On Monday we visited the Prehistoric Museum in Price, Utah, the Cleveland-Lloyed dinosaur quarry, and sites in the Mussentuchit member of the Cedar Mountain Formation. Many thanks to Marc Jones for the photos.

1 - CEU Prehistoric Museum

In 2010, the College of Eastern Utah became Utah State University – Eastern, and the CEU Prehistoric Museum in Price is now officially the USU Eastern Prehistoric Museum. The dinosaurs in the center of exhibit hall are being remounted. These include Allosaurus, Stegosaurus, Camptosaurus (mounted, toward top of photo), and Camarasaurus (dismounted, on floor). Most of the mounts are either real material or casts of real material from the nearby Cleveland-Lloyd quarry.

The museum has many other exhibits besides the one shown above. The paleo wing alone covers two floors, and upstairs there are great displays on Cretaceous dinosaurs from the area, including Jurassic and Cretaceous ankylosaurs, a ceratopsian, and numerous tracks.

2 - Cleveland-Lloyd orientation

After leaving Price we went to the Cleveland-Lloyd dinosaur quarry, which has produced over 20,000 separate elements, including the remains of something like 50-60 allosaurs. The smallest ones are hatchlings–several elements from literally cat-sized baby allosaurs are known from the quarry.

3 - Mark Loewen teaching

Mark Loewen (right) talked to us about how the quarry might have formed, and what it’s like to work there. On the left in the above photo you can see a bunch of disarticulated Allosaurus bones suspended above the floor on wires. These are placed to give an idea of the three-dimensional jumbling of the bones in the matrix. It is almost impossible to jacket one bone or even several without hitting others. I remember how that goes from working at the OMNH sauropod bonebed in the Cloverly–it’s almost impossible to avoid blowing through some bones just to get others out of the ground.

4 - Camarasaurus pelvis with bite marks

Here’s one of a handful of bones from the quarry with bite marks. This is the pelvis of a Camarasaurus, lying upside down, anterior toward the wall. The back end of the right ilium is heavily tooth-marked.

After Cleveland-Lloyd we stopped at a couple of sites in the Mussentuchit. I’m not going to blog about those because they are active sites that are still producing fossils. Unfortunately it is not uncommon for fossil localities on public land to be looted and vandalized by unscrupulous private collectors. I don’t want to give those a-holes any help, so I’ve deliberately not shown any photos of about half a dozen of the most interesting sites that we visited during the conference. It sucks to know cool things and not be able to tell people about them, but if I blab then I put those cool things at risk. Happily there is a lot of active research going on, including one or two projects that got hatched at this conference, so hopefully I will be able to tell some of these stories soon.

5 - MMFC14 conveners Jim Rebecca and John

Instead, I will close this series (for now) with a shout-out to the people who convened and ran the field conference: Jim Kirkland (left) and ReBecca Hunt-Foster (middle). John Foster (right) also contributed a lot of time, energy, effort, and expertise.

Jim Kirkland is amazing. If you know him, you know that his heart is as big and outgoing as his booming voice. His knowledge of and enthusiasm for the mid-Mesozoic sites in western Colorado and eastern Utah have driven a lot of science over the past quarter century, and he shared that knowledge and enthusiasm compulsively on this trip. My head is so full of new stuff, it’s honestly hard to think. I wish I had a solid week to just digest everything I learned at the conference.

My highest praise and thanks go to ReBecca. Thanks to her hard work and organization, the whole field conference ran about as much like clockwork as something this complicated can–and when it didn’t run smoothly, like that flat tire on Saturday, she took charge and got us back on track. She was basically den mom to about 60 folks, from teenagers to retirees, from at least ten countries and four continents, and somehow she did it all with unflagging grace and good humor. The fact that she had her appendix out just two or three days before the start of the conference only cements my admiration for what she pulled off here.

I had a fantastic time. I hope they do another one.

Actually we had the Jurassic talks today, but I can’t show you any of the slides*, so instead you’re getting some brief, sauropod-centric highlighs from the museum.

* I had originally written that the technical content of the talks is embargoed, but that’s not true–as ReBecca Hunt-Foster pointed out in a comment, the conference guidebook with all of the abstracts is freely available online here.

