Brontomerus cartoon - John Trotter - paintmonkeystudios-dot-com

One of our army of field correspondents, Seth Segal, sent us a scan of this cartoon from the spring 2011 issue (#97) of Prehistoric Times (yes, we’re a bit late to the party on this one). Shifty little weasels that we are, we were entertained by it, so we tracked down John Trotter at Paintmonkey Studios. He kindly sent the nice version you see above, and gave us permission to post.

I really like the idea of undescribed dinosaurs just going about their business, and then being surprised by having new names sprung on them. I can well imagine some of them being disappointed, too.

Argentina…saurus. Lizard. From. Argentina. Seriously? You know, there’s a million dinosaurs from Argentina. Why do I get stuck with the generic name that is actually generic? Nothing about how big I am? Really? I mean, I weigh, like, two Supersauruses. What’s the Latin for double-Supersaurus-rex? And here I am with Antarctosaurus–that poser’s got a whole continent in his name, and he’s not even from there! And what about that so-called “earthquake lizard”? I heard they found him wandering around all delusionsal, claiming to be 150 feet long and the biggest thing ever, and the cops had to remind him he’s just an old-ass Diplodocus. Play some more Brain Age, grandpa! Forget it. I’m gonna go hunt up Brazilsaurus and Uruguaysaurus and get a football game together… What do you mean, they haven’t been named yet? Aw, man!”


Pre-emptive note to the etymology mafia: yes, I know that Antarctosaurus means “southern lizard”, not “lizard from Antarctica”. But in this joke, Argentinosaurus is not so well-informed.

This imaginary interlude was brought to you by Becky Crew’s habit of putting words in animals’ mouths, and by Mike’s proposed moratorium on “place-saurus” names, and by the number 11.

I’m delighted to have the opportunity to exhibit some more Brontomerus artwork.  Once more, as with National Geographic and indeed the original life restoration in the paper, Matt and I had the opportunity to work with the artist, feeding back on an initial draft, to help get the final version as accurate as possible.

Andy Boyles is the Science Editor for Highlights for Children magazine.  They’re planning a feature on Brontomerus, and commissioned a cartoon-style life restoration from artist Robert Squier.  Here’s his first finished draft:

When Robert sent this to the magazine, he included some helpful notes:

Attached is my sketch of Brontomerus. You’ll see some spines on my sketch; I understand that some similar sauropods had them. And it looks like paleontologists haven’t found any bones that would rule out these details.

But I’ll be happy to lose them if you’d like.

Also, I based my Brontomerus skull on the skeleton (fig. 1) in the PDF you provided. I aimed to make the head like that of the Camarasaurus, since the text says the two dinos were similar.

The head in the illustration (fig. 12 ) looks like it’s based on a different dino – Apatosaurus. I’m sure your experts will set me straight.

Also added a Utahraptor.

I look forward to your feedback!

That’s the point where Andy emailed Matt and me asking if we had any feedback.  It happened that I got to that message before Matt did, and this is what I sent back:

Hi, Andy, great to hear from you. It’s always a pleasure when our work is explained to the public, especially for kids. And I am especially delighted by the artwork. I don’t know if this statement really means anything, but it feels to me that it’s somehow captured the *spirit* of Brontomerus.

I do have some criticisms, though! I am attaching an annotated copy of the artwork, which should help to clarify these comments. All my modifications are in red, so they should be easy to pick out.

And here is the modified version that I attached:

My message explained further:

1. Maybe most important — our speculation about Brontomerus‘s kick behaviour was to do with it kicking forward like a soccer player, not backwards like an ostrich. So to be in danger zone, the Utahraptor should be in front of Brontomerus‘s poised leg, not behind. The raptor should also be a bit bigger in comparison.

2. You’ve really captured the bulk of muscle on the front of the thigh well, but the back should probably be bulging slightly.

3. There is a distinct bulge on the side of the torso where the profile of the shoulder blade is visible. This is good, but it should be further up and further back.

4. The head is a little too big. In the annotated version, I’ve scaled it to 90% of its previous size, which looks roughly right to me.

5. The classic mistake that everyone makes when illustrating sauropods is to give them a full complement of hand-claws. (It’s the first thing that smart-alec palaeontologists look for when they see a piece of sauropod art!) In reality, only the thumb would have had a (small) visible claw, and the other digits would have been fully enclosed in a sort of fleshy mitten. There’s a decent illustration showing the right forefoot of a sauropod, from the left (part 4a) and from in front (part 4b). It’s well worth reading the very good article [from Tetrapod Zoology] that this was used in:

I also replied to the artist’s comments:

The spines are perfectly possible and rather handsome. I particularly like that the adult has them and the baby does not: these would likely have been sexual display structures, so it’s appropriate that they would develop only with increasing maturity.

The head is excellent. You are quite right to base it on Camarasaurus rather than the very different skull of Apatosaurus. If I were to quibble, there is no reason to think that the regions between the bones would be very hollow, especially the one behind the eye.

Less than three weeks later, back came the modified version of the art — and I was delighted to see that every single issued I’d raised had been dealt with.  Here is the final version of the pencil sketch:

You’ll notice that the raptor has moved into the danger-zone, the rear of the thigh is more muscular, the scapular bulge has moved up and back, the head is slightly smaller and doesn’t have a visible indentation for the temporal fenestra, and the forfeet have lost all but their thumb claws.

Finally, here is the coloured version as it will appear in the Magazine in April 2012: I like the bold splashes of orange.

I’m really pleased to have permission from Highlights to exhibit both the pencil sketch and the final piece here, at high resolution.  Please note that both versions are copyright Highlights.  Many thanks to both Robert and Andy for being so responsive, helpful, and generous.

