DIY dinosaurs: more dinosaur bone standees
January 25, 2023
Michelle Stocker with an apatosaur vertebra (left) and a titanosaur femur (right), both made from foam core board.
In the last post I showed the Brachiosaurus humerus standee I made last weekend, and I said that the idea had been “a gleam in my eye for a long time”. That’s true, but it got kicked into high gear late in 2021 when I got an email from a colleague, Dr. Michelle Stocker at Virginia Tech. She wanted to know if I had any images of big sauropod bones that she could print at life size and mount to foam core board, to demonstrate the size of big sauropods to the students in her Age of Dinosaurs course. We had a nice conversation, swapped some image files, and then I got busy with teaching and kinda lost the plot. I got back to Michelle a couple of days ago to tell her about my Brach standee, and she sent the above photo, which I’m posting here with her permission.
That’s OMNH 1670, a dorsal vertebra of the giant Oklahoma apatosaurine and a frequent guest here at SV-POW!, and MPEF-PV 3400/27, the right femur of the giant titanosaur Patogotitan, from Otero et al. (2020: fig. 8). (Incidentally, that femur is 236cm [7 feet, 9 inches] long, or 35cm longer than our brachiosaur humerus.) For this project Michelle vectorized the images so they wouldn’t look low-res, and she used 0.5-inch foam core board. She’s been using both standees in her Age of Dinosaurs class at VT (GEOS 1054) every fall semester, and she says they’re a lot of fun at outreach events. You can keep up with Michelle and the rest of the VT Paleobiology & Geobiology lab group at their research page, and follow them @VTechmeetsPaleo on Twitter.
Michelle’s standees are fully rad, and naturally I’m both jealous and desirous of making my own. I’ve been wanting a plywood version of OMNH 1670 forever. If I attempt a Patagotitan femur, I’ll probably follow Michelle’s lead and use foam core board instead of plywood — the plywood Brach humerus already gets heavy on a long trek from the house or the vehicle.
Speaking of, one thing to think about if you decide to go for a truly prodigious bone is how you’ll transport it. I can haul the Brach humerus standee in my Kia Sorento, but I have to fold down the middle seats and either angle it across the back standing on edge, or scoot the passenger seat all the way forward so I can lay it down flat. I could *maybe* get the Patagotitan femur in, but it would have to go across the tops of the passenger seats and it would probably rest against the windshield.
Thierra Nalley and me with tail vertebrae of Haplocanthosaurus (smol) and the giant Oklahoma apatosaur (ginormous), at the Tiny Titan exhibit opening.
As long as I’m talking about cool stuff other people have built, a formative forerunner of my project was the poster Alton Dooley made for the Western Science Center’s Tiny Titan exhibit, which features a Brontosaurus vertebra from Ostrom & McIntosh (1966) blown up to size of OMNH 1331, the largest centrum of the giant Oklahoma apatosaurine (or any known apatosaurine). I wouldn’t mind having one of those incarnated in plywood, either.
I’ll bet more things like this exist in the world. If you know of one — or better yet, if you’ve built one — I’d love to hear about it.
References
- Alejandro Otero , José L. Carballido & Agustín Pérez Moreno. 2020. The appendicular osteology of Patagotitan mayorum (Dinosauria, Sauropoda). Journal of Vertebrate Paleontology, DOI: 10.1080/02724634.2020.1793158
- Ostrom, John H., and John S. McIntosh. 1966. Marsh’s Dinosaurs. Yale University Press, New Haven and London. 388 pages including 65 absurdly beautiful plates.
DIY dinosaurs: building a life-size Brachiosaurus humerus standee
January 23, 2023
Building life-size standees of big dinosaur bones has been a gleam in my eye for a long time. What finally pushed me over the edge was an invitation from Oakmont Outdoor School here in Claremont, California, to come talk about dinosaurs. It was an outdoor assembly, with something like 280 kids in attendance, and most of my show and tell materials are hand-sized and would not show up well from a distance. Plus, I wanted to blow people away with the actual size of big dinosaur bones.
I started with a life-size poster print of FHPR 17108, the complete right humerus of Brachiosaurus from Brachiosaur Gulch in Utah (the story of the discovery and excavation of that specimen is here). I used the image shown above, scaled to print at 7 feet by 3 feet. You can see that print lying on my living room floor in the previous post.
