What is the origin of these Barosaurus photos?
February 27, 2022
For this forthcoming Barosaurus paper, we would like to include an establishing photo of the AMNH Barosaurus mount. There are two strong candidate photos which we’ve used before in an SVPCA talk, but since this is a formal publication we need to be more careful about copyright. Here are the photos, which are the property of their respective rightsholders:
This one is hard to find at all, at least using Google’s reverse image search. Whereas this one …
… is sprinkled all over the Internet, but (in all the cases I’ve seen so far) without attribution.
Does anyone have the necessary skills to track down who the rightsholder is for either of these? Thank you!
The mounted skeleton of Patagotitan at the AMNH
April 3, 2018
Click to titanosaurize. Trust me.
I was in Philadelphia a couple of weeks ago to work with Liguo Li, of Yongjinglong fame, and I took a day to run up to New York for a quick day’s work at the American Museum of Natural History. It was my first time visiting since the cast skeleton of Patagotitan went up, so it was my first chance to see that beast in the flesh (so to speak). The pano up top is mine, but the other two photos here are by Liguo. I’m writing with my thoughts on the mount.
Pros:
- It’s big.
- You can walk all the way around it, with no glass in the way.
- It’s very convincing. The casting job on the real elements is superb, with all of the cracks and so on faithfully recorded. And the vertebrae they had to sculpt look pretty good.
- The spotlights aimed at the neck cast these immense shadows of the cervical vertebrae on the far wall, which is cool (see below).
- Now the AMNH has mounted skeletons of Brontosaurus (or some apatosaurine at any rate), Barosaurus, Kaatedocus (masquerading as a juvenile Barosaurus in the rotunda), and Patagotitan – that’s pretty not bad. I’m hard pressed to think of another museum in the Western Hemisphere with so many mounted sauropod skeletons. Carnegie, maybe? Someone help me out, here.
Cons:
- In striking contrast to the well-lit, mostly-white aesthetic of the rest of the fossil halls, the orientation gallery holding Patagotitan is mostly in near-Stygian darkness. Shoot in HDR mode if you can.
- The head poking out into the hallway is a nice trick (see also: Sauroposeidon at the Oklahoma Museum of Natural History), but it means that one of the focal bits of the animal is in a different lighting regime, which makes photography even trickier than it might otherwise have been.
- The mount feels a bit…cramped by the geometry of the room. Of the AMNH mounted sauropods, it’s easily in the worst space. If you ask me, they should have dethroned Barosaurus from the rotunda (religious commitments notwithstanding) and put Patagotitan there. The Patagotitan mount that is going in Stanley Field Hall at the Field Museum is going to look much more impressive just because of the setting.
In all, not bad, could be better. It was fun for me because the longest cervicals of Sauroposeidon are veeerrry slightly longer than the longest of Patagotitan, and now that Sauroposeidon is coming out as a titanosaur in most analyses…it might have been friggin’ immense.
So, yeah, go see Patagotitan, and all the other good stuff on display at the AMNH.
For more posts on Patagotitan, see:
“Biconcavoposeidon”
August 15, 2017
Here is a fascinating sequence of five consecutive posterior dorsal vertebra — AMNH FARB 291 from the”Big Bone Room” at the AMNH:
AMNH FARB 291, five consecutive posterior dorsal vertebrae of a probably brachiosaurid sauropod, in right lateral view. The vertebrae are embedded in a plaster block, which has been desaturated in this image.
Matt and I first saw this specimen back in February 2009, when we were mostly there to look at “Apatosarus” minimus (and then again in 2012). As soon as our eyes lit on it, we couldn’t help but be captivated by its bizarre biconcave centra. We immediately started flippantly referring to it as “Biconcavoposeidon” — the ugliest name we could come up with — and in our subsequent discussions the name has stuck (often abbreviated to “BCP”).
- Taxonomic note: for avoidance of doubt, “Biconcavoposeidon” is not and will never be a formal taxonomic name, only an informal specimen nickname. If at some future point we conclude that this specimen represents a new taxon, and name it, we will definitely not use the name “Biconcavoposeidon”. If you ever use the name, please do not set it in italics.
As you can see in this front view, the specimen is sheared: the upper part of the vertebrae have been displaced to their left (which is the right as we see it in this image):
AMNH FARB 291, most anterior of five consecutive posterior dorsal vertebrae of a probably brachiosaurid sauropod, in anterior view.
