Speculative sauropod sketches of SVPCA 2012
September 18, 2012
Friday evening I was in a pub with Mike, Darren, John Conway, and Emma Lawlor. We were killing time waiting for the Pink Giraffe Chinese restaurant down the street to open. I was chatting with John about “All Todays”, his speculative presentation with Cevdet Kosemen (a.k.a. Nemo Ramjet) on how future sentients might reconstruct Holocene animals if they were known only from fossils. Like his “All Yesterdays” presentation last year, John’s flights of scientific fancy had fired my imagination and gotten me thinking about how paleontology forms sort of a skin or membrane between the bubble of what we know and the surrounding ocean of what we don’t. I decided that we should pass a pad around and each sketch a speculative sauropod.
My own entry is based on the holotype of Mamenchisaurus hochuanensis, which was found almost complete except for the skull (naturally) and forelimbs. I have often joked that diplodocids were basically bipeds whose forelimbs happened to reach the ground. Mamenchisaurs were probably not that back-heavy, but their presacral vertebrae were extremely pneumatic and if our hypothetical future paleontologists had no other sauropod material to work with, I think it’s possible that they would reconstruct the M. hochuanensis holotype as a biped.
I’m not sure there’s much to say about Mike’s brachiosaur, beyond the Ebert-like observation that if a brachiosaur dressed up in a coat and top hat and went cruising for dames, this, I am forced to conclude, is more or less how it would look.
John Conway also drew a mamenchisaur, this time Mamenchisaurus youngi with its bizarrely bent-back sacrum. John’s explanation for the weird sacrum brings to mind ground sloths and–for those who saw “All Yesterdays” at SVPCA 2011–a certain black-feathered therizinosaur. I’d also like to note that he knocked this out in about 5 minutes, thus demonstrating the difference between a professional artist and a mere doodler like myself.
Darren’s hindlimb-less sauropod complements my bipedal Mamenchisaurus. Here the animal, evidently known from only the front half of the skeleton, has been restored as a giant bird. Dig the giant thumb claws and spreading metapodials. Surely, you say, future paleontologists of any species or machine culture would know a pectoral girdle when they saw one. But I’ll bet a sauropod scapulocoracoid could pass for an ilium, if said future paleontologists were still in the early stages of understanding the morphology and diversity of vertebrates. Remember that Seeley described the sauropod Ornithopsis as “a gigantic animal of the pterodactyle kind” based on its pneumatic vertebrae. There is also a long and honorable (?) tradition of mistaking sauropods for hadrosaurs (Sonorasaurus), theropods (Bruhathkayosaurus), and tree trunks (Sauroposeidon), so don’t be too quick to rule this out.
What I want to see next is a skeletal reconstruction of Darren’s sauro-bird, using only elements from the front half of a sauropod skeleton. Anyone want to give it a shot?
Our penultimate entry is Emma’s rendering of an evil bastard snake devouring an innocent baby sauropod. Tragically this one is not speculative–we have very good fossil evidence that the scene shown here really happened, probably a lot. She tried to make it up to us with a smiley face on the next page, but it was too late. We were so depressed after this that we could barely choke down four courses of excellent Chinese food.
One more for the road: a totally new depiction of the enigmatic sauropod Xenoposeidon by yours truly. I expect to see this incorporated into future talks and papers dealing with European sauropod diversity in the Early Cretaceous. Just credit me as you normally would.
That’s all, folks. I hope that speculative sauropod sketches get to be a Thing, and that we see lots more of them from future conferences.
Hot sauropod news, part 2: A new look for Sauroposeidon
September 5, 2012
YPM 5449, a posterior dorsal vertebra of Sauroposeidon, from D’Emic and Foreman (2012:fig. 6A and C).
Another recent paper (part 1 is here) with big implications for my line of work: D’Emic and Foreman (2012), “The beginning of the sauropod dinosaur hiatus in North America: insights from the Lower Cretaceous Cloverly Formation of Wyoming.” In it, the authors sink Paluxysaurus into Sauroposeidon and refer a bunch of Cloverly material to Sauroposeidon as well. So in one fell swoop Sauroposeidon goes from being one of the most poorly represented Early Cretaceous North American sauropods, based on just four vertebrae from a single individual, to one of the best-known, most complete, and most widespread, based on at least seven individuals from Texas, Oklahoma, and Wyoming.
