All the SV-POW! videos, and other stuff on the sidebar
June 25, 2024

BYU 11505, a caudal vertebra of a diplodocid from Dry Mesa, in posteroventral view. Note the paired pneumatic foramina on the ventral surface of the centrum.
If you want to find the paleontology and anatomy videos that Mike and I have done (plus one video about open access), they have their own sidebar page now, for your convenience and for our own. It’s, uh, just to the right of where your eyes are pointing right now. You know what, I’m sure you’ve got this.
Make a better living with extensively curated sidebar pages
In fact, we’ve added a few sidebar pages in the comparatively recent past (for a blog in its 17th year). In addition to the video page, we now have some project-specific pages, namely Mike’s Supersaurus, Ultrasaurus and Dystylosaurus in the 21st Century and Mike’s open projects pages, and my own Neural canal projects page. For now the global list of Haplocanthosaurus posts lives on the page for the Wedel et al. (2021) Haplocanthosaurus neural canal paper, but I imagine it’s only a matter of time until I add a page just to track all my business with Haplocanthosaurus. Also, ugh, I still have a few papers that I’ve blogged about, but which don’t have pages, and are therefore just that much harder to find.
And of course we still have all the old standbys: Tutorials, Things To Make and Do, The Shiny Digital Future, and so on.
It might seem kinda dumb to do a post alerting people to stuff that they can find for themselves, but the whole point of having the sidebar pages is that SV-POW! has gotten to be rather unmanageably vast, and anything that helps us — or even you! — get to the right posts quickly is a welcome assist.
The photo up top has nothing to do with any of this, I just thought it would be a fun way to meet our titular mandate.
My friend and frequent collaborator (one, two, three) Tito Aureliano invited me to give a talk on his YouTube channel, I suggested pneumaticity and gigantism, and here we are. There’s a decently lengthy Q&A, moderated by Tito, after the talk itself. Hilariously — and kindly — one of the commenters pointed out that I hadn’t explicitly answered the titular question in the talk, so I took a stab at it in the Q&A. I come on about 1:40, the talk starts about 5:20, and the Q&A starts at 1:24:30.
If you’ve seen any of my pneumaticity talks since, er, I gave my dissertation finishing talk in 2007, you’ve seen at least a few slides of this. But you won’t have seen all of them before, because a good number of them didn’t exist; this is sort of a Frankenstein stitched together from previous talks, new observations, and trying to think about the future. In particular, almost my entire 2012 SVPCA talk is crammed in near the end.
If in the talk I sound less certain about some things than I have in the past, that’s accurate. In the past few years I feel like I’ve accumulated a lot of interesting pieces (most of my post-2020 papers), and I’m in quest of a new synthetic foundation for my work (e.g., Taylor and Wedel 2021, this post), but I’ve also Seen Things that have rocked my certainty about my own level of understanding (e.g., Aureliano et al. 2023, this post). I’m cool with that. I think that whatever comprehension of pneumaticity I’m questing toward is going to have to emerge inductively from all the pieces, new and old, that I and others are producing. That’s an exciting prospect, and I’m having enough fun with the individual Legos that I’m in no tearing rush to guess what the final product will look like.
Many thanks to Tito for the invitation. After having just given a big talk that was a little speculative and a little outside my wheelhouse, it was nice to come back to home base, but hopefully still give people some useful things to take away. Time will tell.

BYU 12613, a very posterior cervical (probably C14 or C15) of a diplodocine sauropod, probably Kaatedocus or Diplodocus, from Dry Mesa, original fossil and 50% scale 3D print. The real bone has a mid-height centrum length of 270mm, compared to 642mm for C14 of D. carnegii.
I intended for the next post to be a follow-up on the new paper describing the Dry Mesa Haplocanthosaurus, as I hinted/promised in the last post. But that post is still gestating, there’s a lot of other cool stuff happening right now, and I don’t want to put off posting about it and risk never getting around to it.
Pneumatic diverticula in birds on the cover of Nature
I’m probably getting to be a crank on the subject of how pneumatic diverticula in birds are so grotesquely understudied. F’rinstance: the poultry industry is a $77 billion per year concern in the US alone, and the lung/air-sac system and its diverticula are a route for potentially lethal infections (which also affected sauropods), so you’d think we’d have the diverticular system of chickens and turkeys completely mapped, and its development fully charted. But we don’t!
See? Crank!
Anyway, Emma Schachner — who’s been doing awesome work in the arena of reptile and bird respiration for years (see here, here, and the comment thread here, for starters) — and colleagues just put bird diverticula on the map in a most spectacular fashion, with a cover article in Nature.
The short, short version is that Schachner et al. surveyed the sub-pectoral diverticulum (SPD) in 68 species of birds (in 42 families and 25 orders), and found that it was present in all soaring taxa, where it evolved at least 7 times, but absent in non-soarers. Furthermore, the SPD is in the right place to improve the mechanical advantage of the pectoralis muscles, which have a different architecture in soaring taxa, one that appears to be adapted in concert with the SPD for the particular demands of soaring flight. Schachner et al. illustrate their findings with just a ton of cool dissection photos, CT slices, and 3D reconstructions, in both the paper proper and the SI. Happily, the paper is a proper publication, 6 pages long and with plenty of detail, and not cut down to a glorified abstract.
Many things make me happy about this paper: the references to Owen (1836) and Strasser (1877), who independently suggested that the diverticula of birds might positively affect their flight dynamics; a strong team of authors taking a largely neglected anatomical system and spinning it into scientific gold; and the participation of my friends Raul Diaz and Jessie Atterholt. Together with our 2022 paper in the Anatomical Record, this is Jessie’s second taxonomically broad survey of a previously under-documented diverticular system in birds in just over two years, which is a heck of a (ahem) feather in her cap.
Given that birds have a whole internal zoo of diverticula that go between their muscles, among their viscera, under their skin, and into their bones — almost all of which are known from a bare handful of documented examples — I’m sure that there are many, many more exciting discoveries to make in this space. As Schachner et al. put it, “The discovery of a mechanical role for the respiratory system in avian locomotion underscores the functional complexity and heterogeneity of this organ system, and suggests that pulmonary diverticula are likely to have other undiscovered secondary functions.”
(If you’re thinking of not working on pneumaticity because some people are already working on [their own little corners of] it, perish the thought. At the current rate it could take decades just to document where the diverticula are and what they look like, let alone their functional implications. If the world can accommodate a new theropod phylogeny every couple of weeks, it can stand a lot more work on pneumaticity in birds and other dinos.)
Video: all the Oklahoma dinosaurs
My longtime friend and mentor, Kyle Davies, is the head preparator at the Sam Noble Oklahoma Museum of Natural History in Norman, where I did my undergrad and master’s work. Kyle is a phenomenally skilled morphologist, and if he needs something for education or exhibit that he can’t otherwise get hold of, he’ll just sculpt it himself — we’ve featured his work before (here and here). He recently gave a brown-bag lunch talk reviewing all of Oklahoma’s dinosaurs, and it’s just been posted to YouTube. Go have fun.
More travel and collections pics real soon

