Biggest sauropod ever (part.... II)

By popular demand... it's the second part of the old, old, old (ver 1) article I wrote in 2006 on the obscure and poorly known mega-sauropod Amphicoelias fragillimus. Be sure to read part I first.

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So, A. fragillimus was described in 1878 on the basis of an incomplete but enormous dorsal vertebra and the distal end of a femur [both reconstructed in the image below]. The details of these bones show that A. fragillimus was a diplodocoid, and thus related to more familiar taxa like Diplodocus and Apatosaurus. Despite its absurd size - suggesting (by comparison with other diplodocoids) a total length of 60 m - this material somehow vanished prior to 1921. Due in part to these facts (and also, perhaps, to its poorly publicised and unfamiliar-sounding - or 'crappy' - name), Amphicoelias fragillimus was to be all but forgotten in the decades that followed...

During the 1990s, little-known articles by John McIntosh (revered older statesman of sauropod research) and Greg Paul looked briefly at A. fragillimus. McIntosh (1998) went through Cope's inventories of the Garden Park discoveries (these records had been missed by Henry Osborn and Charles Mook in their 1921 review of Cope's sauropod collection) and found that, perhaps because the contents of several crates have no surviving records, the shipment of A. fragillimus to New York wasn't recorded. Paul (1994a, b) estimated the size of A. fragillimus based on the dimensions provided by Cope, suggesting (again, based on comparison with more completely known diplodocoids) a total length of 40-60 m, a weight of 100-150 tons, and that it would have been 9 m tall at the hips, and with thighs 3.8 m long [image below from here on Ultrazionale].

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The news is that, at long last, a proper reappraisal of this mysterious giant has finally appeared [UPDATE: remember that the text you're reading was written and first published in 2006]: it's a new paper by Ken Carpenter of the Denver Museum of Nature and Science, and while, sadly, it doesn't report the discovery of a new, articulated A. fragillimus specimen, it does cover pretty much everything we know about this dinosaur (Carpenter 2006). By the way, Carpenter and colleagues have tried looking for additional remains of A. fragillimus, thus far without success. Actually, I have to note here the rumour that new A. fragillimus material has been discovered, and that it will be discussed at the 2008 Society of Vertebrate Paleontology meeting [UPDATE: here we are, two years later... and, needless to say, this never happened].

Was A. fragillimus a hoax?

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Unsurprisingly, quite a few people have been sceptical about the existence of this all-too-conveniently lost mega-sauropod. Can we be sure that it ever really existed, or could it be that Cope was pulling a fast one in order to beat his rival, Othniel Charles Marsh [shown here], hands-down in an effort to describe the biggest sauropod? As attractive as this scenario might appear, hoaxing is highly, highly unlikely. Consider the following:-

-- Cope was very specific about all the discovery details of A. fragillimus. According to his field notes, it was collected in late 1877 by Oramel Lucas (described by Cope as his 'indefatigable friend') at Garden Park, specifically from quarry III, a site southwest of the hill known today as Cope's Nipple (Carpenter 2006). The rocks here yielded several other particularly large Morrison Formation dinosaurs (such as Camarasaurus supremus).

-- Furthermore, the shipment records discovered by McIntosh show that Oramel Lucas and his brother Ira knew of A. fragillimus and labelled some remains with this name (McIntosh 1998, p. 487 and p. 498). If it was a hoax, then the Lucas brothers must have been in on it too, which now makes it a conspiracy.

-- The conspiracy would have to extend even further, as an American Museum of Natural History catalogue number, AMNH 5777, was reserved for the A. fragillimus material.

-- The rivalry that existed between Cope and Marsh is also relevant here. As is well known, Marsh enjoyed making a very public fool of Cope when he made a technical error (Storrs 1994, Davidson 2002), and when he disagreed with Cope, or thought him wrong, Marsh was tediously pedantic in his criticisms (see Marsh's 1873 papers on dinoceratans, for example). Marsh never criticised, nor even questioned, the reality of A. fragillimus. Carpenter (2006) notes that 'Marsh is known to have employed spies to keep tabs on what Cope was collecting, and it is quite possible that he had independent confirmation for the immense size of A. fragillimus' (p. 134).

