Recently I saw some pretty impressive dinosaur remains that evade description. These are tough. They're even stumping me, believe it or not.
Of course they are hips.
Sauropod hips are usually pretty easy to identify. The basal ones are pretty simple, relatively small ilium and the ischium and pubis of similar length and lightly built.
Then you have diplodocoid hips, which have big rounded ilia and very tall sacral spines:
Camarasaurs have similar ilia but much squatter and even more completely fused sacrals.
Brachiosaur hips are relatively rare in the fossil record (or at least complete described and published ones seem to be). Overall they are wide and extensively fused in the sacrals to support more weight, and have tall ilia with the front end much larger and taller than the back end.
|Brachiosaurus altithorax (sacrum). Note the hypantrum gap at the front of the sacrum, and flat-topped prezygapophyses on either side of it. This will be useful later.|
|Brachiosaurus altithorax (right ilium)|
And then you have titanosaur hips, which always tend to be super-wide (in this case even wider than they are long) and super-heavily fused. The ilia are flared out to a downright crazy extent, so the rib cage would have been easily twice as wide as most of the earlier sauropod types. These giants just seemed to be getting fatter and fatter every few million years as the Cretaceous ground on.
|Futalognkosaurus dukei complete pelvis (ventral view)|
|Futalognkosaurus dukei complete pelvis (front view)|
And then of course you have the stuff that can only border on fantasy:
|not sure if this ever was a dinosaur sacrum, or just a weird rock...|
Okay, so on to the star attraction.
A few pics from Heinrich Mallison's blog caught my eye, I had never seen these before and apparently they are from the Utah Field House of Natural History State Park Museum in Vernal, Utah. We're talking basement vault stuff, locked away far out of view of the museum visitors.
|two whatchamacallits... seriously these are weird.|
Neither one of these two specimens have been formally described or assigned to any known species.
The pelvis on the left, on the green-tinted forklift pallet, is obviously the taller and less squat of the two. The ilia still flare out a bit and it appears rather front-heavy, so this may be a brachiosaur or a basal titanosaur. The Potter Creek ilium discovered by Jensen (1985) in Utah also seems to have a mix of features from both groups, and may belong to an intermediary family.
The pelvis on the right is far flatter and more interesting. Its neural spines look a bit Giraffatitan-like but that's where the similarity ends. This pelvis is very wide with super-flared out ilia. Most likely a titanosaur. But lets look closer (keep in mind there's only one species of true titanosaur known from Utah, or the entire United States for that matter).
|The squat pelvis from the front. Note the tight space between the prezygapophyses, and the fact that it's a good bit above the neural canal|
This thing definitely looks like a titanosaur, but not any that I've seen. A tight, high hypantrum with enough clearance above the neural canal to accommodate a real hyposphene from the final dorsal vertebra (basal titanosaur trait), yet extremely wide hips with super-flared ilia (derived titanosaur trait).
How does it stack up?
|Alamosaurus sanjuanensis (referred big bend specimen - pelvis cast, dorsal view. Note the neural spines are separate at the tip - beware that this may be a speculative reconstruction because in many drawings you see them looking fused)|
|Trigonosaurus pricei partial pelvis, dorsal view. Once again, note the neural spines are distinctly separate at the tip.|
|Saltasaurus loricatus pelvis - the neural spines and top of the ilia and sacral rib connections are eroded, but you can still see that the neural spines were configured as having distinctly separate tips.|
|Malawisaurus dixeyi - sacrum from above and below. A transitional titanosaur. Note the HEAVY fusion of the neural spines into a single piece by ossified ligaments.|
|Unnamed Brazilian titanosaur pelvis - note the heavy fusion of the neural spines with ossified ligament. Also the gap between the prezygapophyses is shallow, and not very far above neural canal. The opposite condition to the Utah pelvis.|
And finally... the Utah pelvis again:
So we have the Utah pelvis having some basal traits (brachiosaur-like neural spine "fan-tips" and well-developed deep and high hypantrum which interlocked with a big hyposphene on the last dorsal in front of it) as well as some traits of derived titanosaurs (extremely wide flaring in the ilia and largely unfused neural spine tips as in Trigonosaurus and Saltasaurus - yet this latter trait is also present in the far more basal Euhelopus). Yes, they are mostly unfused at the tips in this sacrum. Here's the proof: a panoramic 3D model by Heinrich Mallison.