It was simpler and cheaper to get two 2 foot x 4 foot pieces of plywood than one big piece, so that’s what I did. I laid them out on the living room floor, cut out the poster print of the humerus from its background, traced the outline of the humerus onto the plywood, and then took the pieces outside to cut out the humerus shapes with a jigsaw.
The big piece of darker plywood is the brace that holds the two front pieces together. The smaller piece down at the distal end is a sort of foot, level with the bottom of the humerus but wider and flatter to give more stability. I used wood glue and a bunch of screws to hold everything together. Probably more screws than were strictly necessary, but I wanted to build this thing once and then never worry about it again, and screws and glue are cheap.
Even just the plywood outline without the print glued on looked pretty good. Early in the project I dithered on whether to make the thing out of plywood or foam core board. Foam core board would have been cheaper, easier to work with, and a lot lighter, but I also had doubts about its survivability. I want to use this thing for outreach for a long time to come.
To make the thing free-standing I added a kickstand in the back, made from a six-foot board and a hinge.
I used some screw-eyes and steel wire from a picture-hanging kit to add restraints to the kickstand, so it can’t open up all the way and collapse.
I didn’t want the kickstand flopping around during transit, and I also did not want the whole weight of the kickstand hanging cantilevered from the hinge when this thing is being carried horizontally, so I added a couple of blocks on either side for support, and some peel-and-stick velcro to hold the kickstand in place when it’s not being used.
I took the thing to Oakmont Outdoor School this morning and everybody loved it. I think the teachers were just as impressed as the kids. That’s Jenny Adams, the principal at Oakmont, who invited me to come speak.
This was a deeply satisfying project and it didn’t require any complex or difficult techniques. The biggest expense was the big poster print, and the most specialized piece of equipment was the jigsaw. You could save money by going black-and-white or just blowing up an outline drawing on a plotter, by scavenging the plywood instead of buying new (all my old plywood has been turned into stuff already), or by using foam core board or some other lightweight material.
Many thanks to Jenny Adams and the whole Oakmont community for giving me a chance to come speak, and for asking so many excellent questions. However much fun it was for you all, I’m pretty sure it was even more fun for me. And now I have an inconveniently gigantic Brachiosaurus humerus to worship play with!
I am about a great work
January 21, 2023
I’m also teaching in two anatomy courses and in the process of moving residences (hence bins and boxes and whatnot), so the timing’s…not great. But needs must when the devil drives.
Further bulletins as events warrant.
Dino dig birthday cake
June 5, 2022
One of the benefits of being me is that my friends often make me cool dino-themed stuff for my birthday (f’rinstance). This year, it was this dinosaur dig cake from my friend Jenny Adams. Yes, it’s a vulgar, overstudied theropod,* but I take the requisite amount of joy from how thoroughly blown apart its skeleton is. Plus, the skull and cervicals are pneumatic (in vivo, if not in choco), so it’s a least plausibly interesting (i.e., not an ornithopod), and it looks cool (i.e., not Camarasaurus).
*I’m morally obligated to thank Paul Barrett for this wonderful phrase, which I use pretty much every chance I get.
Should you want to replicate this glycemic index Chicxulub, here’s the stratigraphic breakdown, starting from the bedrock (bedchoc?):
- base layer is a regular chocolate cake,
- but with added chocolate chips,
- topped with vanilla frosting, to hold down:
- a whole package of Oreos crumbled into faux dirt
- surrounding the vanilla-flavored white chocolate dinosaur bones
Jenny made the dino bones using a set of (new, clean) plastic sand molds, like these:
You can find a zillion like ’em online by searching for ‘dinosaur sand toys’ or ‘dinosaur sand mold’.
Anyway, I can report that the excavation has been most enjoyable, but with about half the ‘quarry’ left to explore, the number of fossils recovered intact continues to hover near zero — we’ve been grinding them up to use as dietary supplements. Good thing it’s just a theropod!