Looking again at this, I am impressed by two things.  The first is just how far palaeoart has leapt ahead in recent decades, when even an illustration for a kids’ magazine is as anatomically careful as this — note details like the pronounced ventral bulge for the distal part of the pubis, and the distinctively camarasaurian head.  We’ve come a long way from the old balloon-model sauropods.  The second is related: it’s just great that the magazine took the trouble to contact scientists over this piece, and that artist was so obliging in responding to the issues we highlighted.  It’s worth opening all four versions of the artwork in browser tabs, and switching between them to see how the piece changed from start to finish.

All of this brings me to a point that I’ve wanted to make before, but which seems particularly relevant here.  It’s very common for scientists in general, and palaeontologists in particular, to complain about their work being misrepresented in the media.  I’m sure it happens — we all remember Matt’s awful experience with Clash of the Dinosaurs — but I think it’s much more the exception than the rule.  In my own limited experience, I’ve found print journalists, artists and radio and TV people pretty much uniformly great to work with: genuinely interested, keen to get the details right, and willing to work with rather than against the scientist.  I’m sure it helps that I take the time to prepare materials for journalists ahead of time rather than just expecting them to make do with the paper and the press-release [Xenoposeidon, neck posture, Brontomerus], but that’s not rocket science.  Anyone who cares about getting their research reported right can do that.  And media people want to do their job right.

Update (4th January 2013)

Very belatedly, I am posting the final final version of the artwork, which Andy sent me back on 26th March 2012! Following a comment by Mickey Mortimer on this very post, Andy got into a discussion with Mickey about feathers. As a result he had David Justice, Highlights‘ in-house art-repair wizard, patch up Utahraptor long after the art was due and they had no time to send it back to the illustrator. Here is the result:


(Note that the colours have also been tweaked.)


With our baby’s appearance in National Geographic this week, she’s now been in four mainstream magazines:

That’s National Geographic at top left, Macleans  next to it; The Scientist at bottom left, and National Geographic Kids next to that.  (The articles in the first three of these are available online here, here and here, but I can’t find anything on the NG Kids web-site.)

There is a point to this post, beyond gloating celebrating Brontomerus: it’s that diligent preparation improves a study’s chance of getting good coverage.  A few people have asked us to write a bit about what we did, so at the risk of sounding self-congratulatory, here it is.

Most of Brontomerus‘s visibility is due to the hard work of the UCL Publicity team, and especially the excellent and widely-reproduced video that they made in the Grant Museum.  But we made it easy for UCL to take an interest by preparing a bunch of materials ahead of time, before they even knew that there was a paper coming out.  We called it the Brontomerus press pack, and made sure it contained everything anyone could need for writing and illustrating stories about our animal:

In short, we tried to give journalists, and radio and TV researchers, everything they needed to put together a story aimed at their own audience.  More than that — we tried to make it easy for them.  They have plenty going on, after all: Brontomerus came out on the day that the Libyan protests really took off, so it’s not as though news editors were short of material to fill their slots.  I suspect that if we’d not got all the ducks in such a neat row, Brontomerus would have disappeared from the news schedule in double-quick time.

Another important thing you can do to make news editors’ jobs easier: make sure that the images you provide are in high resolution, so they don’t pixellate when they’re blown up to fill a screen; and be explicit about image/video credit, copyright and permissions.  Let them know what they can use and under what conditions.  If you make them hunt for that information, or even chase you for it, they’ll probably lose interest and do a different piece instead.  And we really wanted the artist who’d done the Brontomerus work to be credited: Paco Gasco did a fantastic job, and deserved to be known for it.

Equally important, by getting as much material as possible ready before even contacting the university publicity people, we made their job easier.  Once they were on board, we were able to extend the page with extras like an official press release and the video, but the framework was all in place ahead of time.

In short, there is a whole load that you can do to prepare a study for media coverage.  Not much of it is rocket-science.  It’s basically just about getting the work done.  And it is work, plenty of it.

Still.  It’s worth it.

And another thing …

You should all get across to Heinrich Mallison’s new blog and check it out.  Lots of excellent palaeo-photography, even if today’s post is about a stinkin’ mammal.

Addendum (from Matt)

First, some credit where it’s due. We didn’t figure all of this out on our own. For Brontomerus in particular, we took a lot of cues from  the fact sheet that Irmis et al. put together for their 2007 “rise of dinosaurs” paper that made the cover of Science.

Second, we did figure some of it out on our own, but not all at once. If you look at Mike’s unofficial online press packs for Xenoposeidon (2007), our neck posture paper (2009), and Brontomerus (2011), you’ll see that each one is better than the one before.

Finally, you may be saying to yourself, “Okay, I understand that I’m supposed to make things easy for journalists and have a bunch of stuff queued up for them. But where do I put it?”

Well, online, obviously. If you don’t already have a blog, WordPress and Blogger and probably a zillion other services give them out for free, and you can make an ad hoc, one-shot blog for every press-release-worthy paper, as Mark Witton and Darren did for their azhdarchid paleobiology paper in PLoS ONE.

But let me wax preachy for a minute. If you’re a young researcher and you’re trying to make an impact, why aren’t you blogging? It’s not an intolerable commitment. Sure, regular posting brings more readers, but irregular posting brings more readers than not having a blog at all.

We started SV-POW! as a joke, and continued it during the actually-posting-weekly-about-sauropod-vertebrae phase (which lasted for 2.5 years) because it was fun and challenging, and maintain it now because it’s fun, we enjoy the wacky discussions that get going from time to time in the comments, and, frankly, we’re addicted to having a soapbox where we can say pretty much whatever we want. We didn’t explicitly plan it as a way to funnel readers to our scientific work, but that has been one of its great exaptive benefits. I’d be shocked if the same isn’t true for other researchers who blog.

So, moral of the story: if you’re a researcher and you’re not blogging, you’re missing out. Your work is reaching fewer people than it might. Come out and play. Join the conversation. Interact. Your future self will thank you.

Brontomerus by Mauricio Antόn, copyright National Geographic

The October 2011 issue of National Geographic is out, and in the ‘Now’ section near the front there is a one-page feature on Brontomerus (in the US version anyway).  The whole thing is can be viewed online here.  It’s page 30 in the hardcopy, but NG seems pretty cavalier about printing page numbers.

