The other side of the other side of that one cool specimen
November 11, 2019
Way back in 2009–over a decade ago, now!–I blogged about the above photo, which I stole from this post by ReBecca Hunt-Foster. It’s a cut and polished chunk of a pneumatic sauropod vertebra in the collections at Dinosaur Journey in Fruita, Colorado.
This is the other side of that same cut; you’ll see that it looks like a mirror image of the cut at the top, but not quite a perfect mirror image, because some material was lost to the kerf of the saw and to subsequent polishing, and the bony septa changed a bit just in those few millimeters.
And this is the reverse face of the section shown above. As you can see, it is a LOT more complex. What’s going on here? This unpolished face must be getting close to either the condyle or the cotyle, where the simple I-beam or anchor-shaped configuration of the centrum breaks up into lots of smaller chambers (as described in this even older post). It’s crazy how fast that can happen–this shard of excellence is only about 4 or 5 cm thick, and in that short space it has gone from anchor to honeycomb. I think that’s amazing, and beautiful.
It’s probably Apatosaurus–way too complex to be Camarasaurus or Haplocanthosaurus, not complex enough to be Barosaurus, no reason to suspect Brachiosaurus, and although there is other stuff in the DJ collections, the vast majority of the sauropod material is Apatosaurus. So that’s my null hypothesis for the ID.
Oh, back in 2009 I was pretty sure these chunks were from a dorsal, because of the round ventral profile of the centrum. I’m no longer so certain, now that I know that the anchor-shaped sections are so close to the end of the centrum, because almost all vertebrae get round near the ends. That said, the anchor-shaped sections are anchor-shaped because the pneumatic foramina are open, and having foramina that open, that close to the end of the vertebra still makes me think it is more likely a dorsal than anything else. I’m just less certain than I used to be–and that has been the common theme in my personal development over the last decade.
The Day of the Dinosaur, and the legend of the regrown sauropod tail
October 17, 2019
Two professionals, hard at work.
After this year’s SVPCA, Vicki and London and I spent a few days with the Taylor family in the lovely village of Ruardean. It wasn’t all faffing about with the Iguanodon pelvis, the above photo notwithstanding. Mike and I had much to discuss after the conference, in particular what the next steps might be for the Supersaurus project. Mike has been tracking down early mentions of Supersaurus, and in particular trying to determine the point at which Jensen decided that it might be a diplodocid rather than a brachiosaurid. I recalled that Gerald Wood discussed Supersaurus in his wonderful 1982 book, The Guinness Book of Animal Facts and Feats. While on the track of Supersaurus, I stumbled across this amazing claim in the section on Diplodocus (Wood 1982: p. 209):
According to De Camp and De Camp (1968) these giant sauropods may have been able to regenerate lost parts, and they mention another skeleton collected in Wyoming which appeared to have lost about 25 per cent of its tail to a carnosaur and then regrown it — along with 21 new vertebrae!
De Camp and De Camp (1968) is a popular or non-technical book, The Day of the Dinosaur. Used copies can be had for a song, so I ordered one online and it was waiting for me when I got back to California.
The Day of the Dinosaur is an interesting book. L. Sprague De Camp and Catherine Crook De Camp embodied the concept of the “life-long learner” before there was a buzzword to go with it. He had been an aerospace engineer in World War II, and she had been an honors graduate and teacher, before they turned to writing full time. Individually and together, they produced a wide range of science fiction, fantasy, and nonfiction books over careers that spanned almost six decades. The De Camps’ writing in The Day of the Dinosaur is erudite in range but conversational in style, and they clearly kept up with current discoveries. They also recognized that science is a human enterprise and that, like any exploratory process, it is marked by wildly successful leaps, frustrating wheel-spinning, and complete dead ends. I was pleasantly surprised to find that the authors were completely up to speed on plate tectonics, an essentially brand-new science in 1968, and they explain it as an alternative to older theories about immensely long land bridges or sunken continents.