Apart from the shearing, though, and the truncation of the neural spines shortly above the transverse processes, the specimen is in pretty good nick. Crucially, it’s not been “restored” in plaster to conceal what is and is not real bone — unlike many specimens of that era. It came out of the Bone Cabin quarry in 1898, back when scientific information was routinely discarded in order to obtain a more beautiful-looking specimen.
This is the specimen that I’ll be presenting at SVPCA this year — though only as a poster, unfortunately: there’s no talk for me, Matt or Darren this year. We’ve posted our abstract (including the illustration above) to the nascent PeerJ collection for SVPCA 2017, and we’re looking forward to seeing more of the materials from that conference — abstracts, then manuscripts, then papers — appearing in the collection.
So far as we know, there’s no other sauropod specimen with biconcave posterior dorsal vertebrae. (And, no, Amphicoelias is not an exception, despite its name.) But have we missed any?
Turns out that if Mike and I don’t post about sauropods for a while, people start doing it for us! This very interesting project by Tom Johnson of Loveland, Colorado, first came to my attention when Tom emailed Mark Hallett about it and Mark kindly passed it on to me. I got in touch with Tom and asked if he’d be interested in writing it up for SV-POW!, and here it is. Many thanks to Tom for his willingness to share his work with us. Enjoy! – Matt Wedel
– – – – – – – – – – – – – – – – – – – –
The sauropod formerly known as Apatosaurus in the American Museum of Natural History was the first permanently mounted sauropod dinosaur in the world, and for many years, the most famous (Brinkman 2010). The greater part of the skeleton consists of the specimen AMNH 460 from the Nine Mile Crossing Quarry north of Como Bluff, Wyoming, supplemented with bones from other AMNH specimens from Como Bluff, Bone Cabin Quarry, and with plaster casts of the forelimbs of the holotype specimen of Brontosaurus excelsus (YPM 1980) at the Yale Peabody Museum.
A herd of Brontosaurus skeleton models parading before four box covers issued between the 1950s and 1990s.
Like many aging boomer dinophiles, my dinosaur epiphany was the result of books, movies, and toys available in the 1950s, but especially a series of plastic model dinosaur skeletons that appeared around 1958. The Brontosaurus was my personal favorite, and, like the Tyrannosaurus and Stegosaurus models in the series, was very obviously based on the AMNH mount. The models were reissued at least three times over the years and can still be found either “mint in box” or more often in various stages of completion.
Apatosaurus lousiae 1/12 scale skeleton, modelled by Phil Platt, assembled and photographed by Brant Bassam. Image courtesy of BrantWorks.com.
The crème de la crème today, of course, is the 1:12 scale Apatosaurus skeleton model by Phil Platt, available from Gaston Design in Fruita, Colorado. A particularly nice example is the one completed and mounted by Brant Bassam of BrantWorks. The Platt skeleton is a replica in the true sense of the word. The plastic models are pretty crude in comparison, as cool as they appeared to us as kids.
I was interested in skeletal illustrations I have seen of Tyrannosaurus rex, which compare the completeness of various specimens by showing the actual bones included by coloring them red. A 2005 study of Apatosaurus by Upchurch et. al. examined eleven of the most complete Apatosaurus individuals, and I was interested to see the actual bones known for each specimen. Using published descriptions, red markers, and copies of a skeletal silhouette of Apatosaurus (permission obtained from the artist), I prepared a comparison of the most completely known Apatosaurus specimens. It was clear, of course, that Apatosaurus louisae (CM 3018) is the most complete specimen of the Apatosaurus/Brontosaurus group. But it also was apparent that old AMNH 460 included a substantial portion of the skeleton, even if it is a composite.
