How birds breathe, in 184 words
February 3, 2022

Windpipe and lungs in pink, air sacs in teal. Steps 1 and 3 happen at the same time — one breath of air is moving through the lungs and into the air sacs in back (1) at the same time as an earlier breath of air is moving out of the lungs and into the air sacs up front (3). Steps 2 and 4 happen at the same time as well — the air sacs in back are blowing air through the lungs (2) while the air sacs in front are blowing air out the windpipe (4). Each breath of air is inside the bird for two inhalations and exhalations.
Our lungs are made up of millions of tiny bags. Breath in, fill the bags with fresh air, breathe out, empty the bags of spent air. But bird lungs are very different. They’re made up of millions of tiny tubes, like bundles of drinking straws, and those tubes are connected to big, empty air sacs, like balloons that spread throughout the body. When birds breathe in, some of the air goes through the lungs, and some skips the lungs and goes into the air sacs. Then when the bird breathes out, the air in the air sacs gets pushed through the tubes in the lungs. So birds get oxygen-rich air blown through their lungs both when they inhale and when they exhale. The lungs and air sacs of birds also send mini air sacs into the skeleton, and these create air-filled spaces inside the bones, akin to our sinuses. These air spaces in the skeleton are the footprint of the respiratory system. A lot of extinct dinosaurs have the same pattern of air spaces in their skeletons, so we think they breathed like birds.
— Jessie Atterholt and Matt Wedel
Case study: the conception, slooow gestation, and birth of the incomplete-necks paper
January 28, 2022
Last time, we looked briefly at my new paper Almost all known sauropod necks are incomplete and distorted (Taylor 2022). As hinted at in that post, this paper had a difficult and protracted genesis. I thought it might be interesting to watch the story of a published paper through its various stages of prehistory and history. Strap in, this is a long one — but hopefully of interest, especially to people who are just coming into academia and wonder how this stuff works in practice.

It’s never easy to identify when a thing started, but I suppose the first seeds of this paper were sown back in 2004, when Matt was planning a visit to London (to meet me in person for the first time, as it happens) and we were planning out what things we might do during the museum time we had booked. The Rutland cetiosaur was on our itinerary, and I wrote to Matt:
I also wondered about trying to measure the radius of curvature of any well-preserved condyles and cotyles. Are there any established procedures for doing this? (And is the material up to it?)
The answer, of course, is “no”. But that wasn’t apparent until I saw the material. That got me started thinking about all the kinds of mechanical analyses we’d like to do with fossil necks, and about how good we would need the material to be for the results to mean anything.
Those ideas percolated for some years.
May 19, 2011: I wrote How long was the neck of Diplodocus?, in which I considered some of the ways that the neck of the Carnegie Diplodocus is not quite so well established as we tend to assume, and went on to make similar observations about the Humboldt brachiosaur Giraffatitan “S II”.
September 18, 2011: I gave a talk (co-authored with Matt) at the Lyme Regis SVPCA, entitled Sauropod necks: how much do we really know?, the first half of which had grown out of the observations in that initial blog-post. (The second half was about the problems caused by the lack of preserved intervertebral cartilage in fossilised vertebrae, and that half became our 2013 PLOS ONE paper.)
September 20, 2013: I wrote Measuring the elongation of vertebrae, in which I discussed a problem with Elongation Index (EI): that crushing of cotyles makes both their vertical height and horizontal width unreliable to use in ratio with vertebral length.
June 4, 2014: I wrote The Field Museum’s photo-archives tumblr, featuring: airbrushing dorsals. Among other photos, I noted one of presacral 6 (probably D7) of the Brachiosaurus altithorax holotype, showing that before it was “restored” into its present state, it was a mosaic of bone fragments.
October 6, 2015: I submitted to PeerJ a manuscript based on these observations and others. At the same time, I published a preprint of the submitted manuscript, and briefly blogged about it under the title My most depressing paper. I expected that the paper would quickly be published in essentially its submitted form.
In the following days, the preprint and blogpost both quickly attracted many comments pointing out complete or near-complete sauropod necks that I had missed in the manuscript’s catalogue of such necks.
October 27, 2015 (only three weeks later!): I got back three reviews which were the very definition of “tough but fair”. They were written by three researchers whose sauropod work I hugely respect and admire — Paul Barrett, Paul Upchurch and Jeff Wilson — and they graciously acknowledged the strengths of the submission as well as bringing numerous justified criticisms. It’s traditional in acknowledgements sections to say nice things about the reviewers, but really these were everything one could hope for.
