Sauroposeidon, the early years: my first drawing
February 7, 2018
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.
When I was nine, a copy of Don Glut’s The New Dinosaur Dictionary turned up in my local Waldenbooks. It wasn’t my first dinosaur book, by far – I’d been a dinosaurophile since the age of three. But The New Dinosaur Dictionary was different.
Up to that point, I had subsisted on a heavy diet of kids’ dino books and the occasional article in National Geographic and Ranger Rick. The kids’ books were aimed at kids and the magazine articles were pitched at an engagingly popular level. I didn’t understand every word, but they were clearly written for curious layfolk, not specialists.
A typical spread from The New Dinosaur Dictionary (Glut, 1982). The armored sauropod blew my young mind.
The New Dinosaur Dictionary was something else entirely. It had photos of actual dinosaur bones and illustrations of skeletons with cryptic captions like, “Skeleton of Daspletosaurus torosus. (After Russell)”. Okay, clearly this Russell cove was out there drawing dinosaur skeletons and this book had reproduced some of them. But nobody I knew talked like that, and the books I had access to up to that point held no comparable language.
The New Dinosaur Dictionary (Glut, 1982: p. 271)
Then there was stuff like this: “The so-called Von Hughenden sauropod restored as a brachiosaurid by Mark Hallett”. A chain of fascinating and pleasurable ideas detonated in my brain. “The so-called” – say what now? Nobody even knew what to call this thing? Somehow I had inadvertently sailed right to the edge of human knowledge of dinosaurs, and was peering out into taxa incognita. “Restored as a brachiosaurid” – so this was just one of several possible ways that the animal might have looked. Even the scientists weren’t sure. This was a far cry from the bland assurances and blithely patronizing tones of all my previous dinosaur books.
“By Mark Hallett.” I didn’t know who this Hallett guy was, but his art was all over the book, along with William Stout and some guy named Robert T. Bakker and a host of others who were exploding my conception of what paleo art could even be. Anyway, this Mark Hallett was someone to watch, not only because he got mentioned by name a lot, but because his art had a crisp quality that teetered on some hypercanny ridge between photorealism and scribbling. His sketches looked like they might just walk off the page.
In case that line about scribbling sounds dismissive: I have always preferred sketches by my favorite artists to their finished products. The polished works are frequently inhumanly good. They seem to have descended in a state of completed perfection from some divine realm, unattainable by mere mortals. Whereas sketches give us a look under the hood, and show how a good artist can conjure light, shadow, form, weight, and texture from a few pencil strokes. Put it this way: I am anatomist by temperament first, and by training and occupation second. Of course I want to see how things are put together.
The New Dinosaur Dictionary (Glut, 1982: p. 75)
Anyway, The New Dinosaur Dictionary was something completely new in my experience. It wasn’t aimed at kids and written as if by kids, like lots of kids’ books. It wasn’t even written by adults talking down (deliberately or inadvertently) to kids, or trying to reach a wide audience that might include kids. It was written by an adult, aiming at other adults. And it was admitting in plain language that we didn’t know everything yet, that there were lots of animals trembling on the outer threshold of scientific knowledge. I didn’t understand half of it – I was down in an ontogenetic trench, looking up as these packets of information exploded like fireworks over my head.
In Seeing In the Dark, the best book about why you should go out stargazing for yourself, Timothy Ferris writes about growing up on Florida’s Space Coast in the early 1960s, and watching the first generation of artificial satellites pass overhead:
I felt like an ancient lungfish contemplating the land from the sea. We could get up there.
That’s precisely the effect that The New Dinosaur Dictionary had on me: I could get up there. Maybe not immediately. But there were steps, bodies of knowledge that could be mastered piecemeal, and most of all, mysteries to be resolved. The book itself was like a sketch, showing how from isolated and broken bones and incomplete skeletons, scientists and artists reconstructed the world of the past, one hypothesis at a time. Now I take it for granted, because I’ve been behind the curtain for a couple of decades. But to my 9-year-old self, it was revolutionary.
This has all come roaring back because of something that came in the mail this week. Or rather, something that had been waiting in the mailroom for a while, that I finally picked up this week: a package from Mark Hallett, enclosing a copy of his 2018 dinosaur calendar. And also this:
An original sketch, which he gave to me as a Christmas present. The published version appears on one of the final pages of our book, where we discuss the boundaries between the known – the emerging synthesis of sauropod biology that we hoped to bring to a broader audience by writing the book in the first place – and the unknown – the enduring mysteries that Mark and I think will drive research in sauropod paleobiology for the next few decades. Presented without a caption or commentary, the sketch embodies sauropods as we see them: emerging from uncertainty and ignorance one hard-won line at a time, with ever-increasing solidity.
Thank you, Mark, sincerely. That sketch, what it evokes, both for me now and for my inner 9-year-old – you couldn’t have chosen a better gift. And I couldn’t be happier. Except perhaps to someday learn that our book exploded in the mind of a curious kid the way that The New Dinosaur Dictionary did for me 34 years ago, a time that now seems as distant and romantic as the primeval forests of the Mesozoic.
