At the 2011 sauropod gigantism symposium in Bonn, John Hutchinson gave a talk on biomechanics of large animals. At the end he showed a short video of a rhino running full-tilt, tripping, and literally flipping end over end. After the wipeout, the rhino got up and trotted off, apparently unhurt. I don’t remember John’s exact words, but they were something like, “We have no idea how this happens – all our models suggest that rhino should be a pile of broken bones.”

His point was, there is a lot we don’t yet understand, and it pays to keep that in mind.

This morning Mike and I were discussing the Middlesborough meteorite, which fell to ground in front of some railway workers in 1881 and was reported be warm to the touch right after falling. Here’s a short, lightly-edited recap of our conversation.

Mike: If it had slowed to such a very mundane speed, due to atmospheric braking, how on earth was it only “new-milk warm” to the touch?

Me: You mean, since it was obviously melted to hell on its way in, how did it cool down so much? From what I’ve been able to find out so far, most small meteors that survive to hit the ground have finished aerobraking when they’re still about 50,000 feet up, and from there they experience a “dark fall” where they’re just a chunk of rock falling at terminal velocity. It’s pretty cold at 25,000 feet, much less 50,000 feet, so I assume a lot of the heat is pulled away by convection into cold air during the dark fall period. There are meteorites that have fallen onto lake or sea ice and not produced any apparent melting, so at least some of them do fall cold.

Mike: This makes sense. So we imagine that is was a lot hotter than that a short time before the impact, but that it cooled as it continued to fall.

This is an interesting example of how thoroughly physical intuition can mislead when you’re dealing with objects operating in unfamiliar realms: very big (e.g. the K/Pg impactor “splashing”), very small (e.g. insects “swimming” through air) or very fast (e.g. this meteorite’s temperature). Physics works over a huge range, and we only have developed intuition for a small sub-range.

Me: Your point about physics is well taken. The older I get, the more humility I have before nature, after seeing many, many things that I would have thought impossible.

The specific example I had in mind there was digging dinosaurs – if you’d asked me back when if any dinosaurs made burrows, I would have bet heavily against it. And yet, there they are.

Stay humble, folks. It’s weird out there.

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Back in 2009, I posted on a big cervical series discovered in Big Bend National Park. Then in 2013 I posted again about how I was going to the Perot Museum in Dallas to see that cervical series, which by then was fully prepped and on display but awaiting a full description. Ron Tykoski and Tony Fiorillo (2016) published that description a couple of years ago, and after almost five years it’s probably time I posted an update.

I did visit the Perot Museum in 2013 and Ron and Tony kindly let me hop the fence and get up close and personal with their baby. I got a lot of nice photos and measurements of the big specimen. It’s an impressive thing. Compared to the other big sauropod cervicals I’ve gotten to play with, these vertebrae aren’t all that long – the two longest centra are about 80cm, compared to ~120cm for Sauroposeidon, Puertasaurus, and Patagotitan, and 137cm for Supersaurus (more details here) – but they are massive. According to the table of measurements (yay!) in Tykoski and Fiorillo (2016), which accord well with the measurements I took when I was there, the last vert is 117.5cm tall from the bottom of the cervical rib to the top of the neural spine, 98.4cm wide across the diapophyses, and has a cotyle measuring 29cm tall by 42cm wide. Here it is with me for scale:

I guarantee you, standing next to that thing and imagining it being inside the neck of a living animal is a breathtaking experience.

I failed in my mission in one way. In a comment on my 2013 post, I said, “I’ll try to get some good lateral views of the mount with as little perspective as possible.” But it can’t be done – the geometry of the room and the size of the skeleton don’t allow it, as Ron noted in the very next comment. There is one place in the exhibit hall where you can get the whole skeleton into the frame, and that’s a sort of right anterolateral oblique view. Here’s my best attempt:

So, this is an awesome specimen and you should go see it. As you can see from the photos, the vertebrae are right on the other side of the signage, with no glass between you and them, so you can see a lot. The rest of the exhibits are top notch as well. Definitely worth a visit if you find yourself within striking distance of Dallas.