(I disagreed with only two of the many critical points made: one by Paul Upchurch, which we will come to later; and Paul Barrett’s recommendation that the illustrations should use only specimens in credentialled museums. For fossils, of course, that’s right. But the paper also contains numerous photos of extant-animal vertebrae from my own collection, and that’s OK — common — even, in the extant-animal literature. A house-cat is a house-cat, and the cervicals of one are not going to be meaningfully different from those of another.)
Because it had taken the journals and the reviewers only three weeks to get detailed, helpful, constructive reviews back to me, I was now in a position to make this paper a big success story: to turn the revisions around quickly, and maybe even get an acceptance within a month of submission. The time was right: the material was still fresh in my mind so soon after the initial submission, so it should have been the work of a few evenings to revise according to the reviewers’ requests and get this thing on the road.
That’s not what happened.
Instead, for reasons I can’t begin to fathom, I became downhearted at the prospect of going back to this manuscript and dealing with all the criticisms. I want to emphasize again that this is not in any way a complaint about the reviews, which were not unduly negative. I just looked at them and felt … weary. So I let it slide for a while.
The problem is, “a while” quickly became multiple months. And by then, the material was no longer fresh in my mind, so that doing the work I should have done half a year earlier would now have been a much bigger job. I would have had to load lots of stuff back into mental RAM before I could even get started. And there was always something more appealing to do. So I left it for a full year.
The problem is, “a year” quickly became multiple years. I have no excuse for this.

And for six years, this unconsummated project has been hanging over me, draining my motivation, whispering to me every time I try to work on something else. It’s been a drag on everything I’ve tried to do in palaeo, all because I didn’t summon the energy to drive a stake through its heart back in 2015.
Learn from my mistake, folks: don’t do this.
When you get the reviews back from a submission, give yourself a week to mourn that the reviewers didn’t recognise the pristine perfection of your initial submission, then get back on the horse and do the work. Just like I didn’t.
Seriously: be better than me. (That’s certainly what I plan to do.)
Anyway …
Early 2021: I finally got my act together, and got started on the big revision. And by this point it was a big revision because not only did I have to handle all those long-postponed reviews, and all the comments on the preprint and the blog-posts from 2015. I also had to handle five more years of developments. The biggest effect this had was that I needed to completely rewrite the woefully inadequate catalogue of complete necks, which in the original preprint listed only six species. The new version lists specimens rather than species, and very many more of them. To make the list as comprehensive as possible this time …
January 27, 2021: I created my initial draft of the new list as a Google Doc, and posted Towards a catalogue of complete sauropods necks asking readers on this blog to offer corrections and additions. They did. That resulted in a lot more work as I chased down details of candidate necks in published sources and sought personal communications about others. As a result …
March 24, 2021: I posted the draft list as The catalogue of complete sauropods necks nears completion. A few more comments came in as a result, but the list was apparently approaching a steady state.
March 27, 2021: Matt dropped me a line breaking down the listed necks across a basic phylogeny of sauropods, and counting the occurrences. I thought this was interesting enough to make up a new illustration, which I posted on the blog as Analysing the distribution of complete sauropod necks and added to the in progress revised manuscript.
May 11, 2021: I was working on finding a way to measure the variation of cotyle aspect ratios along preserved necks, so I could show qualitatively that they vary more in sauropod fossils than in bones of extant amniotes. I came up with a way of calculating this, but wondered if it already existed. In my post Help me, stats people! I asked if anyone knew of it, but it seemed no-one did. (In the end, the resubmitted paper offered two versions of this metric: one additive, the other multiplicative. To the best of my knowledge, these are novel, if simple, contributions.)
June 6, 2021: In one of the original reviews, Paul Upchurch had commented that a further confounding factor in understanding neck lengths is identifying the cervicodorsal junction. I started to put together a new manuscript section on that issue, and posted my initial thoughts as What’s the difference between a cervical and dorsal vertebra?. This post, too, generated some useful feedback that made its way into the version of the section that landed up in the revised paper.
At this point, I had put together much of the new material I needed for the resubmission. So I went back to the revised draft, integrated all the new and modified material, and …
July 12 2021: I submitted the new manuscript. Because it was the best part of six years since the old version had been touched, I asked PeerJ to handle it as a new submission, and invited the handling editor to solicit reviews either from the same people who’d done the first round or from different people, as they saw fit. This time I did not also post a pre-print — I really didn’t need yet more comments coming in at this point, I just needed to get the wretched thing over the line.