Paul Graham on blogging as a way to generate papers
January 16, 2018
Computer programmer, essayist and venture capitalist Paul Graham writes:
In most fields, prototypes have traditionally been made out of different materials. Typefaces to be cut in metal were initially designed with a brush on paper. Statues to be cast in bronze were modelled in wax. Patterns to be embroidered on tapestries were drawn on paper with ink wash. Buildings to be constructed from stone were tested on a smaller scale in wood.
What made oil paint so exciting, when it first became popular in the fifteenth century, was that you could actually make the finished work from the prototype. You could make a preliminary drawing if you wanted to, but you weren’t held to it; you could work out all the details, and even make major changes, as you finished the painting.
You can do this in software too. A prototype doesn’t have to be just a model; you can refine it into the finished product. I think you should always do this when you can. It lets you take advantage of new insights you have along the way. But perhaps even more important, it’s good for morale.
– Paul Graham, “Design and Research”
Mike and I have long been drawn by the idea that blog posts, like conference talks and posters, could be first drafts of research papers. In practice, we haven’t generated many successful examples. We basically wrote our 2013 neural spine bifurcation paper as a series of blog posts in 2012. And Mike’s 2014 neck cartilage paper grew out of this 2013 blog post, although since he accidentally ended up writing 11 pages I suppose the blog post was more of a seed than a draft.
I should also note that we are far from the first people to do the blog-posts-into-papers routine. The first example I know of in paleo was Darren’s Tet Zoo v1 post on azhdarchid paleobiology, which formed part of the skeleton of Witton and Naish (2008).
Nevertheless, the prospect of blogging as a way to generate research papers remains compelling.
And as long as I’m on about blogging and papers: sometimes people ask if blogging doesn’t get in the way of writing papers. I can’t speak for anyone else, but for me it goes in the opposite direction: I blog most when I am most engaged and most productive, and drops in blogging generally coincide with drops in research productivity. I think that’s because when I’m rolling on a research project, I am constantly finding or noticing little bits that are cool and new, but which aren’t germane to what I’m working on at the moment. I can’t let those findings interfere with my momentum, but I don’t want to throw them away, either. So I blog them. Also the blog gives me a place to burn off energy at the end of the day, when I can still produce words but don’t have the discipline to write technical prose.
– – – – – – – – – – – –
The photo at the top of the post is of Giraffatitan dorsal vertebrae in a case at the MfN Berlin, from Mike’s and my visit with the DfG 533 group back in late 2008. I picked that photo so I could make the following dumb off-topic observation: with its upturned transverse processes, the dorsal on the right looks like it’s being all faux melodramatic, a la:
This post started out as a comment on this thread, kicked off by Dale McInnes, in which Mike Habib got into a discussion with Mike Taylor about the max size of sauropods. Stand by for some arm-waving. All the photos of outdoor models were taken at Dino-Park Münchehagen back in late 2008.
I think it’s all too easy to confuse how big things do get from how big they could get, assuming different selection pressures and ecological opportunities. I’m sure someone could write a very compelling paper about how elephants are as big as they could possibly be, or Komodo dragons, if we didn’t have indricotheres and Megalania to show that the upper limit is elsewhere. This is basically what Economos (1981) did for indricotheres, either forgetting about sauropods or assuming they were all aquatic.
Truly, a mammal of excellence and distinction. With Mike and some dumb rhino for scale.
In fact, I’ll go further: a lot of pop discussions of sauropod size assume that sauropods got big because of external factors (oxygen levels, etc.) but were ultimately limited by internal factors, like bone and cartilage strength or cardiovascular issues. I think the opposite is more likely: sauropods got big because of a happy, never-repeated confluence of internal factors (the Sander/et al. [2008, 2011, 2013] hypothesis, which I think is extremely robust), and their size was limited by external, ecological factors.
Take a full-size Argentinosaurus or Bruhathkayosaurus – even modest estimates put them at around 10x the mass of the largest contemporary predators. Full-grown adults were probably truly predator-immune, barring disease or senescence. So any resources devoted to pushing the size disparity higher, instead of invested in making more eggs, would basically be wasted.
If there was reproductive competition among the super-giants, could the 100-tonners have been out-reproduced by the 70-tonners, which put those extra 30 tonnes into making babies? Or would the 100-tonners make so many more eggs than the 70-tonners (over some span of years) that they’d still come out on top? I admit, I don’t know enough reproductive biology to answer that. (If you do, speak up in the comments!) But if – if – 70-tonners could out-reproduce 100-tonners, that by itself might have been enough to put a cap on the size of the largest sauropods.
Another possibility is that max-size adult sauropods were neither common nor the target of selection. In most populations most of the time, the largest individuals might have been reproductively active but skeletally-immature and still-growing subadults (keep in mind that category would encompass most mounted sauropod skeletons, including the mounted brachiosaurs in Chicago and Berlin). If such individuals were the primary targets of selection, and they were selected for a balance of reproductive output and growth, then the few max-size adults might represent the relatively rare instances in which the developmental program “overshot” the selection target.
