FORGOTTEN GIANTS, #1: Puertasaurus

Posted by Nima On Monday, March 8, 2010 30 comments

Ahoy there, dinosaur fans! After much anticipation and work, I am proud to announce the first installment of my new Sauropod reconstruction series:


Forgotten Giants will focus exclusively on titanosaurs and their closest basal relatives. And the first "episode" in this series is the largest of them all - Puertasaurus reuili. It's also apparently the widest and most massive, but one of the least understood - so let's get started. Here's the (not so) skinny on the NEW "biggest dinosaur".

A giant among giants

Discovered only in 2005, Puertasaurus is not just huge. It's not just gigantic. It's literally a record-smasher. Whereas other titanosaurs may have approached or reached the 100-foot (30m) mark, Puertasaurus, even by conservative estimates, easily exceeded it by at least a few meters. Though it's only known from four vertebrae, their huge size points to a creature large enough to possibly rival even the enigmatic Amphicoelias fragillimus.

 

Diagram of giant sauropod dorsal vertebrae in frontal view (taken from the Hairy Museum of Natural History)
 (a) The diplodocid Seismosaurus hallorum, dorsal 8 (after Herne and Lucas 2006)
(b) The diplodocid Amphicoelias fragillimus, dorsal 9/10? as reconstructed by Cope 1878,
(c) Amphicoelias fragillimus dorsal 9/10? as restored by Carpenter 2006, after A. altus 
(d) Amphicoelias altus dorsal 10? (Carpenter 2006, modified from Osborn & Mook 1921),
(e) Puertasaurus reuili dorsal 2 after Novas et al 2005, Figure 2). Scale bar equals 1 meter.

The dorsal from Puertasaurus is far wider than even the reconstructed dorsal of A. fragillimus - but far less tall. This was a squat, wide titanosaur, whereas A. fragillimus, despite its size, was a proportionally slim, deep-bodied diplodocid. And for human scale.....


Here's Dr. Fernando Novas, who described and named the new sauropod Puertasaurus reuili, after the two farmers, Puerta and Reuil, who first discovered the remains. This is just a taste of how big this animal was - the bone makes entry impossible through an otherwise decent-sized university office - and from what I've heard, Novas is a tall man, around 6 feet or so. As you can see, the dorsal vertebra had to be reassembled from its fragments, but most of it is there. Note the picture on the computer monitor - more on that later.


Here's the same dorsal (D2) from the front, viewed in an exhibit. The other remains known from Puertasaurus are a cervical vertebra (probably the ninth) and two caudals that have not been published (the reason for this is unknown, and it's a shame they weren't published in Novas' paper, as they would have yielded valuable information about how the tail should be restored).

A little note on this dinosaur's family tree - even the few bones found so far indicate that it's a member of the family Lognkosauria, an intermediate group of titanosaurs that evolved in the mid-cretaceous, and are more derived than the Andesauridae (such as Argentinosaurus) but more basal than the Saltasaurs and Antarctosaurs that replaced them toward the end of the Cretaceous. Lognkosaurs are not very well known (in fact, there are only three other confirmed genera in the family) but they were present in both South America and Africa, and all share a very robust build, huge cervical rib loops, massive neural spines, and very long necks that are either unusually wide, deep, or both. These are the Gothic cathedrals of the Titanosauria. What's interesting about Puertasaurus in particular, is that it appeared much later than the other Lognkosaurs. Most of them date from the mid-Cretaceous, in the Albian, Cenomanian, and Turonian epochs (roughly from 110 to 90 million years ago), but Puertasaurus stomped onto the scene very late, in the Maastrichtian epoch - the very end of the Late Cretaceous, 70-65 million years ago, a time when T. rex was already roaming Montana thousands of miles to the north, a time when practically every sauropod was a titanosaur, and only one (Alamosaurus) made its home in North America, a land that was then mostly swamps and inland seas - not too sauropod-friendly - but was gradually becoming drier and more hospitable to the giants. Alamosaurus itself was a saltasaur with South American ancestors, and probably migrated north across the land bridge that was rapidly forming between the two continents in the Late Cretaceous.