The web of connections among the different sets of material is complex, and involves the Sauroposeidon holotype OMNH 53062 from the Antlers Formation of southeastern Oklahoma, the type and referred material of Paluxysaurus from the Twin Mountains Formation of northern Texas described by Rose (2007), sauropod material from the Cloverly Formation of north-central Wyoming described and illustrated by Ostrom (1970), and UM 20800, a scap and coracoid newly excavated from one of Ostrom’s old quarries. D’Emic and Foreman argue that (1) the Cloverly material is referable to Sauroposeidon based on the shared derived characters of a juvenile cervical, YPM 5294, and the Sauroposeidon holotype, and (2) Paluxysaurus is not distinguishable from the Cloverly material and in fact shares several autapomorphies with the Cloverly sauropod. Which means that (3) Paluxysaurus is Sauroposeidon.
But that’s not all! All the new material suggests different phylogenetic affinities for Sauroposeidon. Instead of a brachiosaurid, it is now posited to be a basal somphospondyl. That’s not super-surprising; as we noted back in 2000 (Wedel et al. 2000), if Sauroposeidon was a brachiosaurid it had evolved some features in parallel with titanosaurs, most notably the fully camellate internal structure of the cervical vertebrae. And it also makes sense because other basal somphospondyls include Erketu and Qiaowanlong, the cervicals of which are similar to Sauroposeidon in some features. D’Emic and Foreman (2012) cite a forthcoming paper by Mike D’Emic in the Journal of Systematic Paleontology that contains the cladistic analysis backing all this up, but the case based on comparative anatomy is already pretty strong.
If anyone is unconvinced by all of these referrals, please bear in mind that we haven’t heard the whole story yet, quite probably for reasons that are outside of the authors’ control. I am inclined to be patient because I have been in that situation myself: Wedel (2003a) was intended to stand on the foundation of evidence laid down by Wedel (2003b), but because of the vagaries of publication schedules at two different journals, the interpretive paper beat the descriptive one into press by a couple of months.
Mid-cervical originally described as Paluxysaurus, now referred to Sauroposeidon, from Rose (2007:fig. 10).
Anyway, if anyone wants my opinion as “Mr. Sauroposeidon“, I think the work of D’Emic and Foreman (2012) is solid and the hypothesis that Paluxysaurus is Sauroposeidon is reasonable. So, if I think it’s reasonable now, why didn’t I synonymize the two myself? Partly because I thought there was a pretty good chance the two were not the same, based mostly on FWMSH 93B-10-8 (which I referred to as FWMSH “A” in Wedel 2003b, since I had only seen in on display without a specimen number), which I thought looked a lot more like a titanosaur cervical than a brachiosaur cervical. But of course I thought Sauroposeidon was a brachiosaur until a couple of months ago, and if it ain’t, and if brachiosaurs and basal somphospondyls have similar cervicals, that objection is considerably diminished. And partly because I’ve had other things to be getting on with, and stopping everything else to spend what would realistically be a few months looking into a possible synonymy (that I didn’t strongly suspect) wasn’t feasible in terms of time or geography. So I’m glad that D’Emic and Foreman have done that work, and I’m excited about the new things they’ve uncovered.
And I’m honored to bring you a new life restoration of Sauroposeidon by uber-talented Bob Nicholls, which we think is the first to show Sauroposeidon in its new guise as a basal somphospondyl. Click through for the mega-awesome version.
Same critter, different views. If anyone wants to GDI this baby, you now have everything you need. Many thanks to Bob for permission to post these and the following making-of images. Please visit him at Paleocreations.com to see a ton of awesome stuff, and give him some love–or at least a few thousand “likes”–on Facebook.
This is Bob’s first foray into 3D modeling, but you’d never know from the quality of his virtual sculpt. And let me tell you, that dude works fast. He sent this initial version, showing Sauroposeidon as an attenuated brachiosaur (sorta like this) on August 23, to solicit comments from Mike and me.
