For my birthday this year, my wife bought me the newish Lego kit Natural History Museum 10326. (Well: actually she bought me a Chinese knock-off for 1/3 the price, but that’s not the point.) It’s a lovely kit and I had a great time building it.
One of the exhibits that you build for the museum is a sauropod skeleton — recognizably a brachiosaur. But as previously documented on this blog, I also have a much larger Lego brachiosaur, built from the piece of the kit Dinosaur Fossils 21320. (That one was also a present from Fiona!)
Here they are, side by side.
So which brachiosaur is more accurately to scale?
Lego is often considered to be in 42:1 scale, based on minifigure height of about 4 cm relative to a typical adult human height of about 1.68 m. (5 feet 6 inches).
I measured the big brachiosaur at 37 cm high from the top of its plinth to the top of the head. At 42:1 scale, that’s 15.54 m. The smaller one is 15 cm tall from plinth to head, which at 42:1 scale is 6.30 m.
The real Giraffatitan mount in the Museum für Naturkunde Berlin is 13.27 m tall (Taylor and Wedel 2013: caption to figure 1). That means that the larger of the two Lego models is much closer to being the right size, relative to the minifigs, than the small one is.
But wait: famously, the Giraffatitan fibula HMN XV2 is 134 cm long compared with 119 cm for the fibula of HMN SII (= MB.R.2181, the mounted specimen) (Janensch 1961: table 16). That’s 1.126 times as long, which indicates it belonged to an animal that stood 13.27 x 1.126 = 14.94 m tall.
That’s 96% the scaled size of the Lego Giraffatitan — which, given the hand-waving involved in the various scalings here, is as near to identical as makes no difference.
In conclusion, m’lud, the large Lego Giraffatitan in the photo above is almost exactly the right size for the largest known individual of that genus, relative to the minifigs and indeed the actual museum.
References
- Janensch, Werner. 1961. Die Gliedmaszen und Gliedmaszengurtel der Sauropoden der Tendaguru-Schichten. Palaeontographica, suppl. 7(3):177-235.
- Taylor, Michael P., and Mathew J. Wedel. 2013c. The effect of intervertebral cartilage on neutral posture and range of motion in the necks of sauropod dinosaurs. PLOS ONE 8(10):e78214. 17 pages. doi: 10.1371/journal.pone.0078214
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.
Why were prehistoric sea creatures so tiny?
March 12, 2024
My friend Toby Lowther wrote to me back in December to ask this question:
As far as I understand it, the general rule for extant species is that it’s much easier to get much bigger underwater than on land, due to the role that water plays in supporting large bodies. But as was recently pointed out to me by a friend, sauropods seem to be much, much larger than any known or recorded prehistoric sea creatures — and, in fact, despite sauropods being much larger than any modern megafauna, plesiosaurs, mosasaurs, etc. seem to be smaller than, say, blue whales. Is there a current theory/explanation as to why? Why you have these various periods where land megafauna ends up larger than any contemporaneous sea megafauna, and why despite dinosaurs getting so big, the largest prehistoric sea megafauna are smaller than the largest modern whales?
It’s strange, isn’t it? The last I knew, Shonisaurus was the largest ichthyosaur, at about 20 m and 50 tonnes, and this is considerably bigger than any plesiosaur or mosasaur I know of. It’s up the sperm-whale size category, but not even close to the bigger baleen whales. Why not?
Meanwhile, there is solid evidence for sauropods massing more than this on land — and less solid but I think still good evidence for them getting at least twice this heavy.
So what’s the deal with all those Mesozoic sea creatures being so tichy compared with terrestrial beasts that had so many more size-related problems to deal with?
Speak, O commenters! We’re listening.
