April 27, 2015
A couple of weekends ago, London and I went camping and stargazing at Afton Canyon, a nice dark spot about 40 miles east of Barstow. On the way home, we took the exit off I-15 at Ghost Town Road, initially because we wanted to visit the old Calico Ghost Town. But then we saw big metal dinosaurs south of the highway, and that’s how we came to Peggy Sue’s Diner and in particular the Diner-saur Park.
The Diner-saur Park is out behind the diner and admission is free. There are pools with red-eared sliders, paved walkways, grass, trees, a small gift shop, and dinosaurs. Here’s a Spinosaurus – curiously popular in the Mojave Desert, those spinosaurs.
Ornithischians are represented by two stegosaurs, this big metal one and a smaller concrete one under a tree.
The turtles are entertaining. They paddle around placidly and crawl out to bask on the banks of the pools, and on little islands in the centers.
The gift shop is tiny and the selection of paleo paraphernalia is not going to blow away any hard-core dinophiles. But it is not without its charm. And, hey, when you find a dinosaur gift shop in the middle of nowhere, you don’t quibble about size. London got some little plastic turtles and I got some cheap and horribly inaccurate plastic dinosaur skeletons to make a NecroDinoMechaLaser Squad for our Dinosaur Island D&D campaign.
Now, about that sauropod. The identification sign on the side of the gift shop notwithstanding, this is not a Brachiosaurus. With the short forelimbs and big back end, this is clearly a diplodocid. The neck is too skinny for Apatosaurus or the newly-resurrected Brontosaurus, and too long for Diplodocus. I lean toward Barosaurus, although I noticed in going back through these photos that with the mostly-straight, roughly-45-degree-angle neck, it is doing a good impression of the Supersaurus from my 2012 dinosaur nerve paper. Compare this:
If I had noticed it sooner, I would have maneuvered for a better, more comparable shot.
Guess I’ll just have to go back.
This was inspired by an email Mike sent a couple of days ago:
Remind yourself of the awesomeness of Giraffatitan:
Now think of this. Its neck is 8.5m long. Knock of one measly meter — for example, by removing one vertebra from the middle of the neck — and you have 7.5 m.
Supersaurus’s neck was probably TWICE that long.
I replied that I was indeed freaked out, and that it had given me an idea for a post, which you are now reading. I didn’t have a Giraffatitan that was sufficiently distortion-free, so I used my old trusty Brachiosaurus. The vertebra you see there next to Mike and next to the neck of Brachiosaurus is BYU 9024, the longest vertebra that has ever been found from anything, ever.
Regarding the neck length of Supersaurus, and how BYU 9024 came to be referred to Supersaurus, here’s the relevant chunk of my dissertation (Wedel 2007: pp. 208-209):
Supersaurus is without question the longest-necked animal with preserved cervical material. Jim Jensen recovered a single cervical vertebra of Supersaurus from Dry Mesa Quarry in western Colorado. The vertebra, BYU 9024, was originally referred to “Ultrasauros”. Later, both the cervical and the holotype dorsal of “Ultrasauros” were shown to belong to a diplodocid, and they were separately referred to Supersaurus by Jensen (1987) and Curtice et al. (1996), respectively.
BYU 9024 has a centrum length of 1378 mm, and a functional length of 1203 mm (Figure 4-3). At 1400 mm, the longest vertebra of Sauroposeidon is marginally longer in total length [see this post for a visual comparison]. However, that length includes the prezygapophyses, which overhang the condyle, and which are missing from BYU 9024. The centrum length of the largest Sauroposeidon vertebra is about 1250 mm, and the functional length is 1190 mm. BYU 9024 therefore has the largest centrum length and functional length of any vertebra that has ever been discovered for any animal. Furthermore, the Supersaurus vertebra is much larger than the Sauroposeidon vertebrae in diameter, and it is a much more massive element overall.
Neck length estimates for Supersaurus vary depending on the taxon chosen for comparison and the serial position assumed for BYU 9024. The vertebra shares many similarities with Barosaurus that are not found in other diplodocines, including a proportionally long centrum, dual posterior centrodiapophyseal laminae, a low neural spine, and ventrolateral flanges that connect to the parapophyses (and thus might be considered posterior centroparapophyseal laminae, similar to those of Sauroposeidon). The neural spine of BYU 9024 is very low and only very slightly bifurcated at its apex. In these characters, it is most similar to C9 of Barosaurus. However, theproportions of the centrum of BYU 9024 are more similar to those of C14 of Barosaurus, which is the longest vertebra of the neck in AMNH 6341. BYU 9024 is 1.6 times as long as C14 of AMNH 6341 and 1.9 times as long as C9. If it was built like that of Barosaurus, the neck of Supersaurus was at least 13.7 meters (44.8 feet) long, and may have been as long as 16.2 meters (53.2 feet).