Luke Horton helping me get a shot of the right side of the ‘Jimbo’ Supersaurus dorsal on display at the Tate Geological Museum in Casper. The left side of this cast is visible in this post.
I just got back from a crazy-awesome research trip that I structured around the Tate Geological Museum’s 2024 summer conference. I got to spend time seeing the exhibits and working in the collections of a host of institutions, including:
- the University of Wyoming Geological Museum in Laramie,
- the Tate Museum in Casper,
- the Wyoming Dinosaur Center in Thermopolis,
- the Natural History Museum of Utah in Salt Lake City,
- the Museum of Ancient Life in Lehi, Utah,
- and — chronologically last but certainly not least — the BYU Museum of Paleontology in Provo.
At BYU I got three days to roam through the collections with Colin Boisvert, Brian Curtice, Ray Wilhite, and Gunnar Bivens. It was easily one of the most productive research trips I’ve ever had, rivaled only by the 2016 Sauropocalypse with Mike. In fact, we’d hoped that Mike would get to join me for part or all of the trip, but as luck would have it he had day job trips of his own in the same time frame. He did at least get to see the mounted cast of D. carnegii in Vienna, which he was keen to see.
This trip also had this in common with the 2016 Sauropocalypse: everywhere I went, curators, collections managers, and students were unfailingly kind, hospitable, and generous with their time and knowledge. Thanks in particular to Julian Diepenbrock, Laura Vietti, and Whitney Worrell in Laramie; JP Cavigelli, Dalene Hodnett, Shaedon Kennedy, and Rachel Stevens in Casper; Tom Moncrieffe and all the staff in Thermopolis; Carrie Levitt-Bussian at the NHMU; Rick Hunter and April Hullinger in Lehi; and Rod Scheetz, Colin Boisvert, Jacob Frewin, and Isaac Wilson at BYU.
A special thanks to Luke Horton, who is currently an undergrad at Texas A&M. He made it out to Casper for the Tate conference and field trips, and he stuck around for a day afterward to assist me in collections. Given his passion for paleontology and his work ethic, I expect you’ll be hearing more about Luke in the not-too-distant future.
The upshot of all of this is that I have roughly a million cool things to post from the trip, many of which I’ll no doubt forget about or never get around to, but I will make an effort to convert trip photos into blog fuel this summer. The photo up top is the first snowball in what will hopefully become an avalanche. At BYU I was cruising down one of the aisles of sauropod vertebrae (yes, at BYU they have literally aisles of sauropod vertebrae — heaven!) and I did a double-take: it was my old friend BYU 12613! Mike and I figured that vert in our 2013 neural spine bifurcation paper, and I’d used the 50% scale 3D print in my Dolly video. I’d brought the print along on the trip as a handy visual and tactile aid for introducing people to sauropod cervical morphology, and I’d passed it around for show-and-tell during my Tate keynote talk. I couldn’t resist putting the real fossil and the 3D print together for a photo op. Here’s one more for the road, in postero-dorsal view this time:
In addition to blog posts, you’ll be seeing photos from this trip in presentations and papers as soon as it can be decently arranged. Stay tuned!
References
- Atterholt, Jessie, and Wedel, Mathew J. 2022. A computed tomography-based survey of paramedullary diverticula in extant Aves. The Anatomical Record 306(1): 29-50. https://doi.org/10.1002/ar.24923
- Schachner, Emma R., Andrew J. Moore, Aracely Martinez, Raul E. Diaz Jr, M. Scott Echols, Jessie Atterholt, Roger W. P. Kissane, Brandon P. Hedrick, & Karl T. Bates. 2024. The respiratory system influences flight mechanics in soaring birds. Nature 630: 671-676. (link)
- Wedel, M.J. 2024. The sauropod heresies: evolutionary ratchets, the taphonomic event horizon, and all the evidence we cannot see. The Jurassic: Death, Diversity, and Dinosaurs, 28th Annual Tate Conference abstract book: 35-38.
- Wedel, Mathew J., and Michael P. Taylor. 2013. Neural spine bifurcation in sauropod dinosaurs of the Morrison Formation: ontogenetic and phylogenetic implications. Palarch’s Journal of Vertebrate Palaeontology 10(1):1-34. ISSN 1567-2158.
New paper out today on the Dry Mesa Haplocanthosaurus
June 18, 2024