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Like this Camarasaurus that greets visitors at the entrance.

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And this Apatosaurus ilium with bite marks on the distal end, indicating that a big Morrison theropod literally ate the butt of this dead apatosaur. Gnaw, dude, just gnaw.

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And the shrine to Elmer S. Riggs.

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One of Elmer’s field assistants apparently napping next to the humerus of the Brachiosaurus alithorax holotype. This may be the earliest photographic evidence of someone “pulling a Jensen“.

Cary and Matt with Brachiosaurus forelimb

Here’s the reconstructed forelimb of B. altithorax, with Cary Woodruff and me for scale. The humerus and coracoid (and maybe the sternal?) are cast from the B.a. holotype, the rest of the bits are either sculpted or filled in from Giraffatitan. The scap is very obviously Giraffatitan.

Matt with MWC Apatosaurus femur

Cary took this photo of me playing with a fiberglass 100% original bone Apatosaurus femur upstairs in the museum office, and he totally passed up the opportunity to push me down the stairs afterward. I kid, I kid–actually Cary and I get along just fine. It’s no secret that we disagree about some things, but we do so respectfully. Each of us expects to be vindicated by better data in the future, but there’s no reason we can’t hang out and jaw about sauropods in the meantime.

Finally, in the museum gift shop (which is quite lovely), I found this:

Dammit Nova

You had one job, Nova. ONE JOB!

So, this is a grossly inadequate post that barely scratches the surface of the flarkjillion or so cool exhibits at the museum. I only got about halfway through the sauropods, fer cryin’ out loud. If you ever get a chance to come, do it–you won’t be disappointed.

You know the drill: lotsa pretty pix, not much yap.

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Our first stop of the day was the Fruita Paleontological Area, which has a fanstastic diversity of Morrison animals, including the mammal Fruitafossor and the tiny ornithopod Fruitadens.

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Plus it’s a pretty epic landscape, especially with the clouds and broken light we had this morning.

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I found a bone! Several bits, actually, a few meters away from the Fruitadens type quarry. I’d like to think that this proximal femur might be Fruitadens, but I don’t know the diagnostic characters and haven’t had time to look them up. Anyone know how diagnostic this honorary shard of excellence might be?

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After lunch, John Foster took us on a short hike to the quarry where Elmer Riggs got the back half of the Field Museum Apatosaurus. The front half came from a site in southern Utah, several decades later.

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The locals brought Riggs out in the 1930s for the dedication of two monuments–this one at the Apatosaurus quarry, and another like it at the Brachiosaurus quarry some miles away. Tragically, both monuments have the names of the dinosaurs misspelled!

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In the afternoon we visited the Mygatt-Moore Quarry and the Camarasaurus site in Rabbit Valley. Can you see the articulated Camarasaurus neck in this photo?

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Here’s a hint: the neural arches of two posterior cervical vertebrae in transverse horizontal cross-section.

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This Camarasaurus is apparently a permanent feature. If you’re wondering why no-one has excavated it, it’s because it’s buried in sandstone that is stupid-dense. The expenditure of time and resources just isn’t worth it, when right down the hill dinosaurs are pouring out of the much softer sediments of the Mygatt-Moore Quarry like water from a hydrant. This is the lesson I am learning about the Morrison: finding dinosaurs is easy. Finding dinosaurs you can get out of the ground and prepare–that’s something else.

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Our last stop of the day was Gaston Design, where Rob Gaston showed us how he molds, casts, and mounts everything from tiny teeth to good-sized skeletons.

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Like this Deinosuchus that is about to chomp on Jim Kirkland. Jim doesn’t look too worried.

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Here’s a nice cast of a busted sauropod dorsal, probably from Apatosaurus or Diplodocus, showing the pneumatic internal structure. Compare to similar views of dorsals in this post and this one. This is actually one half of a matched set that includes both halves of the centrum. I left with one of those sets of my own, a few dollars poorer and a whole lot happier.

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The end–for now.