The art is by Mauricio Antόn and we’re super happy with it; as before we had the opportunity to go back and forth a lot and arrive at a finished piece that shows essentially everything we wanted. The author of the piece, Catherine Zuckerman, was also very patient in distilling down the reams of information Mike and I sent her about the story. Many thanks to both Mauricio and Catherine for their interest and hard work!

It’s been a couple of months since Brontomerus came out, but new coverage continues to trickle in. For anyone who’s still following, I thought I’d draw attention to a few that I particularly like.

A favourite is One Hip Dino in The Scientist.  It’s told largely from Matt’s perspective, and includes quotes by Mike D’Emic, Susie Maidment and Ray Wilhite.  (Although D’Emic’s statement that “The ilium projects forward by 55 percent, while in other species it’s 52 percent” could do with some substantiation — I think we’ve shown pretty convincingly how different the ilium is from anything else out there.)

The most recent of the new articles is The biggest, baddest dinos still rule, in Macleans, which describes itself as “Canada’s only national weekly current affairs magazine”.  I guess that makes it Canada’s Time or Newsweek, and it has 2.4 million readers.  Despite the rather unpromising title, the article is good, and touches on some of the potential downsides of palaeo publicity.

But one of the best things about publicising Brontomerus has been hearing about how it’s been used in education.  (As one example, it was the lever that got me an opportunity to give a talk about palaeontology and evolution at my eldest son’s school a few weeks ago.)  One article describing Brontomerus‘s involvement in engaging kids’ interest is Dinosaur teaching topics – how to name a dinosaur at Everything Dinosaur.  The author tells me “we chose Brontomerus as the focus for our teaching session and I introduced concepts such as ontogeny and used the children’s knowledge of how farmyard animals grow and change, relating this to the fossil evidence of the adult and juvenile of the Brontomerus genus.”

Another benefit of letting the world know about Brontomerus was that it opened the door to my writing an article for the Guardian‘s science blog: How I got to know thunder thighs, the dinosaur with a fearsome kick.  They chose the title, sadly: I’d suggested something more like “How we know what we know”, and that is indeed that main topic of the article.  It was a rare opportunity to talk in a mainstream media outlet about how we actually do palaeontology, and the varying levels of certainty in which we hold different conclusions.

I hesitate to mention it, but the New York Times did a piece on, well, mostly me: Dinosaur-hunting hobbyist makes fresh tracks for paleontology.  I’m mostly really happy with it, except that an unfortunate bit of abridgement gives the impression that I described Jack McIntosh as “a minor paleontologist”.  Let the record show, that is not what I said: it’s actually how I described myself.

Finally, I’d like to draw attention to a very cheerful interview that Australian science blogger Bec Crew did for ABC Radio’s Triple J channel, in a program called The Doctor on 8th March.  Bec is best known for her truly unique blog Save your breath for running ponies, (I can’t help inserting the missing comma in the title), and my only regret regarding Brontomerus is that it’s never been given the SYBFRP treatment.

That’s all for now.

Atacamatitan chilensis gen. et sp. nov., caudal centrum SGO.PV.961c in ventral (A) and ventrolateral views (B); caudal vertebrae SGO-PV-961h in lateral (C) and dorsal (D) views. Scale bars: 50 mm. (Kellner et al. 2011:fig. 2)

Let’s look a bit more closely at the holotype element of Brontomerus mcintoshi, which as we all remember is the juvenile left ilium OMNH 66430.  Much of what we’ve said about Brontomerus is based on the shape of that ilium, so it’s important to get right.  Several commentators have expressed skepticism about how we reconstructed, so I thought it would be worth taking the time to explain why we put it together we way we did.

First, let’s orient ourselves.  Here is the torso from the skeletal inventory that was Figure 1 of the paper (Taylor et al. 2011, natch).  In this version, I’ve highlighted the ilium in red.  We’re looking at the left side of the animal, so the main part of the bone is further forward than the hip socket, towards the animal’s head.

As you’ll see from the area that we left shaded grey, a chunk is missing from the middle of the ilium, where it was damaged in the field.  As the figure of the ilium in the paper shows clearly, what we actually saw in the OMNH collection was three chunks of bone: a big one consisting of the acetacular margin, pubic and ischiadic peduncles and most of the preacetabular blade; and two smaller fragments, each contributing part of the dorsal or posterior margin.

We spent a while in the OMNH collection playing with the three chunks to see how they best fit together.  In doing this with the actual bones, we were able to take account of their curvature in the third dimension, which our figure don’t show — although a dorsal-view photo gives some idea.

Anyway, we this is what we came up with:

(Sorry if that image is getting a bit overfamiliar, but it’s worth seeing again in the context of this post.)

You’ll remember from the Clearing the Air post that Jim Kirkland, who excavated the ilium, felt that we’d got the two smaller fragments in the wrong places relative to the main chunk, and also that a fourth fragment which we’d missed also belongs to the ilium.  He kindly sent a photo of how he’d reconstructed the ilium, and I used the arrangement of pieces in the photo as the basis for a “what if” alternative reconstruction.

So far, this is old news.  But what was maybe not quite clear in the post is how very similar the two reconstructions really are.  Let’s fix that: here they are side by side, with ours on the left and Jim’s on the right:

It seems pretty clear that even if Jim’s arrangement is correct (which Rich Cifelli  disputes), that doesn’t affect the reconstruction in any significant way.