My Brachiosaurus talk for Dinosaur Journey is now on YouTube
October 20, 2021
My Oct. 13 National Fossil Day public lecture, “Lost Giants of the Jurassic”, for the Museums of Western Colorado – Dinosaur Journey is now up on their YouTube channel. First 48 minutes are talk, last 36 minutes are Q&A with audience, moderated by Dr. Julia McHugh. New stuff from the 2021 field season — about which I’ll have more to say in the future — starts at about the 37-minute mark. Hit the 44-minute mark (and this and this) to find out what to do with all of the unwanted bird necks that will be floating around at the upcoming holidays.
Finally, big thanks to Brian Engh for finding our brachiosaur and for letting me use so much of his art, to John Foster, Kaelen Kay, Tom Howells, Jessie Atterholt, Thierra Nalley, and Colton Snyder for such a fun field season this year, and to Julia McHugh for giving me the opportunity to yap about one of my favorite dinosaurs!
Things to Make and Do, Part 29b: Matt’s pig skull – finished
January 17, 2021
Here’s how my pig skull turned out (prep post is here).
Verdict? I’m reasonably happy with it. As Mike wrote in the post that kicked off the “Things to Make and Do” series, “a pig skull is a serious piece of kit”. It’s big and substantial and it looks awesome sitting on the shelf. I learned a lot prepping it, and in particular I learned a couple of things that I will do differently next time:
- From now on I will cut the meat off first and grill only that, and not put the skull through the thermal stress of getting dry-cooked. Even with indirect heat, I think smoking the whole head did adversely affect the quality of the bone. The forehead and the rami of the mandibles in particular lost a little integrity. I painted the whole skull with a mix of 50% PVA (white glue, like Elmer’s) and 50% water, so it’s solid, but the surface bone is just slightly rough, I think because of degradation of the cortical bone.
- Before this I had only prepped small bones–small mammal and reptile skulls, vertebrae and long bones of domestic fowl, cannon bones and hooves of cattle. Stuff like that takes maybe an hour or two max to simmer, and to whiten, and that’s how I approached the pig skull. And it took forever, because I was doing short cycles, which meant doing a lot of them. I did a sheep skull this past holiday break, which I will post about soon, and I learned that the trick with bigger bones is just time. Simmer for 12 hours, not 2 hours, whiten for 2 or 3 nights, not just one. The sheep skull probably took more time from start to finish, but it was a lot less effort, because for much of that time it was just simmering, or soaking in dilute hydrogen peroxide.
With their deep lower jaws, pig skulls look rather lumpen in lateral view. But they look awesome in anterodorsal view, like dragon skulls. Here you can see that the prenasal bone is a little darker and less crisp than the other bones of the face. That’s because it was still ossifying from a big block of cartilage. I scraped off most of the cartilage, but not all, and what remained dried and hardened into an incredibly tough, translucent, slightly yellowish shell.
I still have two pig heads on ice. I probably won’t do anything with either of them until I get some more time off, but I am looking forward to prepping another pig skull, in part to see how much better I can do the next time. But I’m still happy to have this one. To paraphrase another line from Mike’s old post, this is something that everyone ought to do.
Edit: here are some links about cooking pig heads and prepping skulls.
- Will it Sous Vide?: The Head of a Pig (Lifehacker)
- How to Clean Animal Bones So You May Proudly Display Them in Your Home (Lifehacker)
- Why Pig’s Head Should Headline Your Next Cookout (Thrillist)
- Porchetta di Testa – Pig’s Head Roulade (West Coast Prime Meats)
Things to Make and Do, Part 29a: Matt’s pig skull – the prep
December 26, 2020
This is something I did over Thanksgiving break in 2019. I meant to blog about it sooner, but you know, 2020 and all. So here I am finally getting around to it. (Yes, I know the ruler in the above photo is the worst scale bar ever. I was, uh, making a point. Which you got. So go you!)
For reasons unknown to me, the strip of skin between the mid-snout and the ear on the right side of the head was already off when I took possession from the local butcher. But it did show the ear muscles to good advantage, as well as the parotid gland–the knobbly white thing between the eye and ear that looks like grits, or eggs, or white beans. You have a parotid gland in front of each of your ears, too (par-otid = “next to ear”), each with a duct that crosses the cheek to bring saliva into your mouth. If you push your tongue into the upper-lateral “corners” of your cheeks, you can feel the little papilla where the duct opens, and if you push against the papilla with your tongue you may feel a little saliva leak out. You also have paired submandibular and sublingual salivary glands, but those will have to wait for another day.