September 3 2021: the editorial decision was in, based on three reviews: major revisions. sigh. Again, though, the reviewers’ criticisms were mostly legitimate, and I could sympathise with the editor’s decision. One of the reviewers of the new version — Paul Upchurch — had previously reviewed the 2015 version, but the other two were new.
Needless to say, more work was required in response to these new reviews, but it was much more tractable than the big revision had been. I added a brief discussion of retrodeformation. I wrote about how we can use phylogenetic bracketing to estimate cervical counts, and three reasons why this doesn’t work as well as we’d like. I discussed how explicit documentation of articulation and damage mitigates their misleading effects. I removed a sideswipe at the journal Science, which I have to admit was out of place. I added a discussion of different definitions of the elongation index. I clarified the prose to make it clearer that my goal was not to criticise how others had done things, but to lay out for new researchers what pitfalls they will have to deal with.
But the most fundamental issue that arose in this round of review was whether the paper should be published at all. I will quote from Paul Upchurch’s review (since it is freely available, along with all the other reviews and my responses):
I have [a] fundamental, and I fear fatal, [problem] with this paper. First, and most importantly, I think it attempts to address a problem that does not really exist. It sets up a strawman with regard to the need to tell researchers that sauropod necks are less complete than we previously thought. However, I would argue that we are well aware of these issues and that the current paper does not provide convincing evidence that there is a problem with the way we are doing things now. To be clear, I am not saying that the incompleteness of sauropod necks is not a problem – it definitely is. What I’m saying is that there is little value in a paper whose main message is to tell us what we already know and take into account.
(Let me emphasize again that this criticism came in the context of a review that was careful, detailed and in many ways positive. There was absolutely nothing malicious about it — it was just Paul’s honest opinion.)
The interesting thing about this criticism is that there was absolutely nothing I could do to remedy it. A paper criticised for lacking a phylogenetic analysis can be made acceptable to the reviewers by adding a phylogenetic analysis. But a paper criticised for not needing to exist can only stand or fall by the handling editor’s agreement with either the author or the reviewer. So all I could do was write a response in the letter than accompanied my revision:
We now come to Paul’s fundamental issue with this paper: he does not believe it is necessary. He writes “The scientific community working on these issues does not need to be reminded of the general importance of understanding the limitations on the data we use”. Here I suggest he is misled by his own unique perspective as the person who quite possibly knows more about sauropods than anyone else alive. Labouring under “The curse of knowledge”, he charitably assumes other palaeontologists are as well-read and experienced as he is — but almost no-one is. I know that I, for one, desperately needed a paper along these lines when I was new to the field.
Happily, the handling editor agreed with me — as did the other two reviewers, which surely helped: “in a time of ever more sophisticated methods, it is good to be made aware of the general imperfections of the fossil record […] I thus recommend the article for publication”. So:
November 11 2021: I submitted the revised revision, along with the response letter quoted in part above.
December 15 2021: The editor requested some more minor changes. I made some of them and pushed back on a few others, then:
December 20 2021: I submitted a third version of this second attempt at the paper.
December 28 2021 (a welcome belated Christmas present): the paper was finally accepted. From here on, it was just a matter of turning handles.
January 4 2022: The proof PDF arrived, looking lovely but riven with mistakes — some of them my own, having survived multiple rounds of revision; others introduced by the typesetting process, including some unwelcome “corrections” that created new errors.
January 13 2022: I sent back a list of 56 errors that needed correcting.
January 24 2022: The paper was published at PeerJ!
Being of a pedantic turn of mind, I went through the final typeset version to check that all the proofing errors had been fixed. Most had, of course. But one in being fixed had introduced another; another was partially corrected but is still missing an apostrophe in the final version. Small stuff.
And then I went through the “things to do when a paper comes out” checklist: posting an SV-POW! article that I had prepared in the days leading up to publication; updating the SV-POW! sidebar page for this paper; adding the new paper to my publications list (and removing the separate entry for the 2015 preprint); adding it to my univeristy’s IR; adding it to my ORCiD page (though if you omit this, it seems to figure it out on its own after a while — kudos!); and skipping LinkedIn, Mendeley, ResearchGate, Academia.edu and Facebook, none of which I do.