|The middle four spines are tightly packed together (a common feature of many sauropods) but the tips are still distinct and are not fused into a single straight-edged block like Malawisaurus or the unnamed Brazilian taxon.|
Overall the shape of the sacral spines and the twist in the sacral ribs reminds me of Giraffatitan, with the front and middle spines less completely fused, but this is clearly a much wider set of hips.
Whatever this animal is, it looks like a basal titanosaur, but with the extremely wide hips of a derived one. Things get even more complicated when you realize that there's only one true titansoaur known from the United States (and it's native to Utah too), Alamosaurus. A very derived titanosaur which did NOT have a hypantrum-hyposphene connection. Critically, it was an immigrant from South America, at the time when the land bridge of Panama took shape (Late Cretaceous, Campanian epoch) - before this the two continents were isolated, and North America was known to be nearly devoid of sauropods - the basal titanosauriforms of the Early Cretaceous (Venenosaurus, Paluxysaurus, Brontomerus, etc.) had already gradually died out. So the Vernal pelvis is clearly no Alamosaurus. But what is it?
Are we looking at a basal titanosauriform somewhere on the family tree between brachiosaurs and true titanosaurs? Perhaps a Phuwiangosaurus or Paluxysaurus-like creature? Or is this a derived titanosaur similar to Trigonosaurus, with a ridiculous level of throwbacks to its hypantrum-bearing ancestors? In the absence of knowing the creature's age (which would be a big key to figuring out its relationships given the big sauropod-devoid Mid-Cretaceous time gap in North America), what can we deduce from the fossil itself?
And what's more, is this animal a totally "new" species, or a more complete specimen of something we already knew about?
YOU DECIDE... I'd like to see everyone's thoughts.
Some really interesting stuff here. First off, the last "name that dinosaur" contest was a good one, Zach Armstrong won. It was indeed the La Invernada titanosaur, a relatively small species that doesn't have a name but is pasted all over South American paleontology websites. The reasonably complete foot allows us to place this animal at the hub of lithostrotia, close to Epachthosaurus.
Second, the bizarre derived titanosaur Yongjinglong datangi has been described in PLoS One. A crowning moment for both Chinese paleontology and open-access research. So long Cretaceous Research, Acta Geologica Sinica and other paywalled journals.This odd creature is from the Hekou Group, so it was probably in the same ecosystem as Huanghetitan and Daxiatitan. Details here.
But the craziest thing to come to my attention is from an old favorite.
I just realized while looking at revising my Giraffatitan skeletal that most previous restorations seem to have either botched the shape of some of the dorsals to look too generic or followed Dr. Werner Janensch's rather hasty full body skeletal instead of his far more detailed engravings of the actual fossil material of the primary specimen, HMN SII.
Here's my original reconstruction, which you can see on DeviantArt:
This uses SII as well as a number of other specimens to fill in the hindlimbs, shoulders, hips, head and tail. Lets take a look at the dorsals.