But the real question is why we put in that dotted line — and why we put it where we did.  How do we know there wasn’t a normal-sized postacetabular lobe sticking out behind?  This is what Jamie Headden wanted to know in an email to me shortly after the paper come out.  With his kind permission, I reproduce the illustration that he prepared, showing (A) the reconstruction from the paper, and (B) how it might have been different:

The reason we rejected a reconstruction like the one in Jaime’s part B is explained (too) briefly in the paper (pp. 80-81):

The postacetabular lobe is reduced almost to the point of absence […]  The ischiadic peduncle is reduced to a very low ventral projection from almost the most posterior point of the ilium. The near absence of the ischiadic peduncle cannot be attributed to damage as the iliac articular surface is preserved. Immediately posterodorsal to this surface is a subtle notch between the peduncle and the very reduced postacetabular lobe. This notch and the areas either side of it are composed of finished bone, demonstrating that the great reduction of the postacetabular lobe, too, is a genuine osteological feature and not due to damage.

To my lasting annoyance, I didn’t take any posterior-view photos of the ilium back in 2007, so I can’t show you this finished bone as well as I’d like — this was back before I’d learned all my lessons on how to photograph bones.  But here is a close-up of the posterovental extremity of the ilium, again from Fig. 2, showing the notch: I have left the postacetacular lobe in colour, and desaturated the ischiadic peduncle — the notch is between them.

This next photograph of the ilium, again in lateral view, is lit rather differently from the one we used in the figure, so that you can see a distinct shadow lying along the valley between the ischiadic peduncle and what there is of the postacetabular blade.

Here’s one that shows the main chunk of the ilium in anteromedial view: from here, you can more easily see the the distinction between the ischial peduncle (which projects towards the camera) and the preserved, ventralmost, part of postacetacular blade, which is further back.

And one in posteroventral view: this is similar to our Fig. 2b, but from a slightly more posterior (and medial) perspective, so that you can more easily see the mediolaterally compressed posterior lobe sticking out behind the broader ischial peduncle at top right:

What all these photos unfortunately do not show is the finished nature of the bone on the posterior margin of the postacetacular blade — on that, you just have to take our word.

But the point is this: we have the whole of the ischiadic peduncle and the ventralmost part of the postacetacular blade — we know that the posteriormost preserved part of the main chunk of ilium is not part of the peduncle (so that the postacetabular blade is missing), but that this really is the blade itself.  And because the bone is not broken, we know that the trajectory of the posterior margin of the postacetabular blade was directed dorsally from the posterior point of the peduncle.

I hope that’s clear.  What I really should have done, of course, was take my own good advice and get photos from every angle — and, ideally, pairs that would have allowed me to show the relevant features as anaglyphs.

Anyway, all this shows that the shape of the ilium really was pretty much as we reconstructed it — and, most, importantly, that the bizarre proportions we reported in Table 4 are correct: preacetabular blade, measured parallel to the longest axis of the ilium equal to 55% of total length; postacetabular blade equal to 0%.

Exactly how strange is this almost non-existent postacetabular blade?  In the paper we described it as “remarkable”, but it’s not completely unprecedented.  Lehman and Coulson (2002:fig. 8) showed the left ilia of six somphospondylians:

As you can see, the Euhelopus zdanskyi and Saltasaurus loricatus ilia both lack postacetabular blades (although Powell 1992:fig. 18 suggests that the posterior portion of the Saltasaurus ilium may be broken).  Where Brontomerus is unique is in the combination of this postacetabular reduction with the enormous preacetabular blade.

All clear?  Good.

“But wait!”, I hear you cry.  “That ilium is juvenile!  How do you know that its strange shape is not a juvenile feature?”

Stay tuned!  All will be revealed.


Sorry for the very short post. We have some longer stuff planned, but we’ve been too busy to kick it out this week, and I wanted to leave you with something cool to ponder over the weekend. Here’s the ilium of Giraffatitan overlaid on that of Brontomerus, scaled to the same acetabulum diameter (Giraffatitan is HMN J1, left ilium, modified from Janensch 1961: pl. E, fig. 2; Brontomerus is of course OMNH 66430 from Taylor et al. 2011:fig. 2).

And here’s the same thing comparing Rapetosaurus and Brontomerus (Rapetosaurus is holotype FMNH PR 2209, left ilium, modified from Curry Rogers 2009: fig. 39B). This one was tricky to scale because the ilial margin of the acetabulum is so different in the two taxa.

Here is the same trick performed with the ilium of the canonical pretty basal neosauropod Camarasaurus — specifically, Camarasaurus supremus AMNH 5761 Il. 1, left ilium, modified from Osborn and Mook (1921: fig. 87).  In this case, the proportions are so very different that it’s hard to make a meaningful superimposition: we tried to scale to equal acetabulum size, but probably that of the Camarasaurus was proportionally larger than in the other taxa illustrated in this post.  Still, here it is:

Finally, in response to Paul Barrett’s comment on a subsequent article, here is a superimposition of the ilium of Alamosaurus on that of Brontomerus:

(Sorry about the poor quality of this one, but the only figure I could find of a complete Alamosaurus ilium was the line-drawing in Lehman and Coulson (2002:fig. 8) — none of the standard descriptive works seem to illustrate a complete or near-complete ilium.)

We had a figure like these in an early draft of the paper, but we ditched it because we felt that doing a broader comparative figure would be more valuable. But I like the kick in the brainpan that these overlays provide.



Many people in the paleontological community have probably seen the comments about our work on Brontomerus by Jim Kirkland. Most of these comments have been posted on Facebook or sent around by email. We have held off until now in responding to them because we wanted to have everything–both the criticisms and our responses–publicly available to everyone, not in the walled garden of Facebook. Jim has now stated on Facebook that we have permission to post his messages and respond to them, and his longest critique has been posted as a comment on the initial Brontomerus post.

All three of us–Mike, Matt, and Rich, the authors of the new paper describing Brontomerus–have known Jim for some time. He and Rich collaborated in the Cedar Mountain Formation for most of the 1990s, and basically split the catch, with Jim getting most of the dinosaurs and Rich getting the mammals. Matt has known Jim since the late 1990s, and has had many productive conversations with him about sauropods and faunal change in the Early Cretaceous of North America. Mike’s interactions with Jim have been more limited, mainly because they live on different continents, but he has spoken to Jim at meetings and they have exchanged occasional correspondence–always friendly–for years.