Here’s the head from the back, after I’d gotten the right ear off. The bluish-white hyaline cartilage over the occipital condyles is clearly visible about 2/3 of the way up from the bottom, with the faintly yellowish stump of the medulla oblongata in between, going up into the braincase. Tons of neck muscles are visible here, and maybe someday I or someone else will get around to labeling them in this photo–but it is not this day.
What was I doing here? Getting off the ears, and as much skin and subcutaneous fat as possible, in preparation for brining and smoking. I like this photo, the little piggy looks positively happy about having its skull prepped.
Right, into the bag with you then. I did the same brining and smoking routine that I did for my first smoked turkey back when–see this post for details.
And here we are about 15 hours later. Note how much the color of the meat has changed from the brining.
Time to extract the brain. I already showed a version of this photo in my post on the $1 brain-extractor (a.k.a. drain rooter, see this post), but it bears repeating: the brain is mostly lipids and if you cook the head with the brain still in it, the brain will turn into liquid fat and seep into the bones and you’ll spend the rest of your days trying to degrease the skull before you die, unloved and weeping, on a pile of rags. So no matter how you’re planning to cook the head, yoink the brain first.
Onto the grill, with a drip pan underneath, foil heat shields in place to keep the heat indirect, and foil-wrapped mesquite smoke bombs visible under the grill, right on top of the coals. This is about all I do with my grill anymore; smoking is really no more work than anything else and the results are pretty much to die for. YMMV.
Same shot an hour later and the smoking is coming along nicely. I ended up smoking this head for three hours, an hour and a half on each side.
And into the roasting pan for a few minutes’ rest at the end of the cooking. And it was cooking, not just specimen prep–we ate this pig head in lieu of a turkey for Thanksgiving, and it was amazingly delicious. One thing to note in this photo is how the temporalis fascia has pulled away from the skull at the upper left, exposing some bare bone. This would be a problem later on.
Defleshing, both to get the edible meat off, and to get as much of the rest of the soft tissue off in preparation for simmering. In this anterior view, you can see that the right side of the animal’s forehead (viewer’s upper left) got exposed during the smoking process and the bone is stained brown.
Even with the meat cooked all the way through, disarticulating the jaw took some doing, and then some follow-up meat removal. Check out the very round, almost hemispherical mandibular condyles, which fit up into the sockets of the temporomandibular joints. Birds and other reptiles mostly do it the opposite way, with rounded quadrates on the cranium that fit into articular sockets on the lower jaw.
Ready for simmering. Pro tip: if you need a really big metal pot in which to simmer skulls or other large osteological specimens, but you don’t want to go bankrupt, look for a tamale-steaming pot. They’re comparatively thin-walled and lightweight, but still plenty sturdy for just about any application you are likely to think of.
Our kitty, Moe, helped with the clean-up of the roasting pan.
The first simmer. At this remove, I don’t remember how many rounds of simmering I did, but it was at least two, maybe three.
Post-simmer, I put the skull into a sink-full of warm, soapy water for a defleshing. Notable bits you can see on the right side of the photo are the ridged surface of the palate (about 7:00 on the plate), the long straight cartilage of the nasal septum (going vertically up the right side of the plate), and the incisors at the extreme upper right, sitting on the edge of the sink. Most of the incisors fell out during the wash, which was fine, because most of them were horribly stained from the smoking process and would require a lot of scrubbing and bleaching to get back to a nice and natural-looking white.
The condition after the first simmer. You can see that the supraorbital foramina, on the forehead between the eyes, still have goop in them. This was true of pretty much all of the nerve and blood vessel passages. It took a lot of time, some ingenuity, bamboo barbeque skewers, and running water this way and that to flush out all of that crud. And the bones are still weird colors at this stage, pre-whitening, especially the groady dark patches on the forehead. It wasn’t the areas of bone that were directly exposed to smoke that were the problem, it was the areas just adjacent where the periosteum cooked against the bone.
