Friday phalanges: Megaraptor vs. Saurophaganax
April 19, 2013
Is that your flexor tubercle, Saurophaganax, or are you just hungry to see me?
Up top there is a commercially obtained cast sculpture of a thumb claw of Megaraptor. Down below is an unpainted urethane cast of one of my favorite inanimate objects in the universe: OMNH 780, a thumb claw of Saurophaganax. I dunno how much of the Megaraptor claw is real [none, it turns out, but it's based on a true story]; certainly the cast is faithful enough to record some tool-marks in the rugose part near the base. But I know how much of OMNH 780 is legit, and that is all of it. I would have put in a photo of the actual specimen but irritatingly I forgot to take any during my recent visit, and I didn’t have the Megaraptor claw back then anyway. Hopefully I’ll get back to the OMNH this summer, and then it is ON.
The kaiju-loving fanboys of CarnivoraForum undoubtedly want to know how these two compare. Well, much to my disappointment, the Megaraptor claw is a shade longer (28.7 cm max straight-line distance) than the Saurophaganax claw (26.3 cm). But the Saurophaganax claw is about twice as thick and way more robust, and the flexor tubercle which anchored the tendon that powered the claw’s movement is friggin’ immense. It’s like pitting an NBA forward against an NFL linebacker: one is a little taller, but the other one will pound you like a tent stake.
If anyone’s wondering, these claws are both waaay shorter than those of Therizinosaurus (half a meter and up), which still holds the longest-claws-of-anything-ever title. The problem for fans of excessive violence is that Therizinosaurus probably wasn’t doing terribly exciting things with its claws–grooming its feathers, making veggie kabobs, and scratching its ample behind, most likely.
Mmmmmm…suffering. OM NOM NOM NOM!!
The same was not true for Saurophaganax, which the unbelievers call Allosaurus maximus, a red-blooded all American murder machine with a triple PhD in kicking your ass. When it wasn’t drinking camptosaur blood straight from the jugular, it was eating mud-mired diplodocids butt first while they were still alive. And what about those rumors that Saurophaganax was completely feathered in $100 bills, or that it was the direct linear ancestor of Charles Bronson and Steven McQueen? It’s probably too soon to say, since I just made them up, but I’ll bet your mind is blown nonetheless.
How dangerous was Saurophaganax? Let me put it this way: it’s still dangerous. Thanks to the high concentration of heavy elements in Morrison dinosaur bones, you’re supposed to air out the specimen cabinets before you start working so the radon can escape. Otherwise you might breathe in freakin’ radioactive gas and get cancer (in contrast to some “facts” in the previous paragraph, this is actually true). That’s right, Saurophaganax can kill you, just by lying around in a drawer. After 145 million years, it’s still reaping souls for Hades. By god, that’s giving them what for!
In short, the thumb claw of Saurophaganax is the most impressive instrument of dinosaurian destruction I’ve yet laid eyes on. If you want to see it in context, check out the mounted skeleton at the Oklahoma Museum of Natural History in Norman.
This idiot is going to die.
Night at the Museum: LACM’s Camp Dino
April 8, 2013
Last night London and I spent the night in the Natural History Museum of Los Angeles County (LACM), as part of the Camp Dino overnight adventure. So we got lots of time to roam the exhibit halls when they were–very atypically–almost empty. Above are the museum’s mounted Triceratops–or one of them, anyway–and mounted cast of the Mamenchisaurus hochuanensis holotype, presented in glorious not-stygian-darkness (if you went through the old dino hall, pre-renovation, you know what I mean).
We got there early and had time to roam around the museum grounds in Exposition Park. The darned-near-life-size bronze dinos out front are a minor LA landmark.
The rose garden was already closed, but we walked by anyway, and caught this rainbow in the big fountain.