At the same time, the book arrived just before the end-of-the-1960s publications of John Ostrom and Bob Bakker that kicked off the Dinosaur Renaissance, so there’s no mention of warm-blooded dinosaurs. The De Camps’ sauropods and duckbills are still swamp-bound morons, “endlessly dredging up mouthfuls of soft plant food and living out their long, slow, placid, brainless lives” (p. 142), stalked by ‘carnosaurs’ that were nothing more than collections of teeth relentlessly driven by blind instinct and hunger. The book is therefore an artifact of a precise time; there was perhaps a year at most in the late 1960s when authors as technically savvy as the De Camps would have felt obliged to explain plate tectonics and its nearly-complete takeover of structural geology (which had just happened), but not to comment on the new and outrageous hypothesis of warm-blooded, active, terrestrial dinosaurs (which hadn’t happened yet).
The book may also appeal to folks with an interest in mid-century paleo-art, as the illustrations are a glorious hodge-podge of Charles R. Knight, Neave Parker, photos of models and mounted skeletons from museums, life restorations reproduced from the technical literature, and original art produced for the book, including quite a few line drawings by one L. Sprague De Camp. Roy Krenkel even contributed an original piece, shown above (if you don’t know Krenkel, he was a contemporary and sometime collaborator of Al Williamson and Frank Frazetta, and his art collection Swordsmen and Saurians is stunning and still gettable at not-completely-ruinous prices; I’ve had mine since about 1997).
ANYWAY, as entertaining as The Day of the Dinosaur is, it doesn’t do much to help us regenerate the tale of the regenerated tail. Here’s the entire story, from page 114:
Sauropods, some students think, had great powers of regenerating lost parts. One specimen from Wyoming is thought to have lost the last quarter of its tail and regrown it, along with twenty-one new tail vertebrae. That is better than a modern lizard can do; for the lizard, in regenerating its tail, grows only a stumpy approximation of the original, without new vertebrae.
That’s it. No sources mentioned or cited, so no advance over Wood in terms of tracking down the origin of the story.
Massospondylus tail with traumatic amputation at caudal 25 (Butler et al. 2013: fig. 1A).
To be clear, I don’t really think there is a sauropod that regrew its tail, especially since we have evidence for traumatic tail amputation without regeneration in the basal sauropodomorph Massospondylus (Butler et al. 2013), in the theropod Majungasaurus (Farke and O’Connor 2007), and in a hadrosaur (Tanke and Rothschild 2002). But I would love to learn how such a story got started, what the evidence was, how it was communicated, and most importantly, how it took on a life of its own.
If anyone knows any more about this, I’d be very grateful for any pointers. The comment thread is open.
References
- Butler, R. J., Yates, A. M., Rauhut, O. W., & Foth, C. 2013. A pathological tail in a basal sauropodomorph dinosaur from South Africa: evidence of traumatic amputation? Journal of Vertebrate Paleontology 33(1): 224-228.
- De Camp, L. S., and De Camp, C. C. 1968. The Day of the Dinosaur. Bonanza Books, New York, 319 pp.
- Farke, A. A., & O’Connor, P. M. 2007. Pathology in Majungasaurus crenatissimus (Theropoda: Abelisauridae) from the Late Cretaceous of Madagascar. Journal of Vertebrate Paleontology, 27(S2): 180-184.
- Krenkel, R. G. 1989. Swordsmen and Saurians: From the Mesozoic to Barsoom. Eclipse Books, 152 pp.
- Tanke, D. H., & Rothschild, B. M. 2002. DINOSORES: An annotated bibliography of dinosaur paleopathology and related topics—1838-2001. Bulletin of the New Mexico Museum of Natural History and Science, vol. 20.
- Wood, G. L. 1982. The Guinness Book of Animals Facts & Feats (3rd edition). Guinness Superlatives Ltd., Enfield, Middlesex, 252 pp.
Walking around the mounted skeleton of Apatosaurus louisae
March 22, 2019
In case you haven’t gotten to do this, or need a refresher, or just want a little more Apatosaurus in your life. And honestly, who doesn’t? As with the previous Diplodocus walk-around, there’s no narration, just whatever ambient sound reached the mic. Go have fun.
How our week at the Carnegie Museum went
March 17, 2019
In a word, amazingly. After 6 days (counting public galleries last Sunday), 4300 photos, 55 videos, dozens of pages of notes, and hundreds of measurements, we’re tired, happy, and buzzing with new observations and ideas.