Not only has Jim been a friend of ours for some time, he also assisted with the Brontomerus project. Jim first alerted Rich to the existence of the quarry in 1994. Following Rich’s visit to the quarry in September of that year, Jim went out with Scott Madsen and Randy Nydam to collect the fossils of what would become Brontomerus in 1995, and the fossils were prepared under his guidance at Dinamation before being transported to the Oklahoma Museum of Natural History for curation. Jim was also helpful in providing information about the quarry and allowing us to cite personal communications from him in the paper.

We’ve all had long and productive working relationships with Jim for years, and we’d like to see those relationships continue. However, some of his comments are not only factually incorrect but also call our veracity and scientific judgment into question. We feel that the record should publicly be set straight.

In the rest of the post, we have the full text of Jim’s long SV-POW! comment and some of his comments from Facebook,  followed by a breakdown of his specific claims and our responses to them.

Jim’s self-described rant

On February 23, Jim sent around an email with the subject “Brontomerus pdf and rant”. ReBecca recently posted a slightly longer version here on Jim’s behalf.

While, it is possible, that Brontomerus is a new species based solely on the juvenile ilium, there is no way based on the minimal contextual information known of this site, that one can say that all the sauropod material we collected at Hotel Mesa pertains to the same species.

When, I was first taken to this site in 1994, it had been opened by guys hoping to develop a commercial Morrison dinosaur quarry. The Bureau of Land Management (BLM) clearly did not OK this! Another party, who told me he had only advised them to get a permit, subsequently took me out to the site.

Examining this site, it was obviously in the Cedar Mt. Fm. [LINK] and of great interest to me, but politics being what they were, I could not get a BLM permit in Utah and as I had recognized a fair number of teeth and claws (theropods and crocs) in the site, I thought perhaps it might be a potential microvertebrate site, so I asked Rich Cifelli at the OMNH if he might be interested in the site. Rich put me on his Utah BLM permit and sent out Randy Nydam and I corralled Scott Madsen (then at Dinosaur National Monument (DNM) and we went out to evaluate the site for microvertebrates and salvage the exposed bones. This took us about 1.5 days (camped for two nights). Unfortunately, the matrix would not break down and thus the site could not be screenwashed for microvertebrates, so Rich lost interest in the site. We prepared all the bones in our (Dinamation Intl. Soc.) lab in Fruita, Colorado before sending them on to the OMNH with his crew when they returned to Oklahoma from working their Utah sites at the end of the following summer.

After, I became Utah’s State Paleontologist in 1999, I expressed interest in reopening the Hotel Mesa Quarry, as this was the only Albian age site in all of eastern Utah, but BLM policy was that all specimens from a given site needed to be reposited at the same repository. Therefore, since Utah paid my salary, it was impossible to justify excavating and preparing a collection of vertebrate materials and sending them to Oklahoma.

A few years ago, Mike Taylor informed me that he and Matt Wedel felt that there was a new sauropod taxon in the collections from Hotel Mesa. I was excited to learn this, as I figured they would seek to open the site and collect more specimens and data concerning this important locality.

I was deeply saddened to learn they had described the new sauropod taxa with no regard to establishing a base of contextual data to support its hypodym.

First there is no evidence to suggest that all the sauropod bones in the site pertain to the same taxon. The Holotype ilium (cute as a bugs ear, I must say, particularly before the shim went through the middle of it, when we flipped the scapula jacket), comes from a much smaller animal that the rest of the reported “hypodym”.

The nearly equivalent and geographically much closer Price River 2 Quarry preserves more than one sauropod taxon among the many hundreds of sauropod bones collected there. Staff at CEUs Prehistoric Museum pointed out that they had long cervicals similar to Sauropossiden and short stouter cervicals. Their new director Ken Carpenter sent me this picture [LINK] showing two morphs of ilia (at top of figure), one with a short prepubic portion and a stout pubic peduncle and on with a long prepubis and slender pubic peduncle. Thus, the Upper Albian part of Cedar Mt preserves a wealth of sauropods and this taxon promises to add to the general confusion regarding North America’s Early Cretaceous sauropods.

Also in terms of stratigraphy (and these guys are not completely at fault here, but if asked I would have told them), the Ruby Ranch Member is Albian in age from all our dating. Abydosaurus mcintoshi from DNM is not from the younger Mussentichit Mbr. but the upper Albian (Chure et al.’s 2010, date of ~104 Ma says that) and as stated in … our abstract coming out at GSA this spring and to be submitted as a manuscript long before that, An unconformity (sequence boundary) separates the basal Cenomanian (98-96 Ma) Mussentuchit from the Albian strata below it. Two date, there are no over lapping parts between Brontomerus mcintoshi and Abydosaurus mcintoshi and these two sites may nearly be equivalent.

The much older upper Barremian to basal Aptian Dalton Wells Quarry low in the Cedar Mt has at least 3 sauropod taxa among the numerous individuals in Brigham Young University’s collection. Remember the Cedar Mountain represents about as much time as the entire Upper Cretaceous.

Basically, the statement that the juvenile holotype belongs to the same taxon as the handful of adult material in the site is a stretch without some supporting taphonomic documentation (more excavation, as the site keeps going. However, the statement is a falsifiable hypothesis so is a scientific statement that needs testing.

Now that we are beginning to excavate our own sauropods, which thank god are at the base of the Cedar Mt. Fm., I’m actually beginning to care about the general taxonomic mess that Albian sauropods are in with the number of taxa described without overlapping parts.

Another observation that I accidentally made was that the reconstruction of the ilium in the paper, differs from that we made in preparing the specimen fresh from the field. These two reconstructions are shown in at the bottom of the picture. We figure this reconstruction from 1995 in Kirkland and Madsen, 2007, Fig. 13E, p. 15). On line at: [LINK]

I’m certainly curious what happened between Rich’s OMNH crew’s picking the specimens up and Mike and Matt’s beginning their research on it. Regardless of whatever happened, it is clear the proportions on the Holotype ilium need to be reappraised.