Same stage, left lateral view. Note the empty sockets for the incisors, and the infraorbital foramen (above the upper teeth and about a third of the way between eye socket and the nose), which on this side is divided in two by a strut of bone. There’s another gross dark patch on the back of the zygomatic arch. All of those took pretty aggressive scrubbing to remove.
Back into the pot for another simmer. The perforated plate at the bottom sits on a lip of metal about three inches above the bottom of the pot so you can steam tamales with this thing. I used it to keep the bones off the bottom of the pot so they’d have no chance of getting scorched.
Here’s a significant jump forward in time. By this point I’d degreased and whitened the skull by soaking it in dilute hydrogen peroxide (I use the cheap stuff from the dollar store down the street, and it works fine), applied glue to several of the skull sutures that were threatening to come apart, and epoxied the prenasal bone back into position between the nasal bones above and the premaxillary bones below. The prenasal bone is a pretty cool structure, you can see it in other views (including a cross-section!) in this post. I also glued the incisors back in at this stage.
Believe it or not, this was the largest skull I had ever prepped myself–the largest osteological preparation of any kind, in fact–and it was a lot more work than I anticipated. But the effort was worth it, and now I have a really cool pig skull on my bookcase. I’ll show the finished skull in a follow-up post (no, really, I will!). EDIT: And I did!
For other posts on pig skulls, see:
Make a scale model Brachiosaurus humerus from chicken bones
February 9, 2020
This is the Jurassic World Legacy Collection Brachiosaurus. I think it might be an exclusive at Target stores here in the US. It turns up on other sites, like Amazon and eBay, but usually from 3rd-party sellers and with a healthy up-charge. Retails for 50 bucks. I got mine for Christmas from Vicki and London. Here’s the link to Target.com if you want to check it out (we get no kickbacks from this).
I thought it would be cool to leverage this thing at outreach events to talk about the new Brachiosaurus humerus that Brian Engh found last year, which a team of us got out of the ground and safely into a museum last October (full story here). But I needed a Brachiosaurus humerus, so I made one, and in this post I’ll show you how to do the same, for next to no money.
Depending on what base you start with and what materials you use, you could build a scale model of a Brachiosaurus humerus at any size. I wanted one that would match the JWLC Brach, so I started by taking some measurements of that. Here’s what I got:
Lengths
- Head: 45mm
- Neck: 455mm (x 20 = 9.1m = 29’10”)
- Torso: 320mm
- Tail: 320mm
- Total: 1140 (x 20 = 22.8m = 74’10”)
Heights
- Max head height: 705mm (x 20 = 14.1m = 46’3″)
- Withers height: 360mm (x 20 = 7.2m = 23’7″)
The neck length, total length, and head height are pretty close to the mounted Giraffatitan in Berlin. The withers are a little high, as is the bottom of the animal’s belly. I suspect that the limbs on the model are oversized by about 10%. Nevertheless, the numbers say this thing is roughly 1/20 scale.
The largest humeri of Brachiosaurus and Giraffatitan are 213cm, which is about 3mm shy of 7 feet. So a 1/20 scale humerus should be 106.5mm, or 4.2 inches, or four-and-a-quarter if you want a nice, round number.
Incidentally, Chris Pratt is 6’2″ (74 inches), and the Owen Grady action figure is 3.75″, which is 1/20 of 6’3″. So the action figure, the Brachiosaurus toy highly detailed scientific model, and a ~4.2″ humerus model will all be more or less in scale with each other.
I used a chicken humerus for my base. The vast majority of chickens in the US are slaughtered at 5 months, so they don’t get nearly big enough for their humeri to be useful for this project. Fortunately, there’s a pub in downtown Claremont, Heroes & Legends, that has giant mutant chicken hot wings, so I went there and collected chicken bones in the guise of a date. The photo above shows three right humeri (on the left) and one left humerus (on the right) after simmering and an overnight degreasing in a pot of soapy water. I used the same bone clean-up methods as in this post.
What should you do if you don’t have access to giant mutant chicken wings? My method of Brachio-mimicry involves some sculpting, so any reasonably straight bone that bells out a bit at the ends would work. You could use a drumstick in a pinch. Here are my humeri whitening in a tub of 3% hydrogen peroxide from the dollar store down the street.
