Omeisaurus is Just Plain Wrong
August 28, 2008
When we were planning to start this blog, Matt wrote to Darren and me saying “I am thinking that we should keep the text short and sweet” — an aspiration that we have consistently failed to live up to. Not today!
Here is Omeisaurus tianfuensis. Even by sauropod standards, that neck is just plain crazy.
This figure is lifted from an awesomely comprehensive monograph — 173 pages including the front-matter and plates — which gives the lie to the idea that all Chinese dinosaurs are woefully inadequately described. It’s true that with the recent glut of theropods, the thing seems to be to rip ’em out of the ground, throw toegther a two-pager for Science or Nature and move on to the next one; but sauropods understandably inspire more devotion from their followers, resulting in careful work like this monograph and the similar work by Ouyang and Ye (2002) on Mamenchisaurus youngi. So hats off to He, Ouyang and their colleagues — showing how it should be done!
Special bonus photo
References
- He, X., K. Li, and K. Cai. 1988. The Middle Jurassic dinosaur fauna from Dashanpu, Zigong, Sichuan, vol. IV: sauropod dinosaurs (2): Omeisaurus tianfuensis. Sichuan Publishing House of Science and Technology, Chengdu, China. 143 + 20 plates pp.
- Ouyang, H., and Y. Ye. 2002. The first mamenchisaurian skeleton with complete skull: Mamenchisaurus youngi. Sichuan Science and Technology Press, Chengdu, China. 111 + 20 plates pp.
SV-POW! on tour: Oxford University Museum of Natural History
August 21, 2008
It’s very rare that all three of us SV-POW!ers get together: in fact, until Tuesday this week, it had only ever happened once, at SVPCA 2005. But as Matt was spending nearly a fortnight with me (Mike) in England, far from his native land — an unholy blend of Oklahoma and California — it would have been stupid not to have all got together. So we did, on the 19th, at the Oxford University Museum of Natural History (OUMNH).
The public gallery of the OUMNH is my favourite in the whole world, despite its inexplicable failure to exhibit so much as a single sauropod presacral. That’s because it is just so darned full of stuff. For example, here is Darren, with me, trying to figure out how ventral compressing-bracing of the neck is supposed to work in crocodiles:
Above our heads is a sequence of whale skeletons; to the right is a cabinet full of stuffed crocodilians; in the background, poking its head over the cabinet is a cast of the T. rex “Stan”. Further cabinets in the isle we’re in contain turtles, bizarre fish skulls, giant frog skeletons, and much, much more. Turn a corner and you’re confronted by a vampire squid; face the other direction and there’s a giant Japanese spider crab, or an absurdly oversized pliosaur mandible, or a cast of a Bernissart Iguanodon, or the skeleton of an echidna, giraffe or juvenile gorilla — or any one of a hundred thousand other fascinating exhibits. What you won’t find is “interactives” (i.e. the low-rent video games that infest nearly all museums and which are embarrasingly lame compared with what the kids can play at home on their X-boxes.)
Does this mean that the museum has made itself interesting for clever, sophisticated adults at the cost of being too “difficult” for children? Not a bit of it: Fiona and I took our three sons to the OUMNH a couple of months ago, and I have literally never seen them so excited about anything. Ever. All three of them were running from exhibit to exhibit for two solid hours, constantly calling each other and us to Wow! Come and see THIS! Guess what? Turns out that, when people go to Natural History museums, they like to look at Natural History. So OUMNH is a salutory lesson to every museum whose public galleries have been ruined by people who have, somehow, failed to understand this very, very, very simple principle.
Anyway, sorry for the tangent. What I wanted to show you was The Three SV-POW!sketeers, together at last! So here we are, in front of a bunch of awesome artiodactyl skeletons. From left to right, Mike, Matt and Darren.
(In case you’re wondering, those four grey blobs on my T-shirt are dorsals 8 and 9 from Migeod’s Tendaguru brachiosaurid, BMNH R5937, in posterior, right lateral and anterior views. One of these days, I’ll show you those properly.)
Anyway: packed though the museum is with wonderful things, there is one particular exhibit that stands head and shoulders above every other — a specimen so literally awe-inspiring that, wherever you are in the museum, whatever you’re looking at, you can hardly help but be aware of it, lurking in your peripheral vision and ready to command your full attention. We’re talking about a dinosaur so iconic that it needs no introduction: so, here we are, studying an anterior caudal vertebra of Cetiosaurus oxoniensis:
And finally, here we are having torn ourselves away from the Caudal Of Awesomeness, facing the camera for your pleasure:
That’s all for today — hope you can forgive the “lite” nature of this week’s post: we’ll get back to your usual hardcore action real soon now (though possibly not before a few more OUMNH pictures).
And, yes, we did also visit the collections at OUMNH; and, yes, we did find something absolutely fascinating. But we won’t be saying much about that on here, because we want to Wait For The Paper.