And with that, the quest really is at an end, barring this post and any others that might occur to me to write (I have nothing more planned at this point).
Now it’s time to get that vertebral orientation paper revised and resubmitted!
References
Pneumatization sites: how does air get into vertebrae?
December 8, 2021
Science doesn’t always get done in the right order.
In the course of the research for my paper with Mike this past spring, “Why is vertebral pneumaticity in sauropod dinosaur so variable?”, published in Qeios in January, I had a couple of epiphanies. The first was that I had collated enough information to map the sites at which arteries and veins enter and exit the vertebrae in most tetrapods. The second was that, having done that, I’d also made a map of (almost) all the places that diverticula enter the vertebrae to pneumatize them. This is obviously related to the thesis we laid out in that paper, that postcranial skeletal pneumaticity is so variable because pneumatic diverticula follow pre-existing blood vessels as they develop, and blood vessels themselves are notoriously variable. In fact, if you had to summarize that thesis in one diagram, it would probably look like the one above, which I drew by hand in my research notebook in early March.
Only that’s not quite correct. I didn’t have those epiphanies “in the course of the research”, I had them after the pneumatic variation paper was done and published. And at the time they felt less like epiphanies and more like a series of “Holy crap” realizations:
- Holy crap, that diagram would have been really helpful when we were writing the pneumatic variation paper, since it establishes, almost tautologically, that diverticula invade vertebrae where blood vessels already have. In a rational world, Mike and I would have done this project first, and the pneumatic variation paper would have stood on its shoulders.
- Holy crap, how have I been working on vertebral pneumaticity for more than two decades without ever creating a map of all the places a vertebra can be pneumatized, or even realizing that such a map would be useful?
- Holy crap, how have I been working on dinosaur bones — and specifically their associated soft tissues — for more than two decades without wondering exactly how the blood was getting into and out of each bone?
Arguably, not only should Mike and I have done this project first, I should have taken a stab at it way back when I was working on my Master’s thesis. Better late than never, I guess.
I used a sauropod caudal as my vertebral archetype because it has all the bits a tetrapod vertebra can have, including the hemal arch or chevron. This was important, because Zurriaguz et al. (2017) demonstrated that the chevrons are pneumatic in some titanosaurs.
For the actual presentation I redrew the vessels on top of a scan of a Camarasaurus caudal from Marsh, which Mike found and cleaned up (modified from Marsh 1896: plate 34, part 4, and plate 39, part 3c).
We deliberately used an unfused caudal to emphasize that ‘ribs’ — technically, costal elements — are present, they just fuse to the neural arch and centrum rather than remaining separate, mobile elements like dorsal ribs.
Anyway, I’m yapping about this now because this project is rolling: Mike and I submitted an abstract on it for the 3rd Palaeontological Virtual Congress, and a short slideshow on the project is now up at the 3PVC site for attendees to look at and comment on. The congress started last Wednesday and runs through Dec. 15, after which I’m sure we’ll submit the abstract and slide deck somewhere as a preprint, and then turn it into a paper as quickly as possible.
I’ll probably have more to say on this in a day or so, but for now the comment field is open, and your thoughts are welcome.
References
- Marsh, O.C. 1896. The Dinosaurs of North America. 16th annual report of the U. S. Geological Survey, 1894-95, pt. I. US Government Printing Office, Washington, D.C.
- Taylor, Michael P., and Mathew J. Wedel. 2021. Why is vertebral pneumaticity in sauropod dinosaurs so variable? Qeios 1G6J3Q. doi:10.32388/1G6J3Q
- Zurriaguz, V., Martinelli, A., Rougier, G.W. and Ezcurra, M.D. 2017. A saltasaurine titanosaur (Sauropoda: Titanosauriformes) from the Angostura Colorada Formation (upper Campanian, Cretaceous) of northwestern Patagonia, Argentina. Cretaceous Research 75: 101-114.
Long before Matt and others were CT-scanning sauropod vertebrae to understand their internal structure, Werner Janensch was doing it the old-fashioned way. I’ve been going through old photos that I took at the Museum für Naturkunde Berlin back in 2005, and I stumbled across this dorsal centrum:
You can see a transverse crack running across it, and sure enough the front and back are actually broken apart. Here there are:

The same dorsal vertebral centrum of ?Giraffatitan, bisected transversely in two halves. Left: anterior half in posterior view; right: posterior half in anterior view. I had to balance the anterior half on my shoe to keep it oriented corrrectly for the photo.
