Single-segment neck muscles in diplodocids?

November 30, 2023

I don’t remember now when I first noticed bifurcated cervical ribs in apatosaurines. I imagine 2016 at the latest, because on our Sauropocalypse that year Mike and I saw examples at both BYU and Dinosaur Journey. I remember that we specifically set out to document them in CM 3018 on our Carnegie visit in 2019 (story here). (I’m using the term ‘bifurcated’ very loosely here, for any cervical rib that looks like it was getting pulled on in two directions.)

We also noted this cool example in the juvenile brontosaur CM 555. This is the right cervical rib of C7 in lateral view, as it appears in Figure 3 of our new paper. Anterior is to the right, and the dorsal process is the bit making the almost-too-good-to-be-true right angle with the shaft of the rib, near the posterior (left) end of the element.

And here is the same element in a dorso-medial oblique view, in a photo that did not make it into the new paper. Anterior is now to the left, and the capitulum is the fat cylinder of bone sticking out toward us at the lower left. The dorsal process is not perfectly vertical, but sort of ‘leans’ out laterally, which is why it no longer makes a right angle in this corrupted-by-perspective close-up view — it’s pointing not just dorsally, but also laterally, away from the camera.

(This is yet another example of the tyranny of 2d images, and a useful remind that you can’t trust photos of complex bones.)

Anyway, as we discussed last time, that 2019 visit and a bunch of other specimens led us to the new paper that described bifurcated cervical ribs in various apatosaurs but also speculated on the reason for the. Here, again, is Figure 7, which captures the heart of the paper:

Figure 7. Schematic reconstructions of ventral neck musculature in two diplodocid sauropods. A, Apatosaurus louisae holotype CM 3018, cervicals 6 and 7 in left lateral view (reversed), modified from Gilmore (1936, plate 24). B, Diplodocus carnegie holotype CM 84, cervicals 6 and 7 in right lateral view, modified from Hatcher (1901, plate 3). C, mounted skeleton of Apatosaurus louisae in the Carnegie Museum of Natural History, skull and first seven and a half cervical vertebrae in right posterolateral view. Red lines represent the longus colli ventralis muscles, originating on the anterior aspect of one cervical rib and inserting on the shaft of a more anterior vertebra. Blue lines represent the flexor colli lateralis muscles, originating on the anterior aspect of the tuberculum of one vertebra and inserting on the dorsal part of the shaft of a more anterior vertebra. In Apatosaurus the attachment areas are all much larger: in particular, the insertion of the flexor colli lateralis is increased in size by the incipient bifurcation.

Until very recently, I assumed that the longus colli ventralis muscles (red in the image above) spanned more than one pair of vertebrae, and probably the same for flexor colli lateralis (blue in the image above), because that’s how they tend to behave in birds. We only drew them running between adjacent vertebrae to save space, and to make the contrast between Apatosaurus and Diplodocus as stark as possible.

But it’s not impossible that one or both of them were single-segment muscles in apatosaurines. The dorsal processes diverge so sharply away from the cervical shafts that any path longer than one segment is going to be a poor fit for the observed morphology of the cervical ribs — and remember, at this point we have ample evidence that sauropod cervical ribs are ossified tendons, so presumably we can infer the direction of muscle pull from the the angles of the cervical rib bits.

These short muscles would help explain the apomorphically short cervical ribs in apatosaurines and other diplodocoids: the cervical ribs are ossified tendons, and if the muscles they’re embedded in are only one segment long, then the ribs can’t be longer than that.

Tune in next time for exciting news about sauropod neck-muscle mass! Same sauropod-vertebra time, same sauropod-vertebra channel.

 

doi:10.59350/wm7d1-tb814

Posted by Matt Wedel
Filed in Apatosaurus, Brontosaurus, cervical, cervical ribs, diplodocids, papers by SV-POW!sketeers
8 Comments »

What dorsal processes on cervical ribs tell us about neck muscles and their functions

November 28, 2023

Bifurcated and incipiently bifurcated cervical ribs of sauropods. A, Moabosaurus utahensis holotype individual, left cervical rib BYU 14063 (not right as stated by Britt et al. 2017), probably associated with C5, in medial view. B, Dicraeosaurus hansemanni holotype MB.R.2379, right cervical rib 8 in lateral view. Modified from Janensch (1929, fig. 21). C, Brontosaurus parvus CM 555, right cervical rib 7 in lateral view. D, Apatosaurus louisae MWC 1946, cervical vertebra in right lateral view. E, Apatasaurus louisae MWC 5659, cervical vertebra in left lateral view (reversed). All photographs by the authors. Wedel and Taylor (2023: fig. 3).