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-- Cope's drawing of A. fragillimus is accurate-looking and elaborate, and his description refers to small detailed features, all of which conform in details with what we know of diplodocoid vertebrae (part of the description is reproduced at left: from here). He would have to have made all of this stuff up if the specimen was a hoax: it's not as if the only record of A. fragillimus is a scribbled fragment in a diary, saying 'On Tuesday I saw the biggest vertebra ever... it was thiiiiis big...'. Rather, the material is documented, in detail, in a proper technical paper. To hoax an entire paper of this sort would be severe science-crime, and there is no indication that Cope was unscrupulous or dastardly, or prepared to stoop this low.

-- It is noteworthy that workers well known for their methodical and conservative approach to sauropod studies (notably John McIntosh) have accepted Cope at his word. Osborn, who succeeded Cope as vertebrate palaeontologist for the US Geological Survey and is well known for speaking his mind when he had a problem with something, also never voiced doubts about A. fragillimus.

All of this is circumstantial, for sure, but I agree with Carpenter (and others) that the idea of Cope perpetrating a hoax of this magnitude is pretty much unthinkable. I think we have to assume that the specimens really existed. Therefore, they must have become lost or destroyed some time between 1878 (their discovery date) and 1921 (when Osborn and Mook failed to find them). As Carpenter (2006) points out, it in fact appears likely that the material was too fragile to survive, and that it crumbled to bits some time after its discovery. Matt Celeskey also noted this possibility. Cope commented on this fragility, writing 'in the extreme tenuity of all its parts, this vertebra exceeds this type of those already described, so that much care was requisite to secure its preservation' (p. 563), and his drawing also suggests that the vertebra had been subjected to extensive weathering and hence was already fragile. Indeed its fragile nature explains the specific name he chose for it.

Furthermore, 'preservatives had not yet been employed to harden fossil bones, the first of which was a sodium silicate solution used in O. C. Marsh's preparation lab at Yale University beginning in the early 1880s' (Carpenter 2006, p. 134). Support for the hypothesis that the material simply did not survive collection and storage comes from the fact that, within recent years, a Camarasaurus supremus vertebra collected from the same area is known to have crumbled into small useless fragments.

The other Amphicoelias

As I've now mentioned a few times, the detailed anatomy of the A. fragillimus vertebra (as figured by Cope) shows us that this sauropod was a diplodocoid. We can make a confident statement like this because it is relatively easy to distinguish the different sauropod clades on the basis of their vertebral anatomy, and A. fragillimus has all the distinctive anatomical features typical of diplodocoids. In fact it strongly resembles the vertebrae of the first named species of Amphicoelias, A. altus, which Cope described in February 1878.

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A. altus is poorly known, but not as poorly known as A. fragillimus: it was first described for vertebrae, a pubic bone and a femur (Cope 1878), but a scapula, coracoid, ulna and partial skull were later referred to it. Based on these remains, it seems that A. altus was similar in size to Diplodocus carnegii and probably around 25 m long (Paul 1994a, b). It's particularly interesting in that its femora were markedly elongate and slender. Some workers have regarded A. altus as particularly close to Diplodocus, in which case it would be a diplodocid diplodocoid, and probably a diplodocine diplodocid diplodocoid. However, it has also been asserted that A. altus was a basal diplodocoid, and thus more archaic than diplodocids and other flagellicaudatan diplodocoids [adjacent image shows Diplodocus mount at Denver Museum of Nature and Science].

Was Cope right in referring his second Amphicoelias species to the same genus as the first? Several authors have thought so, and in fact have gone so far as to state that 'it is doubtful ... if the characters described by Cope warrant the placing of the type [of A. fragillimus] in another species different from A. altus' (Osborn & Mook 1921, p. 279), or 'there is no reason not to consider [A. fragillimus] a very large individual of A. altus' (McIntosh 1998, p. 502). If this is true then, like A. altus, it's reasonable to assume that A. fragillimus was also superficially Diplodocus-like, and with particularly elongate, slender femora (a shocking idea given the animal's size).

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Carpenter argued in his 2006 paper that, in fact, A. fragillimus seems to have differed from A. altus in a number of anatomical details, and that the two might not have been congeneric after all. As he noted, this remains untestable in the absence of better remains however. Let's all hope and pray that a new generic name is up for grabs, and I don't want any 'superlative + saurus' nominations.

One final thing. What's with the image at the top of the page? I discovered it while googling Amphicoelias. Huh, in my day the only decent zoid was Hellrunner. The image at left is mostly irrelevant: that's Matt Wedel, and he is indeed posing with a diplodocoid vertebra... although it's not from an Amphicoelias.

For previous Tet Zoo posts on sauropods see...