Illustration talk slide 39

Illustration talk slide 40

Illustration talk slide 41

Illustration talk slide 42

Illustration talk slide 43

The Sauroposeidon stuff is cribbed from this post. For the pros and cons of scale bars in figures, see the comment thread after this post. MYDD is, of course, a thing now.

Previous posts in this series.

Reference:

Wedel, M.J., and Taylor, M.P. 2013. Neural spine bifurcation in sauropod dinosaurs of the Morrison Formation: ontogenetic and phylogenetic implications. Palarch’s Journal of Vertebrate Palaeontology 10(1): 1-34. ISSN 1567-2158.

Last time, we took a very quick look at YPM 1910, a mounted skeleton that is the holotype of Camarasaurus (= “Morosaurus“) lentus, in the dinosaur hall of the Yale Peabody Museum.

Here’s the whole skeleton, in various views. Skip down to the bottom for the science; or just enjoy the derpiness. First, in anterior view:

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Here’s a more informative right anterolateral view. As you can see, this little Camarasaurus is in every sense in the shadow of the the much more impressive Apatosaurus (= “Brontosaurus“) excelsus holotype, YPM 1980: click through for the full image:

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And here’s the corresponding photo from Lull (1930: figure 1) (see below):

Camarasaurus lentus, holotype skeleton, oblique front view (Full 1930: fig. 1)

Camarasaurus lentus, holotype skeleton, oblique front view (Lull 1930: fig. 1)

It’s interesting to see such a familiar mount in such unfamiliar surroundings. Judging by the cabinets in the background, YPM 1910 was mounted in what’s now the dinosaur hall at Yale — i.e. it hasn’t moved since the photo was taken. But back then, Brontosaurus hadn’t been mounted, and Zallinger’s mural hadn’t been painted.

If you thought this animal looked dumb from the front, check out this left anterodorsolateral view, taken from the balcony above the hall. The foreshortening of the neck makes Cam look like a particularly dense puppy.

(Once more, click through for the full version of the photo, including the much more impressive Apatosaurus.)

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Right lateral view, with Zallinger’s justly famous mural in the background. Note the Diplodocus-type double-beamed chevrons in the tail:

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Here’s the justly under-rated posterior view:

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And finally, Lull’s left posterolateral photo — taken from a position that can’t now be replicated, due to the inconveniently located Brontosaurus. (The Archelon in the background, which was previously featured on SV-POW!, has been moved to the end of the hall since Lull’s time.

Camarasaurus lentus, oblique rear view. Lull (1930: fig. 2)

Camarasaurus lentus, oblique rear view. Lull (1930: fig. 2)

How much of this skeleton is real? Happily, not the skull. We can only hope that the real thing wasn’t quite so troubling. But much of the rest of the skeleton is real bone. To quote Lull (1930:1-3):

In the Yale specimen the entire vertebral column is present from the second or third cervical to the tenth caudal with one or two later caudals. Of the limbs and their girdles there are present the left scapula, right coracoid, both humeri, the left radius and ulna, both ilia, the right pubis and left ischium, and both femora, tibiae and fibulae. One cervical rib is present but no thoracic ribs. The disarticulated sacrum lacked one rib from either side.

(How could Lull have been unsure whether the most anterior preserved cervical was the second or third? C2 in sauropods, as in most animals, is radically different from the subsequent cervicals. He does go on to say that only the centrum of the most anterior vertebra is preserved, but the axis has a distinct anterior central articulation.)

Lull is quite ready to criticise the mount, and notes in particular:

The cervical ribs in the Yale mount are not long enough by half, and the thoracic ribs may be somewhat heavy and their length a little short [...] both carpus and tarsus are probably incorrect, as the elements in each instance are fewer than shown, there being no more than two at most. There is apparently no justification for the fore and aft extensions of the distal chevrons, as these were not preserved and the Osborn-Mook restoration was followed. [...] A probable error lies in too great an allowance for cartilage between the [pelvic] elements, thus making the acetabulum seem rather large.

He also notes a scheme that sadly never came to pass:

[The holotype of Camarasaurus (= "Morosaurus") robustus], a very perfect specimen, we intend to mount when the great Brontosaurus excelsus type is completed. The three sauropods, ranging in length from 21 to nearly 70 feet, should make a very impressive group.