Here are some cervical ribs of sauropods that show a spectrum of morphologies, from a low dorsal process that makes an obtuse angle with the shaft of the rib in Dicraeosaurus (upper right), to one that makes a right angle in Brontosaurus (center), to a prominent spike of bone in Apatosaurus (bottom left), to a fully bifurcated cervical rib in another vertebra of Apatosaurus (bottom right) and in the turiasaur Moabosaurus (upper left).

Whether they manifest as low bumps or full-on bifurcations, dorsal processes on cervical ribs are odd-looking. But they make intuitive sense. We’ve known for a while now that the cervical ribs of sauropods — like those of birds — are ossified tendons. And from comparisons with crocs and birds, we expect that sauropod cervical ribs had two sets of muscles inserting on them: a lateral set, and a ventral set. They’re the green lines, especially C and E, converging on the cervical rib in this diagram from our 2013 PeerJ paper:

Simplified myology of that sauropod neck, in left lateral view, based primarily on homology with birds, modified from Wedel and Sanders (2002, figure 2). Dashed arrows indicate muscle passing medially behind bone. A, B. Muscles inserting on the epipophyses, shown in red. C, D, E. Muscles inserting on the cervical ribs, shown in green. F, G. Muscles inserting on the neural spine, shown in blue. H. Muscles inserting on the ansa costotransversaria (“cervical rib loop”), shown in brown. Specifically: A. M. longus colli dorsalis. B. M. cervicalis ascendens. C. M. flexor colli lateralis. D. M. flexor colli medialis. E. M. longus colli ventralis. In birds, this muscle originates from the processes carotici, which are absent in the vertebrae of sauropods. F. Mm. intercristales. G. Mm. interspinales. H. Mm. intertransversarii. Vertebrae modified from Gilmore (1936, plate 24). Taylor and Wedel (2013a: fig. 5).

I don’t think we’ve ever shown those muscles in crocs, but they’re there, as you can see in this half-dissected alligator neck:

(Hypaxial neck muscles in crocs aren’t that different from those of birds, just shorter and simpler. It’s in the epaxial neck muscles that theropods and birds diverge wildly from the primitive archosaurian plan. See Figure 11 and related discussion in Taylor and Wedel [2013a].)

If the two sets of muscles converged from different angles, their tendons might ossify separately, at least in part, and that could create the spectrum of dorsal processes and bifurcated cervical ribs shown up top. And that bifurcation would be more likely to manifest if the angle between the converging muscles was wider, as it almost certainly was in apatosaurs. When we were at the Carnegie Museum back in 2019, I doodled this comparison between Diplodocus carnegii (top) and Apatosaurus louisae (middle) and showed it to Mike:

He took one look at the drawing and said, “That’s basically the paper right there.” A cleaner version, using illustrations from Hatcher (1901) and Gilmore (1936) and flipped to face the other way, appears in our new paper as part of Figure 7:

Schematic reconstructions of ventral neck musculature in two diplodocid sauropods. A, Apatosaurus louisae holotype CM 3018, cervicals 6 and 7 in left lateral view (re-versed), modified from Gilmore (1936, plate 24). B, Diplodocus carnegii holotype CM 84, cervicals 6 and 7 in right lateral view, modified from Hatcher (1901, plate 3). C, mounted skeleton of Apatosaurus louisae in the Carnegie Museum of Natural History, skull and first seven and a half cervical vertebrae in right posterolateral view. Red lines represent the longus colli ventralis muscles, originating on the anterior aspect of one cervical rib and inserting on the shaft of a more anterior vertebra. Blue lines represent the flexor colli lateralis muscles, originating on the anterior aspect of the tuberculum of one vertebra and inserting on the dorsal part of the shaft of a more anterior vertebra. In Apatosaurus the attachment areas are all much larger: in particular, the insertion of the flexor colli lateralis is increased in size by the incipient bifurcation. Wedel and Taylor (2023: fig. 7).

If apatosaurs were the only dinosaurs with bifurcated cervical ribs, the conclusion would be almost tautological: giant cervical ribs meant that the neck muscles converged on the cervical rib shafts at wider angles, which would improve the chances of a visible bifurcation in the ossified tendon that is the cervical rib.