Skeletal inventory of the Haplocanthosaurus bones found at Dry Mesa Dinosaur Quarry. Boisvert et al. (2024: fig. 2).
This morning saw the publication of my new paper with Colin Boisvert, Brian Curtice, and Ray Wilhite:
Colin’s nexus of sauroponderous awesomeness
First off, big congratulations to Colin, who is having a banner season. On May 22 he gave his Masters thesis defense talk at BYU, on digital and physical articulation of the neck of BYU 18531, the “big pink apatosaur” from the Mill Canyon Quarry. You’ve seen that specimen in a few of our previous posts (notably here, midway down here, lurking in the background here), and Colin and his advisor, Brooks Britt, kindly gave Mike and me permission to publish some photos of one of the vertebrae in our recent cervical rib paper (Wedel and Taylor 2023).
As luck would have it, Colin is at NAPC this week, and this very morning he gave back-to-back talks. His second talk was a shorter version of his thesis defense talk, and his first talk was on (drumroll) Haplocanthosaurus: “Eleven specimens from ten locales in eight collections across three states, the diversity of known Haplocanthosaurus specimens in the Morrison Formation”, with Brian and Ray and me as coauthors. By sheer dumb luck, our paper dropped literally an hour or two before Colin’s Haplo talk, so when he got to the Dry Mesa individual he was able to plug the hot-off-the-presses new publication. That timing could not have been more perfect. Incidentally, the NAPC program and abstract book are both free downloads at this page; Colin’s abstracts are back-to-back on pages 125 and 126 (by internal numbering, pp. 135-136 of the PDF).
It’s an especially momentous day because this is Colin’s first peer-reviewed journal publication — or, more accurately, of the several things he’s working on, this was the first to make it across the finish line. You’ll be hearing a lot more from Colin in the near future. (As Brian Curtice has pointed out, when someone has “vert” right in their name, we should be primed to expect great things. [NB: Colin’s last name is pronounced “bwa-VAIR” not “BOW-iss-vert”; replacing ‘vert’ with ‘air’ is, of course, the most sauropod-appropriate thing ever.]) We shall watch his career with great interest.
Enough back-patting, what’s this paper about anyway?
The quick version is that this paper is the longer, more complete, and more paleobiologically-informed version of our short paper for the 14th Symposium on Mesozoic Terrestrial Ecosystems and Biota (MTE14) last June (Curtice et al. 2023 and this post). As soon as we’d presented that, we realized that we needed to properly describe and illustrate every element of the Dry Mesa Haplo. Colin took point, and a year later, here we are.
So what do we have of this beast? Seven dorsal vertebrae and a right tibia, all found reasonably close together in a little pocket in the vast expanse of Dry Mesa Dinosaur Quarry. The vertebrae are obviously referable to Haplocanthosaurus because of their dorsally-oriented transverse processes, which instantly mark out Haplo from all the other known Morrison sauropods (note the caveat and hold that thought for the next a future post). The tibia is also referable to Haplo based on its chunkiness and the flared distal end, and it’s the right size to be from the same individual as the vertebrae.

BYU 17531, a block of three anterior dorsal vertebrae preserved in articulation. The vertebrae are shown in right lateral (a), anterior (b), posterior (c), ventral (d), and dorsolateral (e) views. Scale bars are 10 cm. dp, diapophysis; hyp, hyposphene; nsp, neural spine; pcdl, posterior centrodiapophyseal lamina; pf, lateral pneumatic fossa; podl, postzygodiapophyseal lamina; poz, postzygapophysis; pp, parapophysis; prz, prezygapophysis; spol, spinopostzygapophyseal lamina. Boisvert et al. (2024: fig. 3).
Our best bit is BYU 17531, a series of 3 articulated anterior dorsal vertebrae. They record the migration of the parapophysis from low on the centrum up onto the neural arch, which is always nice to see. The block of three is a little sheared left-to-right, as shown in part D of the above figure. I’d love to get them CT scanned to investigate the articulations between the zygapophyses and the centra, a desire that only manifested as I was writing this post, looked again at the figure, and thought, “Oh, hey, intervertebral joint spacing!”

BYU 17530, a posterior dorsal vertebra. The vertebra is shown in anterior (a), posterior (b), left lateral (c), right lateral (d), dorsal (e), and ventral (f ) views. Scale bars are 10 cm. cprl, centroprezygapophyseal lamina; dp, diapophysis; hpn, hypantrum; hyp, hyposphene; lat. cpol, lateral centropostzygapophyseal lamina; nc, neural canal; pcdl, posterior centrodiapophyseal lamina; pf, pneumatic fossa; poz, postzygaphopysis; pp, parapophysis; prz, prezygapophysis; spdl, spinodiaapophyseal lamina; spol, spinopostzygapophyseal lamina; sprl, spinoprezygapophyseal lamina. Boisvert et al. (2024: fig. 6).
We also have four more posterior dorsals. I put them side-by-side in the skeletal inventory figure, but that was mostly out of laziness parsimony; most are too poorly preserved for us to get a firm fix on their serial position. We know that the best preserved of the bunch, BYU 17530, must be a pretty posterior dorsal, because the transverse processes are skinny and the neural spine is flared laterally (more anterior dorsals have dorsoventrally thicker transverse processes and narrower neural spines — see Hatcher 1903: plate 1, crucial bits of which are replicated at the top of this image).