There's a bit of uncertainty as to which dorsal was truly the last. However, the last two shown in this reconstruction right before the sacrum (the ones whose neural spines seem to neatly interlock with each other) are fused at the centrum joint. HMN SII was a subadult individual (judging by the lack of fusion in the coracoid, and unfused scapula found in similar-sized individuals) that either was getting near puberty or had some unique pathologies such as DISH or ankylosing spondylitis (this pair of bones shows some ossified ligaments on the neural spines which may also have fused together given enough time). This pair of fused rear dorsals is labeled as D11 and D12 (the final two dorsals) by Taylor (2009), but if you follow Janensch (1950) they should actually be D10 and D11. D12 on the other hand, looks as illustrated on the left in the image below.
|Last 3 dorsals in Giraffatitan, from HMN SII and the even larger HMN fund no. (which also includes the caudal series that Janensch frankensteined onto the rear end of SII).|
However the main point to take note of isn't even this discrepancy, but rather the bone that sits in front of the fused pair in the SII specimen. Note the red box around this bone.
The dorsal vertebra in front of the fused pair has a long centrum. In fact, it looks freakishly long because of vertical crushing. I have "uncrushed" it a bit. The original is so bizarre it looks like it came from a totally different species, but it was found together with the rest of the same specimen.
Now even if you correct for crushing, that's still going to be a very long centrum compared to the vertebrae both before and behind this one. And its rear rim has a totally different angle from the other centra, meaning that between this bone and the next one down (the first on the fused pair) there is an odd dip in the spine, a sort of "lordosis" or "anti-hunchback" posture. And however you restore the end of the centrum (its upper portion is missing and represented by a dotted line here), there is still going to be a BIG gap between the neural spine of this vertebra and the next (even with the spine tilted the correct way, uncrushed). But the gap is often ignored in the schematic literature.
|Four different reconstructions of the Giraffatitan torso, primarily based on HMN SII. (A) Greg Paul, 1988; (B) Scott Hartman, 2012; (C) Asier Larramendi, 2013; (D) Nima Sassani, 2011.|
None of these have the order correct with the D12 based on Janensch (HMN fund no 8). One of the two speculative middle dorsals has to be removed to make room for D12 at the back end and still keep the count at 12 dorsal vertebrae, which is typical of basal titanosauriformes. But notice how some of these skeletals (notable mine and Asier's) do show the big gap and also the odd "return up" of the subsequent fused pair's neural spines. Greg Paul ignores this feature but does at least half-bake the gap, while Scott Hartman totally omits both of these very distinctive features. But they are natural and can't solely be attributed to crushing.
The point is that the dorsal column as a whole needs to be reworked. In fact the dorsals of HMN SII are a lot less complete than often believed.
|HMN SII + HMN fund no 8 (D12, scaled down by 10% to SII)|
This is even more bizarre than previously thought. With just the baseline amount of de-crushing necessary to make the vertebrae articulate, so that we avoid unnecessary artificial distortions, the spine is kinked at both ends of the by-now-notorious Dorsal 9. Even it you ignore the pathology argument (and you probably should, since D9, D10 and D11 are all very symmetrical, with no anomalies in lateral curvature), the odd shape and angle of D9 is even stranger than even myself and Asier Larramendi had restored it. While the gap between it and the fused pair is now smaller in the neural spines (which makes sense since the tips of the spines in D9 and D10 almost interlock at this angle), the gap below the zygapophyses (which the spinal cord would have run through) is still gigantic. Woe betide any young Giraffatitan that got bitten there.
Another interesting feature is that there seems to be another dip between dorsals 3 and 4, (or rather an upcurve of the anterior dorsals at D3) which may mean that the tall neural spines in this region came out looking less hump-like than traditionally depicted, and the spine profile of the live animal may have actually been more of a straight incline. And this would clearly make the angle of the anterior dorsals steeper and the neck even higher and more vertical... without having to add an insane amount of upward kink at the base of the neck the way Research Casting International did for the updated Berlin mount of Giraffatitan. I suppose it was easier to alter one joint than redo four of them, but then again closer attention should have been paid to how they reconstructed those other anterior dorsals in the first place. Janensch wasn't making up the shape of the cotyles, and D3 and D4 show very little vertical crushing. There should actually be an upcurve at D3, not a downcurve or a hump.
Even Greg Paul's new 2010 version doesn't come close.