Head and neck of mounted Carnotaurus sastrei cast LACM 127704 in right ventrolateral view, showing incipiently bifurcated cervical ribs. Photograph by the authors. Wedel and Taylor (2023: fig. 4).

But the weird thing is, dorsal processes and bifurcated cervical ribs aren’t limited to apatosaurines. As the image up top shows, they’re also present in some dicraeosaurids and turiasaurs, neither of which have giant, low-hanging cervical ribs like those of apatosaurs. And in fact, dorsal processes and bifurcated cervical ribs aren’t even limited to sauropods — the ceratopsian Zhuchengceratops has them, as do several theropods, including Carnotaurus. So what’s going on here?

The serial positions of the cervical ribs with prominent dorsal processes is telling — in every example that we know of, whether sauropod, theropod, or (shudder) ornithischian, the dorsal processes are best-developed in the middle of the neck. That suggests that the divergent muscles were pulling on the cervical ribs hard enough to leave separately-ossifying tendons only at mid-neck, at some distance from both the head and the trunk.

Just a reminder of what Apatosaurus louisae MWC 1946 — same vert as in D of the figure at the top of the post — looks like in ventral view.

It seems these critters were doing some real work with their necks. Ceratopsians and theropods had big heads to hold up and maneuver. Apatosaurs didn’t have big heads, but they had big heavy necks — weirdly, apomorphically, expensively heavy necks — so whatever they were doing, it was probably something important.

References

 

doi:10.59350/ehs80-z5462

Posted by Matt Wedel
Filed in Apatosaurus, Brontosaurus, Carnotaurus, cervical, cervical ribs, dicraeosaurids, diplodocids, dissection, LACM, Moabosaurus, necks, papers by SV-POW!sketeers, stinkin' crocs, stinkin' theropods, turiasaurs
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A simple, old-school paper about bifurcated cervical ribs

November 27, 2023

Everybody(*) knows that the turiasaurian sauropod Moabosaurus has bifurcated cervical ribs: it was all anyone was talking about back when that animal was described (Britt et al. 2017). We’ve featured the best rib here before, and here it is again:

(*) All right, but you know what I mean.

A few years back, Matt started noticing similar (though less extreme) structures in various apatosaurine cervicals, and speculating about what they meant. We thought it would be nice to write this up in a short paper, but that project got quietly left in the long grass, as so many do.

Until this summer.

I’d not seen Matt in the flesh since 2019’s Carnegie Museum visit, thanks to pandemics and whatnot. With Covid finally starting to look less of a threat, my awesome employer Index Data flew us all out to Chicago for a team meeting in August. Since I was going to be in the States anyway, I extended that visit by a week, going via southern California to hang out with Matt before the work meeting.

Here we are on the slopes of Mount Baldy, north of Matt’s stomping ground in Ontario, in the kind of glorious sunshine that you just never get in England.

I don’t think we particularly expected that week to be a fruitful one for work, we just wanted to do fun stuff. But the way it worked out, we stayed up late most nights and did a lot of thinking and writing. So our surprise, we ended up getting two papers completed and submitted that week — and one of them was the study on bifurcated cervical ribs.

Today, that paper is out in VAMP (Vertebrate Anatomy Morphology Palaeontology), and you can read it there (Wedel and Taylor 2023).

I’m fond of this one because it’s pleasingly low-tech and traditional. We looked at some fossils, noticed some interesting features, thought about what they mean, wrote it up, illustrated it with specimen photos and diagrams, and called it done. There is certainly a time and place for phylogenetic analysis, geometric morphometrics, and all the other numerical methods that are increasingly common in vertebrate palaeontology, but I genuinely think it’s important that this kind of work doesn’t squeeze out the more foundational process of looking at, and thinking about, fossils.

Wedel and Taylor 2023:figure 5. Partial neck skeleton of Apatosaurus louisae holotype CM 3018, mounted at the Carnegie Museum in Pittsburgh. C4 (posterior half), 5–7, and 8 (anterior half), in left anteroventrolateral view. White circles highlight the cervical ribs of C6, showing the dorsolaterally directed processes. Photograph by the authors.

We’ll have more to say about this paper, but as noted, you can just go and read it if you like: it’s only ten pages long, beautifully illustrated (if I say it myself) and of course open access.