Dorsal 12 of CM 572 in anterior (a), posterior (b) and right lateral (c) views, compared to BYU 17530, the best preserved posterior dorsal vertebra in anterior (d), posterior (e), and right lateral (f) views. Scale bar is 10 cm. Boisvert et al. (2024: fig. 7).
BYU 17530 is a pretty good match for D12 in CM 572, as shown in our figure 7. The top half of the anterior centrum face of the BYU vert is blown off, so we can see the large pneumatic fossae in the centrum, as well as the narrow median septum of bone that separates them. But that’s about the only significant damage, so I call BYU 17530 the “good dorsal”.

BYU 17689, a posterior dorsal vertebra. The vertebra is shown in anterior (a), posterior (b), left lateral (c), right lateral (d), dorsal (e), and ventral (f) views. Scale bars are 10 cm. cprl, centroprezygapophyseal lamina; dp, diapophysis; hpn, hypantrum; hyp, hyposphene; lat. cpol, lateral centropostzygapophyseal lamina; nc, neural canal; pcdl, posterior centrodiapophyseal lamina; pf, pneumatic fossa; poz, postzygaphopysis; pp, parapophysis; prz, prezygapophysis; spdl, spinodiapophyseal lamina; spol, spinopostzygapophyseal lamina; sprl, spinoprezygapophyseal lamina. Boisvert et al. (2024: fig. 8).
At the other end of the preservation quality spectrum, BYU 17689 is just happy to be here. The very tall neural arch pedicles and vaulted space over the neural canal are pure Haplo, and it’s from the same part of the quarry, same preservation, and right size to belong to our critter, but whew, that is a shard of excellence* for sure.
* For newer readers, sauropod vertebrae are never “pieces of crap”, no matter how badly broken. Rather, they are “shards of excellence”. The same idea could be extended to other clades. I can envision referring to poorly-preserved pneumatic vertebrae of theropods as “fragments of adequacy”. Broken ornithopod vertebrae are the “morning eye-boogers of Time”.

Haplocanthosaurus and Camarasaurus tibiae compared. USNM V 4275, a left Haplocanthosaurus tibia and astragalus (a), compared to BYU 12865, a right tibia (b), and YPM 5861, a left Camarasaurus tibia (c). Scale bar is 20 cm. The yellow line on USNM V 4275 represents the transition from tibia to astragalus. The cnemial crests for the two Haplocanthosaurus tibiae are incomplete. ap, anterior process; cc, cnemial crest; pp, posterior process. Boisvert et al. (2024: fig. 10).
The tibia, BYU 12865, is a little crushed and has some mid-shaft damage, but the flaring distal end is in good shape, enough to show that the bone is consistent with Haplocanthosaurus morphology.
What’s it all mean?
Why do we care about this critter?
First, as the title of Colin’s NAPC talk makes clear, there aren’t that many Haplos in the world — 11 to date, compared to over 200 for all the camarasaurs in the Morrison — so each new one is nice to have. In particular, the Dry Mesa Haplo has only the second set of articulated anterior dorsals for the genus, and the tibia helped us figure some things out regarding other Haplo specimens; more on that another time, perhaps.
Second, as we punched up in our MTE14 paper last year, this Haplocanthosaurus means that a minimum of six sauropod genera were present at Dry Mesa, making it the most diverse sauropod quarry in the world. I already wrote a whole post about that (link), so I’m not going to belabor it here, but it bears thinking about. Maybe six isn’t an unusual number of sauropods in an ecosystem, it just takes a quarry with 4000+ bones to capture them all.
Third, a little push from our editor at the Anatomical Record got us thinking about why Haplocanthosaurus dorsal vertebrae are so distinctive. More on that in the next a future post.
For more posts on Haplocanthosaurus, see the running list on this page (link).
References
- Boisvert, Colin, Curtice, Brian, Wedel, Mathew, & Wilhite, Ray. 2024. Description of a new specimen of Haplocanthosaurus from the Dry Mesa Dinosaur Quarry. The Anatomical Record, 1–19. http://doi.org/10.1002/ar.25520
- Curtice, B., Wedel, M.J., Wilhite, D.R., and Boisvert, C. 2023. New material of Haplocanthosaurus (Hatcher 1903) from the Dry Mesa Dinosaur Quarry and a comment on sauropod diversity. In Hunt-Foster, R.K., Kirkland, J.I., and Loewen, M.A. (eds), 14th Symposium on Mesozoic Terrestrial Ecosystems and Biota. The Anatomical Record 306(S1):79-81.
- Wedel, Mathew J., and Michael P. Taylor. 2023. The biomechanical significance of bifurcated cervical ribs in apatosaurine sauropods. VAMP (Vertebrate Anatomy Morphology Palaeontology) 11:91-100. doi: 10.18435/vamp29394
Fossils of Jimbo the Supersaurus on exhibit
June 14, 2024

To answer Mike’s question from the last post, here’s a nice dorsal of Jimbo. All the material’s from the same quarry and has consistent preservation, and this dorsal is a monster. I didn’t try to measure it through the glass.
Hey guess what? It’s gonna be another really short photo post. Here are some pix of the Jimbo material on display at the Wyoming Dinosaur Center. Many thanks to Tom Moncrieffe of the WDC for taking a good chunk of his day to show me around.

Two partial cervical vertebrae, with part of a little one in between them, and a sectioned rib up on the shelf. I didn’t try to measure these through the glass either, but I’d estimate that each of the cervical centra is a meter and change in length, and both were a few cm longer when complete.

I don’t know if this pneumatic dorsal rib was too big, too dense, or too expensive to CT scan, but Dave Lovelace and colleagues did the next best thing: they sectioned it with a big rock saw. Pretty cool if you ask me.

Next cabinet going around clockwise has these dorsal vertebrae and a couple of broken neural spine tops. The vertebra on the left is the one shown in lateral view at the top of this post.