There is still a slight hump in the soft tissue there (which looks excessive anyway) and the tips of the neural spines definitely form a hump. But the centra form a straight line. If they were restored as per Janensch's engravings (and dorsals D3 and D4 are not crushed, so there's no need to "straighten" them out) then D3 and everything in front of it would form a steeper angle and less hump without needing such deep nuchal muscles.
Note that D3 and D4 show almost no crushing in the centrum so the articulation angle even at Osteological Neutral Pose still results in an upward tilt of D3, which makes it easier for D2 and D1 to arch up by fewer degrees and still support a vertical neck, with a minimum of strain or flexion on any one joint, far less than in either of Greg Paul's versions or the updated Berlin mount. Take that, Kent Stevens.
So yes, I will be revising my interpretation pretty heavily. Giraffatitan may turn out to be a bit of a sail-back... in the same sense as Acrocanthosaurus.
Stay tuned for more updates, Giraffatitan's dorsals aren't the only weird thing about this beast.
Janensch, W. 1950a. Die Skelettrekonstruktion von Brachiosaurus brancai. Palaeontographica, Supplement 7 (I, 3):97-103.
Janensch, W. 1950c. Die Wirbelsäule von Brachiosaurus brancai. Palaeontographica, Supplement 7 (I, 3):27-93.
Paul, G.S. (1988). "The brachiosaur giants of the Morrison and Tendaguru with a description of a new subgenus, Giraffatitan, and a comparison of the world's largest dinosaurs". Hunteria, 2(3): 1–14.
Paul, G.S. (2010). The Princeton Field Guide to Dinosaurs. Princeton, NJ: Princeton University Press.
Taylor, M.P. (2009). "A Re-evaluation of Brachiosaurus altithorax Riggs 1903 (Dinosauria, Sauropod) and its generic separation from Giraffatitan brancai (Janensh 1914)." Journal of Vertebrate Paleontology, 29(3): 787-806.
They just don't seem believable to me.
While more Forgotten Giants articles are in progress, let's take a look at the odds and ends that often turn up in the more interesting corners of paleontology.
Every once in a while we see something that's mysterious, bizarre, or just unknown, and yet keeps popping up on the internet. And yet it's good enough to warrant a description, or at least a nickname. And many of you, I am in no doubt, fancy yourselves true experts on dinosaurs after having seen just a few episodes of Primeval or the "Walking With" series. But perhaps some of you, seeking earnestly after knowledge, truly are more than just fanboys or fangirls, and can truly call yourselves walking talking museums. Some of you have corrected Wikipedia's dinosaur pages, and been "de-corrected" - and you knew Wikipedia was wrong.
Think you can test your dino-knowledge against the Paleo King, and come out unscathed with not even one intellectual raptor slash to your mental encyclopedia?
Well then this series is for you.
So here's a real stumper (paleo-bucks on the line here): what do you think this is? Does it have a formal scientific name? What family does it belong in? Or is it still an undescribed curiosity - and what name is it known by anyway?... so without further ado... Name that dinosaur!
Well after a LONG time, the Andesaurus project is finally finished - for a while at least. While the open-access issue has been very important, it's time to get back to what this blog is all about - dinosaur art and the science behind it. And Andesaurus is one of the few titanosaurs often touted as being record-breakers which have never gotten a decent restoration until now. This dinosaur is still pretty obscure though it's been known longer than Argentinosaurus, Paralititan, Sauroposeidon, and most of the other new favorites among giant sauropods. Strange, that this animal is literally the demarcation line at the base of titanosauria, universally acknowledged (though not necessarily correctly) as the most basal true titanosaur, extensively used as a key phylogenetic reference taxon in all sorts of papers, every paleontologist studying sauropods knows about it, and yet it's so little known in the public.
Oh, and another thing. It's BIG.