References

 

doi:10.59350/wm7d1-tb814

Posted by Mike Taylor
Filed in Apatosaurus, Brontosaurus, cervical ribs, papers by SV-POW!sketeers
15 Comments »

Two thoughts on blogging: thought archives, and bullets dodged

November 16, 2023

Brian Engh made this and posted it to FaceBook, writing, “Apropos of nothing here’s Mathew Wedel annihilating borderline parasitic theropods with the Bronto-Ischium of Eternal Retribution — a mythic energy weapon/sacred dinosaur ass-bone discovered by Uncle Jim Kirkland, now stored in Julia McHugh’s lair at Dinosaur Journey Fruita CO.”

I haven’t blogged about blogging in a while. Maybe because blogging already feels distinctly old-fashioned in the broader culture. A lot of the active discussion migrated away a long time ago, to Facebook and Twitter, and then to other social media outlets as each one in turn goes over the enshittification event horizon.

But I continue to think that if you’re an academic, it’s incredibly useful have a blog. I’ve thought this basically forever, but my reasons have changed over time. At first I only thought of a blog as a way to reach others — SV-POW! is a nice soapbox to stand on, occasionally, and it funnels attention toward our papers, which is always nice. Over time I came to realize that a huge part of the value of SV-POW! is as a venue for Mike and me to bat ideas around in. It’s basically our paleo playpen and idea incubator (I wrote a bit about this in my 2018 wrap-up post — already semi-ancient by digital standards!).

More recently I’ve come to realize another part of the value of SV-POW! to me, apart from anyone else on the planet: it’s an archive for my thoughts. If I want to find out what I was thinking about 10 or 15 years ago, I can just go look. And at this point, there is far too much stuff on SV-POW! for either Mike or me to remember it, so we regularly rediscover interesting and occasionally promising observations and ideas while trawling through our own archives.

One of the best pieces of advice I ever got was from Nick Czaplewski, who was a curator at OMNH when I was starting out and for many years thereafter. He told me that you end up writing papers not only to your colleagues but also to your future self, because there’s no way you’re going to remember all the work you’ve done, all the ideas you’ve had, all the hypotheses you’ve tested, and so your published output is going to become a sort of external memory store for your future self. I’ve always found that to be true, and it’s even more true of SV-POW! than it is for any one of my papers, because SV-POW! is vast and ever-evolving.

Created by Stanley Wankel, also from Facebook.

I’ll preface what comes next by acknowledging that I’m speaking from a place of privilege (and not just because I have friends with image-editing software and senses of humor). Broadly, because I’m a cis-het white dude who had a fairly ridiculous string of opportunities come his way (like these and these), but also narrowly in that I’m not trying to make a name for myself right now. I have the freedom to not engage with social media. I never got on Twitter (bullet dodged), and I don’t plan on joining any of the Twitter-alikes (my life is already full, and I already struggle enough with online attention capture). I’m only on Facebook to keep in touch with a few folks I can’t easily reach otherwise, and to promote papers when they come out (because I want to, not because I feel any pressure to). And, frankly, at this point I expect every social media outlet to decay, so my motivation to invest in whatever’s next is minimal.

So, while I’m a definite social media skeptic at this point, I’m alert to the fact that people just coming into the field may want or even need to engage on the new platforms, because they don’t have the option of starting a reasonably popular paleo blog in 2007. But I still think it’s useful to have a blog, precisely because social media platforms decay, and because the conversations that happen on them are so ephemeral. Theoretically you could go back and see what you were saying on Twitter or Facebook 10 years ago, but they don’t make it easy, and why would you? (And good luck doing the same with Google Plus.) So I think if I was starting out at this point, I’d still have a blog, and every time I wrote something substantial or at least interesting on the platform du jour, I’d copy and paste it into a blog post. It might reach a few more folks, or different ones; it might start different conversations; but minimally it would be a way to record my thoughts for my own future self.

I’m curious if anyone else finds that reasoning compelling. It will be interesting to come back in 10 years and see if I still think the same. At least when that time comes, I’ll know where to come to find out what I was thinking in late 2023, and I’ll be able to (provided WordPress doesn’t mysteriously fail between now and then).