A tibia and a fibula. This is where it gets a little weird. I measured the other fibula, not on display, as being 116cm long. That sounds big, but it’s only a few cm larger than the fibulae of CM 3018 or AMNH 6341. So either Jimbo was unusually short-legged for the size of its vertebrae, or these limb bones belong to a different individual.

And the rest of the caudals in that cabinet, a selection from different spots down the tail, with chevrons.
I have roughly 2376 interesting things I want to blog about, but my head is already about to split open with all the fascinating sauropod anatomy I’ve seen in the past few days, and I’m staring down the barrel of three more days of this. Stay tuned!
Quick pix of ‘Jimbo’, the Wyoming Supersaurus
June 13, 2024
Another quick photo post from the road. The Tate Museum has a quality in common with the Oxford Museum of Natural History, where the guiding philosophy seems to have been, “Let’s put one of every interesting thing in the world in one big room.” Tucked into a corner is this small assemblage of cast bits of ‘Jimbo’, the Wyoming Supersaurus specimen described by Lovelace et al. (2008).
Here’s a tibia.
And a dorsal vertebra. I’m such a ninny, because the centrum is a little out-of-round I assumed that this was a cast of BYU 9044, the ‘Ultrasauros’ holotype vertebra. I didn’t figure out that it was a piece of Jimbo until I was on the road. *facepalm*
Anyway, in sauropod circles we refer to vertebrae like this as “real darn big”, the last size category before “stupidly huge”.
A dorsal rib, upside down. Pneumatic! Some cool art by Russell Hawley lurking behind.
And here’s the Jimbo mount at the Wyoming Dinosaur Center in Thermopolis.
Both the Tate and the WDC need a lot more nice things said about them by me, but this trip is still in progress, so all that will just have to wait.
Reference
I gave my keynote talk last evening at the 28th Annual Tate Conference. I also passed out the handout shown above so people could have a handy reference for sauropod biology while I was talking. I have a link to a PDF version at the bottom of this post if you’d prefer it that way.
Now that the talk’s done, I’m letting my “abstract” out into the world, here (link) and at the bottom of this post. I put “abstract” in scare quotes because it’s a short paper with references and figures. The freedom to go big with the abstract is what convinced me to take on what were for me new and ambitious subjects.
A few caveats. Just on this trip I’ve seen and heard some things that make me question the usefulness of postcranial fusions — of the neurocentral joints, sacrum, scapulocoracoid, and cervical ribs — for assessing sauropod ontogeny. I don’t think fusions are completely useless, just highly variable, even more so than I thought in previous years (see tables and discussions in Wedel and Taylor 2013a and Hone et al. 2016). But some things I’ve been calling “subadults” based on unfused joints may actually have been done growing. And on the flip side, I think some things with fused joints may have still been growing. We need more histology!

Apaldetti et al. (2021: fig. 1). Note the restricted morphospace of post-Toarcian sauropods. Compare to Benson et al. (2013: fig. 13).
Two papers I should have cited in the abstract are Benson et al. (2018) and Apaldetti et al. (2021), who showed with math what I argued in the abstract on qualitative grounds: after a period of experimentation with different shapes, sizes, and body forms in the Late Triassic and Early Jurassic, sauropodomorphs settle down into the sauropod body form by sometime in the Early Jurassic, and they never go back.
One thing I want to make clear: the fact that sauropods have a more conserved body plan that many other dinosaurian clades doesn’t make them bad dinosaurs, it makes them weird dinosaurs. Sauropods were phenomenally successful, precisely because they did everything right that big mammals do wrong — I started typing the list but just look at the handout up top. But that ecological and evolutionary success happened within pretty strict morphological boundaries; the shortest-necked sauropods were still long-necked compared to most other animals, the shortest-tailed were still long-tailed, and the smallest (as adults) were still pretty big. That sauropods didn’t transgress those boundaries, and as far as we can tell never went back to being prosauropod-like, in 135 million years of making bucket-loads of fast-growing, morphologically variable offspring, is interesting to me. And if it turns out that sauropods did transgress those boundaries, either because we find weird new sauropods, or dinosaur phylogeny gets some seismic shake-ups (you’ve read the new Lovegrove et al. paper, yeah?), that will be even more interesting.