Brachiosaurid humeri vary somewhat but they all have certain features in common. Here’s the right humerus of Vouivria, modified from Mannion et al. (2017: fig. 19) to show the features of interest to brachiosaur humerus-sculptors. The arrows on the far left point to a couple of corners, one where the deltopectoral crest (dpc in the figure) meets the proximal articular surface, and the other where the articular surface meets the long sweeping curve of the medial border of the humeral shaft.
Here’s a more printer-friendly version of the same diagram. Why did I use Vouivria for this instead of one of the humeri of Brachiosaurus itself? Mostly because it’s a complete humerus for which a nice multi-view was available. Runner-up in this category would have to go to the humerus of Pelorosaurus conybeari figured by Upchurch et al. (2015: fig. 18) in the Haestasaurus paper–here’s a direct link to that figure.
I knew that I’d be doing some sculpting, and I wanted a scale template to work off of, so I made these outlines from the Giraffatitan humerus figured by Janensch (1950) and reproduced by Mike in this post (middle two), and from the aforementioned Pelorosaurus conybeari humerus shown by Mike in this post (outer two). I scaled this diagram so that when printed to fill an 8.5×11 piece of printer paper, the humerus outlines would all be 4.25″–the same nice-round-number 1/20 scale target found above. Here’s a PDF version: Giraffatitan and Pelorosaurus humeri outlines for print.
Here’s the largest of my giant mutant chicken humeri, compared to the outlines. The chicken humerus isn’t bad, but it’s too short for 1/20 scale, the angles of the proximal and distal ends are almost opposite what they should be, and the deltopectoral crest is aimed out antero-laterally instead of facing straight anteriorly. Modification will be required!
Here’s my method for lengthing the humerus: I cut the midshaft of another humerus out, and swapped it in to the middle of the prospective Brachiosaurus model humerus.
To my immense irritation, I failed to get a photo of the lengthened humerus before I started sculpting on it. In the first wave of sculpting, I built up the proximal end and the deltopectoral crest, but missed some key features. On the right, I glued the proximal and distal ends of the donor humerus together; I might make this into a Haestasaurus humerus in the future.
I should mention my tools and materials. I have a Dremel but it wasn’t charged the evening I sat down to do this, so I made all the humerus cuts with a small, cheap hacksaw. I used superglue (cyanoacrylate or CA) for quick joins, and white glue (polyvinyl acetate or PVA) to patch holes, and I put gobs of PVA into the humeral shafts before sealing them up. For additive sculpting I used spackling compound, same stuff you use to patch holes in walls and ceilings, and for reductive sculpting I used sandpaper. I got most of this stuff from the dollar store.
Here we are after a second round of sculpting. The proximal end has its corners now, and the distal end is more accurately belled out, maybe even a bit too wide. It’s not a perfect replica of either the Giraffatitan or Pelorosaurus humeri, but it got sufficiently into the brachiosaurid humerus morphospace for my taste. A more patient or dedicated sculptor could probably make recognizable humeri for each brachiosaurid taxon or even specimen. I deliberately left it a bit rough in hopes that it would read as timeworn, fractured, and restored when painted and mounted. Again, a real sculptor could make some hay here by putting in fake cracks and so on.
The cheap spackling compound I picked up did not harden as much as some other I have used in the past. I had planned on sealing anyway before I painted, and for porous materials a quick, cheap sealant is white glue mixed with water. Here that coat of diluted PVA is drying, and I’m holding up a spare chicken humerus to show how far the model humerus has come.
Before painting, I drilled into the distal end with a handheld electric drill, and used a bamboo barbeque skewer as a mounting rod and handle. I hit it with a couple of coats of gray primer, then a couple of coats of black primer the next day. I could have gotten fancier with highlights and washes and so on, but I was scrambling to get this done for a public outreach event, in an already busy week.
And here’s the finished-for-now product. A couple of gold-finished cardboard gift boxes from my spare box storage gave their lids to make a temporary pedestal. When I get a version of this model that I’m really happy with, either by hacking further on this one or starting from scratch on a second, I’d love to get a wooden or stone trophy base with a little engraved plaque that looks like a proper museum exhibit, and replace the bamboo skewer with a brass rod. But for now, I’m pretty happy with this.