Based on new material from Wyoming, Lovelace et al. (2005 [published as Lovelace et al. 2008]) noted potential synapomorphies shared by Supersaurus and Apatosaurus. BYU 9024 does not closely resemble any of the cervical vertebrae of Apatosaurus. Instead of trying to assign its serial position based on morphology, I conservatively assume that it is the longest vertebra in the series if it is from an Apatosaurus-like neck. At 2.7 times longer than C11 of CM 3018, BYU 9024 implies an Apatosaurus-like neck about 13.3 meters
(43.6 feet) long.
Bonus comparo: BYU 9024 vs USNM 10865, the mounted Diplodocus longus at the Smithsonian, modified from Gilmore 1932 (plate 6). For this I scaled BYU 9024 against the 1.6-meter femur of this specimen.
If you’d like to gaze upon BYU 9024 without distraction, or put it into a composite of your own, here you go:
- Gilmore, C. W. 1932. On a newly mounted skeleton of Diplodocus in the United States National Museum. Proceedings of the United States National Museum 81, 1-21.
- Lovelace, David M., Scott A. Hartman and William R. Wahl. 2008. Morphology of a specimen of Supersaurus (Dinosauria, Sauropoda) from the Morrison Formation of Wyoming, and a re-evaluation of diplodocid phylogeny. Arquivos do Museu Nacional, Rio de Janeiro, 65 (4): 527-544.
- Wedel, M.J. 2007. Postcranial pneumaticity in dinosaurs and the origin of the avian lung. PhD dissertation, University of California, Berkeley, Department of Integrative Biology, 303 pp.
May 19, 2014
Now considered a junior synonym of Supersaurus, on very solid grounds.
Incidentally, unlike the neural spines of most non-titanosaurian sauropods, the neural spine of this vertebra is not simply a set of intersecting plates of bone. It is hollow and has a central chamber, presumably pneumatic. Evidence:
I need to be sleeping, not blogging, so here are just the highlights, with no touch-ups and minimal commentary.
I don’t know what these real street signs were doing sitting on the ground when I walked to the museum this morning, but it was a good omen for the conference.
Home base for this part of the conference. We head to Green River, Utah, on Friday for the Early Cretaceous half.
I had never seen this on exhibit. This is not the Brachiosaurus scapulocoracoid formerly referred to “Ultrasauros”, this is the other big scap from Dry Mesa, from the giant diplodocid Supersaurus.
This is not Dinosaur Baptist Church–it is a cathedral of an entirely different order.
And that order is Sauropoda.
The sauropod bones are entombed in a matrix consisting of super-hard sandstone and non-sauropod bits.
I got about 150 photos of the Wall, but only because I ran out of time. You probably already know what I’m going to attempt with them. (If not, here’s a hint.)
Jim Kirkland (center left) literally walked us through the Morrison and Cedar Mountain Formations at this set of exposures north of the visitor center. The reddish stuff on the lower left is Morrison, and after that it’s CMF all the way up this ridge and next two behind it.
A cast of Diplodocus carnegii at the Utah Field House of Natural History State Park Museum, signalling that we’ve come to end of this tail–er, tale.
Further updates as time and opportunity allow. If you tweet about the conference, please use #MMFC14!
March 15, 2013
Today sees the publication of my big paper with Mike on neural spine bifurcation, which has been in the works since last April. It’s a free download here, and as usual we put the hi-res figures and other supporting info on a sidebar page.
Navel-gazing about the publication process
This paper is a departure for us, for several reasons.
For one thing, it’s a beast: a little over 13,000 words, not counting tables, figure captions, and the bibliography. I was all geared up to talk about how it’s my longest paper after the second Sauroposeidon paper (Wedel et al. 2000), but that’s not true. It’s my longest paper, period (13192 vs 12526 words), and the one with the most figures (25 vs 22).
It’s the first time we’ve written the paper in the open, on the blog, and then repackaged it for submission to a journal. I have several things to say about that. First, it was more work than I expected. It turns out that I definitely do have at least two “voices” as a writer, and the informal voice I used for the initial run of blog posts (linked here) was not going to cut it for formal publication. So although there is very little new material in the paper that was not in the blog posts, a lot of the prose is new because I had to rewrite almost the whole thing.
I have mixed feelings about this. On one hand, last May kinda sucked, because just about every minute that wasn’t spent eclipse chasing was spent rewriting the paper. On the other hand, as Mike has repeatedly pointed out to me, it was a pretty fast way to generate a big paper quickly, even with the rewriting. It was just over two months from the first post in the destined-to-become-a-paper series on April 5, to submission on June 14 (not June 24 as it says on the last page of the PDF), and if you leave out the 10 days in late May that I was galavanting around Arizona, the actual time spent working on the paper was a bit under two months. It would be nice to be that productive all the time (it helped that we were basically mining everything from previously published work; truly novel work usually needs more time to get up and going).