And - if you're serious about sauropods - you really should be spending more time at SV-POW!

Refs - -

Carpenter, K. 2006. Biggest of the big: a critical re-evaluation of the mega-sauropod Amphicoelias fragillimus Cope, 1878. New Mexico Museum of Natural History and Science, Bulletin 36, 131-137.

Cope, E. D. 1878. On the saurians recently discovered in the Dakota Beds of Colorado. The American Naturalist 12 (2), 71-85.

Davidson, J. P. 2002. Bonehead mistakes: the backround in scientific literature and illustrations for Edward Drinker Cope's first restoration of Elasmosaurus platyurus. Proceedings of the Academy of Natural Sciences of Philadelphia 152, 215-240.

McIntosh, J. S. 1998. New information about the Cope collection of sauropods from Garden Park, Colorado. Modern Geology 23, 481-506.

Osborn, H. F. & Mook, C. C. 1921. Camarasaurus, Amphicoelias and other sauropods of Cope. Memoirs of the American Museum of Natural History, n.s. 3, 247-287.

Paul, G. S. 1994a. Big sauropods - really, really big sauropods. The Dinosaur Report Fall 1994, 12-13.

- . 1994b. Is Garden Park home to the world's largest known land animal? Tracks in Time 4 (5), 1.

Storrs, G. W. 1984. Elasmosaurus platyurus and a page from the Cope-Marsh war. Discovery 17 (2), 25-27.

More like this

I remember reading in a book about the Dana Quarry in Wyoming that a new discovery was made in the spring of 2008 regarding new bones belonging to A. alta. I think Robert Bakker made the ID, but I can't be fully sure. I also don't think that the material was described yet. Hopefully though this promises to be a great discovery.

By Daniel N. (not verified) on 06 Jan 2010 #permalink

One Saturday morning (last year), I turned on the TV and found a cartoon featuring dinosaur trading cards, which could be used to summon dinosaurs. One of them, which seemed tyrannosaurish, was also capable of breathing huge beams of fire.

Giving a huge, powerful and aggressive dinosaur firebeams seemed somewhat excessive to me. Not sure if the show included any hadrosaurs with infrasound attacks, though.

Marsh never criticised, nor even questioned, the reality of A. fragillimus.

But did he actually ever say anything at all about Cope's discovery publicly, or did he damn it by silence?

Being the author of the drawing from the blog "Ultrazionale", I would note that my reconstruction of _A. fragillimus_ vertebra differs from Carpenter's one in producing a 45m long sauropod instead of the (for me too long) 58m produced by Carpenter.
I noticed that _A. fragillimus_ was not a mere linear expansion of _Diplodocus_: it seems proportionally very taller but not very broader. So, in my opinion, using the height of the neural arch of _A. fragillimus_ would produce a longer animal than using the width: this may explain why Carpenter's animal is 58m long, whereas in my reconstruction it is "only" 45m long.
I'm not a sauropod expert, so I (and my drawing) could be totally wrong.
Final frivolous note: the human silhouette in the _A. fragillimus_ femur and vertebra reconstruction is myself.

I rather like Amphicoelias as a name - it's far better than the countless unmemorableo-saurus titanosaurs that have been named recently and is no Opisthocoelicaudia. Having said that I do rather like the something-titan names.

Hellrunner wasn't the only cool early Zoid what about Spiderzoid and the big Styracosaur one. And of course who could not love Zoidzilla?

By RStretton (not verified) on 07 Jan 2010 #permalink

I find that I have come to prefer a silhouette of Mat(t) Wedel as a scale indicator for sauropod features.

By Nathan Myers (not verified) on 07 Jan 2010 #permalink

I'm sorry, but that picture was made before Matt has become the standard silhouette for sauropod reconstructions. I promise to follow the standard in future big sauropod images! ;-)

Being the author of the drawing from the blog "Ultrazionale", I would note that my reconstruction of _A. fragillimus_ vertebra differs from Carpenter's one in producing a 45m long sauropod instead of the (for me too long) 58m produced by Carpenter.

I notice you kept Cope's centrum reconstruction. Such a centrum would be much too small (and, additionally, too narrow) for such a huge neural arch. I think Carpenter's is more realistic, and Cope actually understated the size of the complete vertebra.

By David MarjanoviÄ (not verified) on 07 Jan 2010 #permalink

If it does turn out Amphicoelias fragillimus has to be renamed,how about this - Osteocolossus mysteriosus, or the "mysterious giant-boned one."