This does a beautiful job of showing the large lateral foramina penetrating into the body of the centrum and ramifying further into the bone, leaving only a thin midline septum.
But students of the classics will recognise this bone immediately as the one that Janensch (1947:abb. 2) illustrated the posterior half of in his big pneumaticity paper:
It’s a very strange feeling, when browsing in a collection, to come across a vertebra that you know from the literature. As I’ve remarked to Matt, it’s a bit like running into, say, Cameron Diaz in the corner shop.
Reference
- Janensch, W. 1947. Pneumatizitat bei Wirbeln von Sauropoden
und anderen Saurischien. Palaeontographica, supplement
7:1-25.
Werner Janensch, Wannabe, Lovefool
November 22, 2019
Here’s how I got my start in research. Through a mentorship program, I started volunteering at the Oklahoma Museum of Natural History in the spring of 1992, when I was a junior in high school. I’d been dinosaur-obsessed from the age of three, but I’d never had an anatomy course and didn’t really know what I was doing. Which is natural! I had no way of knowing what I was doing because I lacked training. Fortunately for me, Rich Cifelli took me under his wing and showed me the ropes. I started going out on digs, learned the basics of curatorial work, how to mold and cast fossils, how to screenwash matrix and then pick microfossils out of the concentrate under a dissecting microscope, and—perhaps most importantly—how to make a rough ID of an unidentified bone by going through the comparative element collection until I found the closest match.
All set, right? Ignition, liftoff, straight path from there to here, my destiny unrolling before me like a red carpet.
No.
It could have gone that way, but it didn’t. I had no discipline. I was a high-achieving high school student, but it was all to satisfy my parents. When I got to college, I didn’t have them around to push me anymore, and I’d never learned to push myself. I went off the rails pretty quickly. Never quite managed to lose my scholarships, without which I could not have afforded to be in college, period, but I skimmed just above the threshold of disaster and racked up a slate of mediocre grades in courses from calculus to chemistry. I even managed to earn a C in comparative anatomy, a fact which I am now so good at blocking out that I can go years at a time without consciously recalling it.
After three years of this, I had the most important conversation of my life. Because I was a zoology major I’d been assigned a random Zoology Dept. faculty member as an undergrad advisor. I was given to Trish Schwagmeyer, not because we got on well (we did, but that was beside the point) or had similar scientific interests, just luck of the draw. And it was lucky for me, because in the spring of 1996 Trish looked at my grades from the previous semester, looked me in the eye, and said, “You’re blowing it.” She then spent the next five minutes explaining in honest and excruciating detail just how badly I was wrecking my future prospects. I’ve told this story before, in this post, but it bears repeating, because that short, direct, brutal-but-effective intervention became the fulcrum for my entire intellectual life and future career.
Roughly an hour later I had the second most important conversation of my life, with Rich Cifelli. While I’d been lost in the wilderness my museum volunteering had petered out to zero, and Rich would have been completely justified in telling me to get lost. Not only did he not do that, he welcomed me back into the fold, in a terrifyingly precise recapitulation of the Biblical parable of the prodigal son. When I asked Rich if I could do an independent study with him in the next semester, he thought for a minute and said, “Well, we have these big dinosaur vertebrae from the Antlers Formation that need to be identified.” Which is how, at the age of 21, with a rubble pile of an academic transcript and no real accomplishments to stand on, I got assigned to work on OMNH 53062, the future holotype of Sauroposeidon proteles.
I was fortunate in four important ways beyond the forgiveness, patience, and generosity of Richard Lawrence Cifelli:
- OMNH 53062 was woefully incomplete, just three and a half middle cervical vertebrae, which meant that the project was small enough in concept to be tractable as an independent study for an undergrad. Rich and I both figured that I’d work on the vertebrae for one semester, come up with a family-level identification, and maybe we’d write a two-pager for Oklahoma Geology Notes documenting the first occurrence of Brachiosauridae (or whatever it might turn out to be) in the vertebrate fauna of the Antlers Formation.
- Because the specimen was so incomplete, no-one suspected that it might be a new taxon, otherwise there’s no way such an important project would have been assigned to an undergrad with a spotty-to-nonexistent track record.
- Despite the incompleteness, because the specimen consisted of sauropod vertebrae, it held enough characters to be identifiable–and eventually, diagnosable. Neither of those facts were known to me at the time.