I grabbed some additional markers and, using the illustration of the mount in William Diller Matthew’s popular book Dinosaurs (Matthew 1915, fig. 20, which I trust is in the public domain by now), I color-coded the bones according to the composition as listed in Matthew’s (1905) article:
- AMNH 460, Nine-Mile Crossing Quarry: 5th, 6th, 8th to 13th cervical vertebrae; 1st to 9th dorsal; 3rd to 19th caudal; all ribs; both coracoids; “parts of” sacrum and ilia; both ischia and pubes; left femur and astragalus; and “part of” the left fibula. RED
- AMNH 222, Como Bluff: right scapula, 10th dorsal vertebra, right femur and tibia. GREEN
(Visitors to AMNH: you can see the rest of AMNH 222 under the feet of the hunched-over Allosaurus) - AMNH 339, Bone Cabin Quarry: 20th to 40th caudal vertebrae. LIGHT BLUE
- AMNH 592, Bone Cabin Quarry: metatarsals of the right hind foot. VIOLET
- YPM 1980, Como Bluff: left scapula, forelimb long bones (casts). YELLOW
- The remaining parts of the skeleton are either modeled in plaster or are unspecified (“a few toe bones”). BLACK
It occurred to me that I might have sufficient spare parts of old ITC and Glencoe Brontosaurus models to create a three-dimensional version. I did, and painting prior to assembly definitely made the job easier.
There are obviously limitations to using Matthew’s (1915) reconstruction (e.g., only 13 cervicals) and the model (12 cervicals). It is also not clear from Matthew’s description how much of the sacrum and ilia were restored. Nevertheless, the painted model does provide a colorful, if crude, visualization of the composition of the composite.
Here are some more photos of the finished product:
A view from the front of the model, compared with a historical AMNH photo of the forelimbs and pelvic girdle.
Long considered a specimen of Brontosaurus excelsus or Apatosaurus excelsus, AMNH 460 was referred to Apatosaurus ajax by Upchurch et. al. in 2005. In the most comprehensive analysis of diplodocid phylogeny to date, Tschopp et. al. (2015) found AMNH 460 to be an “indeterminate apatosaurine” pending a “detailed analysis of the specimen.” What to call it? Oh, yeah, that’s been covered in another post!
This is a nostalgia shot for the old brontophiles. Notice that the Triceratops is entering the lake for a swim!
Tom Johnson with the mounted skeleton of Amphicyon, a Miocene “bear-dog”,
in the Raymond Alf Museum of Paleontology in Claremont, California.
References
- Brinkman , Paul D. (2010). The Second Jurassic Dinosaur Rush, University of Chicago Press, 2010.
- Matthew, William Diller, (1905). “The Mounted Skeleton of Brontosaurus,” The American Museum Journal, Vol. V, No. 2, April.
- Matthew, W.D. (1915). Dinosaurs, With Special Reference to the American Museum Collections, American Museum of Natural History, New York.
- Tschopp, Emanuel, Octávio Mateus, and Roger Benson. (2015). “A Specimen-Level Phylogenetic Analysis and Taxonomic Revision of Diplodocidae (Dinosauria, Sauropoda).” Ed. Andrew Farke. PeerJ 3 (2015): e857.
- Upchurch, P., Tomida, Y., Barrett, P.M. (2005). “A new specimen of Apatosaurus ajax (Sauropoda: Diplodocidae) from the Morrison Formation (Upper Jurassic) of Wyoming, USA”. National Science Museum Monographs (Tokyo) 26 (118): 1–156.
Is it time to rethink the private/public distinctions for museums?
October 11, 2016
Prologue
Back when I started writing about issues in scholarly publishing, I would sometimes write about the distinction between for-profit (bad) and non-profit (good) publishers. While I still recognise this as an issue, thinking it through over the last few years has made it clear that this distinction is largely orthogonal to the one that really matters — which is between open and non-open publishers.
In fact, all four quadrants exist:
| For-profit | Non-profit | |
|---|---|---|
| Open | PeerJ | PLOS |
| Non-Open | Elsevier | ACS |
ACS may be a 501(c)(3) nonprofit organization, and PeerJ may be a private company primarily owned by two individuals — but it’s PeerJ that’s pushing openness forward, and ACS doing quite the opposite.
Logue
Beautifully preserved cervical vertebra of Barosaurus in the prep. lab at the North American Museum of Ancient Life (NAMAL).
I’ve found myself thinking about this recently for two reasons.
The first is that, like anyone who works on sauropods, I’ve had involvement with specimens at the Sauriermuseum Aathal (SMA), a privately owned museum in Switzerland that holds some astonishingly beautiful and complete specimens, including the Kaatedocus holotype, SMA 0004. In particular, I’ve been invited a few times to peer-review manuscripts describing SMA specimens, and I’ve always felt conflicted about this because of the SVP’s strong position on privately held specimens.
