October 7, 2015
Well, I’m a moron again. In the new preprint that I just published, I briefly discussed the six species of sauropod for which complete necks are known — Camarasaurus lentus (but it’s a juvenile), Apatosaurus louisae (but the last three and maybe C5 are badly damaged), Mamenchisaurus hochuanensis (but all the vertebrae are broken and distorted), Shunosaurus lii, Mamenchisaurus youngi and Spinophorosaurus nigerensis.
I did have the wit to say, in the Author Comment:
Although I am submitting this article for formal peer-review at the same time as publishing it as a preprint, I also solicit comments from readers. In particular I am very keen to know if I have missed any complete sauropod necks that have been described in the literature. In the final version of the manuscript, I will acknowledge those who have offered helpful comments.
Happily, several people have taken me up on this (see the comments on the preprint), but one suggestion in particular was a real D’oh! moment for me. Oliver Demuth reminded me about Kaatedocus — a sauropod that we SV-POW!sketeers love so much that it has its own category on our site and we’ve held it up as an example of how to illustrate a sauropod specimen. More than that: we have included several illustrations of its vertebrae in one of our own papers.
Aaanyway … the purpose of this post is just to get all the beautiful Kaatedocus multiview images up in one convenient place. They were freely available as supplementary information to the paper, but now seem to have vanished from the publisher’s web-site. I kept copies, and now present them in the conveniently viewable JPEG format (rather the download-only TIFF format of the originals) and with each image labelled with its position in the column.
Please note, these images are the work of Tschopp and Mateus (2012) — they’re not mine!
C15 (and the rest of the skeleton) is missing, which makes this a very nearly, but not quite, complete sauropod neck.
- Tschopp, Emanuel, and Octávio Mateus. 2012. The skull and neck of a new flagellicaudatan sauropod from the Morrison Formation and its implication for the evolution and ontogeny of diplodocid dinosaurs. Journal of Systematic Palaeontology 11(7):853-888. doi:10.1080/14772019.2012.746589
October 3, 2015
For a forthcoming minor paper, I need a good-quality scan of Hatcher’s 1901 monograph on Diplodocus carnegii — specifically, plate VI, the photographs of the cervicals in posterior view.
Here is the best scan I have of it:
(Click through for full resolution.)
If anyone has something better, please leave a comment or email me on email@example.com
September 30, 2015
Here’s the last post (at least for now) in the Fighting Apatosaur Art series — and we’re back to Brian Engh, who we started with.
Early in the process of putting together artwork to illustrate our apatosaur neck combat hypothesis, Brian tried out a whole bunch of outlandish concepts. Here are two that he showed us, but which were too speculative to push forward with. First, necks as big, floppy display structures:
As a piece of art, I really like this one: the boldness, the vivid contrasts, the alien quality of the animals. But as a palaeobiological hypothesis, it doesn’t really work: so much of the neck morphology in apatosaurs is to do with absorbing ventral forces that soft-tissue display structures down there don’t make a whole lot of sense.
Here’s the other one — which Brian titles “Apatosaur inflato-porcupine fish neck-bag”.
I particularly like the way the theropod being rolled around on the ground and repeatedly spiked. It’s no more than it deserves.
Does the idea of an inflatable neck make sense? I wouldn’t be at all surprised if there were sauropods that did something like this — plenty of extant animals inflate parts of their body for display purposes, after all — but I don’t think it would have been apatosaurs. Again, the characteristic features of the neck don’t seem well matched to this scenario.
Well, that’s all the apatosaur neck-combat art we have. If there’s to be a part 7 in this series, it will be made of artwork that you, dear readers, have contributed. Fire away!
September 28, 2015
If we accept that the distinctive ventral projections of the gigantic and ventrally displaced cervical ribs of apatosaurs were likely the base of some form of soft-tissue rugosity — such as keratinous horns like those of rhinos — then does it follow that those necks were used in combat as we suggested?
Maybe, maybe not. As scientists, we are always open to other hypotheses. We’re looking for the simplest, most parsimonious model — the one which best explains the facts.
That’s why we like Mark Witton’s “neck-velcro wall-climbing” hypothesis, as shown in this actual scientific life restoration.
As Mark explained to me, apatosaurs may have used their neck-hooks for more than passive clinging. They may also have been used for inching up the rock-face: first one side of the neck advancing and then the next, in the manner of the “pterygoid walking” that snakes use to progressively swallow large prey.