Bonus post: Sauroposeidon illustrated
August 14, 2008
Since my last post was rather heavier on the sushi than on the sauropod vertebrae, I offer this special bonus post. One of the frustrating things about the otherwise marvelous Sauroposeidon monograph (Wedel et al. 2000b) is that the figures are so small. Sadly this is also true of all the other publications that illustrate its remains, and so the published literature has no nice, detailed images.
No longer! I’ve scored a rare paper copy of Matt’s undergraduate thesis (Wedel 1997) which contained basically all the material that eventually became that monograph, and which in addition has much larger versions of the figures. So without further ado, I give you figure 5 of that paper:
Part A is similar to Wedel et al. (2000b:fig 6), and part B to Wedel et al. (2000b:fig. 7A), but this older version is rather nicer, and from a waaay better scan than is available for Wedel et al. (2000b).
And that’s all I have to say about that.
References.
- Wedel, Mathew J. 1997. A new sauropod from the Early Cretaceous of Oklahoma. Unpublished undergraduate thesis, University of Oklahoma, Norman, OK. 43 pages.
- Wedel, M.J., Cifelli, R.L., and Sanders, R.K. 2000b. Osteology, paleobiology, and relationships of the sauropod dinosaur Sauroposeidon. Acta Palaeontologica Polonica 45(4):343-388
Tutorial 6: Air-space proportion in pneumatic sushi
August 12, 2008
Matt is staying here at Taylor Towers for a couple of weeks while his wife spends some quality time with some leprous human remains in Bradford (yes, really). Since both Matt and I are big fans of sushi, I took a stab at making some at home on Sunday night:
We noticed that the spring onion in one of the rolls had held its shape sufficiently well to preserve an air-space running along the length of the roll:

Fig. 2. Spring-onion california roll, cross-section in anterior view. A, photograph; B, interpretive drawing. Anatomical abbreviations: av, avocado; cs, crab-stick; pf, pneumatic foramen; pr, prawn.
Using the technique of Wedel (2005:212-213), we can calculate the air-space proportion of this roll (ASP) by dividing the area of the enclosed pneumatic space by total cross-section.
The simplest way to do this is to reduce the image to simple black-and-white with a grey background and count the pixels:

Fig. 4. Sushi roll depicted in figure 2, with solid material drawn in black and pneumatic space in white.
According to image-processing program, the full-sized version of this images has 21961 white pixels and 302993 black pixels, yielding an ASP of W/(W+B) = 21961/(21961+302993) = 0.067, or 6.7%. This is a very low value compared to most sauropod vertebrae: according to Wedel (2005:table 7.2), values are mostly in the range 50-70% — nearly ten times as pneumatic as this sushi roll — with Sauroposeidon reaching 89% in a cervical prezygapophyseal ramus.
References
A new view of Brachiosaurus
August 6, 2008
Considering how much time I’ve spent playing around mounted sauropod skeletons, I cannot believe it never occurred to me to do this:
This is the mounted Brachiosaurus skeleton in the United terminal at Chicago O’Hare. It used to be in the main hall of the Field Museum, but they booted it out to make room for some vulgar overstudied theropod (ht to Paul Barrett for that supremely useful phrase). The indoor version was moved to O’Hare, and they made a second, weatherproof cast which is now mounted outside the northwest corner of the Field Museum.
We spend so much time looking at drawings or photos of bones or entire skeletons in lateral view. It is nice to get a kick-in-the-brainpan reminder that sauropods existed in 3D. And it is always rewarding to see something familiar from a new angle.
Lots of good stuff here. Anterior is toward the bottom of the photo; you can see the scapulae arcing back over the anterior ribs, the coracoids sternal plates converging and disappearing out of the bottom of the image, and the humeri angling out to either side. The thing does not really sprawl as much as it might seem from this picture–keep in mind that there is a lot of vertical foreshortening going on. Speaking of, you can see the neck zooming off into space at the bottom center. At the top of the image you can see the sacrum and the preacetabular blades of the ilia flaring out to either side.
The seven posterior dorsals are cast from the holotype of Brachiosaurus altithorax, as are the sacrum, the first couple of caudals, one humerus, one ilium, and one femur. The rest of the mounted skeleton is either mirrored from available elements or subbed in from Brachiosaurus brancai.
I’m posting this because (a) it’s a really cool photo, and (b) it illustrates something peculiar, which is that the dorsal vertebrae of Brachiosaurus are oddly–one might even say freakishly–slender. This is true of both the B. altithorax and B. brancai dorsals. I was recently standing under yet another copy of this skeleton and someone I was with asked if those were even the right vertebrae, because even to non-specialists they look too small.
I WILL have more to say about that one of these days, but for now just dig the austere beauty.
Photo (c) Tristan Savatier – www.loupiote.com – Used by permission.