April 20, 2011
A few months ago, prosauropod supremo Adam Yates blogged about the Aardonyx cake that the BPI honours class baked in his honour. In the comments, I mentioned that my wife Fiona once made me a BMNH R5937:D9 cake (i.e. a cake in the form of the more posterior of the pair of nicely preserved dorsal vertebrae of The Archbishop, in right lateral view). At the time, I couldn’t find the photo that I knew had been taken, and Adam asked me to post it when it turned up.
And here, once more, is the real thing for comparison:
(Note that the topology of the lateral lamination is spot on, with a single infradiapophyseal lamina which forks into anterior and posterior branches only some way ventral to the diapophysis. That’s what you look for in a cake.)
Update (21 April)
Silly me, of course what I should have shown is the cake and the vertebra side by side. Here they are — together at last!
January 14, 2011
November 23, 2010
For anyone who doesn’t already know, Palaeontologia Electronica is an on-line, open-access palaeontology journal — the only one in the world (unless you count Acta Pal Pol, which is freely available online and also published on paper.) PE is sponsored by the Palaeontological Association, the Paleontological Society and the Society of Vertebrtate Paleontology, the big three professional associations, so you can see that it’s a serious journal, not just some glorified blog. Among much else, it has published important sauropod papers such as Gomani (2005), Schwarz et al. (2005) and Rose (2007). PE is A Good Thing.
The new issue 13(3) of PE came out yesterday and was introduced by a post on the newish PE blog. In response I was moved to post a comment on that blog post. But because the blog is pretty new, it doesn’t seem to have attracted many readers yet, at least judging by the low number of comments, so I realised that what I’d said needed saying in a more widely read venue. Hence this SV-POW! article.
I am absolutely in awe of the Boltovskoy et al. World Atlas — my hat is off to everyone who worked on it, and it’s great that a reference work this comprehensive is freely available to the world.
But PE‘s tiny images are becoming more and more of an embarrassment: something has got to be done about this. It’s true that the maps in the PDFs are pretty high resolution (I can’t see exactly how high because my usual extract-images-from-PDF program isn’t working on these files for some reason). But the versions of the figures on the web-site are really inadequate — see for example Figure 6, which is a feeble 711×358 pixels — 1/4 Mp.
Compare that with, for example, Figure 10 (dorsal vertebrae) of the paper published in PLoS ONE today on new American iguanodonts. That image is 2067×2776 pixels — 5+3/4 Mp, or 22 times the size of the PE image.
Folks, I love PE and I really want it to succeed. But the PLoS journals, among others have raised the game. Hosting large images is so cheap now that it’s hard even to measure the cost: there is no excuse for PE to continue providing its figures only in what amounts to a thumbnail. Why shouldn’t the original image files submitted by the author be made available?
For me, and I am sure many other people, this is a deal-breaker. I simply can’t and won’t send any descriptive papers to PE, because when I prepare a 4100×3966 pixel figure like the one above [cervical rib "X1" of the Archbishop -- click through that images for the full-size version], I can’t tolerate having it shrunk to 711×688 to fit PE’s 711-pixel width limit — a 33-fold drop from 16 Mp to 1/2 Mp.
Please, PE. Fix this. Surely it can’t be hard?
- Gomani, Elizabeth M. 2005. Sauropod dinosaurs from the Early Cretaceous of Malawi, Africa. Palaeontologia Electronica 8(1):27A (37 pp.)
- Rose, Peter J. 2007. A new titanosauriform sauropod (Dinosauria: Saurischia) from the Early Cretaceous of central Texas and its phylogenetic relationships. Palaeontologia Electronica 10(2):8A (65 pp.)
- Schwarz, Daniela, Christian Meyer, Eberhard Lehmann, Peter Vontobel, and Georg Bongartz. 2005. Neutron tomography of internal structures of vertebrate remains: a comparison with x-ray computed tomography. Palaeontologia Electronica 8(2):30A (11 pp.)
October 15, 2010
This post is nearly three weeks late — it’s based on a piece of artwork that appeared on 25 September, and which I wanted to write about immediately. But it got washed away in the flood of camel necks (which by the way is not over yet), and then in the festival of articular cartilage, then by the whole “Amphicoelias brontodiplodocus” thing and the subsequent discussion of amateurs in palaeo, and then by what was already an overdue announcement of my sauropod history paper and the attendant copyright nonsense. So it’s been a stupidly busy time here at SV-POW! Towers, but now the air has cleared a little, and it’s time to look at this beauty:
This would be a beautiful piece of art by any standards — the world can always use brachiosaur art! — but what makes this extra special for me is that it is the first ever life restoration of my very own brachiosaur, BHM R5937, the Tendaguru specimen known as The Archbishop. It’s by SV-POW! regular Nima, and I am absolutely delighted to see it. It’s very Greg Paul-like, and I mean that in the most positive sense. (I may not be a fan of Greg’s taxonomic vicissitudes, but his art is just beautiful.)
Over on his blog, Nima has described in detail how he created this piece, and shows four progressively refined versions (of which the one above is the last) — I urge you to check it out if you’re interested in art, brachiosaurs or both.
Nima’s blog-post also includes a brief history of the Archbishop, mostly taken from my 2005 SVPCA talk. It’s a good summary, but I do have a few comments to make. (I typed a lot of this in as a comment to the original post, but Blogger ate my comments as usual.)
- The specimen is not known as M23, and has never been — that is in fact the designation of the Tendaguru quarry from which is was excavated. Paul (1988) mistakenly conflated the quarry name with a specimen number, and referred to this specimen as BMNH M23, and Glut’s (1977) encyclopaedia perpetuated the error, but it’s always been R5937.
- “The giant Brachiosaurus finds of the Germans” are now, of course, Giraffatitan.
- “Controversy lingered” — well, no, not really. The problem was worse than that: no-one paid a blind bit of notice to the specimen before 2004.
- “It turns out the double spine claim was totally bogus and unscientific” — well, we don’t really know that yet. It’s certainly true that none of the prepared vertebrae (five cervicals, two complete dorsals and an additional dorsal spine) have bifid spines; but Migeod reported these from the anterior dorsals, and it’s not clear that we have those. A fair bit of material remains in jackets, and more has probably been lost or destroyed. So it is possible, if unlikely, that one day we’ll open one of those jackets and find good evidence for bifid spines.
- “Close-up of the Archbishop vertebrae (doesn’t look much like the mitre of an archbishop to me, but who knows” — well, the name The Archbishop is not based on any resemblance of the bones to a mitre. (Nor is it based on anything else. It’s completely arbitrary.)
Last 0f all, what about the actual picture? Well, the long, thin, snakelike neck is beautiful art, but I don’t think it’s great science. The height of the cervicals that we have for this animal show that the neck would have had to be quite a bit dorsoventrally taller than shown here. And because there were only 13 cervical vertebrae — 12 if you omit the atlas, which is really a whole nother kettle of badgers, a neck bent into a strongly sigmoid pose like this would exhibit noticable kinks at some of the intervertebral joints — as you can see in giraffes when they twist their necks.
That aside, though, this is great. Again, I am really delighted that it’s out there. Congratulations to Nima!
June 28, 2010
For reasons that seemed good to me at the time, I took my best shot at photographing the right cervical rib from cervical vertebra 3 of my ostrich, Veronica [see earlier Part A, Part B and Part C for context]. I thought you might like to see the result, so here it is:
For some reason, cervical ribs don’t seem to get a lot of love in the literature: the only paper I know that figures them in half-decent detail is Osborn and Mook’s classic (1921) monograph on Camarasaurus, and even there, the job is done in rather a half-hearted fashion. I’m planning to buck this trend by properly figuring the cervical ribs of the Archbishop when I finally get around to finishing that paper, and I included a sneak preview of the rib that I’ve arbitrarily designated X1 a while back. It’s instructive to compare that illustration with this one. In fact, here it is again:
Update (the next day)
It occurs to me that I should have composed the ostrich-cervical-rib illustration in the same orientation and order as the Archbishop one, for easier comparison. So that’s what I’ve done below. Since the Archbishop rib X1 is from the left side, I’ve also flipped the right-sided ostrich rib to match. Here it is:
February 12, 2010
Since I started taking photographs of sauropod vertebrae back in 2004, I’ve got much, much better at it, and for the last few months I’ve been meaning to write an article about what I’ve learned along the way. A few weeks ago, fellow SV-POW!er Ranger Matt Wedel posted an article on his 10 Minute Astronomy blog on how to photograph the moon through binoculars, and that served as a prod to get back into blogging gear in the post-Christmas season.
Before I launch in, let me be really clear that I am not a proper photographer — not at all. I don’t even know what an F-stop is or what Single Lens Reflex means. Probably I should invest some time into learning some of this, since specimen photographs are so important in the world of sauropod vertebrae. (After all, the specimens are more than a little cumbersome to loan, so photos often have to stand as proxies for the actual specimens.) Nevertheless, what I’ve learned in the last five or six years has got me to the point where I am producing much, much better specimen photographs than when I started, and I hope at least some of you can benefit from what I’ve learned.
First up, get a decent camera. However skilled you are, you can’t take better photos than the hardware allows. Although I am to blame for the composition above and for some of blurriness, the over-exposure, poor definition and artifacts are the fault of the camera. I was using a truly horrible camera back then — some super-cheap list-of-features-on-a-discount-website piece of kit.
The good news is that a “decent” camera doesn’t need to break the bank: for our purposes you don’t need to spend a fortune on professional-photographer standard equipment. I am looking on ebay right now, and it seems you can get my model of camera for £100 in the UK or $150 in the US (second-hand of course) which is a level of investment we really should be prepared to put into one of the most important aspects of descriptive work.
What constitutes a decent camera? Mostly, optics. These days, every camera has more than enough megapixels for most purposes, so you can just forget about that statistic altogether. It’s about the quality of the lens and the size of the CCD — those are the factors that determine how much information the camera can capture, and if it puts out more bits than that, then all it’s doing is wasting disk-space and bandwidth.
Can I justify the claim that all modern cameras have enough megapixels? I think so. Suppose you’re preparing a full-page plate for the Journal of Vertebrate Paleontology. In practice, plates are nearly always composites of several photos, but suppose you want a single shot filling the whole plate. The printable area of a JVP page is 182 x 233 mm, which is 7.2 x 9.2 inches. At 300 dpi, that’s 2161 x 2752 pixels, which is 5947072, or a slice under 6 megapixels. So 6 Mp is enough for a full-page plate. (For what it’s worth, my camera does 2272 x 1704 = 3.8 megapixels, and I have never found myself feeling a need for more resolution.)
For the same reason, you definitely want optical zoom rather than digital zoom, which really amounts to just blowing up the image.
Another big win: get a spare battery, so that one can be recharging while you’re using the other. If you don’t do that, your camera is out of commission half the time.
And get a big enough memory card. What’s “big enough”? For me, that means enough space to hold a whole day’s images so I can do a single dump onto the laptop in the evening, rather than having to keep stopping to transfer. I can take maybe a maximum of 300 photos a day. With 1 Mb images, that means I need a 300 Mb card, which is chickenfeed. You literally can’t buy cards that small any more, so this is not really a factor these days and I might just as well not have mentioned it. (The reason I did mention it is that my camera originally came with a 16 Mb card or something similarly stupid, which meant ten minutes or so of photography before downloading.)
Get the specimen in frame
Shoot from cardinal directions
Don’t put anything in front of the specimen
Use a plain background when possible.
But the good news is that all these problems can be ameliorated if you follow the last and most important rule in this section which is:
Take many shots and keep only the good ones
I remember reading once, long ago, that the single biggest factor in the difference of quality between a professional photographer’s work and an amateur’s is that the pro takes ten times as many shots and throws 90% of them away. In these days of digital cameras with huge memory cards, we can all make like professionals now. When Matt and I were at the Field Museum in Chicago, we took 168 photos of those Brachiosaurus dorsals alone. Of those, maybe a dozen or so are really worth keeping. But at least I have those dozen.
In general, I take every photograph twice. As I’ve got better at taking the photos, I am increasingly finding that both come out well and it’s a toss-up which to keep, but maybe one time in ten or twenty, one of them just doesn’t come out right — something is wrong with the focus, or the camera shakes, or something — and that’s when I’m glad I have the spare.
On the other hand, my camera’s built-in flash is pretty lame. Expensive flash units might do much better.
As with flash, it seems that the only thing to do is try photos with and without external lights, and with the lights in various different positions, and see what comes out best.
So what can you do? Well, there are several levels of compensation.
Simply being aware of remaining still
When I have to hold the camera in my hands and I know it’s going to be a long exposure I find myself going into a sort of zen state — I become aware of my heartbeat and try to time the shutter release so that the camera doesn’t get moved by my pulse. It’s error-prone, but at least being aware of it can help.
Brace against a door-frame or similar
The combination of tripod mounting and shutter delay means that you can get good exposure in almost any light.
… And finally …
From: Carol Brown<firstname.lastname@example.org>
We just posted an article, “100 Best (Free) Science Documentaries Online” (http://www.onlineuniversities.com/blog/2010/01/100-best-free-science-documentaries-online/). I thought I’d drop a quick line and let you know in case you thought it was something you’re audience would be interested in reading. Thanks
January 31, 2010
I hope you have a pair of 3D glasses. If you do, then check this baby out:
(This is of course the same vertebra that we last saw in a multi-view composite figure at the end of the Brachiosaurus coracoid post.)
I’ve started to get into the habit recently of photographing some specimens from two slightly different angles: I couldn’t tell you exactly how much rotation I use, but I would guess it’s something like three to five degrees. That’s because I’ve found that flipping back and forth between the two images can give a useful sense of depth. If you don’t believe me, here are two not-quite-identical photos of the Archbishop’s Cervical S: open each of them in a tab, then flick back and forth between them:
It had occurred to me a while back that, just for fun, it would be interesting to composite them into a red-cyan 3D image. But I was prodded into action by two things. First, the free Lego marketing magazine that my boys get sent every month arrived, and with it a freebie pair of cheap cardboard red-cyan glasses. And second, Matt published a steropair of moon images on his blog. Matt’s friend Jarrod is a professional digital effects artist — in fact he’s won Emmies for stuff like blowing up Los Angeles for 24 — and threw together an anaglyph from the moon pictures. I got instructions from Jarrod on how to do this, and was gratified how easy it was. Here you go:
- Open the two photos as two layers of a single image.
- Using the Colour Levels dialogue, turn the red channel of one of the photos all the way down to zero (so that it appears in shades of cyan)
- Using the same dialogue, turn both the blue and green channels of the other photo down to zero (so that it appears in shades of red)
- Change the Layer Mode of the top layer to Brighten Only
That’s it, you’re done! Save the resulting composite image as a JPEG and upload it to your sauropod-vertebra blog. Jarrod uses PhotoShop; I use the Gimp, which is a free more-or-less equivalent program — the same technique works fine with both.
If I was pleasantly surprised at how simple the technique is, I was astounded at the quality of the result. I’d expected all the colour of the image to be gone, and to see a vague monochrome haze. Instead, I saw rock-solid 3D in full colour — truly informative images that convey the morphology of complex bones far better than any published figure I’ve ever seen. Seriously, go get your red-cyan glasses, you won’t regret it.
Here is another anaglyph of the same vertebra, in posterior view close-up, showing in detail what looks suspiciously like a hyposphene below and between the postzygs. (If this is indeed a hypophene, then I believe it’s unique among sauropods.)
Journals have occasionally published stereopair images of palaeo specimens: small images a couple of inches wide, next to each other, which you can supposedly see as a single 3D image if you cross your eyes in just the right light provided the wind is from the southeast — personally, I have never been able to see these things, thought Matt can. But these big, full-colour 3d images are orders of magnitude more information.
I’ve never seen one in a journal, in part of course because colour printing is such an insanely expensive luxury. But as Matt says, we all live in the future now, and I hope that’s about to change. I will be sending the Archbishop description, when it’s done, to PLoS ONE, which because of its electronic-only format can include any number of full-colour figures at no cost. I plan to send a few anaglyphs among the more conventional figures. Fingers crossed that they make it into the published version — I guess if I get a traditionalist reviewer, he might think these are frivolous and demand that I remove them. But they are not frivolous: they may be the most informative figures I have ever prepared.
Finally, I leave you with our old friend the pig skull, from all the way back in Things To Make And Do part 1 — but this time in glorious 3D!