- All of Rich’s graduate students were already busy with their own projects, and nobody else was about to blow months of time and effort on what looked like an unpromising specimen.
There is a risk here, in that I come off looking like some kind of kid genius for grasping the importance of OMNH 53062, and Rich’s other students look like fools for not seeing it themselves. It ain’t like that. The whole point is that nobody grasped the importance of the specimen back then. It would take Rich and me a whole semester of concentrated study just to come to the realization that OMNH 53062 might be distinct enough to be diagnosable as a new taxon, and a further three years of descriptive and comparative work to turn that ‘maybe’ into a paper. People with established research programs can’t afford to shut down everything else and invest six months of study into every incomplete, garbage-looking specimen that comes down the pike, on the off chance that it might be something new. Having the good judgment to not pour your time down a rat-hole is a prerequisite for being a productive researcher. But coming up with a tentative ID of an incomplete, garbage-looking specimen is a pretty good goal for a student project: the student learns some basic comparative anatomy and research skills, the specimen gets identified, no existing projects get derailed, and no-one established wastes their time on what is most likely nothing special. If the specimen does turn out to be important, that’s gravy.
So there’s me at the start of the fall of 1996: with a specimen to identify and juuuust enough museum experience, from my high school mentorship, to not be completely useless. I knew that one identified a fossil by comparing it to known things and looking for characters in common, but I didn’t know anything about sauropods or their vertebrae. Rich got me started with a few things from his academic library, I found a lot more in OU’s geology library, and what I couldn’t find on campus I could usually get through interlibrary loan. I spent a lot of time that fall standing at a photocopier, making copies of the classic sauropod monographs by Osborn, Hatcher, Gilmore, Janensch, and others, assembling the raw material to teach myself sauropod anatomy.
In addition to studying sauropods, I also started going to class, religiously, and my grades rose accordingly. At first I was only keeping up with my courses so that I would be allowed to continue doing research; research was the carrot that compelled me to become a better student. There was nothing immediate or miraculous about my recovery, and Rich would have to give me a few well-deserved figurative ass-kickings over the next few years when I’d occasionally wander off course again. But the point was that I had a course. After a few months I learned—or remembered—to take pride in my coursework. I realized that I had never stopped defining myself in part by my performance, and that when I’d been adrift academically I’d also been depressed. It felt like crawling out of a hole.
(Aside: I realize that for many people, depression is the cause of academic difficulty, not the reverse, and that no amount of “just working harder” can offset the genuine biochemical imbalances that underlie clinical depression. I sympathize, and I wish we lived in a world where everyone could get the evaluation and care that they need without fear, stigma, crushing financial penalties, or all of the above. I’m also not describing any case here other than my own.)
Out of one hole, into another. The biggest problem I faced back then is that if you are unfamiliar with sauropod vertebrae they can be forbiddingly complex. The papers I was struggling through referred to a pandemonium of laminae, an ascending catalog of horrors that ran from horizontal laminae and prespinal laminae through infraprezygapophyseal laminae and spinopostzygapophyseal laminae. Often these features were not labeled in the plates and figures, the authors had just assumed that any idiot would know what a postcentrodiapophyseal lamina was because, duh, it’s right there in the name. But that was the whole problem: I didn’t know how to decode the names. I had no map. SV-POW! tutorials didn’t exist. Jeff Wilson’s excellent and still-eminently-useful 1999 paper codifying the terminology for sauropod vertebral laminae was still years in the future.
Then I found this, on page 35 of Werner Janensch’s 1950 monograph on the vertebrae of what was then called Brachiosaurus brancai (now Giraffatitan):
It was in German, but it was a map! I redrew it by hand in my very first research notebook, and as I was copying down the names of the features the lightbulb switched on over my head. “Diapophyse” meant “diapophysis”, and it was the more dorsal of the two rib attachments. “Präzygapophyse” was “prezygapophysis”, and it was one of the paired articular bits sticking out the front of the neural arch. And, crucially, “Präzygodiapophysealleiste” had to be the prezygodiapophyseal lamina, which connected the two. And so on, for all of the weird bits that make up a sauropod vertebra.