Dave Hone and Andy Farke and I mentioned this briefly in our 2016 paper, and it’s come up here on the blog several times before, but I still have a hard time wrapping my head around what that would mean. Maybe the max-size adults don’t represent the selective optimum, but rather beneficial traits carried to extreme ends by runaway development. It seems at least conceivable that the bodies of such animals might have been heavily loaded with morphological excrescences – like 15- to 17-meter necks – that were well past the selective optimum. As long as those features weren’t inherently fatal, they could possibly have been pretty darned inefficient, riding around on big predator-immune platforms that could walk for hundreds of kilometers and survive on garbage.
What does that swerve into weird-but-by-now-well-trod ground have to do with the limits on sauropod size? This: if max-size adults were not heavy selection targets, either because the focus of selection was on younger, reproductively-active subadults, or because they’d gotten so big that the only selection pressure that could really affect them was a continent-wide famine – or both – then they might not have gotten as big as they could have (i.e., never hit any internally-imposed, anatomical or biomechanical limits) because nothing external was pushing them to get any bigger than they already were.
Or maybe that’s just a big pile of arm-wavy BS. Let’s try tearing it down, and find out. The comment thread is open.
References
- Economos, A.C. 1981. The largest land mammal. Journal of Theoretical Biology 89(2):211-214.
- Hone, D.W.E., Farke, A.A., and Wedel, M.J. 2016. Ontogeny and the fossil record: what, if anything, is an adult dinosaur? Biology Letters 2016 12 20150947; DOI: 10.1098/rsbl.2015.0947.
- Sander, P.M. and Clauss, M. 2008. Sauropod gigantism. Science 322(5899):200-201.
- Sander, P.M., Christian, A., Clauss, M., Fechner, R., Gee, C.T., Griebeler, E.M., Gunga, H.C., Hummel, J., Mallison, H., Perry, S.F. and Preuschoft, H. 2011. Biology of the sauropod dinosaurs: the evolution of gigantism. Biological Reviews 86(1):117-155.
- Sander, P.M. 2013. An evolutionary cascade model for sauropod dinosaur gigantism-overview, update and tests. PLoS One, 8(10) p.e78573.
Brachiosaurus cervical BYU 12866 multi-view photos
January 9, 2018
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
- Wedel, M.J. 2005. Postcranial skeletal pneumaticity in sauropods and its implications for mass estimates. pp. 201-228 in Wilson, J. A., and Curry-Rogers, K. (eds.), The Sauropods: Evolution and Paleobiology. University of California Press, Berkeley.
- 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.
The giant brachiosaur cervical of Arches National Park
December 31, 2017
As Matt recently noted, we both have a ton of photos from various expeditions that we’ve never got around to posting — not to mention a ton of specimens that we’ve seen but never got around to working on. Here is one of the most exciting:
As you can see, this is a massive cervical vertebra from a sauropod, probably a brachiosaurid, eroding right out of the ground. It’s in an undisclosed location in the Arches National Park, which we visited in May 2016. The neural arch is in amazingly good shape, though the end of the right prezygapophysis has broken off and been displaced slightly upwards. The postzygapophysesal facet is difficult to make out. Here’s a rough-and-ready interpretive drawing to get you oriented, with the completely missing parts speculatively sketched in light grey. (We don’t know how much more of this vertebra might be preserved underground.)
Apart from its size, the most striking thing about this vertebra is how very pneumatic it is — corroborating the long-standing hypothesis that pneumaticity tends to be positively allometric. If you compare with the much-loved 8th cervical vertebra of the Giraffatitan brancai paralectotype MB.R.2181 (formerly HMN SII), you can see similar “sculpted” features on the arch of that vertebra, but they are much less developed and ramified:
(This photo is in of course in left dorsolateral view, whereas the aspect of the Arches vertebra available to us is right lateral, and slightly ventral of true lateral.)
How big is the Arches vertebra? Stupidly, we didn’t have measuring equipment with us when we were visiting the park, so we don’t have an exact figure. But we can get some idea by extrapolating from the photo above. The stretched-out arm-span of an adult man is close to his height. I’m 1.8 m tall, so allowing for the downward slope of my arms, we might guess that the fingertip-to-fingertip measurement is about 1.7 m. If that’s right, measuring off the photo, the preserved portion of the vertebra is nearly twice that, at 3.3 m — and the complete length must have been somewhat longer, as the back end of the centrum is completely missing. Something in the region of 3.6 m might not be too far out. But as always, note that these are extremely speculative figures based on multiple layers of approximation.
We really need to get back out there, measure that thing properly, and of course try to find a way to have it excavated.
It’s that time of year…
December 22, 2017
This year Santaposeidon comes to you courtesy of OMNH vert paleo head preparator and 20th-level fossil conservation wizard Kyle Davies, who took the photo, composed the card, and gave me kind permission to share it here. Needless to say, we’re happy to pass on the happy holiday wishes to all of you, wherever you are and whenever you are reading this.
For previous Santaposeidon sightings, please see:
- The ghost of Christmas past
- Here comes Santaposeidon
- A quick stop at the Oklahoma Museum of Natural History