The idea of making dinosaurs out of chicken bones isn’t original with me. I was inspired by the wonderful books Make Your Own Dinosaur Out of Chicken Bones and T-Rex To Go, both by Chris McGowan. Used copies of both books can be had online for next to nothing, and I highly recommend them both.
If this post helps you in making your own model Brachiosaurus humerus, I’d love to see the results. Please let me know about your model in the comments, and happy building!
References
- Janensch, Werner. 1950. Die Wirbelsaule von Brachiosaurus brancai. Palaeontographica (Suppl. 7) 3: 27-93.
- (2017) The earliest known titanosauriform sauropod dinosaur and the evolution of Brachiosauridae. PeerJ 5:e3217 https://doi.org/10.7717/peerj.3217
- Upchurch, Paul, Philip D. Mannion and Micahel P Taylor. 2015. The Anatomy and Phylogenetic Relationships of “Pelorosaurus” becklesii (Neosauropoda, Macronaria) from the Early Cretaceous of England. PLoS ONE 10(6):e0125819. doi:10.1371/journal.pone.0125819
If you followed along with the last post in this series, you now have some bird vertebrae to play with. Here are some things to do with them.
1. Learn the parts of the vertebrae, and compare them with those of other animals
Why are we so excited about bird vertebrae around here? Mostly because birds are reasonably long-necked living dinosaurs, and although their vertebrae differ from those of sauropods in relative proportions, all of the same bits are present in roughly the same places. If you know the parts of a bird vertebra and what each one does, you have a solid foundation for inferring the functions of sauropod vertebrae. Here’s a diagram I made for my SVP poster with Kent Sanders way back in 1999. I used an ostrich vertebra here but you should be able to find the same features in a cervical vertebra of just about any bird.
These are both middle cervical vertebrae in right lateral view. A middle cervical vertebra of a big ostrich will be between 3 and 4 inches long (7.5-10 cm), and one from a big brachiosaur like Giraffatitan will be about ten times longer.
I should do a whole post on neck muscles, but for now see this post and this paper.
2. Put the vertebrae in order, and rearticulate them
It is often useful to know where you are in the neck, and the only way to figure that out is to determine the serial position of the vertebrae. Here’s an articulated cervical series of a turkey in left lateral view, from Harvey et al. (1968: pl. 65):
Harvey’s “dorsal spine” is the neural spine or spinous process, and his “ventral spine” is the carotid process. The “alar process” is a sort of bridge of bone connecting the pre- and postzygapophyses; you can see a complete version in C3 in the photo below, and a partial version in C4.
Speaking of that photo, here’s my best attempt at rearticulating the vertebrae from the smoked turkey neck I showed in the previous post, with all of the vertebrae in left dorsolateral view.
These things don’t come with labels and it can take a bit of trial and error to get them all correctly in line. C2 is easy, with its odd articular surface for the atlas and narrow centrum with a ventral keel. Past that, C3 and C4 are usually pretty blocky, the mid-cervicals are long and lean, and then the posterior cervicals really bulk out. Because this neck section had been cut before I got it, some of the vertebrae look a little weird. Somehow I’m missing the front half of C6. The back half of C14 is also gone, presumably still stuck to the bird it went with, and C7 and C12 are both sectioned (this will come in handy later). I’m not 100% certain that I have C9 and C10 in the right order. One handy rule: although the length and neural spine height change in different ways along the column, the vertebrae almost always get wider monotonically from front to back.
And here’s the duck cervical series, in right lateral view. You can see that although the specific form of each vertebra is different from the equivalent vert in a turkey, the same general rules apply regarding change along the column.
Pro tip: I said above that these things don’t come with labels, but you can fix that. Once you have the vertebrae in a satisfactory order, paint a little dot of white-out or gesso on each one, and use a fine-point Sharpie or art pen to write the serial position (bone is porous and the white foundation will keep the ink from possibly making a mess). You may also want to put the vertebrae on a string or a wire to keep them in the correct order, but even so, it’s useful to have the serial position written on each vertebra in case you need to unstring them later.
3. Look at the air spaces
One nice thing about birds is that all of the species that are readily commercially available have pneumatic traces on and in their vertebrae, which are broadly comparable to the pneumatic vertebrae of sauropods.