It’s been 22 years and I still remember that moment of discovery, my pencil flying across the page as I made my own English translations of the German anatomical terms, my mind buzzing with the realization that I was now on the other side. Initiated. Empowered. I felt like I had pulled the sword from the stone, found Archimedes’ lever that could move the world. In the following weeks I’d go back through all of my photocopied sauropod monographs with my notebook open to the side, reading the descriptions of the vertebrae for the second or third times but understanding them for the first time, drawing the vertebrae over and over again until I could call up their basic outlines from memory. This process spilled over from the fall of 1996 into the spring of 1997, as Rich and I realized that OMNH 53062 would require more than one semester of investigation.
My memories of those early days of my sauropod research are strongly shaped by the places and circumstances in which I was doing the work. Vicki and I had gotten married in the summer of 1996 and moved into a two-bedroom duplex apartment on the north side of Norman. The upstairs had a long, narrow bathroom with two sinks which opened at either end onto the two upstairs bedrooms, the one in which we slept and the one we used as a home office. In the mornings I could get showered and dressed in no time, and while Vicki was getting ready for work or school I’d go into the office to read sauropod papers and take notes. Vicki has always preferred to have music on while she completes her morning rituals, so I listened to a lot of Top 40 hits floating in from the other upstairs rooms while I puzzled out the fine details of sauropod vertebral anatomy.
Two songs in particular could always be counted on to play in any given hour of pop radio in the early spring of 1997: Wannabe by the Spice Girls, and Lovefool by the Cardigans. I am surely the only human in history to have this particular Pavlovian reaction, but to this day when I hear either song I am transported back to that little bedroom office where I spent many a morning poring over sauropod monographs, with my working space illuminated by the light of the morning sun pouring through the window, and my mind illuminated by Werner Janensch, who had the foresight and good grace to give his readers a map.
If you want to know what I thought about OMNH 53062 back in 1997, you can read my undergraduate thesis—it’s a free download here. Looking back now, the most surprising thing to me about that thesis is how few mentions there are of pneumaticity. I met Brooks Britt in the summer of 1997 and had another epochal conversation, in which he suggested that I CT scan OMNH 53062 to look at the air spaces inside the vertebrae. I filed my undergrad thesis in December of 1997, and the first session CT scanning OMNH 53062 took place in January, 1998. So in late 1997 I was still a pneumaticity n00b, with no idea of the voyage I was about to embark upon.
In 2010, after I was settled in as an anatomist at Western University of Health Sciences, I wrote a long thank-you to Trish Schwagmeyer. It had been 14 years since that pivotal conversation, but when she wrote back to wish me well, she still remembered that I’d gotten a C in comparative anatomy. I’d have a chance to make amends for that glaringly anomalous grade later the same year. At ICVM in Punta del Este, Uruguay, I caught up with Edie Marsh-Matthews, who had taught my comparative anatomy course back when. I apologized for having squandered the opportunity to learn from her, and she graciously (and to my relief) shifted the conversation to actual comparative anatomy, the common thread that connected us in the past and the present.
If the story has a moral, it’s that I owe my career in large part to people who went out of their way to help me when I was floundering. And, perhaps, that the gentle approach is not always the best one. I needed to have my head thumped a few times, verbally, to get my ass in gear, when less confrontational tactics had failed. I slid easily through the classrooms of dozens of professors who watched me get subpar grades and didn’t try to stop me (counterpoint: professors are too overworked to invest in every academic disaster that comes through the door, just like paleontologists can’t study every garbage specimen). If Trish Schwagmeyer and Rich Cifelli had not decided that I was worth salvaging, and if they not had the grit to call me out on my BS, I wouldn’t be here. As an educator myself now, that thought haunts me. I hope that I will be perceptive enough to know when a student is struggling not because of a lack of ability but through a lack of application, wise enough to know when to deploy the “you’re blowing it” speech, and strong enough to follow through.
References
- Gilmore Charles W. 1936. Osteology of Apatosaurus, with special reference to specimens in the Carnegie Museum. Memoirs of the Carnegie Museum 11:175–300 and plates XXI–XXXIV.
- Janensch, Werner. 1950. Die Wirbelsaule von Brachiosaurus brancai. Palaeontographica (Suppl. 7) 3: 27-93.
- Wedel, M.J. 1997. A new sauropod from the Early Cretaceous of Oklahoma. Undergraduate honor thesis, Department of Zoology, University of Oklahoma, Norman, OK. 43pp.
- Wilson, J.A. 1999. A nomenclature for vertebral laminae in sauropods and other saurischian dinosaurs. Journal of Vertebrate Paleontology 19: 639-653.