You may fairly wonder why, if almost all the content was already available on the blog, we went to the trouble of publishing it in a journal. Especially in light of sentiments like this. For my part, it’s down to two things. First, to paraphrase C.S. Lewis, what I wrote in that post was a yell, not a thought. I never intended to stop publishing in journals, I was just frustrated that traditional journals do so many stupid things that actually hurt science, like rejecting papers because of anticipated sexiness or for other BS reasons, not publishing peer reviews, etc. Happily, now there are better options.
Second, although in a sane world the quality of an argument or hypothesis would matter more than its mode of distribution, that’s not the world we live in. We’re happy enough to cite blog posts, etc. (they’re better than pers. comms., at least), but not everyone is, and the minimum bound of What Counts is controlled by people at the other end of the Overton window. So, bottom line, people are at least theoretically free to ignore stuff that is only published on blogs or other informal venues (DML, forums, etc.). If you want to force someone to engage with your ideas, you have to publish them in journals (for now). So we did.
Finally, ever since Darren’s azhdarchids-were-storks post got turned into a paper, it has bothered me that there is an icon for “Blogging on Peer-Reviewed Research” (from ResearchBlogging.org), but not one (that I know of) for “Blogging Into Peer-Reviewed Research”. If you have some graphic design chops and 10 minutes to kill, you could do the world a favor by creating one.
Hey, you! Want a project?
One of the few things in the paper that is not in any of the blog posts is the table summarizing the skeletal fusions in a bunch of famous sauropod specimens, to show how little consistency there is:
(Yes, we know that table legends typically go above, not below; this is just how they roll at PJVP.)
I want this to not get overlooked just because it’s in a long paper on neural spine bifurcation; as far as I’m concerned, it’s the most important part of the paper. I didn’t know that these potential ontogenetic indicators were all mutually contradictory across taxa before I started this project. Not only is the order of skeletal fusions inconsistent among taxa, but it might also be inconsistent among individuals or populations, or at least that’s what the variation among the different specimens of Apatosaurus suggests.
This problem cries out for more attention. As we say at the end of the paper:
To some extent the field of sauropod paleobiology suffers from ‘monograph tunnel vision’, in which our knowledge of most taxa is derived from a handful of specimens described decades ago (e.g. Diplodocus carnegii CM 84/94). Recent work by McIntosh (2005), Upchurch et al. (2005), and Harris (2006a, b, c, 2007) is a welcome antidote to this malady, but several of the taxa discussed herein are represented by many more specimens that have not been adequately described or assessed. A comprehensive program to document skeletal fusions and body size in all known specimens of, say, Camarasaurus, or Diplodocus, could be undertaken for relatively little cost (other than travel expenses, and even these could be offset through collaboration) and would add immeasurably to our knowledge of sauropod ontogeny.
So if you’re looking for a project on sauropod paleobiology and you can get around to a bunch of museums*, here’s work that needs doing. Also, you’ll probably make lots of other publishable observations along the way.
* The more the better, but for Morrison taxa I would say minimally: Yale, AMNH, Carnegie, Cleveland Museum of Natural History, Field Museum, Dinosaur National Monument, BYU, University of Utah, and University of Wyoming, plus Smithsonian, University of Kansas, OMNH, Denver Museum, Wyoming Dinosaur Center, and a few others if you can swing it. Oh, and Diplodocus hayi down in Houston. Check John Foster’s and Jack McIntosh’s publications for lists of specimens–there are a LOT more out there than most people are familiar with.
- Wedel, M.J., R.L. Cifelli and R.K. Sanders. 2000. Osteology, paleobiology, and relationships of the sauropod dinosaur Sauroposeidon. Acta Palaeontologica Polonica 45(4): 343-388.
- 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.
March 13, 2013
At the top: our old friend BYU 9024 — the cervical vertebra that’s part of the Supersaurus vivianae holotype. At the bottom, C2 (the longest cervical) of Giraffa camelopardalis angolensis FMNH 34426.
The Supersaurus vertebra is 138 cm long. We don’t know which cervical it is, but there’s no reason to think it’s the longest. The giraffe vertebra is 31 cm long. Not only is the Supersaurus vertebra four times as long as that of the giraffe, it’s one of more than twice as many cervicals as the giraffe has.
Did we cheat by using an unusually small giraffe? Not really. When we articulated all seven cervicals as best we could, the sequence measured 171 cm, which is a fairly healthy 71% of the 2.4 m neck of the world-record giraffe. It’s not a monster, but it’s a decent-sized adult.
Bottom line, giraffes are just lame.
February 17, 2013
If you found the hypothetical Amphicoelias fragillimus cervical in a recent post a bit too much to swallow, I won’t blame you. But how big do we know Morrison diplodocoid cervicals got?
The longest centrum of any specimen of anything, anywhere, is that of the cervical vertebra BYU 9024 that’s part of the Supersaurus vivianae holotype. It’s 138 cm long, which means that composited at scale with an MTSRSU, it looks like this:
This is not hypothetical. It’s an actual fossil.