By gray Stanback (not verified) on 07 Jan 2010 #permalink

Someone suggested Saurotheos which I thought was rather neat.

By Andreas Johansson (not verified) on 07 Jan 2010 #permalink

Andrea: As in so many matters paleontological, given a slightly different sequence of historical accidents, it could easily have gone the other way. A silhouette of a sauropod descendant named Andrea might have been the standard for measuring fossilized fragments of Wedelopods.

By Nathan Myers (not verified) on 07 Jan 2010 #permalink

I would go with *Eccebehemoth* (both Cs hard) if I was honored with the privilege to name such a beast. It's a line from the Latin Vulgate (Job 40:15). "Behold now behemoth," is how the KJV puts it. I like how the name is not just descriptive, but it's also an exhortation to marvel at it.

BTW, that name's available to anyone who's sitting on an undescribed massive sauropod and willing to tag the specific epithet "maynardi" at the end of it. ;)

if its a conspiracy, does that mean we now have an inkling of what _National Treasure_ III will be about?

in other news, I hope new information comes to light in favor of at least Amphicoelias species having existed.

By Anthony Docimo (not verified) on 07 Jan 2010 #permalink

I need to think of a good name....

Maybe Gigantobestia behemotoides?
Or dare I say it "Terrestricetus"? ;)

What would latin for "Ground Crusher" be? Whever I see these things I can't help but imagine them accidentally or defensively stepping on predators that irritated them.

By Tim Morris (not verified) on 07 Jan 2010 #permalink

Tim Morris asks:

What would latin for "Ground Crusher" be?

Latin would be something like "humifragus". Greek would be "chthonothraustes".

Okay, so humifragus is out, everyone would think it had something to do with jim-henson...(fraggus etc)

By Tim Morris (not verified) on 07 Jan 2010 #permalink

Abyssal:

I would go with *Eccebehemoth* (both Cs hard) if I was honored with the privilege to name such a beast. It's a line from the Latin Vulgate (Job 40:15). "Behold now behemoth," is how the KJV puts it. I like how the name is not just descriptive, but it's also an exhortation to marvel at it.

Naming a dinosaur 'behemoth' (or 'leviathan', for that matter) would be a bad idea*. Creationists would use that in their propaganda and claim that it supports their belief that humans and dinosaurs once lived side by side. 'See? Even the godless scientists now admit that the biblical behemoth really was a dinosaur and not a hippopotamus!' That's how they would twist it, believe you me.

* Naming a fossil species of hippopotamus 'behemoth' could, on the other hand, almost be something worth doing.

Osteocolossus mysteriosus, or the "mysterious giant-boned one."

No, that would mean "bone statue", not "giant-boned".

Too bad Megistotherium ("biggest beast") is preoccupied. Megistozoon could run into trouble because many whales are heavierâ¦

Someone suggested Saurotheos which I thought was rather neat.

That's how you can call a 20-m-long mosasaur. I don't want yet another lizard reference in a dinosaur.

Incidentally, "leviathan" probably meant "crocodile".

By David MarjanoviÄ (not verified) on 08 Jan 2010 #permalink

David:

Incidentally, "leviathan" probably meant "crocodile".

That's one interpretation. Here is another. Be warned that teh stoopid really, really burns on that page. (Amphicoelias, by the way, is also mentioned there.)

I do hope they find some more remains of this fantastic
creature, what ever you fellows wind up calling it.

Iron Kong, however, is by far the coolest Zoid.

By Craig York (not verified) on 08 Jan 2010 #permalink

I was not familiar with A fragllimus.i did know of the Marsh Cope Bone wars.For years i was of the opinion that Diplodocus and Brontosaurus were the largest of all sauropods.Every one should buy your book " The Great Dinosaur discoveries:.

By Bob Michaels (not verified) on 08 Jan 2010 #permalink

That's how you can call a 20-m-long mosasaur. I don't want yet another lizard reference in a dinosaur.

I'd argue that as far as taxonomy is concerned, the root "saur" stopped meaning lizard long ago. It effectively means something like reptilish animal.

By Andreas Johansson (not verified) on 08 Jan 2010 #permalink

Naming a dinosaur 'behemoth' (or 'leviathan', for that matter) would be a bad idea*. Creationists would use that in their propaganda and claim that it supports their belief that humans and dinosaurs once lived side by side. 'See? Even the godless scientists now admit that the biblical behemoth really was a dinosaur and not a hippopotamus!' That's how they would twist it, believe you me.