My other thought for the day is that SV-POW! has survived in part by dodging a few specific bullets. The first was exhaustion — after blogging weekly for over two years, we decided that we wouldn’t even attempt a weekly schedule anymore, and just blog when we felt like it (2018 was, by intention, an odd year out, and we haven’t repeated that experiment). The second was over-specialization. For the first couple of years we worked a sauropod vertebra into just about every post, and if we blogged about something off-topic, we flagged it as such. Over time the blog evolved into “Mike and Matt yap about stuff”, like how to make your own anatomical preparations, and — most notably — open-access publishing and science communication. I think that’s been crucial for the blog’s survival — Mike and I both chafe at restrictions, even ones we set for ourselves, and it’s nice to able to fire up a WordPress draft and just let the thoughts spill out, whether they have to do with sauropods or not.

Another Stanley Wankel creation. Gareth Monger commented that the band name was ZooZoo Tet, which is instantly, totally, unimpeachably correct.

A third bullet, which I’d nearly forgotten about, was blog-network capture. As I was going back through my Gmail archive (my other digital thought receptacle) in search of the origins of the “Morrison bites” paper (see last post), I ran into discussions with Darren with about Tetrapod Zoology moving from ScienceBlogs to the Scientific American Blog Network. I had completely forgotten that back when the big professional science-blogging networks were a thing, I had a secret longing that SV-POW! would be invited. But they all either imploded (ScienceBlogs) or became fatally reader-unfriendly (SciAm, at least for TetZoo*), and now I look back and think “Holy crap I’m glad we were never asked.” Because even if those networks didn’t implode or enshittify, they’d have wanted us to blog on time and on topic, and both of those things would have killed SV-POW!

*If you are on SciAm, or read any of their blogs, and like them: great. I’m glad it’s working out for you. It didn’t for the only SciAm blog I cared about.

So really both my points are sides of a single coin: have a digital space of your own to keep your thoughts, even if only for your future self, and don’t tie that space to anything more demanding or ephemeral than a website-hosting service.

 

doi:10.59350/29yxb-qh763

Posted by Matt Wedel
Filed in Apatosaurus, Brian Engh, diplodocids, goofy, ischium, navel blogging, Science communication, stinkin' appendicular elements, stinkin' mammals, stinkin' SV-POW!sketeers
17 Comments »

New paper: theropod bite marks on Morrison sauropod bones

November 14, 2023

 

Distal end of MWC 4011, an ischium of Apatosaurus louisae that got munched on by a large theropod, probably Allosaurus or Ceratosaurus. On display at Dinosaur Journey in Fruita, Colorado.

New paper out today in PeerJ:

Lei R, Tschopp E, Hendrickx C, Wedel MJ, Norell M, Hone DWE. 2023. Bite and tooth marks on sauropod dinosaurs from the Morrison Formation. PeerJ 11:e16327 http://doi.org/10.7717/peerj.16327

This one had a long gestation. The earliest trace I can find of it in my Gmail archive is this bit I sent Dave Hone back in February of 2015:

Sorry to not have gotten around to sending the sauropod bite mark stuff. I still have the note in my phone, I’ll get on it ASAP. 

I have no idea what earlier conversation that was referencing — wherever it happened, my end of it apparently wasn’t in Gmail. I also apparently did not follow through, because on April 26, 2018, Dave wrote to me, “I’m vaguely trying to resurrect a survey of sauropod bite marks,” referencing that 2015 message.

At that point I did actually kick into gear and started sending him photos and refs. Which is how, about a month later, he sent one of kindest messages I’ve ever received:

This is starting to get silly, you’ve already turned up more examples than I’ve managed and you’ve also provided papers and photos too! Bearing that in mind, it seems ridiculous not to formally invite you in on this — are you up for continuing to supply some Morrison sauropod bites?

At that point I was the third on the project, with Dave and Emanuel. Later Mark Norell, Christophe Hendrickx, and Roberto Lei would join us, with Christophe serving as our resident theropod tooth expert, and Roberto in particular doing a lot of the heavy lifting of turning our findings into a paper.

The rest of MWC 4011.

So what’s the upshot? For one, a few good-sized sauropod elements are bitten through, showing that at least some Morrison theropods were capable of inflicting real damage on big bones. So right off the bat we have a survivorship problem: in a collections-based survey like the one, we can only tally bite marks on bones that survived being bitten in good enough shape to be collected and identified as sauropod bones. Bones that were consumed by theropods, or shattered beyond the ability to be preserved, recognized, or collected, are not available to us.* In other words, we can only tally bones in the “Goldilocks zone” of being directly chomped on but not too much — careful bites that stripped meat from a bone without biting in are invisible, and so are bites so violent or forceful that they destroyed the bone. This is sort of like the osteological paradox in paleopathology (see this post), just applied to individual bones instead of individual animals.