They would have done! But in the end it fell to the Museum für Naturkunde Berlin to give us the world’s first three-sauropod combo (unless someone knows of an earlier one?)

Finally; the mounted Yale Camarasaurus also crops up in three of the plates of Ostrom and McIntosh (1966). Plate 60 depicts metacarpals I and II in all the cardinal views except for some reason posterior; plate 61 does the same for metacarpals III and IV); and plate 70 shows the right pubis in every aspect but anterior. Here it is:

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Morosaurus lentus [Now referred to Camarasaurus lentus] Marsh (1889) YPM 1910 (holotype). Right pubis (reversed) in medial (1), posterior (2), lateral (3), proximal (4), and distal (5) views; transverse sections through blade (6) and shaft (7). (Ostrom and McIntosh 1966: plate 70)

Judging by this, it’s a beautifully preserved element with some very distinctive morphology. But we’ve been burned by Marsh’s plates before, and I don’t trust them at all any more — at least, not until I’ve seen the elements for myself. Now I wish I paid more attention to Derpy’s pubes.

And on that line, I’m out.

References

Lull, Richard S. 1930. Skeleton of Camarasaurus lentus recently mounted at Yale. American Journal of Science, 5th series, 19(109):1-5.

Ostrom, John H., and John S. McIntosh. 1966. Marsh’s Dinosaurs: the Collections from Como Bluff. Yale University Press, New Haven, CT. 388 pages including 65 positively scrumptious plates.

Matt’s harsh-but-fair “Derp dah durr” / “Ah hurr hurr hurr” captions on his Giraffatitan skull photos reminded me that there is a sauropod with a much, much stupider head than that of Giraffatitan. Step forward YPM 1910, a mounted skeleton that is the holotype of Camarasaurus (= “Morosaurus“) lentus, in the dinosaur hall of the Yale Peabody Museum.

Herp derp derp

Full details on this specimen next time!

(But a spoiler: the skull isn’t real.)

We jumped the gun a bit in asking How fat was Camarasaurus? a couple of years ago, or indeed How fat was Brontosaurus? last year. As always, we should have started with extant taxa, to get a sense of how to relate bones to live animals — as we did with neck posture.

So here we go. I give you a herd of Indian elephants, Elephas maximus (from here):

056-Elephant-c-Gehan-de-Silva-Wijeyeratne-Minneriya-2004-07-27-165-Gathering

You will notice, from this conveniently-close-to-anterior view, that their torsos bulge out sideways, much further than the limbs.

Now let’s take a look at the skeleton of the same animal in the Oxford University Museum of Natural History (downloaded from here but for some reason the photo has now gone away):

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The rib-cage is tiny. It doesn’t even extend as far laterally as the position of the limb bones.

(And lest you think this is an oddity, do go and look at any mounted elephant skeleton of your choice, Indian or African. They’re all like this.)

What’s going on here?

Is Oxford’s elephant skeleton mounted incorrectly? More to the point, are all museums mounting their elephants incorrectly? Do elephants’ ribs project much more laterally in life?

Do elephants have a lot of body mass superficial to the rib-cage? If so, what is that mass? It’s hard to imagine they need a huge amount of muscle mass there, and it can’t be guts. Photos like this one, from the RVC’s televised elephant dissection on Inside Nature’s Giants, suggest the ribs are very close to the body surface:

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I’m really not sure how to account for the discrepancy.

Were sauropods similarly much fatter than their mounted skeletons suggest? Either because we’re mounting their skeletons wrongly with the ribs too vertical, or because they had a lot of superficial body mass?

Consider this mounted Camarasaurus skeleton in the Dinosaur Hall at the Arizona Museum of Natural History (photo by N. Neenan Photography, CC-BY-SA):

Camarasaurus_skeleton

Compare the breadth of its ribcage with that of the elephant above, and then think about how much body bulk should be added.

This should encourage palaeoartists involved in the All Yesterdays movement to dramatically bulk up at least some of their sauropod restorations.

It should also make us think twice about our mass estimates.

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