Giant titanosaurs were just ridiculous
September 13, 2023
Here’s Mike with the cast dorsal vertebra of Argentinosaurus that’s on display at the LACM. I tried to get myself equidistant from both Mike and the vert when I took the photo, but even I couldn’t quite believe it when I looked at it on my laptop. Surely, I thought, there must be some subtle foreshortening going on, to make the Argentinosaurus vert look bigger than it is. So I did some cypherin’.
The LACM dorsal has a clearly reconstructed centrum, and in all other ways, including the position of the parapophyses and the slightly reclined neural spine, it’s a good match for this vertebra figured in Bonaparte and Coria (1993: fig. 2). The scale bar there is 50cm. In my scan, it’s 242 pixels, and the total height of the vertebra is 800 pixels, or 1.65 meters, or 5’5″. Mike’s about 1.8 meters, and the photo confirms that he’s a little taller than the vertebra, but not by much. I think that photo is a pretty accurate representation of the size of the vertebra relative to a normal human being Mike.
Which is kinda crazy. I’m no stranger to big vertebrae — my first project turned out to be Sauroposeidon, and I’ve spent more time looking at Giraffatitan and Supersaurus verts than is probably healthy — but damn. Even I am used to big vertebrae that are still smaller than a person. Fair play to you, Argentinosaurus.
(I’m contractually obligated to remind everyone that despite frequent claims to the contrary, Argentinosaurus is still the largest dinosaur known from measurable bones.)
Reference
Bonaparte, J.F. and Coria, R.A. 1993. Un nuevo y gigantesco saurópodo titanosaurio de la Formación Río Limay (Albiano-Cenomaniano) de la Provincia del Neuquén, Argentina. Ameghiniana 30(3):271-282.
No-one knows whether or not a neutral-tasting nutrient-sludge diet leads to enormous weight loss
February 15, 2023
I recently discovered the blog Slime Mold Time Mold, which is largely about the science of obesity — a matter of more than academic interest to me, and if I may say to, to Matt.
I discovered SMTM through its fascinating discussions of scurvy and citrus-fruit taxonomy. But what’s really been absorbing me recently is a series of twenty long, detailed posts under the banner “A Chemical Hunger“, in which the author contests that the principle cause of the modern obesity epidemic is chemically-induced changes to the “lipostat” that tells our bodies what level of mass to maintain.
I highly recommend that you read the first post in this series, “Mysteries“, and see what you think. If you want to read on after that, fine; but even if you stop there, you’ll still have read something fascinating, counter-intuitive, well referenced and (I think) pretty convincing.
Anyway. The post that fascinates me right now is one of the digressions: “Interlude B: The Nutrient Sludge Diet“. In this post, the author tells us about “a 1965 study in which volunteers received all their food from a ‘feeding machine’ that pumped a ‘liquid formula diet’ through a ‘dispensing syringe-type pump which delivers a predetermined volume of formula through the mouthpiece'”, but they were at liberty to choose how many hits of this neutral-tasting sludge they took.
This study had an absolutely sensational outcome: among the participants with healthy body-weight, the amount of nutrient sludge that they chose to feed themselves was almost exactly equal in caloric content to their diets before the experiment. But the grossly obese participants (weighing about 400 lb = 180 kg), chose to feed themselves a tiny proportion of their usual intake — about one tenth — and lost an astonishing amount of weight. All without feeling hunger.
Please do read the Slime Mold Time Mold write-up for the details. But I will let you in right now on the study’s very very significant flaw. The sample-size was two. That is, two obese participants, plus a control-group of two healthy-weight individuals. And clearly whatever conclusion we can draw from a study of that size is merely anecdotal, having no statistical power worth mentioning.
And now we come to the truly astonishing part of this. It seems no-one has tried to replicate this study with a decent-sized sample. The blog says:
If this works, why hasn’t someone replicated it by now? It would be pretty easy to run a RCT where you fed more than five obese people nutrient sludge ad libitum for a couple weeks, so this means either it doesn’t work as described, or it does work and for some reason no one has tried it. Given how huge the rewards for this finding would be, we’re going to go with the “it doesn’t work” explanation.