I wrote back and let Bob know about the new work of D’Emic and Foreman, and suggested that he could probably be the first to restore Sauroposeidon as a somphospondyl. Mike and I also voiced our opposition to the starvation-thinned neck, and Mike suggested that the forelimb was too lightly muscled and that the ‘fingers’ were probably too prominent. The very next day, this was in our inboxes:
I wrote back:
Whatever Sauroposeidon was, its neck was fairly tall and skinny in cross-section. It looks like the neck on your model sort of tapers smoothly from the front of the body to the head. I think it would be much narrower, side-to-side, along most of its length, and would have a more pronounced shoulder-step where it met the body.The bottom view is very useful. It shows the forefeet as being about the same size as the hindfeet. AFAIK all or nearly all known sauropod tracks have much bigger hindfeet than forefeet. Certainly that is the case with Brontopodus birdi, the big Early Cretaceous sauropod tracks from Texas that were probably made by Sauroposeidon. The forefeet should be about 75-80% the width of the hindfeet, and only about half a long front-to-back. Even if you don’t quite get to those numbers, shrinking the forefeet a bit and subtly up-sizing the hindfeet would make the model more accurate.
I like how freaky it looks. It looks WRONG, but in a good way.
I had one more change to recommend:
I’m sorry I didn’t suggest this sooner, but it only just now occurred to me. With the referral of Paluxysaurus and the Cloverly material to Sauroposeidon, we now have dorsal vertebrae, and they are loooong, much more similar in proportion to the dorsals of Brachiosaurus altithorax than those of Giraffatitan brancai. So, as much as I like the compact little body on your Sauroposeidon, I think it was probably fairly long in the torso. You probably already have Mike’s Brachiosaurus paper [Taylor 2009] with the skeletal recon showing the long torso–in the absence of an updated skeletal recon for Sauroposeidon, I’d use Mike’s Figure 7 as a guide for reconstructing the general body proportions.
Bob lengthened the torso to produce the final version, which is the first one I showed above. He sent that over on August 29–the delay in getting this post up rests entirely with me.
So. It is still very weird to think of “my” dinosaur as a somphospondyl rather than a brachiosaur. I had 15 years to get used to the latter idea. But suddenly having a lot more material–essentially the whole skeleton, minus some stinkin’ skull bits–is pretty darned exciting, and the badass new life restoration doesn’t hurt, either.
Now, would it be too much to wish for some more Brontomerus?
References
- D’Emic, M.D., and B.Z. Foreman. 2012. The beginning of the sauropod dinosaur hiatus in North America: insights from the Lower Cretaceous Cloverly Formation of Wyoming. Journal of Vertebrate Paleontology 32(4): 883-902.
- Ostrom, J.H. 1970. Stratigraphy and paleontology of the Cloverly Formation (Lower Cretaceous) of the Bighorn Basin area, Wyoming and Montana. Peabody Museum Bulletin 35: 1-234.
- Rose, Peter J. 2007. A new titanosauriform sauropod (Dinosauria: Saurischia) from the Early Cretaceous of central Texas and its phylogenetic relationships. Palaeontologia Electronica 10(2): 8A (65 pp.)
- Taylor, Michael P. 2009. A re-evaluation of Brachiosaurus altithorax Riggs 1903 (Dinosauria, Sauropoda) and its generic separation from Giraffatitan brancai (Janensch 1914). Journal of Vertebrae Paleontology 29(3): 787-806.
- Wedel, M.J. 2003a. Vertebral pneumaticity, air sacs, and the physiology of sauropod dinosaurs. Paleobiology 29: 243-255.
- Wedel, M.J. 2003b. The evolution of vertebral pneumaticity in sauropod dinosaurs. Journal of Vertebrate Paleontology 23: 344-357.
- 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.
I don’t have time to write about this properly, but a few people have asked me about the new Sellers et al. (2012) paper on measuring the masses of extinct animals — in particular, the Berlin Giraffatitan — by having a CAD program generate minimal complex hulls around various body regions. Rather than write something new about it, I’m going to publish the comments that I sent Ed Yong for his Discover piece on the new technique:
Hi, Ed, good to hear from you. Yes, it’s a good paper: a useful new technique that has some useful properties, most importantly that it requires no irreproducible judgements on the part of the person using it, and that it’s ground-truthed on solid data from extant animals.
It’s a reassuring sanity-check to find that my (2009) mass estimate falls well within their method’s 95% confidence interval, and is in fact within 0.6% of their best estimate.