The dorsal vertebrae of birds are even more obviously similar to those of sauropods than are the cervicals. These dorsal vertebrae of a duck (in left lateral view) show a nice variety of pneumatic features: lateral fossae on the centrum (what in sauropods used to be called “pleurocoels”), both with and without foramina, and complexes of fossae and foramina on the neural arches. Several of the vertebrae have small foramina on the centra that I assume are neurovascular. One of the challenges in working with the skeletal material of small birds is that it becomes very difficult to distinguish small pneumatic foramina and spaces from vascular traces. Although these duck vertebrae have small foramina inside some of the lateral fossae, the centra are mostly filled with trabecular, marrow-filled bone. In this, they are pretty similar to the dorsal vertebrae of Haplocanthosaurus, which have fossae on the neural arches and the upper parts of the centra, but for which the ventral half of each centrum is a brick of non-pneumatic bone. For more on distinguishing pneumatic and vascular traces in vertebrae, see O’Connor (2006) and Wedel (2007).
This turkey cervical, in left posterolateral view, shows some pneumatic features to nice advantage. The lateral pneumatic foramina in bird cervicals are often tucked up inside the cervical rib loops where they can be hard to see and even harder to photograph, but this one is out in the open. Also, the cervicals of this particular turkey have a lot of foramina inside the neural canal. In life these foramina are associated with the supramedullary diverticula, a set of air-filled tubes that occupy part of the neural canal in many birds — see Atterholt and Wedel (2018) for more on this unusual anatomical system. The development of foramina inside the neural canal seems to be pretty variable among individuals. In ostriches I’ve seen individuals in which almost every cervical has foramina inside the canal, and many others with no foramina. For turkeys it’s even more lopsided in my experience; this is the first turkey in which I’ve found really clear pneumatic foramina inside the neural canals. This illustrates one of the most important aspects of pneumaticity: pneumatic foramina and cavities in bones show that air-filled diverticula were present, but the absence of those holes and spaces does not mean that diverticula were absent. Mike and I coined the term “cryptic diverticula” for those that leave no diagnostic traces on the skeleton — for more on that, see the discussion section in Wedel and Taylor (2013b).
Finally, it’s worth taking a look at the air spaces inside the vertebrae. Here’s a view into C12 of the turkey cervical series shown above. The saw cut that sectioned this neck happened to go through the front end of this vertebra, and with a little clean-up the honeycomb of internal spaces is beautifully displayed. If you are working with an intact vertebra, the easiest way to see this for yourself is to get some sandpaper and sand off the front end of the vertebra. It only takes a few minutes and you’ll be less likely to damage the vertebrae or your fingers than if you cut the vertebra with a saw. Similar complexes of small pneumatic cavities are present in the vertebrae of some derived diplodocoids, like Barosaurus (see the lateral view in the middle of this figure), and in most titanosauriforms (for example).
I have one more thing for you to look for in your bird vertebrae, and that will be the subject of the next installment in this series. Stay tuned!
References
- Atterholt, J., and Wedel, M. 2018. A CT-based survey of supramedullary diverticula in extant birds. 66th Symposium on Vertebrate Palaeontology and Comparative Anatomy, Programme and Abstracts, p. 30 / PeerJ Preprints 6:e27201v1
- Harvey, E.B., Kaiser, H.E. and Rosenberg, L., 1968. An atlas of the domestic turkey (Meleagris gallopavo). Myology and osteology. U.S. Atomic Energy Commission, Germantown, Maryland, 247 pp.
- O’Connor, P.M. 2006. Postcranial pneumaticity: an evaluation of soft-tissue influences on the postcranial skeleton and the reconstruction of pulmonary anatomy in archosaurs. Journal of Morphology 267:1199-1226.
- Wedel, M.J. 2007a. What pneumaticity tells us about ‘prosauropods’, and vice versa. Special Papers in Palaeontology 77:207-222.
- Wedel, Mathew J., and Michael P. Taylor. 2013. Caudal pneumaticity and pneumatic hiatuses in the sauropod dinosaurs Giraffatitan and Apatosaurus.PLOS ONE 8(10):e78213. 14 pages. doi:10.1371/journal.pone.0078213
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!
Sauropod Vertebra Picture of the Week 