We caught up with some old friends. Here Mike is showing an entirely normal and healthy level of excitement about meeting CM 584, a specimen of Camarasaurus from Sheep Creek, Wyoming. You may recognize this view of these dorsals from Figure 9 in our 2013 PeerJ paper.
We spent an inordinate amount of time in the public galleries, checking out the mounted skeletons of Apatosaurus and Diplodocus (and Gilmore’s baby Cam, and the two tyrannosaurs, and, and…).
I had planned a trip to the Carnegie primarily to have another look at the Haplocanthosaurus holotypes, CM 572 and CM 879. I was also happy for the chance to photograph and measure these vertebrae, CM 36034, which I think have never been formally described or referred to Haplocanthosaurus. As far as I know, other than a brief mention in McIntosh (1981) they have not been published on at all. I’m planning on changing that in the near future, as part of the larger Haplocanthosaurus project that now bestrides my career like a colossus.
The real colossus of the trip was CM 555, which we’ve already blogged about a couple of times. Just laying out all of the vertebrae and logging serial changes was hugely useful.
Incidentally, in previous posts and some upcoming videos, we’ve referred to this specimen as Brontosaurus excelsus, because McIntosh (1981) said that it might belong to Apatosaurus excelsus. I was so busy measuring and photographing stuff that it wasn’t until Friday that I realized that McIntosh made that call because CM 555 is from the same locality as CM 563, now UWGM 15556, which was long thought to be Apatosaurus excelsus but which is now (i.e., Tschopp et al. 2015) referred to Brontosaurus parvus. So CM 555 is almost certainly B. parvus, not B. excelsus, and in comparing the specimen to Gilmore’s (1936) plates of CM 563, Mike and I thought they were a very good match.
Finding the tray of CM 555 cervical ribs was a huge moment. It added a ton of work to our to-do lists. First we had to match the ribs to their vertebrae. Most of them had field numbers, but some didn’t. Quite a few were broken and needed to be repaired – that’s what I’m doing in the above photo. Then they all had to be measured and photographed.
It’s amazing how useful it was to be able to reassociate the vertebrae with their ribs. We only did the full reassembly for c6, in part because it was the most complete and perfect of all of the vertebrae, and in part because we simply ran out of time. As Mike observed in his recent post, it was stunning how the apatosaurine identity of the specimen snapped into focus as soon as we could see a whole cervical vertebra put back together with all of its bits.
We also measured and photographed the limb bones, including the bite marks on the radius (above, in two pieces) and ulna (below, one piece). Those will of course go into the description.
And there WILL BE a description. We measured and photographed every element, shot video of many of them, and took pages and pages of notes. Describing even an incomplete sauropod skeleton is a big job, so don’t expect that paper this year, but it will be along in due course. CM 555 may not be the most complete Brontosaurus skeleton in the world, but our ambition is to make it the best-documented.
In the meantime, we hopefully left things better documented than they had been. All of the separate bits of the CM 555 vertebrae – the centra, arches, and cervicals ribs – now have the cervical numbers written on in archival ink (with permission from collections manager Amy Henrici, of course), so the next person to look at them can match them up with less faffing about.
We have people to thank. We had lunch almost every day at Sushi Fuku at 120 Oakland Avenue, just a couple of blocks down Forbes Avenue from the museum. We got to know the manager, Jeremy Gest, and his staff, who were unfailingly friendly and helpful, and who kept us running on top-notch food. So we kept going back. If you find yourself in Pittsburgh, check ’em out. Make time for a sandwich at Primanti Bros., too.
We owe a huge thanks to Calder Dudgeon, who took us up to the skylight catwalk to get the dorsal-view photos of the mounted skeletons (see this post), and especially to Dan Pickering, who moved pallets in collections using the forklift, and moved the lift around the mounted skeletons on Tuesday. Despite about a million ad hoc requests, he never lost patience with us, and in fact he found lots of little ways to help us get our observations and data faster and with less hassle.
Our biggest thanks go to collections manager Amy Henrici, who made the whole week just run smoothly for us. Whatever we needed, she’d find. If we needed something moved, or if we needed to get someplace, she’d figure out how to do it. She was always interested, always cheerful, always helpful. I usually can’t sustain that level of positivity for a whole day, much less a week. So thank you, Amy, sincerely. You have a world-class collection. We’re glad it’s in such good hands.