There are a couple of problems with this study, which I hope will be addressed in followups. The authors are honest enough to touch on all of these problems themselves, though! They are:
1. All the extant animals used to determine the fudge factor are mammals, which means they are not necessarily completely relevant to dinosaurs. In particular I would very much like to have seen regression lines and correlation coefficients for this method for birds and crocodilians, both of which are much more closely related to Giraffatitan.
2. Much depends on the reconstruction of the torso, particular the position of the ribs, which is very difficult to do well and confidently with dinosaurs. In my volumetric analysis (Taylor 2009:803) I found that the torso accounts for 70% of total body volume in Giraffatitan, so rib orientation will make a big difference to overall mass. Sauropod ribs that are well preserved and undistorted along their whole length are extremely rare.
3. Use of a single density value for the whole animal, while appropriate for mammals, really isn’t for brachiosaurs, in which the very long neck likely had a density no more than half that of the legs. I’m not sure what can be done about this, though, since any attempt to correct for density variation involves subjective guesswork. Then again, so do all guesses at overall body density in dinosaurs.
Issue 1 bothers me most, because the convex hulls of limb segments in mammals will be proportionally much larger than in sauropods, due to the complex shapes of mammalian long-bone ends. I worry that using mammals as a baseline will underestimate sauropod leg mass.
Still, even with these caveats, it’s a good exposition of an important new method which I expect to see widely adopted.
Hope that’s helpful.
In short: good work, widely applicable, and probably the best mass-estimation technique we now have available for complete and near-complete skeletons. It would be good to see it applied to (say) the Yale, AMNH and CM apatosaurs.
Composite illustration from Sellers et al.’s press release. Top left: bear skeleton from the Oxford University Natural History Museum, presumably Ursus maritimus: original skeleton, derived point cloud and convex hulls (also used as Sellers et al. 2012:fig. 1). Top right: shedloads of awesome. Bottom: complex hulls around body segments of Giraffatitan.
References
The sacrum of Brachiosaurus
May 12, 2012
In my 2009 brachiosaur paper, I gave rather short shrift to the sacrum of Brachiosaurus — in part because there is no really good sacrum of Giraffatitan to compare it to. Also my own photos of the sacrum, taken back before I figured out how to photograph big bones, are all pretty terrible.
Happily, Phil Mannion took some much better photos and gave us permission to use them. So I prepared this multi-view figure, which we plan to use in a forthcoming paper about another sacrum:
At the bottom, we have the sacrum in left lateral view; above it, in dorsal view. To the left is the anterior view (with dorsal to the right) and the right is the posterior view (with dorsal to the left). The idea of this composition is that you could print the image out, and cut and fold it into a cuboid. (In fact I might just do that.)
As usual with these things, click through for the much more impressive full-resolution version (3809 x 3157 pixels).
MOLD-A-RAMA
May 3, 2012
I’m in Chicago, visiting the Field Museum, which means two things: Brachiosaurus (see below), and Mold-A-Rama. Downstairs from the great hall, on the ground floor, they have Mold-A-Rama machines, and I cannot resist their siren song.
The Mold-A-Rama is the king of novelty souvenirs. You can keep your stamped pennies, little pewter spoons, hand-painted bells, and refrigerator magnets. None of them is worthy to sully the presence of the awesome Mold-A-Rama. You put in two dollars, and then you get to watch as this hissing, clanking 1950s machine with tubes and wires and lights actually makes your item right in front of your eyes. A few minutes later, BAM, you’re holding a hot, smelly hunk of probably carcinogenic plastic that is so fresh from the mold that it is still a bit soft. You can’t buy that kind of authenticity–except from a Mold-A-Rama.
See that red thing, newly made, still in the bowels of the machine? That is MY T. rex!
This is my first Mold-A-Rama Triceratops. I already have a T. rex from my last visit, way back in 2005, which I can now pass on to my son. I also have a Stegosaurus, a Brontosaurus (shown but not commented on here), and a Trachodon. Yeah, yeah, I know the real animals are known as Apatosaurus and Edmontosaurus these days, but I’m not talking about the real animals. I’m talking about Mold-A-Rama, and trust me, the Mold-A-Rama critters are Brontosaurus and Trachodon. They drag their tails, they live in swamps, they’re cold-blooded and they died out from racial senescence (in about 1975, I think).