Three sauropods from different times, places and clades, showing the conserved sauropod body plan. The basal eusauropod Spinophorosaurus from the Middle Jurassic of Niger, the turiasaur Mierasaurus from the Early Cretaceous of Utah, and a saltasaurine titanosaur Ibirania from the Late Cretaceous of Brazil (not to scale). Can you guess which is which? The 7th, 8th and 9th letters in the following sequence give the Left/Center/Right positions of Spinophorosaurus, Mierasaurus, and Ibirania, respectively: LCRCLRCRLRLC. Traced and lightly reposed from Remes et al. (2009), Royo-Torres et al. (2017), and Navarro et al. (2022). Wedel (2024: fig. 1).
My friend and colleague Jeremiah Scott helped me thrash through the literature on evolutionary ratchets, Mike Taylor and Brian Engh helped me refine my thinking on the science, its limits, and how to present it, and Jenny Adams helped me make the handout. Any errors are mine.
A big thanks to all of the other speakers at Tate 2024. I’d list them by name but it’s late, I’m tired, and the talks were uniformly excellent, so I’ll just go with this: every one of you gave me new facts to ponder and new ideas to think about. It was probably the most consistently interesting day of talks I’ve seen in my life.
I ended the talk with something that’s not in the abstract but should be: all of the ideas in the abstract are hypotheses, not conclusions. They’re crying out to be tested. In the last paragraph of the abstract I highlighted some recent work that I admire, that gives us examples to emulate in attacking the outstanding problems in sauropod paleobiology.
I’ve been doing this for about a quarter century, and in that time the landscape of dinosaur science has shifted dramatically. I don’t know where we’ll be in another quarter century, but it won’t be where we are now, and that’s really cool and really exciting. Let’s roll.
References
- Apaldetti, C., Pol, D., Ezcurra, M.D. and Martínez, R.N., 2021. Sauropodomorph evolution across the Triassic–Jurassic boundary: body size, locomotion, and their influence on morphological disparity. Scientific Reports 11(1): 22534.
- Benson, R.B., Hunt, G., Carrano, M.T. and Campione, N., 2018. Cope’s rule and the adaptive landscape of dinosaur body size evolution. Palaeontology 61(1): 13-48.
- Hone, D.W.E., Farke, A.A., and Wedel, M.J. 2016. Ontogeny and the fossil record: what, if anything, is an adult dinosaur? Biology Letters 2016 12 20150947; DOI: 10.1098/rsbl.2015.0947.
- Lovegrove, J., Upchurch, P. and Barrett, P.M., 2024. Untangling the tree or unravelling the consensus? Recent developments in the quest to resolve the broad-scale relationships within Dinosauria. Journal of Systematic Palaeontology 22(1): 2345333.
- Wedel, M.J. 2024. The sauropod heresies: evolutionary ratchets, the taphonomic event horizon, and all the evidence we cannot see. The Jurassic: Death, Diversity, and Dinosaurs, 28th Annual Tate Conference abstract book: 35-38. (PDF handout: Wedel 2024 Tate handout FINAL)
- Wedel, Mathew J., and Michael P. Taylor. 2013. Neural spine bifurcation in sauropod dinosaurs of the Morrison Formation: ontogenetic and phylogenetic implications. Palarch’s Journal of Vertebrate Palaeontology 10(1): 1-34.
In opposition to my speech supporting the motion “the open access movement has failed”, here’s what Jessica Polka said in opposition to the motion.
The open access movement has not failed. It is in the process of succeeding.
Indeed, over 50% of papers are now open access. And this proportion is set to increase, for three reasons:
- Top-down leadership
- (Overdue) attention to cost and equity
- New filters
First, top-down leadership.
Richard Poynder argues that the movement has failed because “ownership” of the movement has been handed to universities and funders. To quote him:
OA was conceived as something that researchers would opt into. The assumption was that once the benefits of open access were explained to them, researchers would voluntarily embrace it – primarily by self-archiving their research in institutional or preprint repositories. But while many researchers were willing to sign petitions in support of open access, few (outside disciplines like physics) proved willing to practice it voluntarily.
Fundamentally, I agree. Individual scholars are still too hamstrung by their incentives to act alone, without the strength of collective action. Free thinking and individualism are prized in academia, with investigators evaluated based on how unique and iconoclastic their individual contributions are. And, in this competitive environment, sticking your head above the sand to question the rules of the game – the rules by which everyone who is evaluating you has succeeded – is not a recipe for success.
This is why I am grateful that funders, governments, and coalitions are finally stepping in at scale to change the rules. I believe it is the only pragmatic solution to this wicked problem. I’ll share some examples.
When discussing coordinated support for open access, we have to begin where the movement began: Latin America, which has been leading the way in coordinated support. For a quarter of a century, the publicly funded bibliographic database SciELO, based in Brazil, has been providing free access to scholarly journals. There are now over 1.2 million articles from over 1,600 journals in collections representing 16 different countries in south and central america and Africa.
And in 2018, a coalition called AmeliCA, which stands for OPen Knowledge in Latin America and the Global South, launched to strengthen partnerships between academic institutions and publishing infrastructure. 400+ journals, nearly 3,000 books, and 100 institutional repositories have joined.
But even outside of Latin America, in the last few years, we have seen prominent funders establish public access policies.
Europe has been making serious inroads since the establishment of the open access provisions of Horizon 2020. And when cOAlition S formed in 2018, it represented an unprecedented commitment to coordinate among governments and philanthropic organizations in support of open access.