The second thing that’s pushed me to rethink the private-public distinction has been working on Barosaurus. Our experiences with specimens have been varied. Yale University was very helpful when we went to see the holotype YPM 429, and BYU really couldn’t have done more for us on our recent visit. This is what we would hope for, of course. But what we didn’t particularly anticipate is how generous and helpful the people at the commercial fossil hunters Western Paleo Labs would be. When, visiting the North American Museum of Ancient Life, we gazed in awe through their prep. lab window at their several gorgeous Barosaurus cervicals (see photo above), they invited us in to play with them. (The vertebrae, not the people.)
And that made me think about our much less satisfactory experience trying to photograph the presacrals of AMNH 6341 at the American Museum of Natural History — they are entombed in a glass case surmounted by a not-really-transparent walkway:
Which meant that, when trying to obtain dorsal-view photographs, I had to use this technique:
With results like these:
Now I want to be clear that everyone we dealt with at the AMNH was as helpful as they could be. No-one that we met there was in any way obstructive. Yet the fact remains, the crucially important presacral verterbrae of the most widely recognised Barosaurus in the world were essentially impossible to study.
Worse: papers that have been published about those specimens are now essentially irreproducible, because the specimens are not really available for re-study — much as though they’d been sold to Nicolas Cage to display over his mantelpiece.
Whereas the Barosaurus vertebrae at Western Paleo Labs do seem to be available for study.
Hmm.
Just as we were mistaken in focussing primarily on the for-profit/non-profit distinction between publishers when what we really cared about was the open/non-open distinction, could it be that we’ve been misfocussing on the public/private ownership distinction when what we really care about is availability of specimens?
Is there a way to be confident about which museums will and will not always make specifimens available for study? Here’s where my knowledge cuts out, but one would think this would be the key element in museum certification. But then no doubt museum certification is done differently in different jurisdictions. Knowing that a German museum is accredited may tell you something completely different from knowing that an American museum is accredited.
So perhaps what we need is some globally recognised statement that any museum in the world can sign up to: formally committing to keep its specimens available to researchers; and comitting never to sell them to any party that has not also signed up to the statement.
Epilogue
It’s worth noting the Sauriermuseum Aathal seems, as far as I’ve ever heard, to have conducted itself in every way as we would wish. They seem pretty unambiguously to be among the good guys. More: they seem to have unilaterally done more or less what I advocated above: their website declares:
Declaration Concern: Holotypes of the fossil-collection of the Sauriermuseum Aathal.
The Sauriermuseum Aathal, Switzerland (SMA), is being recognized more and more as valuable scientific institution. We hereby state publicly the SMA policy concerning holotype specimens. We recognize the importance of these reference specimens for science, and strongly agree that they have to be available for science in perpetuity. Therefore, we declare that all holotypes present at the Sauriermuseum Aathal, Switzerland (and all new holotypes that will be described in future), will always be publicly accessible to all bona fide researchers, and will never be allowed to be sold to any private collection.
Are they one step ahead of us? And if so, should we cast off our reservations about publishing on their specimens?
Diplodocid sacra of the AMNH (and indeed the Carnegie Museum)
August 11, 2015
Back in 2012, when Matt and I were at the American Museum of Natural History to work on “Apatosaurus” minimus, we also photographed some other sacra for comparative purposes. One of them you’ve already seen — that of the Camarasaurus supremus holotype AMNH 5761. Here is another:
(Click through for glorious 3983 x 4488 resolution.)
This is AMNH 3532, a diplodocid sacrum with the left ilium coalesced and the right ilium helpfully missing, so we can see the structure of the sacral ribs. Top row: dorsal view, with anterior to the left; middle row, left to right: anterior, left lateral and posterior views; bottom row: right lateral view.
As a matter of fact, we’ve seen this sacrum before, too, in a photo from Matt’s much earlier AMNH visit. But only from a left dorsolateral perspective.