Finally, because Mike will straight-up murder me if I post from Chicago without it, here’s your friendly local not-quite-fully-mature mounted holotype specimen of Brachiosaurus:
Neural spine bifurcation in sauropods, Part 6: more reasons why Haplocanthosaurus is not a juvenile of a known diplodocid
April 15, 2012
Last time, we saw why Haplocanthosaurus couldn’t be a juvenile of Apatosaurus or Diplodocus, based on osteology alone. But there’s more:
Ontogenetic status of Haplocanthosaurus
Here is where is gets really surreal. Woodruff and Fowler (2012) blithely assume that Haplocanthosaurus is a juvenile of something, but the type specimen of the type species — H. priscus CM 572 — is an adult. As Hatcher (1903:3) explains:
The type No. 572 of the present genus consists of the two posterior cervicals, ten dorsals, five sacrals, nineteen caudals, both ilia, ischia and pubes, two chevrons, a femur and a nearly complete series of ribs, all in an excellent state of preservation and pertaining to an individual fully adult as is shown by the coössified neural spines and centra.
So far as I can see, Woodruff and Fowler are confused because the second species that Hatcher describes, H. utterbacki, is based on the subadult specimen CM 879. Where possible in the previous post, I have used illustrations of the adult H. priscus, so that the comparisons are of adult with adult. The exceptions are the two anterior cervicals and the first dorsal, which are known only from H. utterbacki. And sure enough, if you look closely at the illustrations, you can see that in these vertebrae and only these vertebrae, Hatcher had the neurocentral junction illustrated — because it wasn’t yet fused.
Haplocanthosaurus posterior, mid and anterior cervical vertebrae, C14, C9 and C4, in right lateral view. C14 of adult H. priscus (from Hatcher 1903:plate I); C9 and C4 of H. utterbacki (from plate II). Red ellipses highlight neurocentral sutures.
As it happens, the difference in ontogenetic status between these two specimens is nicely illustrated by Wedel (2009), although he was only in it for the pneumaticity:
Neurocentral fusion in Haplocanthosaurus. A, B. Posterior cervical vertebra C?12 of sub-adult H. utterbacki holotype CM 879: A, X-ray in right lateral view; B, coronal CT slice showing separate ossificaton of centrum and neural arch. C, D. Mid-dorsal vertebra D6 of adult H. priscus holotype CM 572: X-rays in (A) right lateral and (B) anterior view, showing fully fused neural arch. Wedel (2009:fig. 6)
So H. utterbacki CM 879 certainly is an immature form of something; and that something is Haplocanthosaurus, most likely H. priscus. (The characters which Hatcher used to separate the two species are not particularly convincing.)
With that out the way, we can move on to …
Phylogenetic analysis
A simple way to evaluate the parsimony or otherwise of a synonymy is to use a phylogenetic analysis. In their abstract, Woodruff and Fowler claim that “On the basis of shallow bifurcation of its cervical and dorsal neural spines, the small diplodocid Suuwassea is more parsimoniously interpreted as an immature specimen of an already recognized diplodocid taxon”. Without getting into the subject of Suuwassea again — Matt pretty much wrapped that up in part 4 — the point here is that the word “parsimony” has a particular meaning in studies of evolution: it refers to minimising the number of character-state changes. And we have tools for measuring those.
So let’s use parsimony to evaluate the hypothesis that Haplocanthosaurus is one of the previously known diplodocids. Pretending for the moment that Haplocanthosaurus really was known only from subadults, how many additional steps would we need to account for if ontogeny were to change its position to make it group with one of the diplodocids?
You don’t need to be a cladistics wizard to do this. (Which is handy, since I am not one.) Here’s the method:
- Start with an existing matrix, add constraints, re-run it, and see how the tree-length changes. Since I am familiar with it, I started with the matrix from my 2009 paper on brachiosaurs.
- Re-run the matrix to verify that you get the same result as in the published paper based on it. This gives you confidence that you’re running it right. In this case, I got a minimum tree length of 791 steps, just as in Taylor (2009).
- Add extra instructions to the run-script defining and imposing constraints. Note that you do not have to mess with the characters, taxa or codings to do this.
- Run the matrix again, with the constraint in place, and see how the tree-length changes.
- Repeat as needed with other constraints to evaluate other phylogenetric hypotheses.