Now given that Puertasaurus is such a new dinosaur, it's understandable there's never been a truly high-fidelity illustration of it. In fact there have only been two complete life illustrations done in non-digital media, both by Gabriel Lio. Though why this animal is not as popular with both artists and the public as Argentinosaurus, despite almost certainly being larger, is a bit of a puzzle.


The first Gabriel Lio (?) painting of Puertasaurus shows a rather small-looking and short-necked sauropod dwarfed by what appears to be an oak tree on the left. Not only is the presence of a huge oak tree dubious for Cretaceous Argentina (where conifers, like those in the background, dominated the flora), but it also greatly under-emphasizes the size of this animal. It's not too far from those little running ornithopods, yet it looks strangely small relative to their scale. Even a modest-sized Apatosaurus should be bigger than this relative to those little buggers. What's more, the primitive "generic long-neck" head and the not-so-long neck combined with a fairly nondescript body and tail, make this guy look more like an a boring 50-foot cetiosaur than a record-breaking titanosaur that challenges A. fragillimus for sheer size.


Here's the second painting by Gabriel Lio, incorporated into a magazine diagram on the new discovery. It's the same image on Fernando Novas' computer screen in the earlier picture, and was published on many websites that announced the new discovery - ironic, since this illustration isn't all that scientific. Here we get a highly exaggerated, Marvel comic-like picture, with again an unusually short neck, Donald Duck-like jaws, a torso so short that the hands touch the feet in backstride, an inward-twisted left hand whose angle looks like a nightmare wrist sprain in the making, oversized hands and feet, long and dislocated toes, and bulging arms and legs built more for tackle football than for simple graviportal walking. Believe it or not, it actually does not take huge bulging muscles to move a sauropod-sized body at a slow pace. Ceratopsians on the other hand, had enormous muscle crests and scars on their short limbs, as do galloping rhinos today - moving fast requires proportionally more muscle than moving mass. Add to this the furious snarling facial expression (did sauropod even HAVE facial expressions? Even most herbivorous mammals today don't, despite having muscular faces), and you basically have a 100-ton monster with earthquake-inducing roid rage. Of course it could just as easily be a 6-ton wimp. It's got the proportions (however pumped up) of a short-necked dwarf sauropod.

In an attempt to draw a more believable Puertasaurus (and one that actually LOOKS like it has the proportions of a hundred-foot-plus sauropod), as well as one that had the recognizable features indicated by its bones, I started with the actual published material. As I think visually, I could see no essential connection between the actual bones and what Gabriel Lio has drawn (not that I doubt his actual talent as an artist in any way - but his art is heavily exaggerated and comic-ized, and much of it just isn't too terribly scientific). Thus I went purely by the bones and by those of Puertasaurus's better-known relatives. Extrapolating based on the length of the published ninth cervical vertebra and a general rule of 15 cervicals, most of roughly similar length, for titanosaurs, I ended up with a far longer neck than Gabriel Lio illustrated. One wonders if he actually went off of Novas' published figures and measurements, or just drew his fanciful sauropod 100% from imagination and called it Puertasaurus.

In making a truly accurate Puertasaurus restoration (as much as is possible given that there are only four bones found, and only two of them have been published), one of my aims was to include scale drawings of the described bones, dorsal D2 and cervical C9, as they would have appeared when complete and uncrushed. Novas et. al. included a smooth pencil drawing of the 'reconstructed' D2 but did not put in one for C9 - the only visual diagrams of C9 are a few line drawings and a set of four grainy photos of the incomplete vertebra, only partially reconstructed, with the rear of the neural arch and the proximal arches of the cervical ribs incomplete. D2 was easy to draw, but C9 posed a real challenge.The long portion of the cervical ribs was also absent, so I drew them as they may have looked based on the proportions of cervical ribs on other titanosaurs and titanosauriformes (primarily Rapetosaurus and Uberabatitan, but looking at a a few Giraffatitan pics didn't hurt).

This ended up being a triple view restoration, much like Gregory Paul does with skeletal diagrams. I mainly did multiple views of the body to give some idea of its likely 3D form. Though to my knowledge, no artist before has regularly done life restorations in multiple view. This may be the first example.

Late in the process of drawing it, I got the idea to include the largest known predatory dinosaur, Giganotosaurus carolinii (incidentally also from Argentina, but from an earlier time) for scale. Now there's a real idea of the vast scale of Puertasaurus, a sauropod so colossal that even the largest meat-eaters barely came up to its knee. And yes, T. rex was even smaller.