In a comment, I asked:
OK, I’ll bite. Why hasn’t anyone tried to replicate the astounding and potentially valuable findings of these studies? It beggars belief that it’s not been tried, and multiple times. Do you think it has been tried, but the results weren’t published because they were unimpressive? That would be an appalling waste.
The blog author replied:
Our guess is that it simple hasn’t been tried! Academia likes to pretend that research is one-and-done, and rarely checks things once they’re in the literature. We agree, someone should try to replicate!
I’m sort of at a loss for words here. How can it possibly be that, 58 years after a pilot study that potentially offers a silver bullet to the problem of obesity, no-one has bothered to check whether it works? I mean, the initial study is so old that Revolver hadn’t been released. Yet it seems to have just lain there, unloved, as the Beatles moved on through Sergeant Pepper, the White Album, Abbey Road et al., broke up, pursued their various solo projects, died (50% of the sample) and watched popular music devolve into whatever the heck it is now.
Why aren’t obesity researchers all over this?
The ludicrous sizes of world-record individuals
February 6, 2023
This recent news story tells of a cane toad found in Australia that weighs six pounds. Here’s the photo, because it’s too good not to include:
Kylee Gray, a ranger with the Queensland Department of Environment and Science, holds a giant cane toad, Thursday, Jan. 12, 2023, near Airlie Beach, Australia. “We believe it’s a female due to the size, and female cane toads do grow bigger than males. When we returned to base, she weighed in at 2.7kg, (5.95 lbs) which could be a new record”, said Gray. (Queensland Department of Environment and Science via AP)
I am no cane-toad expert, so I am only going on what this news report had to say, but apparently the average weight of a cane toad is about one pound. So this new world-record individual masses six times as much as a typical adult.
Mature male saltwater crocodiles Crocodylus porosus are typically about 4.5 m long, but the world-record verified skull length is 76 cm long indicating a total length of about 7 m. Having a length 1.56 times that of a typical individual, this beast would have massed 1.56^3 = 3.75 times as much.
There may be less variance in mammal sizes. The world-record elephant Satao massed about 11 tonnes. That’s about double the typical adult African elephant mass, which is various reported as 5 or 6 tonnes.
Now think about sauropod sizes. We have a bunch of big Diplodocus specimens all measuring on the order of 25 m in length, and massing perhaps 15 tonnes. If world-record individuals compared to these as world-record elephants do, there would have been Diplodocus individuals of twice that mass (30 tonnes); if they compared as crocs do, we should expect giant specimens massing 3.75 times as much (56 tonnes); and if they compared as cane toads do, then the factor of 6 would give us giant Diplodocus individuals massing 90 tonnes.
All of this is speculative of course — wildly so — because we have such tiny samples of Diplodocus compared with the three extant species discussed above. It’s not remotely surprising that the ten or so specimens we have don’t include a freak like this. But there’s a good chance they were out there.
Oh, and for Brachiosaurus, of which known individuals massed perhaps 30 tonnes, it’s not unreasonable to imagine giant individuals massing 60, 112 or gulp! 180 tonnes. Yes, the imagination balks at the idea of a 180-tonne land animal: but that alone is not reason enough to discount the possibility.
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.
Why are elephants so small?
April 13, 2022
I have long intended to write a paper entitled Why Elephants Are So Small, as a companion piece to Why Giraffes Have Short Necks (Taylor and Wedel 2013). I’ve often discussed this project with Matt, usually under the acronym WEASS, and its substance has come up in the previous post, and especially Mickey Mortimer’s comment:
I think it would be interesting to read a study on that — the order in which various factors restrict body size without transformative adaptations. Similarly, what the differences would be for an aquatic animal like a whale.
That is exactly what the WEASS project was supposed to consist of: a list of many candidate limitations on how big animals can get, some rough attempt to quantify their Big-O behaviour, some discussion of which factors seems to limit the sizes of modern terrestrial animals, and how dinosaurs (especially sauropods) worked around those limitations.