(This is how we produced the part of the Brontomerus paper (Taylor et al. 2011:89) where we said “One further step is sufficient to place Brontomerus as a brachiosaurid, a basal (non−camarasauromorph) macronarian, a basal (non−diplodocid) diplodocoid or even a non−neosauropod. Three further steps are required for Brontomerus to be recovered as a saltasaurid, specifically an opisthocoelicaudiine”. And that’s why we weren’t at all dogmatic about its position.)
Anyway, going through this exercise with Haplocanthosaurus constrained in turn to be the sister taxon to Apatosaurus, Diplodocus, etc., yielded the following results:
- (no constraint) – 791 steps
- Apatosaurus — 817 (26 extra)
- Diplodocus — 825 (34 extra)
- Barosaurus — 815 (24 extra)
- Camarasaurus — 793 (2 extra)
- Brachiosaurus — 797 (6 extra)
(I threw in the other well-known Morrisson-Formation sauropods Camarasaurus and Brachiosaurus, even though Woodruff and Fowler don’t mention them, just because it was easy to do and I was interested to see what would happen. And when I say Brachiosaurus, I mean B. altithorax, not Giraffatitan.)
I hope you’re as shocked as I am to see that for Haplocanthosaurus to emerge as the sister taxon of any diplodocid needs a minimum of 24 additional steps — or an incredible 34 for it to be sister to Diplodocus. In other words, the hypothesis is grossly unparsimonious. Of course, that doesn’t in itself mean that it’s false: but it does render it an extraordinary claim, which means that it needs extraordinary evidence. And while “the simple spines of Haplocanthosaurus might bifurcate when it grows up” is extraordinary evidence, it’s not in the way that Carl Sagan meant it.
In short, running this simple exercise — it took me about a hour, mostly to remember how to do constraints in PAUP* — would have given Woodruff and Fowler pause for thought before dragging Haplocanthosaurus into their paper.
Oh, and it’s ironic that placing Haplo as sister to Brachiosaurus requires only a quarter as many steps as the closest diplodocid, and as sister to Camarasaurus requires only two steps. If you really want to synonymise Haplocanthosaurus, Camarasaurus is the place to start. (But don’t get excited, it’s not Camarasaurus either. It’s Haplocanthosaurus.)
[By the way, anyone who'd like to replicate this experiment for themselves is welcome: all the files are available on my web-site. You only really need the .nex file, which you can feed to PAUP*, but I threw in the log-file, the generated tree files and the summary file, too. Extra Credit: run this same exercise to evaluate the parsimony of Suuwassea as a subadult of one of these other genera. Report back here when you're done to earn SV-POW! points.]
Conclusion
It’s a truism that we stand on the shoulders of giants. In the case of sauropod studies, those giants are people like J. B. Hatcher, Charles Gilmore, Osborn and Mook and — bringing it up to date — John McIntosh, Paul Upchurch, Jeff Wilson and Jerry Harris. When Hatcher described Haplocanthosaurus as a new genus rather than a subadult Diplodocus, he wasn’t naive. He recognised the effects of ontogeny, and he was aware that one of his two specimens was adult and the other subadult. He was also probably more familiar with Diplodocus osteology than anyone else has ever been before or since, having written the definitive monograph on that animal just two years previously (Hatcher 1901).
By the same token, people like Upchurch and Wilson have done us all a huge favour by making the hard yards in sauropod phylogenetics. If we’re going to go challenging the standard consensus phylogeny, it’s just good sense to go back to their work (or the more recent work of others, such as Whitlock 2011), re-run the analyses with our pet hypotheses encoded as constraints, and see what they tell us.
So in the end, my point is this: let’s not waste our giants. Let’s take the time to get up on their shoulders and survey the landscape from up there, rather than staying down at ground level and seeing how high we can jump from a standing start.
The rest of the series
Links to all of the posts in this series:
- Part 1: what we knew a month ago
- Part 2: why serial position matters
- Part 3: the evidence from ontogenetic series
- Part 4: is Suuwassea a juvenile of a known diplodocid?
- Part 5: is Haplocanthosaurus a juvenile of a known diplodocid?
- Part 6: more reasons why Haplocanthosaurus is not a juvenile of a known diplodocid
and the post that started it all:
References
- Hatcher, J.B. 1901. Diplodocus (Marsh): its osteology, taxonomy, and probable habits, with a restoration of the skeleton. Memoirs of the Carnegie Museum 1:1-63.