*In a field-based study, it’s possible to partially offset this by collecting and analyzing everything, not just the identifiable bits. Julia McHugh and colleagues did exactly that in their “nugget bucket” study (McHugh et al. 2023), an IMHO brilliant follow-up to their papers on theropod feeding traces (Drumheller et al. 2020) and invertebrate feeding traces (McHugh et al. 2020) on dinosaur bones from the Mygatt-Moore Quarry. One reason I’m so happy that Julia is at Dinosaur Journey is that she keeps thinking of interesting stuff to do with that collection.

I’ve argued before that baby sauropods left few bones because most of them either grew up, or — vastly more commonly — got processed into theropod poop. I felt like that quip was coming back to haunt me in this project; I find it perversely difficult to think clearly about evidence that I never get to see!

MWC 861, a pubis of Apatosaurus louisae with an extensively bitten distal end. Definitely from the same quarry as MWC 4011 — the Mygatt-Moore Quarry, in far western Colorado — and possibly from the same individual. Also on display at Dinosaur Journey.

Interestingly, we found zero examples of healed bites on Morrison sauropod bones. So all of the bite marks we found were either from successful predation events, or scavenging. And in fact we didn’t find that many bitten sauropod bones, period. We found 68 Morrison sauropod bones with bite marks, out of the 600 or so that we actively surveyed. That’s about 11%, compared to 14% in later tyrannosaur-dominated faunas (Jacobsen 1998). But also, we found a lot of wear on the teeth of large Morrison theropods, which suggests that they were processing tough stuff, including bones.

We suspect that big Morrison theropods were primarily targeting juvenile and subadult sauropods, and scavenging dead adults when they could get them. We think that partly because younger sauropods must have been more numerous than adults (and maybe vastly more numerous), and partly because almost all predators prefer easy fights to difficult ones. As I wrote back when,

Even assuming that max-sized individuals were around – which may not always have been the case… – the theropods would have to walk right past a whole boatload of smaller, easier targets to get to them, ignoring winnable fights and achievable calories just to roll the dice in the most dangerous possible encounters.

Naturally Dave has explored a lot of these ideas in his previous papers, especially Hone and Rauhut (2010) — this new paper is basically a spiritual successor to that one. Dave has his own blog post up about the new paper, here. 

Allosaurus munching on a dead Galeamopus while a pair of ceratosaurs look on hungrily. Art courtesy of Davide Bonadonna (www.davidebonadonna.it)

Theropods primarily attacking small sauropods would explain the patterns that we see, better than any alternative we can think of. Of course the Morrison covers a lot of space and time, and animals do all kinds of weird stuff if you watch them long enough, including suicidal attacks on much larger prey. But if theropods were preferentially attacking adult sauropods, we’d expect to see at least some healed bite marks from failed attacks, and we’d also expect to see more bite marks, period. Somehow big Morrison theropods were managing to put a lot of wear on their teeth without leaving many tooth-marked sauropod bones behind, which seems like a big mismatch. The best explanation we can think of is that the theropods were accumulating that wear munching on juvenile sauropods (which we thought they were doing anyway), and consuming or destroying their bones in the process (which the theropods were well-equipped to do).

But even if we’re right, there’s a ton we don’t know yet. We struggled to match any of the bite marks that we found to specific theropod taxa. Taphonomy and collector bias are probably both big filters, especially for bones that were bitten through or shattered before fossilization. There are definitely important differences between quarries — for example, Mygatt-Moore has a ton of bitten bones, and the Carnegie Quarry at Dinosaur National Monument has almost none, and we don’t know why.

In sum, there’s a lot to do, with interesting, tractable, as-yet-undone projects surrounding this paper in a quantum fuzz like an electron shell. Hopefully other folks will get out there and start turning those potential projects into real ones.

MWC 4011, once more with feeling. And fiberglass. Photo by Brian Engh.

References

 

doi:10.59350/txkht-ewp95

Posted by Matt Wedel
Filed in Apatosaurus, Davide Bonadonna, diplodocids, ischium, Morrison Formation, papers by SV-POW!sketeers, pubis, stinkin' appendicular elements, stinkin' mammals, stinkin' SV-POW!sketeers, taphonomy
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