(Whales are different. I have in my mind a half-formed notion for a third paper, completing the trilogy, with a title along the lines of Why Whales Are Dirty Cheaters.)
What are those candidate limitations? Off the top of my head:
Biomechanical:
- Bone strength
- Cartilage strength
- Cartilage thickness
- Muscle strength
- Nerve length and conduction time
Metabolic:
- Blood pressure: column height and capillary length
- Lung capacity
- Tracheal dead space
- Digestive efficiency
- Metabolic overheating
Those are just some of the physical limits. There is anecdotal evidence that elephants are not very close to their mechanical limits in their usual behaviour: they could get bigger, and still work mechanically. (Follow the link at the start of this paragraph. You will thank me.)
There are plenty of other factors that potentially limit organism size, including:
Behavioural:
- Feeding rate
- Ability to navigate dense environments
- Predator avoidance with limited athleticism
- Difficulties in mating
Ecological:
- Territory requirement
- Time taken to reach reproductive maturity
- Reproductive rate
- Birth size
- Lack of selection pressure: when there are no predators bigger than a lion, why would elephants need to evolve larger size?
I’m sure I am missing loads. Help me out!
I am haunted by something Matt wrote a while back when we were discussing this — talking about how alien sauropods are, and how easily we slip into assuming mammal-like paradigms.
We are badly hampered by the fact that all of the 250kg+ land animals are mammals. We only get to see one way of being big, and it’s obviously not the best way of being big. Our perceptions of how hard it is to be big are shaped by the animals that are bad at it.
So having written this blog post, I am wondering whether it’s time to breathe life back into this project, started in 2009 and repeatedly abandoned.
Consider a small sauropod of length x, as shown on the left above. Its mass is proportional to x cubed, it stands on leg bones whose cross-sectional area is x squared, and it ingests food through a gullet whose cross-sectional area is x squared. Now consider a larger sauropod of length 2x, as shown on the right above. Its mass is proportional to 2x cubed = 8x, it stands on leg bones whose cross-sectional area is 2x squared = 4x, and it ingests food through a gullet whose cross-sectional area is 2x squared = 4x. The bigger sauropod has to carry proportionally twice as much mass on its leg bones, and ingest proportionally twice as much food through its gullet. (Similarly, a 104-foot tall gorilla, 20 times as tall as a real one, is only 400 times as strong but 8000 times as heavy — which is why we can’t have Skull Island.)
In practice, big animals tend to have adaptations such as thicker limb bones that mean the numbers aren’t quite as bad as this, but the principal holds: the bigger an animal gets, the worse the problems imposed by scaling. It’s not possible to “solve” this problem because so many biological properties scale this way. Something is always the limiting factor. Suppose it were leg-bones or gullet. If somehow a hypothetical ultra-sauropod evolved extra thick leg-bones and gullet, scaling of respiration would suffocate it, or scaling of digestion would starve it, or scaling of heat-loss through the skin would boil it. The fundamental reason that you can’t just scale an animal up is that some parts of its function scale with volume while most — respiration, digestion, etc. — scale with surface area.