This first restoration was somewhat messy and smudged, but already it's possible to get a grasp of what this animal may well have looked like in life. The torso is incredibly wide, and I drew it that way for a reason - the dorsal vertebra D2 is freakishly wide - much wider than it is tall. Novas published a width measurement of 1.68m for this bone, and accounting for crushing, erosion, and edgewise damage, I arrived at a maximum restored width of just under 2m. In particular, the wing-like diapophyses are enlarged far beyond those of any other sauropod, even other wide-bodied titanosaurs. The expanded processes must have supported a very wide and massive rib cage, and then when you consider that D2 is only the second dorsal, and that the dorsals further back have much wider ribs in all sauropods, then it's not too hard to see that the maximum width was record-breaking. With multiple scaling attempts, I arrived at a fairly radical 7.5m width at the rib cage's widest point (which would probably be around dorsal 8 or 9).

Also note the extreme width of C9, especially the cervical ribs. The neck was proportionately squat rather than deep, and this probably culminated in a wide, flattened head (as well as potentially resulting in a very extreme vertical range of motion for the neck). In terms of proportions, it's already clear even based on these two published bones, that this is not just one of the biggest sauropods, but also one of the weirdest.

Next there was some pretty standard digital refining, cleanup, and color adjustment.


Then I labeled everything, including the described bones. And I also added the human figure for scale.


However this image had a few problems - the most obviously glaring one is the top view of the cervical C9. There neural spine is one thin ridge, and the neural arch below and around it looks flat. And suddenly I realized this was not accurate. I went back and consulted the original photos of this bone in Novas et. al. 2005.

 
Images of Puertasaurus cervical C9 from Novas et. al. 2005:
A: frontal view
B: left side view
C: top view
D: ventral (bottom) view

Notice that the neural spine as seen in (A) is quite wide and robust. It's either partially wrapped in plaster or heavily reconstructed, but the visible dark portion on the right of the neural spine in (A) indicates the extent of the spine's true width. From the top, in (C) the actual contours of the spine are very hard to discern due to all the white plaster. However, from the bony margins and shadows of the spine, it's very evident that this is a much wider structure than I had drawn. So I altered it and added shading to the image of C9, since a simple outline drawing would not show the gradual anterior slope of the spine or the pit in front of it. The result is a much more robust and complex design with both curves and angular features.



This was the version that made it to the ArtEvolved Sauropod gallery, and later was featured on SV-POW (kudos to the SV-POWsketeers for hosting the detailed and enlightened discussion that followed).

Yet I decided this restoration was still missing an important element - a frontal view of C9. I went back to the photos from paper for reference, and fixed the symmetry to remove the crushing (which is minimal but asymmetric). Then I reconstructed the missing portions (mainly the neural arch and the upper portions of the proximal arches of the cervical ribs, these are drawn less massive than in the line drawings in Novas et.al.). I also drew a rough outline of the neck circumference, lightly muscled, as in real life the vertebra was internally pneumatic. I also added complete proximal arches in the other views on C9. This frontal view was drawn and scanned separately and re-sized to fit the scale of the Puertasaurus.


One more main change remained: the upper jaw line looked a bit too straight to belong to a late-cretaceous titanosaur. I did not want to make it as scooped out as that of Antarctosaurus or the saltasaurids, but more so that its previous primitive-looking shallow curve. The improvement is consistent with the general assumption that the heads of Lognkosaurians would have had a shape somewhere between basal titanosaurs/titanosauriforms and saltasaurs. Also I changed the circumference outline on the frontal view of C9 to show more room for the neck ligament on the neural spine. The final result is below.



The final product: 130 feet of pure sauropod awesomeness. The head alone would have been big enough to swallow something the size of a very large man. And the claws on its feet could take out even a Giganotosaurus-sized predator in one blow. And if the rib cage had been preserved, you could probably shove a couple of Hummers in there without too much trouble. It's not a beast most dinosaurs would ever want to mess with (or could, for that matter, even if they wanted to!)