This is why it’s important to present early-stage work at conferences (and as preprints). Otherwise, you may never hear about important alternative hypotheses like this until after the paper is out and it’s too late to include them.
September 27, 2015
I mentioned last time that, as I sat next to Bob Nicholls in an SVPCA session, I started sketching an apatosaur combat in the hope that my horrible drawing would provoke Bob to do a good one. That worked admirably, which means there is no good reason for me to subject you to my own sketch.
So here it is.
I think the main lessons to draw from this piece are:
- I can’t draw heads.
- I can’t draw limbs.
- I can’t draw torsos.
- I may be just about capable of drawing tails.
During a break, I asked for Bob’s advice on how I can do better. I know I’ll never be an artist, but it’s fun to sketch (especially during mammal talks) and I’d like to improve a little. The main point Bob made was to think about where the light is coming from. Be consistent about that, and you get an immediate improvement in realism.
So here’s what I sketched the next day, with that in mind:
So what have we learned this time?
- I didn’t consciously do this, but I ended up with a composition kind of similar to what Bob came up with, but worse.
- In my desire to achieve the intertwined-necks pose, I made the necks too long and thin.
- I still can’t draw heads.
- Let’s just forget about the hindlimb of the one on the left.
- Uh, and let’s forget the torsos, too.
- But at least the light is coming from top right!
In short, as Stephen Sondheim put it, art isn’t easy. I wish I had more time to put into it.
The real moral of this story is: if I had a crack at drawing fighting apatosaurs, you definitely can. Let us know if you do — leave a comment. We’ll gather people’s contributions in a future post.
September 25, 2015
On the morning of Tuesday 1st December, on SVPCA day 1, I gave my talk about apatosaur neck combat. In one of the afternoon sessions, I sat next to Bob Nicholls, and found myself thinking how awesome it would be if he sketched some apato-combat.
But I didn’t want to come right out and say “Hey, Bob, how ’bout you spontaneously illustrate our palaeobiological hypothesis?” So instead I used a tactic that Fiona often uses when she wants me to do something: she starts to do it herself, badly, and waits for me to take over. (This is often how I find myself cooking in the evenings.) In the same spirit, sat next to Bob, I started a horrible sketch of wrestling apatosaurs. Sure enough, Bob, saw what I was doing, internally decided it ought to be done properly, and produced this:
What I love most about this (beside the casual way he knocked it out in fifteen minutes) is the sense of heft about the apatosaurs. These are big, solid animals. Someone’s gonna get hurt.
September 20, 2015
Last time, we looked at some of Brian Engh’s preliminary sketches of pieces to illustrate our fighting-apatosaur hypothesis. But there’s more: some way into the process, Brian also came up with this very rough sketch, illustrating a different style of combat:
All the pictures in the previous post show various forms of ventral-to-ventral combat, but we’ve also been thinking about possibilities, and an important one is ventral-to-dorsal.
That could work in at least two ways. We can imagine a wresting match, where each animal tries to get its neck above its opponent’s, and to force it to the ground. There is precedent for this in the behaviour of various extant animals. (Or perhaps I should call it postcedent, since apatosaurs came first.)
But other extant animals have a much more violent combat style, based on striking blows rather than exerting steady force. Notably, giraffes do this, using their long necks as levers to crash their uncharismatic, highly fused mammalians heads into each other.
Could apatosaurs have done this? Not exactly: their heads were far too small to be effective clubs, and far too fragile to survive being used in this way. But the necks themselves would have been formidable weapons: we’re confident that apatosaurs striking blows would have done so with their necks, bringing them powerfully downwards on their adversaries.
Brian liked this idea enough to work the rough sketch above up into a completed drawing, which we also plan to include in the paper (and which, by the way, I unreservedly love):
So what style of combat did apatosaurs use? Ventral-on-ventral shoving? Wrestling to the ground? Striking downwards blows with the neck?
My best guess (and it’s only a guess, necessarily) is that among the half-dozen or so recognised species of apatosaurine, all these styles were likely in use. And this may explain the variation in cervical morphology that we see between species (though of course ontogeny and sexual dimorphism may also be at work).
In short, I think all of these scenarios are credible — and therefore perfectly legitimate subjects for palaeo-art *hint hint*.