Equatorial Minnesota on Alamosaurus
February 21, 2021
Figure 3. BIBE 45854, articulated series of nine mid and posterior cervical vertebrae of a large, osteologically mature Alamosaurus sanjuanensis. Series is estimated to represent the sixth to fourteenth cervical vertebrae. A, composite photo-mosaic of the cervical series in right lateral view; identification of each vertebra indicated by C6 to C14, respectively. B, line drawing based on the photo-mosaic in A. C, line drawing in B with labels shown and vertebral fossae indicated by solid grey fill; cross-hatching represents broken bone surfaces and reconstructive material. Abbreviations: C, cervical vertebra; cdf, centrodiapophyseal fossa; clf, centrum lateral fossa; pocdf, postzygapophyseal centrodiapophyseal fossa; prcdf, prezygapophyseal centrodiapophyseal fossa; prcdf1, dorsal prezygapophyseal centrodiapophyseal fossa; prcdf2, ventral prezygapophyseal centrodiapophyseal fossa; sdf, spinodiapophyseal fossa; spof, spinopostzygapophyseal fossa; sprf, spinoprezygapophyseal fossa. (Tykoski and Fiorillo 2016)
Have you been reading Justin Tweet’s series, “Your Friends the Titanosaurs“, at his awesomely-named blog, Equatorial Minnesota? If not, get on it. He’s been running the series since June, 2018, so this notice is only somewhat grotesquely overdue. The latest installment, on Alamosaurus from Texas and Mexico, is phenomenal. I have never seen another summary or review that pulled together so much of the relevant literature and explained it all so well. Seriously, that blog post deserves to be a review paper; it could be submitted pretty much as-is, although it would be even better with his two other Alamosaurus posts integrated (this one, and this one). It’s great work, is what I’m saying, and it needs to be acknowledged.
In particular, I was struck by the note by Anonymous in 1941 on the discovery of a cervical vertebra 1.2 meters long. I’d never heard of that ref, and I’ve never seen that vert, but at 120cm it would be in the top 7 longest cervical vertebrae on the planet (see the latest version of the list in this post), narrowly beating out the 118-cm cervical of Puertasaurus. In fairness, the preserved cervical of Puertasaurus is probably a posterior one, and more anterior cervicals might have been longer. Then again, in the big Alamosaurus neck the longest verts are pretty darned posterior, so…we need more Puertasaurus.
EDIT a few hours later: Thanks to the kind offices of Justin Tweet, I’ve now seen Anonymous (1941), and the exact wording is, “A single vertebra, or neck joint bone, is three feet across, only two inches less than four feet long, and in its present fossilized state weighs 600 pounds.” ‘Two inches less than four feet long’ is 46 inches or a hair under 117cm, which puts the supposed giant cervical just behind Puertasaurus after all, but still firmly in the top 10. And depending on how one interprets the passage in Anonymous (1941), it might not have been any bigger than BIBE 45854–see this comment for details.
Big cervical showdown. From the top left: BYU 9024, originally referred to Supersaurus but more likely representing a giant Barosaurus (137cm); the single available cervical of Puertasaurus (118cm); a world-record giraffe neck (2.4m); Alamosaurus referred cervical series BIBE 45854, longest centra are ~81cm; Sauroposeidon holotype OMNH 53062, longest centrum is 125cm. This image makes it very clear that whatever Sauroposeidon was doing, it was a way different thing from Alamosaurus.
Crucially, the longest vertebrae in the BIBE 45854 series are about 80 or 81 cm long, which means that a 1.2-meter cervical would be half again as large. That is a pretty staggering thought, and that individual of Alamosaurus–assuming it was the same taxon as BIBE 45854, and not some other, longer-necked critter–would definitely be a contender for the largest sauropod of all time.
Illustrations here are of the big Alamosaurus cervical series from Big Bend, which was comprehensively described by Ron Tykoski and Tony Fiorillo in 2016, and which we have covered in these previous posts:
- How big was Alamosaurus?
- Going to see the big mounted Alamosaurus next week
- BIBE 45854, the giant Alamosaurus cervical series from Big Bend, Texas
References
- Anonymous. 1941. Find dinosaur neck bone nearly four feet long. The Science News-Letter 39(1):6–7.
- Tykoski, R.S. and Fiorillo, A.R. 2016. An articulated cervical series of Alamosaurus sanjuanensis Gilmore, 1922 (Dinosauria, Sauropoda) from Texas: new perspective on the relationships of North America’s last giant sauropod. Journal of Systematic Palaeontology 15(5):339-364.
Sauropod Vertebra Picture of the Week 