In 2021, UNESCO released a recommendation on open science, elevating the cause to an international stage, and providing a strong moral imperative for individual governments to take action.
And in 2022, the United States White House Office of Science and Technology Policy released the Nelson memo, which ensured zero-embargo public access to federally-funded literature. When this takes effect at the end of 2025, we are going to see even greater strides towards open access and open data.
Second, we are seeing some movement on cost and equity. That’s long overdue, but at least it’s happening.
The declaration of the 2002 Budapest Open Access Initiative suggested that open access publishing would lower costs, and promote equity by “shar[ing] the learning of the rich with the poor and the poor with the rich.”
In fact, the concept of an article processing charge wasn’t even mentioned in the principles. Instead, the authors wrote:
Because price is a barrier to access, these new journals will not charge subscription or access fees, and will turn to other methods for covering their expenses. There are many alternative sources of funds for this purpose, including the foundations and governments that fund research, the universities and laboratories that employ researchers, endowments set up by discipline or institution, friends of the cause of open access, profits from the sale of add-ons to the basic texts, funds freed up by the demise or cancellation of journals charging traditional subscription or access fees, or even contributions from the researchers themselves. There is no need to favor one of these solutions over the others for all disciplines or nations, and no need to stop looking for other, creative alternatives.
Unfortunately, the creative alternative (that is to say, the article processing charge) created by the publishing industry is coming at a high cost. APCs increased 50 percent from 2010 to 2019. And with individual APCs reaching in to the six figures, it’s no surprise that in 2022, OSTP estimated that American taxpayers are already paying $390 to $798 million annually to publish federally funded research.
That’s why it’s so damaging that many recent policies, like the Nelson memo and plan S, don’t go far enough to reduce economic exploitation. Instead, the Nelson memo directs federal agencies to, quote, “allow researchers to include reasonable publication costs […] as allowable expenses in all research budgets,” which implies support for article processing charges. This model creates major challenges for researchers WITHOUT federal or other funds, to say nothing of those in low and middle income countries, or in fields where resources are less plentiful.
But, there is a light at the end of the tunnel.
In May 2023, the European Union’s council of ministers called for a “no pay” model, in which costs for disseminating and evaluating research are paid directly by institutions and funders. This can be achieved in several ways, including with “diamond” open access journals. CoAlition S’s responsible publishing proposal is another acknowledgement of the need for fundamental change. And the new Bill & Melinda Gates Foundation policy, which prevents the payment of APCs from grant funds, is a strong signal that the system is being questioned.
And the third reason open access will succeed: new filters.
Richard Poynder questions the very benefits of having information publicly accessible, given current developments around mis- and disinformation. He argues for having a “membrane between scientific research and the chaotic mess of false and arbitrary information that swirls around the web.”
Yes, preprints, the financial incentives around open access, and other forms of open publishing do tip the balance away from gatekeeping and toward inclusion. This means that the rate of spurious knowledge available is going to increase.
However, it also lulls us out of a false sense of security in a system that NEVER was equipped to form a fool-proof defense against misinformation. For proof of that, you can look back to the Wakefield paper, or to the current papermill crisis.
Instead, we need a better immune system for misinformation. To me, this looks like moving away from a model in which 2-3 invited peers, who cannot possibly be experts in everything covered in a highly interdisciplinary paper with 30 co-authors, are rushed to give their evaluation at a time when they are not at liberty to discuss the paper with their colleagues. Then, all the information about whether a paper is rigorous or interesting (and to whom) gets compressed down into a single value – the title of the journal in which it is published.
Luckily, many journals are conducting transparent review, in which the reports are published. But, In order to create a system that is powerful enough to identify and correct problems in the literature, we need to disseminate research to large audiences BEFORE putting a stamp of approval on it. We need to disentangle the functions of traditional journals into a “publish, review, curate” model in which preprints and other means of sharing research are the first step, and the entire community can then discuss the work together.
And beyond that, we need to continue to experiment with new ways of organizing knowledge altogether – and this is what we are seeking to support at Astera.
For example, there are many exciting experiments in publishing: integrating code with narratives (like the Notebooks Now initiative from AGU), micropublications (which are single figure papers), publishing individual modules that can be linked together (for example, Octopus.ac), creating machine-readable nanopublications (which break knowledge down into triples: a subject, predicate, and object), discourse graphs (that create knowledge graphs out of evidence and ideas), and many others.
These threads are going to come together to create a future in which knowledge is shared and interpreted in completely new ways. The success of the open access movement is going to both lay the foundation for, and maximize the benefits of, this technological transformation.
Tate 2024 road update
June 7, 2024

