Hallett and Wedel 2016 with friends

I came home from SVPCA to find a heavy box waiting for me. It had my author’s copies of the book. I figured maybe they had gone out in advance of wide release, but nope, the book is shipping right now. This is welcome but unexpected. We only got the final files in a little over three months ago. I have no idea what alchemy the folks at Johns Hopkins University Press worked, to get the book out so fast, but I’m grateful.

We’ll have a book signing at SVP, at one in the LA area with both of us, and probably some local ones in Oregon and SoCal with just one author. I’ll announce those when we get them set up.

I have about a zillion people I need to thank, and I’ll probably do a FAQ about the book soon, but for now: it’s out.  JHUP page. Amazon page.

Hallett and Wedel sauropod book on Amazon

Publisher’s description here, Amazon page here.

I’ll have a lot more to say about this in the future, but the short version is that I met Mark Hallett at one of my first SVP meetings in 1997 or 1998. Way back then, he shared with me his vision of doing a big, lavishly illustrated book on sauropods. Fast forward to 2011, when Mark contacted me and asked if I’d be willing to serve as a reviewer for the sauropod book that he was writing. I told him that because I was on the tenure track I had to be pretty jealous with my time, so there was a limit to how much time I could invest as a reviewer. However, if he would take me on as junior author, the book would become part of my professional output and there would be no limit to how much time I could put into it (words that would turn out to be prophetic!). Mark agreed, and after 5 years of hard work, mostly on Mark’s part, here we are. The wheels are turning and with any luck the book will be out before the end of the year.

Mark and I owe a big debt of gratitude to the people who did agree to review the book: Kristi Curry Rogers, Carole Gee, John Hutchinson, and Paul Upchurch. We couldn’t have asked for a better team.

Stay tuned!

Dodo monograph cover - Claessens et al 2016

Here’s an awesome thing that just landed in my mailbox: the new monograph on the Thirioux dodos by Leon Claessens and his collaborators. They’ve done a better job describing what’s cool about these specimens than I could, so for the rest of this post I’m just borrowing their text from the Aves3D site, where you can view 3D models of whole dodo skeletons and many individual elements (not to mention zillions of elements from lesser, non-dodo birds):

The dodo (Raphus cucullatus) skeleton on exhibit at the Durban Natural Science Museum is one of two unique skeletons discovered and assembled more than a century ago by the amateur naturalist Etienne Thirioux. Thirioux’s two dodos are unique, not just because they are the most complete skeletons in existence, but also because they are the only two skeletons comprised of the bones of either a single individual bird (the Port Louis dodo), or the bones of (only) a few different birds (the Durban dodo). In contrast, all other known dodo skeletons are incomplete and are typically put together from separate fossil bones uncovered at a marsh called the Mare aux Songes.

Port Louis dodo skull - Claessens et al 2016 figure 6

Port Louis dodo skull – Claessens et al 2016 figure 6

The Thirioux specimens contribute greatly to our understanding of the anatomy of the extinct dodo and are the subject of a new, major monographic treatise:

Anatomy of the dodo (Raphus cucullatus L., 1758): An Osteological Study of the Thirioux specimens.
Leon P. A. M. Claessens, Hanneke J. M. Meijer, Julian P. Hume, and Kenneth F. Rijsdijk (Editors).
Society of Vertebrate Paleontology Memoir 15, Journal of Vertebrate Paleontology Vol. 35, Supplement to No. 6.

We are pleased to make the Thirioux dodo skeletons available to the public for viewing on Aves 3D and Sketchfab. Please enjoy these wonderful scans of the skeleton of a fascinating bird, and check back on the site frequently, as we continue to upload more new dodo bone scans each week.

Leon Claessens
for the Dodo Research Programme and the Aves 3D team

Congratulations, Leon and team, on a landmark publication. And thanks for all the free dodo visualizations!

For previous dödö-related musings, please see this pöst.

Port Louis dodo skeleton - Claessens et al 2016 plate 1

Port Louis dodo skeleton – Claessens et al 2016 plate 1

Building on the pioneering work of Karbek (2002), Darren Naish (circa 2004) conceived a theory of sauropod locomotion that has not been as widely accepted as he might have hoped. Sadly, other projects captured Naish’s attention, and his interest in writing up his theory waned. All that now remains of this sadly unpublished work is this speculative life restoration:


We can only lament the loss of this unique perspective to science.


  • Karbek., T. R. 2002. The case for Stegosaurus as an agile, cursorial biped. Journal of Vertebrate Paleontology 22(Suppl. to 3):73A.

Building on the pioneering work of Myhrvold and Currie (1997), Darren Naish (circa 2003) conceived a theory of sauropod defence that has not been as widely accepted as he might have hoped. Sadly, other projects captured Naish’s attention, and his interest in writing up his theory waned. All that now remains of this sadly unpublished work is this speculative life restoration:



  • Myhrvold, Nathan P. and Philip J. Currie. 1997. Supersonic sauropods? Tail dynamics in the diplodocids. Paleobiology 23:393-409.

I’d hoped that we’d see a flood of BRONTOSMASH-themed artwork, but that’s not quite happened. We’ve seen a trickle, though, and that’s still exciting. Here are the ones I know about. If anyone knows of more, please let me know and I will update this post.

First, in a comment on the post with my own awful attempts, Darius posted this sketch of a BROTOSMASH-themed intimidation display:


And in close-up:


Very elegant, and it’s nice to see an extension of our original hypothesis into other behaviours.