Final bonus image so when I post this to Facebook, it won’t grab the next image in line and crop it horribly to make a preview. This is me with OMNH 1670, in 2003 or 2004, photo by Andrew Lee.
Things to Make and Do, Part 25: cleaning bird vertebrae
December 24, 2018
When I started working on sauropods, I thought their vertebrae were cool but they were loaded with weird structures that I didn’t understand. Then I dissected my first ostrich neck and suddenly everything made sense: this was a muscle attachment, that was a pneumatic feature, this other thing was a ligament scar. Everyone who is interested enough to read this blog should give themselves the same “Aha!” moment. You don’t even have to eat the birds yourselves, lots of people don’t like bird necks and will give them away if you ask.
If you get a whole bird, the neck is usually included with the giblets. Around Thanksgiving and Christmas you can often find bundles of spare turkey necks at your grocer or butcher.
This spring I picked up some smoked turkey necks at the grocery store. I wanted to make turkey stew and I figured I might as well get some toys in the bargain. Here are some neck segments in the crock pot.
And here they are after a few hours of cooking. Time to separate the meat from the bones. That neck segment in the middle of the above photo is a pretty good match for the ostrich neck cross-section in this post.
Here are parts of three vertebrae with the long, multi-segment muscles removed, but with the shorter single-segment muscles still connecting them. Anterior is to the right; that’s a cervical ribs sticking out at the lower right “corner”.
Here’s a single intact cervical in left lateral view with most of the meat off, but ready for a long simmer to loosen the remaining crud. This is roughly the same orientation as the lateral view of Mike’s famous turkey cervical.
Meat goes back in the pot.
Bones go on to the next stage: simmering. One of the nice things about the stepwise process of cleaning bones is that you can stop at any point, put the bones in the freezer, and come back days or months later. This bowl of bones went into the freezer in exactly the state you see here, and I didn’t pull them out and finish cleaning them until last week.
If you have a pot-sized strainer, it makes things easier, especially for rinsing. These aren’t turkey vertebrae, these are the verts from my Thanksgiving ducks. But the principle and the process are the same.
After simmering for an hour or two, it’s time to pick off the loosened muscles, ligaments, cartilage, and so on. Here are two similar turkey cervicals after simmering, in dorsal view with anterior to the right. The one on the left has not been cleaned and has all kinds of crud stuck to it, including a big chunk of intervertebral ligament sticking out between the rami of the postzygapophyses. The one on the right has been through a first-pass cleaning.
What tools should you use? Whatever you have to hand. I like old toothbrushes for scrubbing off little bits of muscle and tendon, toothpicks for shoving spinal cord bits through the neural canal and for picking bits of meat out of hard-to-reach places, and the Mark 1 thumbnail for planing off articular cartilage, as shown here with the back end of a duck cervical.
Here’s the outcome of a cleaning session: on the left, the bowl I used for cleaning the vertebrae. In the top middle, the pile of gloop I pulled off. And on the right, a bowl of cleaned turkey and duck vertebrae, ready for degreasing.
Here are the vertebrae of a couple of ducks after soaking overnight in 3% hydrogen peroxide, the ordinary stuff you get at the drugstore or dollar store.
Here’s another bowl with turkey vertebrae. They were all at the bottom of the bowl when I went to bed, floating when I got up the next morning. This is pretty common with lightweight pneumatic vertebrae: the oxygen bubbling out of the hydrogen peroxide has gotten trapped in the internal air spaces and made the vertebrae buoyant.
After a night in the hydrogen peroxide, it’s time to rinse and dry the vertebrae. I put this mixed lot of turkey and duck verts on a plate with a paper towel and left them out on the kitchen counter. In the summertime, when it’s hot and dry, I might put them outside for a bit and they’d be dry in a couple of hours. Indoors in the winter it can take a couple of days for the vertebrae to get completely dry.
Here’s the same batch of vertebrae a couple of days later, clean and dry and ready for whatever comes next.
Which bird should you use? Bigger birds have vertebrae that are easier to clean, harder to damage, and more fun to look at, but use whatever you can get your hands on. This photo shows the axis, a middle cervical, and a posterior cervical from the turkey (top) and duck (bottom). Note that the duck was so young that the cervical ribs hadn’t fused and they fell off during the cleaning process.
If you’ve been following along, you have some nice clean bird vertebrae to play with. So what now — what should you do with them? That will the subject of an upcoming post (UPDATE: this one). Stay tuned!