PLEASE, someone open up this quarry and generate some real information (it is an 8hr drive from Salt Lake City, so I do not have the funds to undertake this). The site is in the Dolores Triangle so the Hotel Mesa Site can only be approached from Colorado, so the Museum of Western Colorado is by far the closest institution to it.

AND; finally, the site is actually in the Burro Canyon Formation not the Cedar Mountain Formation as the name changes as you cross the Colorado River going east. So the stratigraphic level would be, for the sake of accuracy by best referred to as high in the Ruby Ranch Member of the Burro Canyon Formation. This is how it is show on the recently published 1X100,000 geological map of the area. Geological jargon that is useless to argue with unless you are going to publish the justification of changing the convention.

Oh and there are many dozens of sauropods waiting to be excavated in the Ceadar Mountain Formation during the “Age of Ankylosaurs.”

Done spouting off for the minute.

Jim Kirkland

Jim’s Facebook comments

Besides the email/SV-POW! comment, Jim has posted some serious criticisms of the paper on Facebook. These started back in January, when the accepted manuscript of the as-yet-unpublished paper was inadvertently posted on the Acta site. Jim kindly took them down following our request that he do so. However, the deleted criticisms had already been seen by hundreds of people  (Jim has 898 Facebook friends) and received many comments, so we feel that it is appropriate to publicly respond to them.

[January 28] Since Abydosaurus mcintoshi and Brontomerus mcintoshi are essentially from the same stratigraphic horizon ~ 150 kilometers apart and have no overlapping parts yet. It is an interesting synonymy since the species name would not change. We have all these sauropod skeletons in the Cedar Mountain, lets not describe scrap.

[January 28] I have wanted to see the Hotel Mesa site (turned over to OMNH) excavated for more than a decade. To describe a dinosaur from scrap salvaged from site and to leave rest rotting in the ground is irresponsible!

[January 28] Jim Kirkland: WTF I oversaw the collection of it all, as salvage over a couple of daysl None of these guys have been to site (more there). No way, you can say anything, but the type illium goes to this species.
Darren Naish: Are you sure that none of the guys have been to the site? Err…Rich Cifelli?
Jim Kirkland: I guarantee it, they would never find it.

[February 23] I just realized that they reconstructed the ilium of Brontomeris wrong! See my Hotel Mesa album. It is not thunder thighs, but at most quivering thighs! I would say it throws a big hook into the entire thing.

[February 23] There is no evidence that anything was stolen from the site or smashed for that matter. They simply uncovered it and inquired about a commercial permit.[speaking here of the alleged vandalism of the site by commercial collectors]

Specific claims, and our responses

We’re rather baffled by some of Jim’s statements. Rather than go through the email and Facebook comments line by line or in chronological order, we’ve distilled his criticisms into a number of specific claims, which appear here with our responses.

Claim 1: None of the authors ever visited the quarry.

Source: Facebook, “None of these guys have been to site…I guarantee it, they would never find it.”

Response: This not just incorrect, but insulting. From the paper (Taylor et al. 2011: 76):

One of us (RLC), who had already been working in Lower Cretaceous rocks of the region, was notified about the site through the courtesy of James I. Kirkland, and was guided to it by Bill Hawes of Grand Junction, Colorado, in September 1994. Additional collecting at the site for OMNH was conducted by Randall L. Nydam and James I. Kirkland in March 1995.

In an email to Matt and Mike with permission to cite, Rich wrote:

I took the information directly from my field notes and I remember the place pretty well. Of course I was there!

Claim 2: We erred in describing the site as being part of the Cedar Mountain Formation rather than the Burro Canyon Formation.

Source: SV-POW! comment, “the site is actually in the Burro Canyon Formation not the Cedar Mountain Formation as the name changes as you cross the Colorado River going east. So basically the proper description of the site would say, it is in the upper part of the Ruby Ranch Mbr. of the Burro Canyon Formation.”

Response: We acknowledge this in the paper, and clearly state that our discussion of the site as part of the CMF is one of convenience (Taylor et al. 2011: 76):

Stratigraphically, OMNH V857 lies in a sequence of Lower Cretaceous rocks interposed between the Morrison Formation (Kimmeridgian) below and the Dakota Formation (Cenomanian) above. Westward, these rocks are recognized as the Cedar Mountain Formation; eastward, the Burro Canyon Formation. The arbitrary dividing line between these entities is generally placed at the Colorado River (Stokes 1952; Tschudy et al. 1984) which technically places OMNH V857 within the Burro Canyon Formation. However, we will refer to the locality as belonging to the more widely recognized Cedar Mountain Formation, as it is in this formation that comparable specimens are known, and the stratigraphy and sedimentology do not change across the arbitrary border.

It is also worth noting that in his long comment, Jim himself discusses the quarry as part of the Cedar Mountain Formation, presumably out of convenience: “Examining this site, it was obviously in the Cedar Mt. Fm.” (from the third paragraph of his SV-POW! comment).

Claim 3: The quarry probably has more than one sauropod taxon, because other CMF quarries sometimes have more than one sauropod taxon. (conflicts with Claim 8)

Source: SV-POW! comment, “First there is no evidence to suggest that all the sauropod bones in the site pertain to the same taxon. The Holotype ilium (cute as a bugs ear, I must say, particularly before the shim went through the middle of it, when we flipped the scapula jacket), comes from a much smaller animal that the rest of the reported “hypodym”.

“The nearly equivalent and geographically much closer Price River 2 Quarry preserves more than one sauropod taxon among the many hundreds of sauropod bones collected there.”

Response: This is a possibility we discuss extensively in the paper (Taylor et al 2011: 79), but so far there is no evidence to support it. All of the material is consistent with a single taxon, most likely a basal somphospondyl, but conservatively a camarasauromorph.  (We plan to talk much more in a subsequent article about this tentative assignment of all the material to a single taxon.)