Reference

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.

We’ve not done many picture-of-the-week posts here recently. Let’s change that! Here’s a lovely little specimen that we saw in BYU on the 2016 Sauropocalypse trip.

Wedel and Taylor (2013), Figure 7. BYU 12613, a posterior cervical of Diplodocus, in dorsal (top), left lateral (left), and posterior (right) views. It compares most favourably with C14 of D. carnegii CM 84/94 (Hatcher, 1901: plate 3) despite being only 42% as large, with a centrum length of 270 mm compared to 642 mm for C14 of D. carnegii.

(At least, this is catalogued as Diplodocus. Jaime Headden suggested, and Emanuel Tschopp corroborated, the idea that it’s more likely Kaatedocus.)

References

Wedel, Mathew J., and Michael P. Taylor. 2013a. Neural spine bifurcation in sauropod dinosaurs of the Morrison Formation: ontogenetic and phylogenetic implications. PalArch’s Journal of Vertebrate Palaeontology 10(1):1-34.

Welcome to 2017! Let’s start the year with a cautionary tale. I’ll leap straight to the moral, then give an example: it’s very easy to reach the wrong conclusion about fossils from photos. That’s because no single photo can give an accurate impression of distortion. For that, you need at least a much bigger selection of photos; or better still, a 3d model; or of course best of all, the fossil itself.

Here’s the motivating example:

unnamed

Cervical vertebrae 8-16 of Barosaurus lentus AMNH 6341; and BYU 9024 “Supersaurus” cervical ?9. All in left lateral view.

A correspondent — I will not divulge his or her name unless the person in question chooses to reveal it — had looked over the slides for our 2016 SVPCA talk on new Barosaurus specimens, which claims that Jensen’s Dry Mesa “Supersaurus” cervical BYU 9024 actually belongs to Barosaurus.

Matt and I felt, based largely on the degree of neural spine bifurcation, that the BYU vertebra compares most similarly to C9 of the AMNH specimen — the middle one in the top row of the composite illustration above. But my correspondent put together the composite, and wrote [lightly edited for clarity]:

I’ve already compared BYU 9024 with the AMNH cervicals, I attach a photo, because for me it is also very similar to C14: the centrum is much more similar to C14 than C9, I think. What do you think about this?

Like I said: you always need to be careful about interpreting any one view of a fossil. In this case, BYU 9024 is misleading in lateral view because the CPOLs are folded upwards and inwards, and the ventrolateral flanges are (to a lesser extent) folded downwards and inwards — making the posterior part of the centrum look much taller (and rather narrower) than it really is.

This is hard to see in photos, because the fossil is so smashed up and the matrix is so visually similar to the bone, but take a look at the posterior view (with anterior to the right of the photo):

img_3516

Here are the key parts, annotated, as best I can make out. (And bear in mind that even I am not sure, after having spent a whole day with the fossil, and with literally hundreds of photos to consult.)

img_3516-annotated

As you can see, the centrum accounts for only a small proportion of the apparent height of the posterior end of the vertebra — and even that is probably exaggerated, as the eccentricity of the condyle indicates that crushing has increased its height at the expense of its width.

Put it all together, and Jensen’s much-derided sculpture of what the vertebra should have looked like is actually pretty good:

img_3399

The upshot of this anecdote is an obvious one, but it bears repeating: you simply cannot do a meaningful description of a fossil without seeing it yourself — or at the very least a high-quality 3d model. Photos just won’t cut it.

Back at the start of September, I noted that Tschopp and Mateus (2016) had published a petition to the ICZN, asking them to establish Diplodocus carnegii as the type specimen of the genus Diplodocusa role that I argued it already fulfils in practice.

I wrote a formal comment in support of the petition, which I submitted on 7 September; and the next day I had word from the secretary of the ICZN that it had been received and would be published in the next issue of the BZN — the Bulletin of Zoological Nomenclature.