What’s next? We’ll be posting about stuff we saw and learned in the Carnegie Museum for a long time, probably. And we have manuscripts to get cranking on, some of which were already gestating and just needed the Carnegie visit to push to completion. As always, watch this space.
References
- McIntosh JS. 1981. Annotated catalogue of the dinosaurs (Reptilia, Archosauria) in the collections of Carnegie Museum of Natural History. Bulletin of Carnegie Museum of Natural History 18:1-67
- (2015) A specimen-level phylogenetic analysis and taxonomic revision of Diplodocidae (Dinosauria, Sauropoda) PeerJ3:e857 https://dx.doi.org/10.7717/peerj.857
Everything’s better with cervical ribs
March 15, 2019
You’ll remember that we’ve been playing with CM 555, a subadult apatosaurine of indeterminate species, though John McIntosh assigned it to Brontosaurus (then Apatosaurus) excelsus. At the start of the week, we had the centra and neural arches of cervicals 1-14, plus there were some appendicular elements on a shelf that we’d not yet gone to. But then today, Matt found this drawer:
It contained a nice selection of cervical ribs that were part of the same specimen. Jackpot!
[You might notice that some of them have the specimen number 584 written on them. The history is that CM 555 and CM 584 came out of the same quarry, but most of the bones were initially thought to belong to a camarasaur which was designated CM 584. John McIntosh (1981:25) identified them as belonging to an apatosaurine, and they are now considered to be part of CM 555. The limb bones are catalogued separately as CM 556, but recognised as likely belonging to the same individual.]
Most of these ribs had field numbers written on them which were able to use to associate them with individual cervicals; and those that lacked these numbers, we could associate anyway, because the options were limited to a relatively small number of gaps. The upshot is that we know which vertebra each of these belongs to.
We have both ribs of C6, which is probably the best preserved single vertebra — centrum and arch — so I was able to rebuild the vertebra from its component parts. Matt was impressed:
And to be fair, I was pretty darned impressed myself:
Truly, this is a beautiful specimen. It was already pretty lovely, but putting the cervical ribs in place changed everything. It was totally transformed from a nice diplodocid cervical to an absolutely rock-solid slam-dunk apatosaurine — one to make grown men weep.
Here it is in right posterolateral view, just generally being awesome.
References
- McIntosh, John S. 1981. Annotated catalogue of the dinosaurs (Reptilia, Archosauria) in the collections of Carnegie Museum of Natural History. Bulletin of the Carnegie Museum 18:1–67.
Mounted sauropods in dorsal view!
March 13, 2019
Mike’s and Matt’s excellent adventure in Pittsburgh continues! Today was Day 4, and just as yesterday offered us a unique opportunity to see the mounted Dipodocus and Apatosaurus skeletons up close on a lift, so today we got to look the two mounts from directly above!
Thanks to our host Amy Henrici and to Calder Dudgeon, we were able to go up to the maintenance balconies above the dinosaur hall, and from there we were able to see this:
It was a little bit scary up there: here’s Matt’s vertical panorama photo of me. Just below the balcony I’m standing on you can see another, which is actually far below up but further back. Below that is the main balcony that overlooks the hall. And below that, the hall itself, showing Diplodocus from above:
We think this is a first: we don’t know of any published photos of mounted sauropods from above — but now, there are some. Let’s take a closer look at the torsos:
Diplodocus carnegii holotype CM 84, torso, in dorsal view, anterior to right.
Apatosaurus louisae holotype CM 3018, torso, in dorsal view, anterior to left.
You can immediately see from here that Apatosaurus is a much broader animal than Diplodocus. That much, we could have guessed. What’s more interesting is that Apatosaurus seems to be slightly broader at the shoulders than at the hips, whereas the opposite is the case in Diplodocus.
This observation left us wondering what’s known about the relative widths of the forelimb and hindlimb articulations in extant animals. What, from the modern bestiary, has hips broader than its shoulders, and what has shoulders wider than its hips? We have no idea. Does anyone know if this has been studied, or better yet summarised?