There is a more general point to be made here. Any time someone erects a new taxon, the idea that the taxon is actually distinct from other, previously named, taxa is a hypothesis subject to further testing. Anytime someone refers material to a taxon, that is likewise a hypothesis. If we pretended to be any more certain about the referral than we actually are, we’d be lying. But we’d be equally in error if we didn’t point out that the null hypothesis is that all of the material belongs to one taxon. If contrary evidence comes to light, we’ll take it into account and move on–that’s how science works.

If someone find a complete titanosaur skeleton with an ilium like the holotype of Brontomerus, and someone else turns up a complete rebbachisaur with a scapula like the one currently referred to Brontomerus, great!  Name the rebbachisaur (a North American rebbachisaur would rock!), remove the scapula from the Brontomerus Referred Material list, and move on.  As we made clear in the paper, Brontomerus is based on, and diagnosed by, the holotype ilium alone.

Claim 4: There is no evidence that anything was stolen or destroyed from the site.

Source: Facebook, “There is no evidence that anything was stolen from the site or smashed for that matter. They simply uncovered it and inquired about a commercial permit.” Also repeated second-hand as a comment on Dinosaur Tracking, here.

Response: In an email with permission to cite, Rich wrote:

Yes, of course it had been excavated: we have proof in my notes and in Randy Nydam’s field notes. The comments about bone strewn around and being used to hold pieces of blue tarp are, unfortunately, accurate.

What’s more puzzling is that all three of us have received emails from Jim going back to 2007 that clearly state that the quarry was vandalized.  For example (and note the explicit permission to cite):

Message-Id: <>
Date: Mon, 17 Mar 2008 10:22:12 -0600
From: James Kirkland
To: Mike Taylor
Subject: Re: Another Hotel Mesa pers. comm.

[…].  The small ilium was under the scapula (completely hidden and the shim went through the middle of it, but we were able to prepare it with it’s entire margin reconstructed.  (collected by Jim Kirkland, Scott Madsen, & Randy Nydam from site that had been uncovered previously by vandals).  […]

Site this.

Claim 5: The quarry is full of more and better sauropod material.

Source: Facebook, “To describe a dinosaur from scrap salvaged from site and to leave rest rotting in the ground is irresponsible!”

Response: Any material exposed near the surface at Hotel Mesa in 1994 and 1995 is long gone by now, crumbled by 16 years of freeze/thaw cycles and erosion by wind and water. There may be more material deeper down, a possibility that we have always acknowledged, but since no one has ever seen that material, it is impossible to say if it’s better than what we have, or if it even exists at all. This is actually not unusual for dinosaurs; many taxa are known from quarries that are not worked to exhaustion and later produce more material. One of our express aims in writing this paper was to to provide the impetus for further excavation in the quarry, and there was no prospect of that happening before we started working on it.

Claim 6: It was irresponsible of us to name a new dinosaur based on such incomplete material.

Source: Facebook, “We have all these sauropod skeletons in the Cedar Mountain, lets not describe scrap.”

Response: Although incomplete, the material still bears numerous autapomorphies that clearly indicate that it is a new taxon based on currently available data (see point 3, above, on hypotheses).

Since the material in the quarry was not articulated, we would have had to choose an isolated element as the holotype even if we had more material (and the ilium would still have been the obvious choice because it is so unusual). This is absolutely critical: in a bonebed of disarticulated elements, it wouldn’t matter if we had just the ilium or 5000 bones, we’d still have to pick one element as the holotype and refer everything else to it. Anyone describing a new taxon from disarticulated elements in a bonebed faces the same decision: for example, Kirkland et al. (2005), in their description of the basal therizinosaur Falcarius, nominated a partial braincase as the holotype and referred all the other material.

Claim 7: We erred in attributing Abydosaurus to the Mussentuchit member of the Cedar Mountain Formation.

Source: SV-POW! comment, “Abydosaurus mcintoshi from DNM is not from the younger Mussentichit Mbr. but the upper Albian (Chure et al.’s 2010, date of ~104 Ma says that) and as stated in … our abstract coming out at GSA this spring and to be submitted as a manuscript long before that,”

Facebook, “Abydosaurus mcintoshi and Brontomerus mcintoshi are essentially from the same stratigraphic horizon” [Brontomerus is from the Ruby Ranch member]

Response: The only published peer-reviewed work on the Abydosaurus quarry (Chure et al. 2010) places it in the Mussentuchit member. Jim’s abstract was not available to us when we were writing the paper, and if we had the option to choose between the conclusions of a peer-reviewed paper and those of an unpublished abstract, we’d still have followed the paper. Abydosaurus could actually be from the Ruby Ranch member, but we will wait for the published evidence, and to see what Chure et al. have to say in response.

Claim 8: Because Abydosaurus is from the Ruby Ranch member, Brontomerus might simply be Abydosaurus. (conflicts with Claim 3)

Source: Facebook, “Abydosaurus mcintoshi and Brontomerus mcintoshi are essentially from the same stratigraphic horizon ~ 150 kilometers apart and have no overlapping parts yet. It is an interesting synonymy”

Response: The hypothesis that Abydosaurus is from the Ruby Ranch member is far from convincingly demonstrated (see above). The Ruby Ranch member has at least two sauropods other than Brontomerus, and the Yellow Cat member has between three and five, so the idea that there is only one sauropod genus in each member of the CMF, and that therefore Brontomerus must be synonymous with Abydosaurus, is insupportable. Potential synonymies among Early Cretaceous North American sauropods are acknowledged and discussed extensively in the paper (Taylor et al. 2011: 87-88, 91-92).

Also, we note that back in January, Jim was concerned that Brontomerus was synonymous with Abydosaurus (not enough new sauropods in the quarry), and now in his comment he is concerned that there might be more than one taxon in the quarry (too many new sauropods). Which is it, and what aspects of our discussion of these problems in the paper does he find incomplete?

Claim 9: Jim’s photo of the reconstructed ilium shows that our reconstruction is wrong and that our conclusions are therefore suspect.