* Epilogue: The paleo-artist known as "Rexisto" used my Puertasaurus as the basis for many of his revised mega-titanosaur silhouettes, mistakenly claiming that my restoration was world-renowned paleoartist Greg Paul's work! While I took this as a HUGE compliment, unfortunately it means that Rexisto didn't ask permission to use my work, but after I pointed this out to him, he apologized and I accepted his apology since it was just a misunderstanding due to language barriers, and because his silhouette work is non-commercial in nature. But in the future, people, please ASK me if you want to base your work on mine, in most cases I'll be totally cool with it as long as you ask me first - it's the same thing I do when I want to re-interpret another artist's work (as I did in the case of "remixing" John Conway's Chasmosaurus - see my finished version HERE), and I'd appreciate it if everyone else does the same. And if you just want to re-post my images on your blog, that's fine, but please be professional and give me proper credit. If your English is not so good, email me anyway, I'll deal with translating and replying to it. It's not that hard. Read my TERMS OF USE on the right sidebar, or even just the little blurb under the blog title. You have been warned.

UPDATE: Rexisto has made a correction on the Mesozoico forums to credit me as the creator of the work he based his silhouettes on. Here's the link. Thanx, Rexisto!

Peace out :) And by all means, share your thoughts on the Puertasaurus!

30 comments:

davidmaas said...

This thing is begging to be animated. [finger itches, phone rings, client nags]
One day!

Fantastic pwork, Nima.

Anonymous said...

Thanks Nima for your comments and drawings on the Puertasaurus discovery. I have been following your interest and debates about this dinosaur since last November.
When I first read the Novas paper the compelling morphology coupled with the size of the Puertaaurus bones made even a non scientist like myself wonder and wonder what it was like and your ongoing discoveries and evaluations have kept its unique appeal fresh.
I became interested in Dinosaurs at a young age through my parents buying me the Prehistoric Animals and Prehistoric Man books by Augusta and Burian. This kind of fine quality writing and art was enough to promote a lifetime interest in me. I noticed that Eroll Fuller mentions the same kind of inspiration for the attention and care he took in writing his book Extinct Birds.
The greatest example of depicting pure mass I have seen in prehistoric artwork was the Brontosaurus picture by Charles Knight. Despite his exagerations of the sheer size which I guess are 50-100% it remains one of those hard to forget images.
I realize you have a very different style than Knight who used modulations to convey his sense of mass. He was an expert in this. Your own style is much appreciated.
Keep up the good work

Nima said...

Thanks for the compliments!

David, I'd be honored to see you animate or 3D render my Puertasaurus. Your work is amazing, and doing a 3D model of this guy would really give an idea of the size and depth of this amazing creature.

Anonymous, thank you too. I myself grew up reading a lot of old books with illustrations by Knight and Zallinger, and while they had lots of anatomical problems, they DID spark my interest in dinosaurs, much the same way that a really good nature show will get kids fascinated by jungles and tigers.

I'm not entirely sure what you mean by modulations, but basically Knight was a "romantic" or a dramatist painter, i.e. he wanted to capture the emotion of a scene more than the accuracy. Thus you get epic "hard-to-forget" dinosaur scenes like his T.rex vs. Triceratops, which is probably the most famous dinosaur painting of all time. Burian was similar in style. They both preferred drama over accuracy and didn't really care too much for rigorous measurements and skeletal drawings, what's more, the skeletals of those days were pretty shabby. As long as they had the length right, the proportions and bulk didn't matter too much. The only live animals the bothered to study for reference were stubby-legged crocodiles and turtles, thus it's no surprise their dinosaurs ended up sprawling and squat like crocodiles and turtles.

A lot of newer artists (including myself) are more like "neo classicists", i.e. rigorous measurements combined with a dynamic and elegant aesthetic like Renaissance painters, as opposed to the rigid flat caricatures of medieval times. Thus, we do a lot more scale drawings, anatomical sketches and the like, before drawing a scene, so that the dinosaurs actually look true to the fossils. And we tend to reference bird and mammal anatomy too, not just reptiles. Physiologically, dinosaur bodies were much more similar to an elephant, an ostrich, or a rhino than a crocodile.