After we checked in we had a little time to roam the museum on our own. I’ve been meaning to blog about how much I love the renovated dinosaur halls. The bases are cleverly designed to prohibit people touching the skeletons without putting railings or more than minimal glass in the way, and you can walk all the way around the mounted skeletons and look down on them from the mezzanine–none of that People’s Gloriously Efficient Cattle Chute of Compulsory Dinosaur Appreciation business. Signage is discreet and informative, and so are the handful of interactive gizmos. London and I spent a few minutes using a big touch-screen with a slider that controlled continental drift from the Triassic to the present–a nice example of using technology to add value to an exhibit without taking away from the real stuff that’s on display. There are even a few places to sit and just take it all in. That’s pretty much everything I want in a dinosaur hall.
Also, check out the jumbotron on the left in the above photo. It was running a (blessedly) narration-free video on how fossils are found, collected, prepared, mounted, and studied, on about a five-minute loop. Lots of pretty pictures. Including this next one.
There are a couple of levels of perspective distortion going on here, both in the original photo and in my photo of that photo projected on the jumbotron. Still, I feel confident positing that that is one goldurned big ilium. I’m not going to claim it’s the biggest bone I’ve ever seen–that rarely ends well–but sheesh, it’s gotta be pretty freakin’ big. And apparently a brachiosaurid, or close to it. Never mind, it’s almost certainly an upside-down Triceratops skull. Thanks to Adam Yates for the catch. I will now diminish, and go into the West.
Triceratops, Styracosaurus, and Einiosaurus–collect the whole set!
Of course, the centerpiece of the second dinosaur hall–and how great is it that there are two!?–is the T. rex trio: baby, juvenile (out of frame to the right), and subadult. Yes, subadult: the “big” one is not as big as the really big rexes, and from the second floor you can see unfused neural arches in some of the caudal vertebrae (many thanks to Ashley Fragomeni for pointing those out to me on a previous visit).
Awwwww! C’mere, little fella!
Still, this ain’t Vulgar Overstudied Theropod Picture of the Week. Here are some sweet pneumatic diplodocid caudals in the big wall o’ fossils (visible behind Mamenchisaurus in the overhead photo above). The greenish color is legit–in the Dino Lab on the second floor, they’re prepping a bunch of sauropod elements that look like they were carved out of jade.
Sudden violent topic shift, the reason for which will be become clear shortly: London and I have been sculpting weapons of mass predation in our spare time. In some of the photos you may be able to see his necklace, which has a shark tooth he sculpted himself. Here are a couple of allosaur claws I made–more on those another time.
The point is, enthusiasm for DIY fossils is running very high at Casa Wedel, so London’s favorite activity of the evening was molding and casting. Everyone got to make a press mold using a small theropod tooth, a trilobite, or a Velociraptor claw. Most of the kids I overheard opted for the tooth, but London went straight for the claw.
Ready for plaster! Everyone got to pick up their cast at breakfast this morning, with instructions to let them cure until this evening. All went well, so I’ll spare you a photo of this same shape in reverse.
We were split into three tribes of maybe 30-40 people each, and each tribe bedded down in a different hall. The T. rex and Raptor tribes got the North American wildlife halls, but our Triceratops tribe got the African wildlife hall, which as a place to sleep is about 900 times cooler. Someone had already claimed the lions when we got there, so London picked hyenas as our totem animals.
Lights out was at 10:30 PM, and the lights came back on at 7:00 this morning. Breakfast was out from 7:15 to 8:00, and then we had the museum to ourselves until the public came in at 9:30. So I got a lot of uncluttered photos of stuff I don’t usually get to photograph, like this ammonite. Everyone should have one of these.
London’s favorite dino in the museum is Carnotaurus. It’s sufficiently weird that I can respect that choice.
Not that there’s anything wrong with the old standards, especially when they’re presented as cleanly and innovatively as they are here.
Finally, the LACM has a no tripod policy, and if they see you trying to carry one in they will make you take it back to your car. At least during normal business hours. But no one searched my backpack when we went in last night, and I put that sucker to some good use. Including getting my first non-bigfoot picture of the cast Argentinosaurus dorsal. It was a little deja-vu-ey after just spending so much time with the giant Oklahoma Apatosaurus–elements of the two animals really are very comparable in size.
If you’re in the LA area and interested in spending a night at the museum–or at the tar pits!–check out the “Overnight Adventures” page on the museum’s website. Cost is $50 per person for members or $55 for non-members, and worth every penny IMHO. It’s one of those things I wish we’d done years ago.
Going to see the big mounted Alamosaurus next week
March 20, 2013
Next week I’m going to visit the Perot Museum of Nature and Science in Dallas, Texas, to see their big Alamosaurus (these photos were kindly provided by Ron Tykoski of the Perot Museum, with permission to post). See that sweet string of cervical vertebrae in front of the mounted skeleton? A photo of those same vertebrae when they were still in the ground was featured in the post “How big was Alamosaurus?” three and a half years ago. Happily now they are out of the ground, prepped, and on display, and Tony Fiorillo and Ron Tykoski are working on getting them and some other new Alamosaurus material described.
Here’s another view of that mount. You may be wondering, first, how legit is it, and second, how big is it? Happily, I have answers for you. In email messages with permission to cite, Ron Tykoski wrote,
The Alamosaurus skeletal mount by RCI in the photos is based upon scaling the Smithsonian and UT Austin material to match the size of our cervicals here in Dallas. There were enough overlapping parts between the pieces at the three institutions to get the proportions pretty nicely supported.
I ran across your SV-POW thread on ‘How big was Alamosaurus?’ back when you first posted it in ‘09. You ought to be pleased to know that you came remarkably close to the eventual size of the skeleton we wound up with. The full skeleton RCI generated (again, based off scaling to the Dallas verts) is 84ft long, about 16ft at the shoulder (I dropped a tape measure from the 1st dorsal neural spine to the floor during skeleton construction and got 480cm-490cm), and a neck + head of about 25ft. The overall length and neck length were provided by RCI after fabrication and assembly. That shoulder height is a bit suspect though based on the positioning of the pectoral girdle in the mount, relative to the ribcage and vert column. I think the head currently is posed about 25ft or so off the floor, but I can’t verify that (I didn’t get into the scissor-lift to check that at the time). This skeleton actually played a role in determining the size of the hall in which it is installed. We decided early in the planning phase for the building that this skeleton would be the centerpiece for the hall. As a result, the ceilings for this floor had to be made extra-high, and the mid-room support pillars designed out to accommodate the skeleton and still clear all the HVAC, sprinkler heads, and other necessities.
That’s all pretty fantastic–both that we have enough of Alamosaurus to do a pretty rigorous full skeletal mount, and that the beast was legitimately pretty darned big. Ron goes on:
One correction to the story on SV-POW, the Dallas cervical series consists of only 9 verts, not 10. There may have been frags or something that made folks think there was a 10th at the anterior end of the series when first found, but I’ve never seen evidence of it in our collection. This may be supported by the fact that the verts were given letter designations in the field (that we still use), and are identified as verts B through J, from anterior to posterior.
I later learned from Tony Fiorillo that the vertebrae were labelled B through J in the field in case anything anterior to B turned up, but nothing did, so the ‘A’ placeholder went unused. That reminds me of the search in the mid-1800s for the hypothetical planet Vulcan (not the one you’re thinking of) between Mercury and the Sun, which I bring up for no reasons other than that hypothetical planets are cool, and if you’re exploring, it’s worth keeping an open mind about what might yet turn up.
There’s more to say about the size of Alamosaurus–we haven’t even covered the big material described by Fowler and Sullivan (2011) yet–but I’m not going to say a whole lot right now, since I’m going to see the Big Bend material in Dallas in just a few days. Watch this space.
Reference
PeerJ launches today! (and we’re in it!)
February 12, 2013
Apatosaurus lousiae 1/12 scale skeleton in left antero-lateral view, modelled by Phil Platt, assembled and photographed by Brant Bassam. Image courtesy of BrantWorks.com.
Today our paper on sauropod neck anatomy is formally published in PeerJ.
There’s not much new to say about the paper, since we posted it to arXiv last year and told the world about it then (post 1, post 2, post 3). Although a lot more attractive in form, this version is almost identical in content, modulo some changes requested by the PeerJ reviewers, and some changes to the figures to make sure every part of every figure was CC BY or otherwise in the public domain. Many thanks to everyone who gave us permission to use their images, especially Scott Hartman, who is rapidly getting to be the go-to person for this sort of thing just by doing good work and being a nice guy.
The big news, of course, is not the paper but the outlet. We’re excited about PeerJ because it promises to be a game-changer, for lots of reasons. Mike has a nice article in the Guardian today about the thing that is getting the most attention, which is the cost to publish. I blogged about it last fall, when I bought the max bling lifetime membership–for about one-tenth of the OA publication fee for a single article from one of the big barrier-based publishers.
Apatosaurus lousiae 1/12 scale skeleton in left lateral view, modelled by Phil Platt, assembled and photographed by Brant Bassam. Image courtesy of BrantWorks.com.
Then there’s turnaround time: for our paper, a mere 72 days, including both submission day (Dec. 3) and publication day (Feb. 12). My fastest turnaround before this was 73 days for my sauropod nerve paper, but that was from submission to posting of the accepted manuscript, not publication of the final version of record. Prior to that I’d had a couple of papers published within six months of submission, but that was definitely the exception rather than the rule. And sadly, I’ve had several situations now where a paper languished in peer review for six months.
And that brings me to peer review–the real “peer” in PeerJ. When you sign up a lifetime membership, you agree to review one paper a year for them to keep your membership active. Certainly not a crushing amount of work, especially since I’ve been averaging 5 or 6 reviews a year for much less congenial outlets.
I’ve seen this from both sides now, since I was tapped to review a manuscript for PeerJ back in December. The first thing I liked is that they asked for the review back within 10 days. That’s just about right. I can see a thorough review taking three days (not working straight through, obviously, but taking time to carefully read, digest, look stuff up, and compose the review), and a busy academic maybe needing a week to find that kind of time. If one is too busy to get it done within 10 days, better to just be honest, say that, and decline the review. There is certainly no reason to let reviewers have manuscripts for four to six weeks, let alone the three to four months that was standard when I got into this business.
Apatosaurus lousiae 1/12 scale skeleton in dorsal view, modelled by Phil Platt, assembled and photographed by Brant Bassam. Image courtesy of BrantWorks.com.
The second thing I liked is that they gave me the option to sign the review (which is almost always implicitly present, whether reviewers take advantage of it or not), and they gave the authors of the manuscript the option to publish my review alongside the paper. I love that. It means that, for the first time ever*, maybe the time and effort I put into the review will not disappear without a trace after I send it off. (It is astonishingly wasteful that we write these detailed technical critiques and then consign them to never be seen by any but a handful of people.) And it had a salutary effect on my reviewing. I always strive to be thoughtful and constructive in my reviews, but the knowledge that this review might be published for the world to see made me a lot more careful, both in what I said and how I said it. Hopefully, the authors I reviewed for will opt to publish my review, so you will be able to judge for yourself whether I succeeded–I’ll keep you posted on that. UPDATE: Hooray! The paper is out, and it’s a beaut, and the authors did publish the review history, which is excellent. The paper is Schachner et al. (2013), “Pulmonary anatomy in the Nile crocodile and the evolution of unidirectional airflow in Archosauria”, the reviews by Pat O’Connor and myself and the author responses and the editor’s letters are all available by clicking the “Peer review history” link on the sidebar, and you should go read all of it right now.
* There are a bare handful of other outlets that publish reviews alongside papers, but I’ve never been tapped to review for them, so this was my first experience with a peer review that might be published.
Naturally Mike and I took the maximum openness option and had our reviews and all the rest of the paper trail published alongside our paper, and I intend to do this every time from here on out. As far as I’m concerned, the benefits of open peer review massively outweigh those from anonymous peer review. There will always be a few jackasses in the world, and if openness itself doesn’t force better behavior out of them, at least they’ll be easier to identify and route around in an open world. Anyway, to see our reviews, expand ‘Author and article information’ at the top of this page, and click the link in the green box that says, “The authors have chosen to make the review history of this article public.”
One happy result of this will manifest in just a few weeks. Bunny-wrangler and sometime elephant-tracker Brian Kraatz and I co-teach a research capstone course for the MS students at WesternU, and one of the things we cover is peer review. Last year I had to dig up a couple of my reviews that were sufficiently old and anonymous that no harm could come from sharing them with the students, but even so, they only got half the story, because I no longer had the manuscripts and couldn’t have shared them if I had. This year I’ll be able to point the students at PeerJ and say, “Go look. There’s the back-and-forth. That’s how we do this. Now you know.”
Science, process and product alike, out in the open, freely available to the world: that’s why I’m proud to be a member of PeerJ.
(And I haven’t even mentioned the preprint server, or all the thought the PeerJ team put into the graphic design of the papers themselves, or how responsive the production team was in helping us get the finished product just right, or….)
Apatosaurus lousiae 1/12 scale skeleton in left postero-lateral view, modelled by Phil Platt, assembled and photographed by Brant Bassam. Image courtesy of BrantWorks.com.
The pictures in this post have nothing to do with our paper, other than showing off one of the beautiful products of the factors we discuss therein. The images are all borrowed from Brant Bassam’s amazing BrantWorks, which we will definitely be discussing more in the future. Explicit permission to reproduce the images with credit can be found on this page. Thanks, Brant!
UPDATE: Bonus Figure
This special version of Figure 3 from our new paper goes out to Dean, who inspired it with this comment. As Tony Stark said, “It’s like Christmas, only with more…me.” Click to enWedelate.
A selection of Matt Wedels (6’2″ or 1.88m tall) with various long-necked amniotes for scale.
Rapetosaurus is Just Plain Wrong
January 31, 2013
You may remember this:
…which I used to make this:
…and then this:
The middle image is just the skeleton from the top photo cut out from the background and dropped to black using ‘Levels’ in GIMP, with the chevrons scooted up to close the gap imposed by the mounting bar.
The bottom image is the same thing tweaked a bit to repose the skeleton and get rid of some perspective distortion on the limbs. The limb posture is an attempt to reproduce an elephant step cycle from Muybridge.
That neck is wacky. Maybe not as wrong as Omeisaurus, but pretty darned wrong. As I mentioned in the previous Rapetosaurus skeleton post, the cervicals are taller than the dorsals, which is opposite the condition in every other sauropod I’ve seen. All in all, I find the reposed Rapetosaurus disturbingly horse-like. And oddly slender through the torso, dorsoventrally at least. The dorsal ribs look short in these lateral views because they’re mounted at a very odd, laterally-projecting angle that I think is probably not correct. But the ventral body profile still had to meet the distal ends of the pubes and ischia, which really can’t go anywhere without disarticulating the ilia from the sacrum (and cranking the pubes down would only force the distal ends of the ilia up, even closer to the tail–the animal still had to run its digestive and urogenital pipes through there!). So the torso was deeper than these ribs suggest, but it was still not super-deep. Contrast this with Opisthocoelicaudia, where the pubes stick down past the knees–now that was a tubby sauropod. Then again, Alamosaurus has been reconstructed with a similarly compact torso compared to its limbs–see the sketched-in ventral body profile in the skeletal recon from Lehman and Coulson (2002: figure 11).
I intend to post more photos of the mount, including some close-ups and some from different angles, and talk more about how the animal was shaped in life. And hopefully soon, because history has shown that if I don’t strike while the iron is hot, it might be a while before I get back to it. For example, I originally intended this post to follow the last Rapetosaurus skeleton post by about a week. So much for that!
Like everything else we post, these images are CC BY, so feel free to take them and use them. If you use them for the basis of anything cool, like a muscle reconstruction or life restoration, let us know and we’ll probably blog it.
AMNH mounted Apatosaurus with Taylor for scale
September 8, 2012
We’re off to Oxford next week for SVPCA, so things may be quiet around here for a few days. Catch you on the flip side.
Plateosaurus sacra of the AMNH
August 15, 2012
Plateosaurus trossingensis AMNH 6810 sacrum and pelvis in left dorsolateral view
We’ve shown a lot of sauropod sacra around here lately (for example here, here, and here), so here’s a little look back down the tree.
You haven’t heard from me much lately because I’ve been busy teaching anatomy. Still, I get to help people dissect for a living, so I can’t complain.
Further bulletins as events warrant.
Infernal specimens of the AMNH
June 24, 2012
Sometimes you just can’t make this stuff up.
You may recall a story from the Onion Our Dumb Century book, allegedly from 1904, about the skeleton of Satan being discovered in Wyoming. Mike used his occult powers to put together this scan from freely available online sources:
If you scrutinize the above image carefully, you’ll see that ‘Satan’ is an Allosaurus (I’m no theropod booster, but I always thought that was a little harsh on T. rex).
Why am I telling you this? Because last week Mike and I were toiling in the big bone room in the basement of the AMNH when we came across AMNH 666.
It’s an ilium. (Of course it would have to be an appendicular element. Vertebrae are from on high [or dorsal, if you prefer].)
Of Allosaurus!
The stomach-churning color here could be a manifestation of diabolical power, or just what happens when you try to photograph a pink specimen label on a yellow-orange forklift.
After this harrowing encounter, we cleansed our bodies, minds, and souls with street-vendor hot dogs and The Avengers.* That particular mode of exorcism may not be the most effective–I felt distinctly dodgy that evening. But the next day we received illumination at the Altar of Sauropod Awesomeness and were soon back to what we jokingly refer to as normal.
* The best way to see The Avengers is by going up to the observation deck of the Empire State Building shortly beforehand, so big swathes of the Manhattan skyline will still be in your mental RAM during the big final battle. I understand it’s not an option for everyone.
Turtle laminae of the Yale Peabody Museum
June 23, 2012
Here’s a cool skeleton of the South American pleurodire Podocnemis in the Yale Peabody Museum.
What’s that you’re hiding in your neck, Podocnemis?
Laminae! Here’s a closeup:
The laminae run from the transverse processes to the prezygapophyses and the centrum, which I reckon makes them analogues of the PRDLs and ACDLs of sauropods.
As long as I’m posting on Peabody turtles, here’s Archelon. It’s not bad, if you’re into that sort of thing. Which Mike clearly ain’t, but for a good reason, which will be revealed soon.
For more info on vertebral laminae in extant non-dinosaurs, see this post and the lower left paragraph on page 212 of this paper.
Dimensions of the mounted Rapetosaurus skeleton
May 5, 2012
Thanks to the kind offices of the folks at the Field Museum, especially Fossil Vertebrates collection manager Bill Simpson, on Wednesday I got to hop the fence and spend some quality time with FMNH PR 2209, the mounted holotype specimen of Rapetosaurus krausei. I took a tape measure with me, to get some dimensions from the mounted skeleton. Of course I have the detailed descriptive paper (Curry-Rogers 2009), but mounted skeletons are three-dimensional objects and it is often surprisingly difficult to get a sense of a how a skeleton goes together in three dimensions from pictures and measurements of the individual elements. And if these dimensions are not precisely those of the animal in life, because of assumptions made during mounting–concerning, say, cartilage thickness between bones, or the angles of the ribs–at least they’re a starting point for understanding the whole-body proportions of Rapetosaurus.
This is valuable because AFAIK this specimen is the only mounted titanosaur in North America, and maybe the only one outside of South America and China. [UPDATE: Alert commenters pointed out that I forgot about the Opisthocoelicaudia in Warsaw, which is almost entirely real, and the Argentinosaurus in Georgia, which is almost entirely fake.] And because Rapetosaurus is far out, man. ALL of the neural arches are unfused, even in the distal caudals–even the Arundel Astrodon (formerly Pleurocoelus) material has fused arches in the distal caudals (Wedel et al. 2000: fig. 15). So it’s a very young juvenile, but the neck is already more than twice the length of the body. I say ‘already’ because there is pretty good evidence that the cervical vertebrae grew proportionally longer over the course of ontogeny in at least some sauropods (Wedel et al. 2000:368-369). The neck is 336 cm long, and the femora are 69 cm long. If we isometrically scaled this animal up to have a 2-meter femur, the neck would be 10 meters long, without any such ontogenetic telescoping of the vertebrae. The implications of this for possible neck lengths in the supergiant titanosaurs are pretty darned interesting. The vertebrae of Rapetosaurus don’t really look anything like those of Argentinosaurus. Nevertheless, a sauropod with an Argentinosaurus-sized femur (2.5 meters for the largest known) and Rapetosaurus proportions would have a 12-meter neck–again, that’s assuming this very young Rapetosaurus already has adult proportions, when in fact it may be ontogenetically short-necked (now there’s a thought). In Apatosaurus and Camarasaurus, the cervicals grew in proportional length (i.e., relative to diameter) by 30-50% over ontogeny, but that’s starting from tiny baby vertebrae. The Rapetosaurus vertebrae are already very long, proportionally, but it is interesting to consider the possibilities that they might have been even longer in adults, and that that scaling might have been shared with other titanosaurs.
The tail in this mount is oddly short. Only about every third vertebra is real, with the rest sculpted, so the tail length inevitably depends on how many intermediary vertebrae were added. But unless there are a LOT of missing vertebrae, it’s probably not far off. I can tell you that when I first saw the mount I looked at the tail and said, “No way”. But up close, seeing the real vertebrae and the interspersed intermediates, it looked pretty reasonable, in part because the individual caudal vertebrae are proportionally short. This is one of those things where we may just have to wait for more and better material–although that might be a long wait, because this skeleton is already freakin’ gorgeous. For someone who is used to dealing with hideously incomplete and groadily distorted fossils, this Rapetosaurus material is just mouth-wateringly beautiful.
There’s loads more weird stuff to talk about, like how the cervical vertebrae are taller than the dorsals, which is opposite the condition in every other sauropod I’ve gotten to look at, and the shape of the ilium, and the conformation of the rib cage, but those will all have to wait for future posts. This one is already much longer than I intended it to be (standard).
For the curious, here are all of my measurements. Neck length, dorsal length, etc. are lengths of those sections of the column as mounted–that is, including both the vertebrae and the spaces between them. I haven’t compared any of these to the published measurements, these are straight from the tape measure to my notebook to you. I’m giving them in mm, because that’s what I naturally think in, but they’re all rounded to the nearest cm because given my methods–hand-holding a physical tape measure up next to a bone while I crouch contorted under a fragile mounted skeleton–giving measurements to the nearest mm would be illusory precision.
- Skull length: 290
- Neck length: 3360
- Dorsal length: 1210
- Sacrum length: 480
- Tail length: 1720
- Total length of skeleton, snout to tip of tail (sum of above): 7060
- Glenoid height (ground to top of socket): L – 1110 (forefoot off floor by a few cm), R – 1080
- Acetabular height (ground to top of socket): 1320 on both sides
- Max height of body (ground to top of 5th sacral spine): 1630
- Gleno-acetabular distance: L – 1500, R – 1440
- Width across acetabula: 440 between weight-bearing centers, 470 to outer margins of ilia
- With across glenoids (at bottom of scap-coracoid joints): 710
- Femur length: 690 on both sides
- Tib/fib length: 470 on both sides
- Vertical height of foot: L – 90, R – 120 (different poses)
- Humerus length: L – 530, R – 500
- Radius/ulna length (between articular surfaces, not including olecranons): L – 370, R – 360
- Metacarpus length (MT3): 190 on both sides
References
- Curry Rogers, Kristina. 2009. The postcranial osteology of Rapetosaurus krausei (Sauropoda: Titanosauria) from the Late Cretaceous of Madagascar. Journal of Vertebrate Paleontology 29:1046-1086.
- Wedel, Mathew J., Richard L. Cifelli and R. Kent Sanders. 2000. Osteology, paleobiology, and relationships of the sauropod dinosaur Sauroposeidon. Acta Palaeontologica Polonica 45(4): 343-388.