With my boy Colin Boisvert at BYU. He successfully defended his MS thesis, now he’s bound for OSU-Tulsa for doctoral work. You’ll hear more about his exploits reeeeaaaal soon.

Fossil vending machine in the BYU Museum of Paleontology. All casts, except for the shark teeth and pieces of Campo del Cielo meteorite. They also have bigger casts for sale in the back.

My brothers Venmoed me money for my birthday. BYU takes Venmo for fossil casts. That’s how I got a wee apatosaur femur for a road trip buddy.

With my other boy Julian Diepenbrock at the University of Wyoming Geological Museum. He showed me some of the sauropod material he’s writing up for his dissertation. It’s gonna blow yer danged minds.

That last cervical rib on the left is pretty intact, and really unfused. Hello, not-skeletally-mature B. parvus! UW 15556, formerly CM 563. Why yes, there is a lot of reconstruction going on. W4TP (not mine).

Pulled off the road for a through-the-window shot of this lovely lady, one of about a fudillion pronghorns I saw between Laramie and Casper. Not my best work, but a nice memento for me. Sadly she didn’t want to race me. Maybe next time.
Normally I crop, rotate, and color balance every photo within an inch of its life, but right now I have a talk to polish, hence the as-shot quality here. See you in the future — the real near future if you’re attending the 2024 Tate summer conference, “The Jurassic: Death, Diversity, and Dinosaurs”.
The SSP debate on “the open access movement has failed” — part 1: speech for the motion
June 5, 2024
As I noted a week ago, to my enormous surprise I was invited to be one of the two participants in the plenary debate the closes the annual meeting of my long-term nemesis, the Society for Scholarly Publishing. I was to propose the motion “The open access movement has failed” in ten minutes or less, followed by Jessica Polka’s statement against the motion; then each of us would make three-minute responses to the other before the debate was opened to the floor. What follows is the opening statement that I gave.
The motion before us is that the Open Access Movement has failed. To demonstrate the truth of this proposition, I have to identify what the “open access movement” actually is. And one of the problems that Rick Poynder pointed out in his Scholarly Kitchen interview is that there has never really been a single organization that represents “The Open Access Movement” in the way that the Open Source Initiative represents its movement. So we’re going to look at four initiatives going back 30 years.
We’ll skip over the World Wide Web itself, which was originally announced by Tim Berners-Lee in 1991 with the words:
The project started with the philosophy that much academic information should be freely available to anyone.
The first Open Access Movement we’ll consider was Stevan Harnad’s “Subversive Proposal” of 1994, calling on scholarly authors to self-archive their manuscripts in open repositories. This proposal led to the publication of a book, the development of the EPrints repository software and the creation of the CogPrints repository for cognitive sciences. But can it be said to have succeeded? To quote from the proposal: “If every scholarly author in the world […] established a globally accessible archive for every piece of esoteric writing he did […], the long-heralded transition from paper publication to purely electronic publication would follow suit almost immediately.”
Measured against this vision of a sweeping global change, This open access movement surely failed.
Now we consider a second open access movement: in 1999, Harold Varmus, director of the National Institutes of Health, published a proposal called E-BIOMED. I quote:
We envision a system for electronic publication in which existing journals, newly created journals, and an essentially unrestricted collection of scientific reports can be accessed and searched with great ease and without cost by anyone connected to the Internet.
Now, Harnad’s Subversive Proposal had failed due to insufficient grass-roots momentum. But the same fate could surely not befall E-BIOMED, which was backed by the might of the USA’s biggest civilian research agency.
But there was opposition. In a welcoming editorial about E-BIOMED, The Lancet noted “Much of the biomedical publishing community is scrambling to defend itself against what it sees as an unprecedented act of aggression.”
Looking back sadly ten years later, Varmus wrote: “The most shrill opposition came, disappointingly, from the staffs of many respected scientific and medical societies […] The for-profit publishing houses were also unhappy, and sent their lead lobbyist, the former congresswoman Pat Schroeder, to Capitol Hill to talk to members of my appropriations subcommittees.” — in other words, to get the NIH defunded in retribution.
And the societies and publishers got their way. E-BIOMED was dead on arrival. Twenty-five years on, it’s so thoroughly forgotten that it’s hard to find on the Internet. It doesn’t have a Wikipedia entry, and isn’t even mentioned in the entry for Harold Varmus.
So the E-BIOMED open access movement failed utterly.
A third open access initiative arrived in 2002: a conference that united 16 open access advocates with different perspectives and gave rise to the Budapest Open Access Initiative. Its foundational document finished with this plea:
We invite governments, universities, libraries, journal editors, publishers, foundations, learned societies, professional associations, and individual scholars who share our vision to join us in the task of removing the barriers to open access.
Publisher opposition was significant. This very society [the Society for Scholarly Publishing], hired the consultant Eric Dezenhall to discuss public relations strategies for discrediting open access — for example, equating subscription-based publishing with peer review, and messaging such as “Public access equals government censorship”.
The Budapest Initiative would have needed a tidal wave of support to achieve escape velocity. In the face of this opposition and institutional inertia, it only raised ripples.
So the Budapest open access movement failed.
And there are more. I could talk about
- The Public Library of Science (launched in 2003), and its progressive stagnation; or
- The Cost of Knowledge petition (2012) that started brightly but ultimately achieved only free access to a handful of journals.
But our time is limited, so let’s jump ahead to our fourth open access movement.
Coalition S launched in 2018: a group of 11 national research funding organizations, quickly joined by the World Health Organization and hefty private funders like the Gates Foundation and the Howard Hughes Medical Institute. The tagline on their website summarizes the goal: “Making full and immediate Open Access a reality”. Surely if anyone could create a successful open access movement, it would be this powerful and wealthy group?
Coalition S started by launching what they called Plan S, which required open access for grant-funded articles. It used a wrinkle in this requirement as leverage to transition subscription journals to open access. I quote from the document Guidance on the Implementation of Plan S:
Authors publish Open Access with a CC BY license in a subscription journal that is covered by a transformative agreement which has a clear and time-specified commitment to a full Open Access transition.
[…]
In 2023, Coalition S will initiate a formal review process that examines […] the effect of transformative agreements.
Well.
In June 2023, Coalition S published its analysis of journals that had signed up to the Transformative Journals programme. It showed that only 1% of the journals in the program had flipped to full open access. More encouragingly, 30% of journals were meeting their open-access growth targets. But 68% had failed to meet the targets they had signed up to. A quarter of the enrolled journals had an open access rate of 10% or less.
The report says:
The fact that so many titles were unable to meet their [open access] growth targets suggests that for some publishers, the transition to full and immediate open access is unlikely to happen in a reasonable timeframe.
Later that year, Coalition S published a review titled Five years of Plan S: a journey towards full and immediate Open Access. Even the title feels like an admission of defeat: can you really have a journey towards something immediate? The report affirms what the analysis had suggested. I quote:
Based on progress reports and the very low Open Access transformation rate of Transformative Journals, Coalition S decided to end its financial support for Transformative Arrangements.
So Plan S’s goal of transforming subscription journals to open access failed.
In fact, all these open access movements have failed.
So where do we stand now? Going right back to the start, Harnad’s Subversive Proposal said:
Paper publishers will then either restructure themselves (with the cooperation of the scholarly community) […] or they will have to watch as peer community spawns a brand new generation of electronic-only publishers.
That’s still true, and represents the only real threat open access has ever presented to publishers.
I quoted earlier the report in which Coalition S “decided to end its financial support for Transformative Arrangements.” But the report goes on to say this:
Instead, [Coalition S] will direct its efforts to more innovative and community-driven Open Access publishing initiatives. [It] acknowledges the growing need for alternative, not-for profit publishing models, and is actively involved in European and global efforts for Diamond open access.
Plan S has failed; but Coalition S is pivoting. The world’s richest research funders are getting together to build their own open access platforms. That should be cause for publishers to carefully consider whether, in their quest for short-term gains, they have painted themselves into a corner.
We’ve looked at four open access movements and touched on several more. Every one of them has failed. And they have failed, mostly, because of opposition, obstruction and short-term opportunism on the part of publishers who have exchanged their original mission for shareholder value optimization.
But each wave has washed further up the beach.
There are three questions for this group:
- How many more open access movements will fail before one succeeds?
- When it does, will it succeed with the help of publishers, or despite them? And most crucially:
- Will it succeed with publishers or without them?
But until that day comes, we can confidently say that the open access movement has failed.