While the old artists like Knight focused on making dinosaurs basically huge plodding blob monsters to excite the imagination of a sideshow-interested public, I try to focus on what was the most efficient and plausible appearance for them given the bone design, and what movements they WERE capable of. Generally I avoid over-bulking dinosaurs like Knight did, especially the ones that are already very big. Also considering that if you're that big, you have to be eating and migrating for food all the time to fuel your body, so on a typical day a lot of the food just gets burned rather than stored as fat. So yes Puertasaurus was very massive, easily a hundred tons or more - but the shape of its mass did not exceed its own limits of reasonable movement. True, it was an ocean liner with legs, but still, it had no trouble moving those legs. More like a sumo wrestler than a Manuel Uribe.

Anonymous said...

Thanks for you response. I'm new at posting here and my e-mail was not recognized so I went in as Anonymous. My name is Tom Pearcy and I have an art background starting at Ohio State in the early 1970,s. I did not do the artwork for a living however.
By modulations I meant the use of dark and light patterns to suggest depth or Chiriascuro-I think is how that is spelled.
This is what it seems you are doing on your updated Puertasaurus cervical drawing to convey more of its character.
Do you know of any attempt to find more of the Puertasaurus skeleton?
I've been following your recent comments on the Futalognkosaurus findings and it will neat to see ow you interpret it.
Thanks for your clarification of what you are trying to do as an artist- it was helpful as well as amusing.

Nima said...

O.... thanks Tom. Yes the cervical has a lot more depth now. It was tricky because a good shaded reconstruction of this thing was virtually non-existent, as far as I know mine is the first one. I don't know if anyone is searching for more of Puertasaurus, but I wish that Fernando Novas and his team would keep looking (I don't know if they are). It would be a shame to have Puertasaurus become a one-paper wonder, and the two caudals haven't even been published yet. This thing deserves as much attention as Argentinosaurus, maybe more. It's bigger, and a heck of a lot weirder.

My main aim with this piece was to show the extreme volume of Puertasaurus. This was a very wide dinosaur, in fact most titanosaurs were wide, but many artists forget to depict them this way. Titanosaurs were really a very diverse and unique group of sauropods, each had its own odd features, but I'd say easily 80% of the illustrators out there don't pay attention to this and just draw them all as diplodocids with a few armor studs slapped on the torso. That's not science, it's a joke. Of course there are still many artists who DO get it, and I applaud them for their efforts. But even then, many of them forget the extreme width of these titanosaurs.

There's probably more material at the Puertasaurus site, but I don't know if they've found anything else yet. It seems strange that they found the caudals but no lower dorsals. As for Futalognkosaurus.... have you been looking at my debates on Deviantart? And if you don't mind me asking, what profession did you go into instead of art?

Anonymous said...

Nima, I think you have acheived your aim and have obviously spent a lot of time and thinking on it and the results are fascinating.
I have followed your debates on Deviant Art unless something more was posted in the past few weeks. I will try looking again. It will be nice to see the new paper with more measurements I have heard about from you and others on Futalognkosaurus.
My main interest other than making artwork was in teaching which would have been a natural thing for me but college and university teaching took a real nose dive around 1973 or so and to the best of my knowledge has never recovered-I hope it may someday.
So I went into Librarianship many years latter and enjoyed its educational side. I started as an accademic at Ohio State but went into Public library work where there were more jobs.
The art still holds my fascination though and I have been getting back into it. I do not do illustration but Luminist style work not too unlike Ryder and Blakelock.
I have studied visual perception in the arts and have learned to appreciate how the visual cues influence perception-things like overlay, brightness,size and others. This helps in constructive criticism.
Anyway be sure that many of us are following your work with real interest. i appreciate the intuition you bring along with your strong desire for scientific discipline. Tom Pearcy

Zach Armstrong said...

Well I must say I am impressed by all the research you did that went into your reconstruction, Nima. Obviously, I have a few misgivings, but you already know what they are.

It is much more helpful to know what the reconstructed size of the vertebrae is in that picture. Of course, that will change the volume estimate that I had done previously based off of it--probably increasing it dramatically. My original estimate based off of it using the measurements from the paper was over 130 tonnes (metric tons).