Source: Facebook, “I just realized that they reconstructed the ilium of Brontomeris [sic] wrong! See my Hotel Mesa album. It is not thunder thighs, but at most quivering thighs! I would say it throws a big hook into the entire thing.”

Response: Yesterday (February 23) we received an email from Jim, with this photo:

The body of the email:

I just realized that the ilium is reconstructed wrong in the paper. Here is how we reconstructed it straight in from the field..
Sorry guys.

Jim’s reconstruction includes a small piece of bone in the dorsal margin of the iliac crest that is not in our reconstruction. Here’s a comparison Mike put together to show which bits are which:

Jim’s reconstruction is different from ours, but that does not automatically make it correct. This just in by email (with permission to cite) from Brontomerus co-author Rich Cifelli, who is curator at the Oklahoma Museum of Natural History where the fossils are curated:

From: Rich Cifelli
To: Mathew Wedel, Mike Taylor
Date: 25 February 2011 00:45
Subject: restorations of Kirkland vs. Taylor et al.


I have re-examined the various pieces of the holotype ilium (OMNH 66430). Our restoration stands as the only one that is really plausible, and is the best match considering the thickness, curvature, preservation, and surface texture of the three main pieces (large section including acetabulum, peduncles, and pre-acetabular blade; followed by thin strip of margin; followed posteroinferiorly by “Oklahoma-shaped” piece with margin). The other piece shown by Kirkland (roughly rhomboidal in outline) was omitted by us because it does not include any of the bone margins (contra Jim’s restoration) or contacts with other pieces: it fit somewhere in the large space posterior to the pre-acetabular blade and dorsal to the acetabulum.

Kirkland’s restoration cannot be “straight from the field” because it is obviously incorrect in placement, orientation, and side shown for the rhomboidal piece. As said, this fragment does not contain any of the bone margin: all of the edges, including that which he depicts as lying along the posterior-posterodorsal margin of the ilium, are jagged and broken. Color, surface texture, and an important morphological feature also show that he depicts this piece upside down. That feature is a ridge which separated attachment places for two sacral ribs, shown by Kirkland to be lateral (facing outward) but which of course should be medial.

But, all right, suppose Jim had been right about how the pieces should fit together: here’s a new recon by Mike that follows the photo Jim sent.  Note that all the pieces fit comfortably within the very same dotted reconstruction line as in Fig. 2 of the paper.

It is also important to realize that the ilium is oriented differently in the two photos. The photo on the left in the comparison image, from Taylor et al. (2011: fig. 2), is a straight lateral view, looking straight down the laterally-oriented axis of the acetabulum. The preacetabular blade of the ilium angles out anterolaterally, as shown in our Figure 2B. In Jim’s photo, on the right of the comparison image, the preacetabular blade is lying flat on a table, which puts the acetabulum at an angle to the camera; the photo is effectively in posterolateral view rather than orthogonal, and this is the source of all the significant differences between the two photos. Take Jim’s reconstruction, mentally rotate it laterally through 20-30 degrees to look straight down the acetabulum, and his post-acetabular expansion would fit comfortably into the dotted line we drew, as Mike’s new recon shows.

The diagnostic features (autapomorphies) of the ilium are (Taylor et al. 2011: 78):

  1. Preacetabular lobe 55% of total ilium length, longer than in any other sauropod;
  2. Preacetabular lobe directed anterolaterally at 30 degrees relative to the sagittal plane, but straight in dorsal view and vertically oriented;
  3. Postacetabular lobe reduced to near absence;
  4. Ischiadic peduncle reduced to very low bulge;
  5. Ilium proportionally taller than in any other sauropod—height is 52% of total length, compared with a maximum of 45% in other sauropods.

If Jim’s reconstruction were right, it would only change the margin of the iliac crest, so it couldn’t affect characters 1, 2, or 4. His reconstruction still shows the postacetabular lobe reduced to near-absence (3), which still leaves the ilium proportionally taller than in any other sauropod (5).  In short, the version he favors doesn’t affect the proportions or autapomorphies one whit.

The alternative reconstruction is valuable because it points out the existence of a missing piece of the wing of the ilium. However, not only is it wrong in the position of that piece, even if it was right it wouldn’t affect our morphological, taxonomic, or functional interpretations of Brontomerus at all.


Thanks for slogging through this long, probably not-terribly-interesting post. We’ll soon return to normal service, with more information on Brontomerus — and that awesome life restoration.


Matt or I will probably post properly later today, but I just wanted to post a quick note to ask whether anyone has any printed (as opposed to online) newspaper copy on Brontomerus?  Although TV, radio and online coverage has been pretty good, I had the impression that it hardly made a dent in print at all, and in fact the only article I’ve seen is this tiny one in the Evening Standard (London’s free evening newspaper):

Evening Standard, Wednesday 23rd February 2011, page 2: London Experts discover Thunder Thighs

If anyone has printed copy other than this, I’d really appreciate it if they could send it to me.  (If it even exists.)  If that’s you, please leave a comment and post your clipping to:

Mike Taylor
Oakleigh Farm House
Crooked End
Gloucestershire  GL17 9XF


This is the clearing-house page for all things Brontomerus. Thanks for your interest!

The paper

Freely available to the world, thanks to the wonder of Open Access publishing, something we strongly believe in.

For some of our rants and ramblings about OA publication and related matters, please go here.

Unofficial supplementary information

You can get this from Mike’s web-site. It includes the Nexus file used for the phylogenetic analysis, full-resolution versions of the figures from the paper, and additional specimen photographs.

Press pack

Loads of hopefully useful stuff, including a fact sheet, another version of Francisco Gasco’s beautiful life restoration, and some videos, are available here. UCL’s YouTube channel also has the video.

Two additional videos posted by the Oklahoma Museum of Natural History:

SV-POW! posts

The list to date:

Media coverage

Not an exhaustive list, just some that we’ve noted so far.



News on the Web

Other blogs