Since then I have had emails from a couple of different people asking me for the formal citation details of my comment, and I have made three or four separate attempts to discover whether it’s appeared in BZN yet. And I have been completely unable to find out.

First stop is the ICZN web-site’s case-finder, available in the sidebar at pages such as Cases and List of Available Names. But that doesn’t find Case 3700 (the Diplodocus case). I don’t just mean it doesn’t find my comment; it doesn’t find the case at all.

By poking around the site at random, I found this page, which has a tree-structured list of cases in its sidebar. Towards the bottom is a link to Case 3700 — hurrah! — but that link just says “BZN view could not find any content :(”

All right, then, let’s go to the ICZN’s site’s page about the Bulletin. As the page itself proudly proclaims in the sidebar, “The Bulletin of Zoological Nomenclature (ISSN:0007-5167) is the official periodical of the International Commission on Zoological Nomenclature”. And yet the page content just says:

Bulletin

Either no literature content has been added to this site, or it has not yet been indexed. Indexing can take up to one hour, so please check back later.

So I tried a more general search for the BZN elsewhere on the Web.

All in all, there seems to be literally no meaningful Web presence of the Bulletin of Zoological Nomenclature — which is the journal of record for, well, Zoological Nomenclature. If, like me, you want to discover the status of cases … well, you just can’t.

Oh, at no-one at the ICZN Twitter account is responding to my tweets. But then the most recent tweet from that account is from 15 May 2014, so it’s been dormant for more than two and a half years.

So my question is: *knock knock* is anyone home?

Here’s why this matters. It’s well established that Zoological Taxonomy is important (e.g. Vink et al. 2012) and that as a discipline it’s under threat. Now, the ICZN is the only game in town when it comes to authoritative taxonomy. It is the undisputed guardian of the zoological taxonomic record, and it’s had to weather threats to its own existence before a recent injection of funding. So it’s crucial that, as the standard bearer of its field, the ICZN does a solid, competent, professional, reliable job.

That has to start with making the journal of record available — or at least, if the Commission really really doesn’t want to go open access, making its table of contents available so people can see what’s been decided. If that’s not happening, then whatever decisions the Commission makes are the sound of a tree falling in a deserted forest.

We need the ICZN to up its game.

References

So I came across this tweet from Laurent Gatto, who’s head of the Computational Proteomics Unit at the University of Cambridge, UK:

My immediate reaction was not to retweet. Why? Because I am not comfortable recommending rejection (or acceptance!) of something I’ve not seen. I said so, and Laurent explained the real issue:

So I have two simple questions:

First, How can this massive spending on public money possibly be confidential? What justification can there possibly be for that? And second, how can there be meaningful discussion of the offer on the table if no-one knows what it is?

And then I remembered the classic explanation of confidentiality clauses from Elsevier’s David Tempest: “we have this level of confidentiality […] Otherwise everybody would drive down, drive down, drive drive drive”.

So my first reaction was to say that if anyone comes across a leaked copy of the draft agreement, let me know and I will link to it from this post. But I am also open to hear from anyone who thinks there is a legitimate reason, that I’ve not thought of, to enforce confidentiality. So if you have a reason, please mention it in the comments. If not, but you know where there is a leaked copy, email me privately on dino@miketaylororg.uk.

One more SVP book signing

October 29, 2016

imageWe keep selling out of books, which is a nice problem to have, but still a problem for people who want books. So we’re getting a final shipment this morning, and Mark Hallett and I will be at the JHUP booth signing books, starting at 12:15 and going until we run out of either customers or books.

Many, many thanks to everyone who has gotten a book or just stopped by to chat. We’re humbled by the great response we’ve gotten.

Parting question: someone on Facebook asked if we could sign and mail bookplates for folks who can’t get to our signings. I’m cool with that, just curious about how much interest there might be. Let me know in the comments.