I am actually probably okay with how wide you restored the torso now, after seeing a multiview skeletal restoration of Uberabatitan (I was curious after you mentioned referring to Uberabatitan--it is apparently known from a lot more material than I previously realized). I would still change the width of the hips, as the ilia flare out to match or exceed the maximum torso width, and narrow the shoulder area slightly. I would also lengthen the tail, maybe 1.5 times as long as you have it restored in accord with complete tails of unpublished lognkosaur material that I am aware of (but of course you wouldn't have known about it, so I digress). I am a little unsure of restoring the "D2" (I'm inclined to say it is a D3, for various reasons) to 1.9 meters wide, as that seems unnecessairly speculative; maybe 1.75 meters at the max.

But these are nitpicks of an otherwise very good drawing. All-in-all a very high quality, dramatic restoration. I am looking forward to the next installment in the series.

Nima said...

Thanks for the info, Tom. I've seen Blakelock's stuff, it's very good (though when it comes to "Illumination" painters I'm more of a Bierstadt fan myself, but hey, tastes vary... ) By the way, who exactly is "many of us"? I'm curious, do I have a lot more fans than I realized?!? By all means invite them to comment, I'd love to hear from them :)

And thanks for the compliments Zach, this was a very challenging but fun restoration to do. Mainly the best part was that the whole concept was completely original, i.e. I didn't use any other artist's work for inspiration and went straight off the bones, and getting the perspective right was pretty tricky as well, the neck and torso shape on this beast is downright crazy. As for Lognkosaur tails, I don't think they were quite so long. But in any case, for Puertasaurus the tail length is over 45 feet, so it's not exactly short either. With Lognkosaurs, there's still a good possibility that not all genera had the same tail proportions. Titanosaurs in general have a wide diversity of proportions and body shapes, and from what I can tell of Malawisaurus, they probably followed a basic body pattern roughly similar to brachiosaurs, with a reduced tail (though perhaps not AS reduced).

The next installment will be coming soon. And it will have a more impressive tail, I can promise you that :)

Anonymous said...

My feeling is that that there must be many like myself, armchair enthusiasts, who enjoy searching and finding facts, images and opinions about "The Wonders of life on Earth" both now or at any other time.
So, I don't belong to any group or club but an educated guess is that there are many people searching for information who have found your drawings and writings and found them as interesting as I have.
I have been visiting the Sauropod Vertabrae site and that is where your work first came to my attention. As time goes on and you keep on posting others will pick up on your contributions to the field and keep coming back.
As I get older it becomes apparent how important contacts are for jobs, shows and regular stimulating conversation among other things.
Anyhow as a woman who worked at a lunch counter once told me about artists .."theres always room for a good one" This talent takes time to develop.
You know how hard it is just to get a "balance" in a composition. This is a difficulty every artist has. Sometimes the use of a simple overlay-say a few ferns or rocks overlaying overlapping a foot or tail or will bring out the illusion of space more clearly when a picture looks "flat" I noticed this once on a well known paleo artists drwing of a Tyranosaurus.
Thank you and your fellow enthusiasts for filling in some of the blanks for us in your work .

Brad said...

Your restoration of Puertasaurus in anterior view looks very similar to Gregory Paul's Futalognkosaurus, but wider. Perhaps a sign you're on the right track, if you came up with it independently. :)

Nima said...
This comment has been removed by the author.
Nima said...

I did come up with my Puertasaurus restoration independently, thanks! But waaaaaaait just a second - Gregory Paul has done a Futalognkosaurus diagram? NOOOOOOOOOOO! He beat me to that one!

I have a Futa in the works myself, it's a skeletal so it's taken a while to do. The only Gregory Paul skeletals had available for reference (and even then, just for tips on how much detail to include) were Giraffatitan and Euhelopus. I don't have any copies of his titanosaurs, in fact I wasn't aware his new book was out yet!

The width of the rib cage is the result of careful scaling and measurements, all scaled by hand with a ruler, and extrapolation from more complete titanosaurs, as well as the extreme width of the dorsal vertebra with its huge buttressed diapophyses. These indicate a very wide rib cage, likely wider than it was deep. I did not have ANY reliable top or front views of titanosaurs to work from, so this was all done from scratch.

Brad said...

Well, there isn't a skeletal diagram of Futalognkosaurus by Gregory Paul (at least as far as I'm aware). I'm talking about his drawing of it as a living animal. It's in the 6th supplement to Donald Glut's DINOSAURS: THE ENCYCLOPEDIA.

Steve O'C said...