- Hatcher, J.B. 1903. Osteology of Haplocanthosaurus with description of a new species, and remarks on the probable habits of the Sauropoda and the age and origin of the Atlantosaurus beds; additional remarks on Diplodocus. Memoirs of the Carnegie Museum 2:1-75.
- Taylor, M.P. 2009. A re-evaluation of Brachiosaurus altithorax Riggs 1903 (Dinosauria, Sauropoda) and its generic separation from Giraffatitan brancai (Janensch 1914). Journal of Vertebrate Paleontology 29(3):787-806.
- Taylor, M.P., Wedel, M.J. and Cifelli, R.L. 2011. A new sauropod dinosaur from the Lower Cretaceous Cedar Mountain Formation, Utah, USA. Acta Palaeontologica Polonica 56(1):75-98. doi:10.4202/app.2010.0073
- Wedel, M.J. 2009. Evidence for bird-like air sacs in saurischian dinosaurs. Journal of Experimental Zoology 311A:611-628.
- Whitlock, J.A. 2011. A phylogenetic analysis of Diplodocoidea (Saurischia: Sauropoda). Zoological Journal of the Linnean Society 161(4):872-915. doi: 10.1111/j.1096-3642.2010.00665.x
- Woodruff, D.C, and Fowler, D.W. 2012. Ontogenetic influence on neural spine bifurcation in Diplodocoidea (Dinosauria: Sauropoda): a critical phylogenetic character. Journal of Morphology, online ahead of print.
Academic Spring and a declaration of independence
February 9, 2012
I only became aware of the term Academic Spring the other day but I instantly loved it. The OA wars have heated up significantly in the past few weeks, and Academic Spring crystallizes a lot of what is going on.
Although we always welcome new readers, and no-one who cares about science can afford to be ignorant about access to scholarly publications, we do sometimes feel that at SV-POW! we are mostly preaching to the converted. But access is not just a problem for scientists and academics, it’s a problem for everyone, including physicians, patient groups, engineers, small business owners, students, and, frankly, anydamnbody who wants to inspect the fruits of the research their taxes paid for. So it’s important to get the message out, broadly, to the most people possible, in as many venues as possible, until Joe and Jane Citizen get mad enough about the situation to demand better behavior by their elected representatives and better service from the corporations that allegedly have their interests at heart.
To that end, Mike has a new piece up at The Independent today. Because he couldn’t assume that his readers would be familiar with the OA wars or Academic Spring, he had to lay out the whole case in a limited number of words. I think he did a bang-up job. Because the piece is so self-contained (although it has some choice links that are worth following up), it serves as a front-line report for those of us familiar with the OA wars, and a solid overview for everyone else. Go check it out.
Finally, since you haven’t gotten a lot of sauropod action lately, here are some small Giraffatitan humeri in the basement of the Museum für Naturkunde with Vanessa Graff for scale. You can tell these are small ones because they’re Vanessa-sized or smaller; the big ones are taller than I am…and they’re still from subadults. Must blog sometime about the awesomeness of the basement full o’ sauropods at the MfN, but not today. Excelsior!
Want free-to-use silhouettes of organisms? PhyloPic is here!
February 3, 2012
I’m very aware that I’ve been whining incessantly on this blog recently: RWA this, Elsevier that, moan whine complain. So I’m delighted to be able to bring some good news. Mike Keesey’s site PhyloPic.org is back up, in new and improved form, and providing free silhouettes of organisms extincts and extant. To quote the site’s FAQ:
PhyloPic‘s database stores reusable silhouette images of organisms. Each image is associated with one or more taxonomic names and indicates roughly what the ancestral member(s) of each taxon looked like.
PhyloPic also stores a phylogenetic taxonomy of all organisms. This means that you can perform phylogenetic searches. For example, if you need an image for a certain taxon, but there is no exact match in the database, you can easily search that taxon’s supertaxa, subtaxa, and related taxa for an image that may work as well.
For example, there is a page about Giraffatitan brancai, which includes a link to a silhouette by Scott Hartman; and a page about Brachiosaurus altithorax, which has two silhouettes — one by Scott and one by me.