When we first saw this, it didn’t even occur to us that it could be anything other than good old Diplodocus. And indeed it’s a pretty good match for the same area in the CM 84/94 cast in the Museum für Naturkunde Berlin (this image extracted from Heinrich Mallison’s beautiful giant composite):
And the general narrowness of the AMNH sacrum says Diplodocus to me. But what is that expectation of narrowness based on? When I compared the AMNH specimen with Hatcher’s (1901) ventral-view illustration in his classic Diplodocus monograph, I had second thoughts:
Hatcher (1901: fig. 9). Inferior view of sacrum and ilia of Diplodocus carnegii (No. 94), one tenth natural size; pp, public peduncle; is, ischiadic peduncle; a, anterior end; p, posterior end.
That is a much wider sacrum than I’d expected from Diplodocus.
So what is going on here? Is Diplodocus a fatter-assed beast than I’d realised? I am guessing not, since my expectation of narrowness has been built up across years of looking at (if not necessarily paying much attention to) Diplodocus sacra.
So could it be that CM 94, the referred specimen that Hatcher used to make up some of the missing parts of the CM 84 mount, is not Diplodocus?
Well. That is certainly now how I expected to finish this post. Funny how blogging leads you down unexpected paths. It’s a big part of why I recommend blogging to pretty much everyone. It forces you to think down pathways that you wouldn’t otherwise wander.
References
- Hatcher, Jonathan B. 1901. Diplodocus (Marsh): its osteology, taxonomy and probable habits, with a restoration of the skeleton. Memoirs of the Carnegie Museum 1:1-63 and plates I-XIII.
In a recent post I showed some photos of the mounted apatosaurine at the American Museum of Natural History in New York, AMNH 460, which Tschopp et al. (2015) regarded as an indeterminate apatosaurine pending further study.
A lot of museums whose collections and exhibits go back to the late 19th and early 20th centuries have scale model skeletons and sculptures that were used to guide exhibit design. I have always been fascinated by these models, partly because they’re windows into another era of scientific research and science communication, and partly because they’re just cool – basically the world’s best dinosaur toys – and I covet them. In my experience, it is very, very common to find these treasures of history buried in collections, stuck up on top of specimen cabinets, or otherwise relegated to some out-of-the-way corner where they won’t be in the way. I know that exhibit space is always limited, and these old models often reflect ideas about anatomy, posture, or behavior that we now know to be mistaken. But I am always secretly thrilled when I see these old models still on exhibit.
The AMNH has a bunch of these things, because Henry Fairfield Osborn was crazy about ’em. He not only used 2D skeletal reconstructions and 3D model skeletons to guide exhibit design, he published on them – see for example his 1898 paper on models of extinct vertebrates, his 1913 paper on skeleton reconstructions of Tyrannosaurus, and his 1919 paper with Charles Mook on reconstructing Camarasaurus. That genre of scientific paper seems to have disappeared. I wonder if the time is right for a resurgence.
So in a glass case at the feet of AMNH 460 is a model – I’d guess about 1/12 or 1/15 scale – of that very skeleton. You can tell that it’s a model of that particular skeleton and not just some average apatosaur by looking carefully at the vertebrae. Apatosaurines weren’t all stamped from quite the same mold and the individual peculiarities of AMNH 460 are captured in the model. It’s an amazing piece of work.
The only bad thing about it is that – like almost everything behind glass at the AMNH – it’s very difficult to photograph without getting a recursive hell of reflections. But at least it’s out where people can see and marvel at it.
Oh, and those are the cervical vertebrae of Barosaurus behind it – Mike and I spent more time trying to look and shoot past this model than we did looking at it. But that’s not the model’s fault, those Barosaurus cervicals are just ridiculously inaccessible.
So, memo to museums: at least some of us out here are nuts about your old dinosaur models, and where there’s room to put them on exhibit, they make us happy. They also give us views of the skeletons that we can’t get otherwise, so they serve a useful education and scientific purpose. More, please.
References
Osborn, H. F. (1898). Models of extinct vertebrates. Science, New Series, 7(192): 841-845.
Osborn, H.F. (1913). Tyrannosaurus, restoration and model of the skeleton. Bulletin of the American Museum of Natural History, 32: 91-92, plates 4-6.
Osborn, H. F., & Mook, C. C. (1919). Characters and restoration of the sauropod genus Camarasaurus Cope. From type material in the Cope Collection in the American Museum of Natural History. Proceedings of the American Philosophical Society, 58(6): 386-396.
Apatosaurines on the brain right now.
