a bit distorted, sheared over with the dorsal side to the right and the ventral side to the left.

I don’t think there’s any major anterior/posterior shearing – the zygs are set forward of their respective centrum ends by about the same amount in this specimen as in Giraffatitan.

Kent Sanders and I CT scanned this vert back in the day and those scans made it into several papers, including Wedel et al. (2000b) on Sauroposeidon and Wedel (2005) on sauropod pneumaticity and mass estimates.

I have the original, uncropped, full-res photos, and I’ll probably get them posted at some point (faster if people bug me to do so, so speak up in the comments if you want them). But for now I’m sticking to getting stuff posted quickly, easily, and regularly, and I found these as-is on my hard drive, so here we are.

References