It's an awsome drawing. I still think you have the scale bar and human way too small. By aprox 20%.

A few years back I drew a quick Puertasaurus recon for the same reason you did. All the restorations on the Net had a short neck, and the only known neck vert is estimated at about a meter long!

I got a neck length of about 9-10 meters and that was asuming only 13 cervicals....

Regarding your giganotosaurus: Because of the scale bar issue, it comes out at about 15.5m long. If you scale GSP's giganotosaurus to have a femur the length of the holotype, it comes out at aprox 12.5m...If you assume the second specimen (the ~ 8% larger jaw fragment) is similary proportioned then it comes out at about 13.5m long.

Nima said...

Thanks for the compliment!

It's odd that you got those measurements off of my drawing, because with the scale bar the way it is now, I only got a 14m (~46 ft.) length for the Giganotosaurus, which is a perfectly reasonable upper limit for the larger jaw fragment specimen (I did label that image as the maximum size for Giganotosaurus BTW).

As a side note, I didn't trace GSP's skeletal of Giganotosaurus, I actually reconstructed mine from scratch and published measurements. The margin of error on my scale bar and the Mr. Sandow figure is not more than 10% max, I scaled it several times to be sure. 20% is a bit excessive.

I did draw the Puertasaurus bones slightly larger to account for erosion, crushing and missing fragments, but the difference is not as major as some have assumed. A minor quibble at most, it's bound to happen when you're dealing with such a large and incomplete specimen. As with most of what I have planned for FORGOTTEN GIANTS, this animal has to be restored with a good bit of educated guesswork, so there is room for interpretation, and in fact I'm open to revising anything if new material turns up or I discover something about a titanosaur that I hadn't known before. I definitely see this first installment of FORGOTTEN GIANTS as a major leap forward from the few short-necked cartoonish restorations of Puertasaurus that existed previously, but who knows, someone might put my own restoration to shame within the year.

BTW, I'd like to see your recon of Puertasaurus, please post a link!

Steve O'C said...

I didn’t read the part where you discuss modifying the vertebra, my bad.

I just checked again and the Gig came out about nearly 15.5m. I’m using Photoshop CS 3’s measure tools.


My recon was/is rubbish.

It's old and the anatomy is all over the place. It was done really quickly just to get an 'idea' of the neck length. A lot of it was ‘’eyeballed’’, I didn’t spend ages cross comparing titanosaur necks etc. I didn’t properly consider the width of the vertebra when drawing the legs and shoulder blade etc..

In some respects it’s more on the conservative side, my intention was to get a ‘minimum’ size.

It includes Carpenters Argentinosaurus skeletal, scaled to have a tibia length of 1.55m. (I didn’t trust the scale bar in the paper and that was the only measurement I knew.) That was used to for the length of the body. I’m not sure how accurate Carpenters Argentinosaurus is however.

Anyway, here it is.

http://i208.photobucket.com/albums/bb186/Steveoc_86/Palaeo/Peurtosaurusu_rough_2_WEB.jpg

Nima said...

That's not so bad.... it's just way too narrow-bodied and generic-looking to be Puertasaurus (the rib cage is just way too thin for that huge wide dorsal vertebra!). The body looks like a basal andesaurid, while the head is saltasaurid. If you switch it out for a more boxy, crested head, it would actually make a very decent Andesaurus or Chubutisaurus.

Ken Carpenter's skeletal is just flat-out wrong in nearly all its proportions (the scaled human figure seems okay though). It's far too small at the front to be a big andesaurid like Argentinosaurus - the neck, front torso, arms are all tiny (plus he oversimplifies the shapes of the vertebrae and their line of articulation is too straight to be realistic). Even if you took the original silhouette and called it Saltasaurus, it still looks too rear-heavy to be Saltasaurus! It's more like a weird cross between Saltasaurus and Brachytrachelopan... nevertheless, the actual paper that included this illustration was EXTREMELY well-written.

Steve O'C said...

Is there actually any known correlation between dorsal width and ribcage width?

For example, If you scale GSP's Giraffatitan to have a second dorsal measuring ~1.70m then you get a ribcage width of about 3.6m. If you scale his Camarasaurus you get a ribcage about 4.6m. (I'm not imlpying that Giraffatitan or Camarasaurus are a good models for Puertasaurus. They are the only mutli view diagrams I have available.)