I’ve been thinking about the question raised by Jerry Alpern, a volunteer tour guide at the AMNH, regarding the recent Tschopp et al. (2015) diplodocid phylogeny. Namely, if AMNH 460 is now an indeterminate apatosaurine, pending further study, what should the museum and its docents tell the public about it?
Geez, Apatosaurus, it’s not like we’re married!
I think it’s a genuinely hard problem because scientific and lay perspectives on facts and hypotheses often differ. If I say, “This animal is Apatosaurus“, that’s a fact if I’m talking about YPM 1860, the genoholotype of Apatosaurus ajax; it would continue to be a fact even if Apatosaurus was sunk into another genus (as Brontosaurus was for so long). We might call that specimen something else, but there would always be a footnote pointing out that it was still the holotype of A. ajax, even if the A. part was at least temporarily defunct – the scientific equivalent of a maiden name.* For every other specimen in the world, the statement, “This animal is Apatosaurus” is a hypothesis about relatedness, subject to further revision.
* This is going to sound kinda horrible, but when one partner in a marriage takes the other’s surname, that’s a nomenclatural hypothesis about the future of the relationship.
Apatosaurine cervicals are the best cervicals.
Fuzzy science
Things that look fairly solid and unchanging from a distance – specifically, from the perspective of the public – often (always?) turn out to be fairly fuzzy or even arbitrary upon closer inspection. Like what is Apatosaurus (beyond the holotype, I mean) – or indeed, what is a planet.** There is no absolute truth to quest for here, only categories and hypotheses that scientists have made up so that we can have constructive conversations about the crazy spectrum of possibilities that nature presents us. We try to ground those categories and hypotheses in evidence, but there will always be edge cases, and words will always break down if you push them too hard. Those of us who work on the ragged frontier of science tend to be fairly comfortable with these inescapable uncertainties, but I can understand why people might get frustrated when they just want to know what the damned dinosaur is called.
** Triton, the largest body orbiting Neptune, is almost certainly a captured Kuiper Belt object, and it’s bigger than Pluto. Moon or planet? Probably best to say a former dwarf planet currently operating as a satellite of Neptune – but that’s a mouthful (and a mindful, if you stop to think about it), not a short, convenient, easily-digestible label. Any short label is going to omit important information. This is related to the problem of paper title length – below some threshold, making something shorter means making it incomplete.
What I would say
I suppose the short version that is most faithful to the Tschopp et al. results is:
This skeleton (AMNH 460) might be Apatosaurus or Brontosaurus or a third, new thing – scientists aren’t sure yet.
A reasonable follow-up sentence – and an answer to the inevitable “Why not?” – would be:
They have to look at 477 anatomical details for lots of skeletons and weigh all the evidence, and that takes time.
Personally, if I was talking to museum visitors I would lean in conspiratorially and say:
If you want to call it Apatosaurus or Brontosaurus, go ahead – those are both ‘live’ hypotheses, and even the world’s experts on this problem can’t tell you that you’re guessing the wrong way – at least not yet.
And if there was a kid in the group, I’d add:
Maybe you’ll be the one to figure it out!
What would you say?
My neck is fat.
P.S. I wouldn’t change the signage. It could still turn out to be Apatosaurus, and the Tschopp et al. results do not lend themselves to easy label-ification.
P.P.S. With some modification for taxonomy, all of this applies to the Field Museum diplodocid FMNH P25112 as well.
Reference
(2015) A specimen-level phylogenetic analysis and taxonomic revision of Diplodocidae (Dinosauria, Sauropoda) PeerJ3:e857 https://dx.doi.org/10.7717/peerj.857
YPM 1980: Brontosaurus excelsus, the animal formerly known as Apatosaurus excelsus, the animal formerly known as Brontosaurus excelsus.
Today is a good day for sauropod science. Since we’re not getting this up until the afternoon, you’ve probably already seen that Emanuel Tschopp and colleagues have published a monstrous specimen-level phylogenetic analysis of Diplodocidae and, among other things, resurrected Brontosaurus as a valid genus. The paper is in PeerJ so you can read it for free (here).