More interestingly, for each taxon, you can ask for an illustrated lineage. For example, the illustrated lineage of Giraffatitan brancai starts with that animal, then works its way up via images for Brachiosauridae, Titanosauriformes, Camarasauromorpha, and continues up through a total of 36 images, finishing up with Holozoa, Cytota and Panbiota.
Better still, because all the images are available to re-use (subject to some restrictions which I’ll discuss below), you’re free to use them to make collages like this one, which Mike Keesey did for our friend Giraffatitan brancai:
One of the great things about this site is that it’s a community effort: Mike built the site and has prepared a good chunk of the artwork so far, but PhyloPic is open to submissions from anyone who cares to register (or to login via Google, Twitter, etc.)
Mike has allowed some latitude in the licences that can be used when images are added. You can currently choose from any of:
- Public Domain Mark 1.0 [for declaring that an image is already PD]
- Public Domain Dedication 1.0 [for putting an image into the PD]
- Creative Commons Attribution 3.0 Unported
- Creative Commons Attribution-Noncommercial 3.0 Unported
- Creative Commons Attribution-ShareAlike 3.0 Unported
- Creative Commons Attribution-Noncommercial-ShareAlike 3.0 Unported
That choice is nice for contributing artists, but makes life a bit more awkward for users because any composite artwork has to be licenced under the most restrictive combination of the licences of its parts. In the case of the collage above, because Scott’s Giraffatitan brancai was uploaded as CC-BY-NC-SA, that’s how the whole image ends up, too. This means that if, say, you want to make T-shirts on Cafe Press with this image on them, you’ll have a bit of nightmare figuring out exactly who you need to get permission from.
Mike has to walk a fine line with this. The images would be most useful to the world if they were all public domain and could be remixed, reused and reproduced with no restrictions whatsoever; but you can’t blame artists for wanting to put some limits on this. Yet even when the most permissive non-public domain licence is used (CC-BY), the light requirement that the image must be credited ends up as a heavy requirement when, as with the collage above, you use thirty images that all need to be acknowledged.
Anyway, these are wrinkles. The point is: free, re-usable art! Go and use it; and add to it!
And a happy Christmas from me, too!
December 23, 2011
Necks, I win; tails, Wedel loses –or– The SV-POW! Palaeo Paper Challenge
December 14, 2011
This year, I missed The Paleo Paper Challenge over on Archosaur Musings — it was one of hundreds of blog posts I missed while I was in Cancun with my day-job and then in Bonn for the 2nd International Workshop on Sauropod Biology and Gigantism. That means I missed out on my annual tradition of promising to get the looong-overdue Archbishop description done by the end of the year.
Brachiosauridae incertae sedis NMH R5937, "The Archbishop", dorsal neural spine C, probably from an anterior dorsal vertebra. Top row: dorsal view, anterior to top; middle row, left to right: anterior, left lateral, posterior, right lateral; bottom row: ventral view, anterior to bottom.
But this year, Matt and I are going to have our own private Palaeo Paper Challenge. And to make sure we heap on maximum pressure to get the work done, we’re announcing it here.
Here’s the deal. We have two manuscripts — one of them Taylor and Wedel, the other Wedel and Taylor — which have been sitting in limbo for a stupidly long time. Both are complete, and have in fact been submitted once and gone through review. We just need to get them sorted out, turned around, and resubmitted.
(The Taylor and Wedel one is on the anatomy of sauropod cervicals and the evolution of their long necks. It’s based on the last remaining unpublished chapter of my dissertation, and turned up in a modified form as my SVPCA 2010 talk, Why Giraffes Have Such Short Necks. The Wedel and Taylor one is on the occurrence and implications of intermittent pneumaticity in the tails of sauropods, and turned up as his SVPCA 2010 talk, Caudal pneumaticity and pneumatic hiatuses in the sauropod dinosaurs Giraffatitan and Apatosaurus.)
We’re going to be realistic: we both have far too much going in (incuding, you know, families) to get these done by the end of 2011. But we have relatively clear Januaries, so our commitment is that we will submit by the end of January 2012. If either of us fails, you all have permission to be ruthlessly derisive of that person.
… and in other news …
Some time while we were all in Bonn, the SV-POW! hit-counter rolled over the One Million mark. Thanks to all of your for reading!