Who gives a sh*t? I don't pay any mind to creationists and couldn't care less what they use in their propaganda. Propaganda which would look pretty much the same whether or not I got to pick my choice of name for a gigantic sauropod.

* Naming a fossil species of hippopotamus 'behemoth' could, on the other hand, almost be something worth doing.

There is already a species of Hippopotamus called H. behemoth. It was Israeli, fittingly enough.

It effectively means something like reptilish animal.

That's almost worse! :-) Long live Ornithopsis!

By David MarjanoviÄ (not verified) on 08 Jan 2010 #permalink

(I mean, it's dead... but...)

By David MarjanoviÄ (not verified) on 08 Jan 2010 #permalink

"Someone suggested Saurotheos which I thought was rather neat."
"That's how you can call a 20-m-long mosasaur. I don't want yet another lizard reference in a dinosaur."

But it's close enough to my old nominee for a new name:
_Brontodeus_

Megistoposeidon perhaps?

(Anything with megisto- or another superlative would be an especially good choice because cosmic irony would then dictate the discovery of an even LARGER sauropod...)

By William Miller (not verified) on 08 Jan 2010 #permalink

Abyssal:

I don't pay any mind to creationists and couldn't care less what they use in their propaganda.

Well, both Stephen Jay Gould and Niles Eldredge were throughout their careers highly annoyed and frustrated at constantly finding their punctuated equilibrium hypothesis hijacked - and grossly misrepresented - by the creationists. Unless you're an exceptionally thick-skinned person, I suspect that you too, in the long run, would feel rather miffed about seeing your "Eccebehemoth" (as well as your own name, by association) being touted as evidence against evolution.

There is already a species of Hippopotamus called H. behemoth. It was Israeli, fittingly enough.

That I didn't know. Interesting! Light googling suggests that this species was named in Faure (1986)*. I don't have access to that publication; what does Faure say about the etymology?

* The full reference, unless I'm much mistaken, is:

Faure, M. 1986. Les hippopotamides du Pléistocene ancien d'Oubeidiyeh (Israel). In: Tchernov, E. (ed.) Les Mammifères du Pleistocene Inférieur de la Faille du Jourdain à Oubeidiyeh, Association Paléorient, Paris, pp. 107-142.

hippopotamidés, Pléistocène.

Never even heard of that journal.

By David MarjanoviÄ (not verified) on 11 Jan 2010 #permalink

David:

Never even heard of that journal.

Isn't it a book/monograph?

Never mind my previous question; it seems to be this publication.

Ah, so "Association Paléorient" is the publisher rather than the abbreviated name of a journal, and the thing is a bookâ¦

By David MarjanoviÄ (not verified) on 11 Jan 2010 #permalink

Does anyone know if the NHM display with Othniel's face has his name spelt correctly yet? It was misspelt 'Othneil' last time I looked.
://s98.photobucket.com/albums/l260/armadillozenith/?action=view&current=Othneilwrong100.jpg
Just put http in front of that link.

You know I've been thinking the same stuff. I've been thinking, have those giddy paleontologists trying to lie to each other, about their finds?
For one thing, Argentinosaurus himself has been downweighed to 100 or 70 tons, and then, on Ben Creisler's Mosasauria Pronunciation and Translation Guide, I spotted something about Pythonomorpha, and on Clidastes.
Cope had written that (I'm obviously sharing my thoughts about the idea, not Cope's original words) pythonomorphs could stretch hundred feet long, and that they were huge, snaky-type things, which coiled around and around....
OKAY...Then we come to the fact that mosadsaurs were fishy-croc-like,or-ichthyosaur-looking animals, and then to Mosasaurus hoffmanni and Tylosaurus Proriger; the two of them were the biggest, and were slightly over 50 feet in Masa's case.
Okay, then I thought, if this guy could make a mistake of that sort, put Elasmo's head on his tail and then...get into debts in the end, finally, couldn't he have the guts to fake a fossil. It's my idea, and if you've checked my post on marine reptile summer, with Bob Nicholl's pics, you might know....

By Dinosaurzzz (not verified) on 11 Sep 2010 #permalink

couldn't he have the guts to fake a fossil.

It's very unlikely that it's fictitious. The description doesn't read suspicious at all, and the stippled lines where the ends of the neural arch and the entire centrum are broken off are too small.

By David MarjanoviÄ (not verified) on 12 Sep 2010 #permalink