I’ve already been pinged by lots of folks asking for my thoughts on this. I know that the return of Brontosaurus is what’s going to catapult this paper into the spotlight, but I hope what everyone takes away from it is just what a thorough piece of work it is. I’ve never seen so many phylogenetic characters illustrated so well. It sets a new standard, and anyone who wants to overturn this had better roll up their sleeves and bring a boatload of data. I’m also very, very happy that it’s open-access so everyone in the world can see it, use it, question it, tear it apart or build on it. Getting Brontosaurus back is just gravy. Although, being pro-brontosaur enough to have named a dinosaur in honor of Brontosaurus, I’m also pretty happy about that. If you need a quick guide to who’s who now, A. ajax and A. louisae are still Apatosaurus, and B. excelsus, B. yahnahpin (formerly Eobrontosaurus), and B. parvus (originally Elosaurus) are all Brontosaurus. For more details, go read the paper.
Apatosaurus lousiae CM 3018: still Apatosaurus. Photo from Wikipedia.
My personal feelings aside, a lot of people are asking how solid is this generic re-separation. I haven’t read the entire paper yet – it’s 299 pages long, for crying out loud – but the separation of Brontosaurus and Apatosaurus seems solid enough. Tschopp et al. didn’t do it lightly, they justify their decision in detail. I don’t hold with the idea that just because two taxa are sisters, means that they cannot be separated generically. As usual in phylogenetic taxonomy, it comes down to what we decide as a community constitutes “diagnosably distinct”. Tschopp et al. have actually put some thought into what that might mean here, and whether you agree with them or not, they’ve at least made all of their evidence and reasoning explicit. That’s both an opportunity and a challenge for critics: an opportunity to pin down exactly where and why you may disagree, and a challenge to do exactly that. You can’t just sit back and say, “I think the analysis is flawed” or “I wouldn’t have coded that character that way” (well, you can, but if that’s all you say, no-one is obliged to take that kind of lazy, drive-by criticism seriously). There are 477 characters here, most of them illustrated, for 81 OTUs, and a lot of post-hoc discussion of the results. So whether you agree with the authors or not, in whole or in part, both fans and critics should dig in and build on this work. Is it the last word on diplodocid taxonomy? Of course not. But it does move the field forward significantly, and the Tschopp et al. should be applauded for that.
There’s a lot more in there than just bringing back Brontosaurus. “Diplodocus” hayi is elevated to its own genus, Galeamopus. Neither of those things are super surprising. There have been rumors since the 90s at least that Brontosaurus might be coming back, and everyone has known for a while that D. hayi was a bit wonky. I was also not surprised to see Australodocus returned to Diplodocidae – when I saw the type material in 2011, it looked diplodocid to me (based on some characters I’ll have to unpack in some other post). More surprising to me are the sinking of Dinheirosaurus into Supersaurus, the finding that Tornieria is not particularly close to Diplodocus, and the uncertain positions of AMNH 460, the American Museum mount, which is an indeterminate apatosaurine pending further study, of FMNH 25112, the Field Museum “Apatosaurus”, which might not even be an apatosaurine at all(!). In several cases, Tschopp et al. come right out and say that X is going to need further study, so if you want to work on sauropods and you’re stuck for project ideas, go see what needs doing.
AMNH 460: we don’t know who this is anymore.
As I was scanning the paper again while composing the last paragraph, I almost fell down the rabbit hole. So much interesting stuff in this paper. Even if all you care about is morphology, the hundred or so figures illustrating the phylogenetic characters ought to keep you happy for a very long time. I look forward to reading through the vertebral characters in detail and seeing what I’ve been missing all these years.
I’m contractually obliged to point out that the authors chose to publish the complete peer-review history of the paper, so you can see what the editor (Andy Farke) and reviewers had to say. As always, I think this transparency (and credit for the reviewers) is great for science, and I can’t wait until it’s the norm at more journals.
FMNH 25112: what even IS that thing?
In addition to the paper, there’s also an interview with lead author Emanuel Tschopp on the PeerJ blog, and a nice shout-out for SV-POW!
Parting shot: why did Tschopp et al. get different results than anyone had previously? Because they used more specimens and more taxa – more data full stop. That’s also why their paper warrants serious consideration. It’s serious work. Let’s go stand on their shoulders.
Reference
(2015) A specimen-level phylogenetic analysis and taxonomic revision of Diplodocidae (Dinosauria, Sauropoda) PeerJ 3:e857 https://dx.doi.org/10.7717/peerj.857
Sauropod Vertebra Picture of the Week 