The next thing I saw was Mark Witton’s beautiful piece, described on his own site (in a post which coined the term BRONTOSMASH):

BRONTOSMASH Witton low res

And in close-up:

BRONTOSMASH Witton low res-closeup

I love the sense of bulk here — something of the elephant-seal extant analogue comes through — and the subdued colour scheme. Also, the Knight-style inclusion in the background of the individual in the swamp. (No, sauropods were not swamp-bound; but no doubt, like elephants, they spent at least some time in water.)

And finally (for now, at least) we have Matthew Inabinett’s piece, simply titled BRONTOSMASH:


I love the use of traditional materials here — yes, it still happens! — and I like the addition of the dorsal midline spike row to give us a full on TOBLERONE OF DOOM. (Also: the heads just look right. I wish I could do that. Maybe one day.)

Update (Monday 26 October)

Here is Oliver Demuth’s sketch, as pointed out by him in a comment.


Thanks, Oliver! Nice to see the ventral-on-dorsal combat style getting some love.

So that’s where we are, folks. Did I miss any? Is anyone working on new pieces on this theme? Post ’em in the comments!


I imagine that by now, everyone who reads this blog is familiar with Mark Witton’s painting of a giant azhdarchid pterosaur alongside a big giraffe. Here it is, for those who haven’t seen it:

Arambourgiania vs giraffe vs the Disacknowledgement redux Witton ver 2 low res

(This is the fifth and most recent version that Mark has created, taken from 9 things you may not know about giant azhdarchid pterosaurs.)

It’s one of those images that really kicks you in the brain the first time you see it. The idea that an animal the size of a giraffe could fly under its own power seems ludicrous — yet that’s what the evidence tells us.

But wait — what do we mean by “an animal the size of a giraffe”? Yes, the pterosaur in this image is the same height as the giraffe, but how does its weight compare?

Mark says “The giraffe is a big bull Masai individual, standing a healthy 5.6 m tall, close to the maximum known Masai giraffe height.” He doesn’t give a mass, but Wikipedia, citing Owen-Smith (1988), says “Fully grown giraffes stand 5–6 m (16–20 ft) tall, with males taller than females. The average weight is 1,192 kg (2,628 lb) for an adult male and 828 kg (1,825 lb) for an adult female with maximum weights of 1,930 kg (4,250 lb) and 1,180 kg (2,600 lb) having been recorded for males and females, respectively.” So it seems reasonable to use a mass intermediate between those of an average and maximum-sized male, (1192+1930)/2 = 1561 kg.

So much for the giraffe. What does the azhdarchid weigh? The literature is studded with figures that vary wildly, from the 544 kg that Henderson (2010) found for Quetzalcoatlus, right down to the widely cited 70 kg that Chatterjee and Templin (2004) found for the same individual — and even the astonishing 50 kg that seems to be favoured by Unwin (2005:192). In the middle is the 259 kg of Witton (2008).

It occurred to me that I could visualise these mass estimates by shrinking the giraffe in Mark’s image down to the various proposed masses, and seeing how credible it looks to imagine these reduced-sized giraffes weighting the same as the azhdarchid. The maths is simple. For each proposed azhdarchid mass, we figure out what it is as a proportion of the giraffe’s 1561 kg; then the cube root of that mass proportion gives us the linear proportion.

  • 544 kg = 0.389 giraffe masses = 0.704 giraffe lengths
  • 259 kg = 0.166 giraffe masses = 0.549 giraffe lengths
  • 70 kg =0.0448 giraffe masses = 0.355 giraffe lengths

Let’s see how that looks.

Arambourgiania vs giraffe vs the Disacknowledgement redux Witton ver 2 low res

On the left, we have Mark’s artwork, with the giraffe massing 1561 kg. On the right, we have three smaller (isometrically scaled) giraffes of masses corresponding to giant azhdarchid mass estimates in the literature. If Don Henderson (2010) is right, then the pterosaur weighs the same as the 544 kg giraffe, which to me looks pretty feasible if it’s very pneumatic. If Witton (2008) is right, then it weighs the same as the 259 kg giraffe, which I find hard to swallow. And if Chatterjee and Templin (2004) are right, then the giant pterosaur weighs the same as the teeny tiny 70 kg giraffe, which I find frankly ludicrous. (For that matter, 70 kg is in the same size-class as Georgia, the human scale-bar: the idea that she and the pterosaur weigh the same is just silly.)

What is the value of such eyeball comparisons? I’m not sure, beyond a basic reality check. Running this exercise has certainly made me sceptical about even the 250 kg mass range which now seems to be fairly widely accepted among pterosaur workers. Remember, if that mass is correct then the pterosaur and the 259 kg giraffe in the picture above weight the same. Can you buy that?

Or can we find extant analogues? Are there birds and mammals with the same mass that are in the same size relation as these images show?


  • Chatterjee, Sankar, and R. J. Templin. 2004. Posture, locomotion, and paleoecology of pterosaurs. Geological Society of America, Special Paper 376. 68 pages.
  • Henderson, Donald M. 2010. Pterosaur body mass estimates from three-dimensional mathematical slicing. Journal of Vertebrate Paleontology 30(3):768-785.
  • Witton, Mark P. 2008. A new approach to determining pterosaur body mass and its implications for pterosaur flight. Zitteliana 28:143-159.