Nima said...

There is no actual correlation between dorsal width and ribcage width - the typical ratio varies among different families of sauropods, and within titanosauria itself it seems to fluctuate like crazy.

However, the full proportions of a vertebra (not just the raw width) can tell us a lot about how wide the rib cage probably was.

Dorsal width alone is not even the issue - rather, width-height ratio and diapophysis size are the really big clues here. Look at the diagram with the different vertebrae drawn in anterior view. Amphicoelias fragillimus (in Carpenter's version of the dorsal) likely had a backbone almost as wide as that of Puertasaurus, but its dinky little diapophyses indicate it still had a much narrower ribcage. Meanwhile, the Amphicoelias altus dorsal is just as tall as the Puertasaurus dorsal but barely 1/3 as wide! And its diapophyses are something like 1/5 as wide as those of Puertasaurus. Once again, a skinny ribcage.

Now I know Camarasaurus and Giraffatitan have wider diapophyses (and wider vertebrae overall) than diplodocids like Amphicoelias, but they are still proportionally nowhere near as wide as those of Puertasaurus. If you scaled a Giraffatitan vert to the same height as the Puertasaurus one, you'd still have a much narrower vertebra and smaller diapophyses. Indeed Jurassic macronarians are not good models for Puertasaurus in that particular regard - and I myself wish there were multiview titanosaur skeletals more easily available online.

The Puertasaurus vert has proportionally the BIGGEST diapophyses and greatest width-height ratio of any described sauropod. Now I doubt it had such gargantuan "backbone wings" just to carry a measly camarasaur-like ribcage, or even a somewhat wider brachiosaur one.

Also, the laminae under the diapophyses are huge and deep, those things are so over-buttressed they practically merge with the centrum seamlessly. This only makes sense if the diapophyses were supporting an incredibly massive load that ordinary, un-buttressed processes could not easily handle, and sauropods with slim rib-cages lack this feature entirely. 2/3 of the vert's width is diapophyses! I have never seen a ratio even near that in any camarasaur or brachiosaur, or in anything other than titanosaurs (and even then, the more basal types still don't have the diapophyses so wide).

Interestingly, the related Futalognkosaurus has very similar wide dorsals and huge diapophyses too - and the type specimen includes the ribs. If Calvo et. al. publish a more detailed paper on it, especially regarding the rib heads, that would be a huge clue as to whether the Lognkosaur clan had unusually wide rib cages or not. For the present, based on all the data available so far, I accept that they did.

Anonymous said...

what is your next forgotten giants species?

Anonymous said...

And when is it coming out?

Anonymous said...

Were there any armored brachiosaurs?

Anonymous said...

Were there any armored brachiosaurs?

Anonymous said...

Hello, my name is Piotr and I really like your artwork. You should try to do a study of at least one species of every dinosaur family discovered so far like you did with Puertasaurus. And why can I only find your Argyrosaurus in the sauropods gallery on ArtEvolved?

Erick said...

I was looking for information on FORGOTTEN GIANTS, #1: Puertasaurus and before ending in your blog I watched like 10 sites about viagra online, the web is full with that topic. But anyways the info on your site help me very much, thanks for the post and have a nice day.

ther1 said...

Nima,

I am doing a report on the use of library science to reconstruct dinosaur anatomy, and would like to include your Puertasaurus drawings it. I will give you proper credit if you allow me to use them.

Thank you,
Sara

Greg said...

Hi Nima,
Please correct your data on the find.
Pablo Puerta is not a farmer, he's a technician in paleontology at the Egidio Feruglio Museum in Trelew, Argentina. Please see the link to the news of the find: http://old.clarin.com/diario/2006/07/22/sociedad/s-05301.htm (you can use Google translate to read it).

(I am a childhood friend of Pablo Puerta's sister, and she was telling me about his find. I then googled it and stumbled upon your page.)

Nicole Galvanston Nedafarioa said...

Hi, Nima.

I was wondering if you could do a forgotten giants page on Amphicoecilas, if you already did, that is.. Amphicoecilas was a diplodocid and Titanosaurid, -cousin of titanosaurids- right? I read a lot of books about dinosaurs and most of them are outdated, Wikipedia's "authentic" information seems wrong and outdated. