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.
Sauropod Vertebra Picture of the Week 
December 31, 2017 at 6:51 pm
THAT’S a cervical vert?!?!? Holy jeebus!
It’s also a *very* good demonstration of the “search image” hypothesis for why large fossils were not studied in earnest until much later than fossils shells, teeth, and the like. I would have simply thought it was a small, pock-marked boulder. I doubt anybody before the time of Cuvier would’ve ever registered it as anything else either.
December 31, 2017 at 8:30 pm
You all are naughty and causing problems. ;)
December 31, 2017 at 11:25 pm
Three months and one day, dude. That’s all you had to wait. SMH.
December 31, 2017 at 11:35 pm
I know, I know. Just couldn’t help myself. Plus I didn’t want to telegraph that obviously.
December 31, 2017 at 11:50 pm
Guess we gotta keep people on their toes, yeah? Like my photo of the unscaled-but-possibly-157-meter shark a few posts ago.
December 31, 2017 at 11:52 pm
You know it, bro.
January 1, 2018 at 12:26 am
Just back from Hawaii, and that looks a lot like the air bubbles from within igneous rock …
January 1, 2018 at 12:39 am
Definitely some hot air involved here.
January 1, 2018 at 2:00 am
Wow! That’s just an awesome find!
January 1, 2018 at 2:19 am
Ridiculous. Those are obviously pneumatic spaces within an insanely large skull bone
January 1, 2018 at 1:02 pm
Omg but if 3,6 m this animal could be huge size…. 100 m long ? what the hell,,,,
January 1, 2018 at 7:17 pm
Now that I think about it, could asteroids just be sauropod verts?
January 1, 2018 at 7:18 pm
See Dr. Wedel’s comment above…
January 2, 2018 at 8:20 am
I knew this day would come. A mega-brachiosaur to outclass the OK apatosaurines. Just like B. altithorax outclassed all the mounted apatosaurs of last century. Mega-brachiosaurs, scaly T. rex impressions, and the Tschoppers trend of splitting sauropods not lumping them. Sweet times, are we in the 90s again?
January 2, 2018 at 5:10 pm
Um…better check the previous comments.
January 3, 2018 at 5:17 am
Well I feel stupid…….
January 4, 2018 at 3:28 pm
No! So not funny! I mean, I can really appreciate a good joke but not about (new, record) gigapods.
I can still feel the pain of disappointment by the Stromer-Aegyptosaurus joke:
https://svpow.com/2008/04/01/aegyptosaurus-lost/
January 9, 2018 at 10:52 pm
I suspect you both suffer from a rare form of pareidolia which, rather than human faces, you two see sauropod vertebrae in places they don’t exist. :-D
January 10, 2018 at 2:24 am
Just reading this now – wow! Same thoughts, look at how much now-empty space among the bone matrix! The rock to your right (left edge of picture) looks similar in that regard, is there any (other?) sign of anything articulated with it? And just exactly how DO you go about excavating something that bloody big?! (The last is intended to be rhetorical, it’s been done and I bet I can find someone’s time-lapse video if I were awake)
Wow! Who found it? Without the blog context, I’d’ve thought it an unusually large-pored lava rock, though looking again, impossibly so and probably not in a volcanic context. But I assume you were given the location? (I’m not asking where, though it would be neat to see in person, but that’ll be a while for me)
January 10, 2018 at 2:32 am
Glad I read the comments after posting, rather than not at all. Took me 3 times through to get it, though. Sigh. Ha ha. Sigh. Agree with the other disappointed people.
January 10, 2018 at 2:42 am
I see that would probably at least triple, probably quadruple, the record length. Oh well. I guess volcanic rocks had much larger vesicles than I’d realized. Yeah, another 3 months and a day would have been nice!
January 10, 2018 at 5:07 am
That’s wind-eroded sandstone, not volcanic in origin. We have _tons_ of pictures of weird sandstone from that trip, and we’ll probably dole out more of it in due time.
April 20, 2018 at 1:53 pm
I just couldn’t believe my eyes. Have you extrapolated the approximate length of the whole animal? I’ve tried, but I am getting some outstanding numbers.
April 21, 2018 at 5:19 pm
Oh, Berislav, I’m so sorry. This post was a joke.
April 23, 2018 at 2:40 pm
no, no, no, Mike. You got it all wrong. It is clearly the cervical of Amphicoelias fragillimus Cope 1878. You just can’t see the bifurcated neural spine in this profile. :-)
April 23, 2018 at 2:43 pm
It’s a bit too big to be that.
April 23, 2018 at 2:45 pm
Not necessarily. It was a giant bull that never found its mate because she was in Colorado, i.e., different specimens
April 23, 2018 at 8:55 pm
Sounds legit.
May 2, 2018 at 1:06 pm
It seemed strange, However, you missed April the 1st for posting this. Didn’t you?
May 2, 2018 at 1:22 pm
Didn’t want to make it too obvious.
May 4, 2018 at 5:47 am
Mike, it would have been obvious if it weren’t for your comments accompanying the photographs and the outline drawing. I don’t see the point of posting that outside the April 1st. I’ll give you an example. An image I have posted on April 1st a few years ago: A reconstruction of a foot of an enormous Iggy whose footprints “I have found”. Would you have bought that if you had missed seeing the date? Please, click the link to see the image.
https://dinosaurtracker.deviantart.com/art/Huge-iggy-zs-kylie-743372992
May 4, 2018 at 8:14 am
Well, Berislav, I am sorry that you didn’t see the point of this post.
May 4, 2018 at 8:27 am
Well, all of your other posts are very interesting and informative and I enjoy reading them.