Well maybe not that big. One of the first things you notice about Andesaurus (assuming one of those rare times when you do come across it) is that it's a titanosaur from Argentina. The second thing you notice is that like some other, far more famous titanosaurs from Argentina, its length is listed as over 30m or 100ft in those few books that actually bother to mention it (the only mass-published "layman's author" who seems to give it any attention is Dougal Dixon, in The Illustrated Encyclopedia of Dinosaurs). Andesaurus should be famous, then, if for no other reason than its size - any titanosaur a hundred feet long is pretty high up in the running for both longest and heaviest dinosaur. But don't hold your breath - this is all WRONG.
That's right, you heard me. DEAD wrong. Andesaurus isn't 100 feet long. Not even close. That length has been repeated in many places, Wikipedia among them (at least a few months ago). I don't know how many people have actually read the scientific literature on Andesaurus (which now includes the description paper, Calvo & Bonaparte 1991; the titanosaur comparative anatomy paper Salgado et. al. 1997; and an extensive redescription, Mannion & Calvo, 2011). And the number of people who have actually seen and measured the fossils, I could probably count on my hand. The dorsal vertebrae (what's known of them anyway) are absolutely dwarfed by those of Argentinosaurus - a bit odd for two creatures that were supposedly around the same size. Even plain old Brachiosaurus has bigger dorsals. Andesaurus is a lot smaller than we've been led to believe.
The only photos of this beast that were available online were a couple of grainy mid-90s images...
Andesaurus delgadoi, posterior dorsal and two mid-caudal vertebrae.
Otherwise I had nothing to go on. Until 2010's SVP meeting in Pittsburgh, where by unexpected fortuitous circumstances I came to possess copies of both the description paper and Salgado et. al. 1997 (which actually has drawings of far more of the Andesaurus material). The resulting jumble of odd bone outlines was just enough to start piecing together this beast.
But inevitably some of the outlines were off. So it had to be redone.
Apparently despite all the negative attention and criticism of Elsevier's abuse of wealth and power to stifle scientific knowledge behind steep paywalls, the executives of the corporate academic publishing giant have no regrets and simply have not gotten the message, despite their precious RWA bill being D.O.A. in congress.
David Clark, the incurably arrogant and patronizing senior Vice-President of Elsevier's physical sciences division retorted contemptuously to his company's critics:
There is little merit in throwing away a system that works in favour of one that has not even been developed yet...
This is an outrage - the "system" Clark speaks of only "works" for him and his corporate cronies. For the scientist who is forced to sign away the rights to his research FOR FREE to Elsevier, only to have Elsevier turn around and charge 33% profits on the same article, the system is broken and insanely unfair. And you expect us to believe that access to journal content has never been better, Dave? Don't you mean to say that your shareholders' bottom line has never been better? It's certainly bounced back since 2009, though unless you're a billionaire owning untold scores of their class-A stock, the actual percent return on investment is pretty ho-hum and blue chip-ish.
Furthermore, there IS an alternative system to Elsevier, and it works just fine - plus it's been around for quite a while. Ever heard of PLoS, David? Of course you don't talk about it, because it's the vanguard of the new open-access academic publishing wave of the future. The wave which will bury Elsevier's outdated and feudalistic business model. This business model is indeed fantastically strange: 'Write, edit and review articles for us for free, and we will then sell them back to you at enormous cost'. It should make anyone with a shred of justice and ethics want to vomit all over Elsevier.
If you have not yet signed the petition to boycott and divest from Elsevier over at The Cost of Knowledge, please head on over and do so. I've done it already, and as of today over 8,000 scientists and concerned citizens have done so.
Also be sure to sign the Alliance for Taxpayer Access petition. You pay taxes, you deserve to have access to taxpayer funded research! It's only logical. Don't let corporate publishers steal science. And if you have any news on the hypocrisy of El Serpiente executives, feel free to post it in the comments here. If Elsevier wants to steal the fruits of our labor, lets make it a burning, painful theft they will sorely regret.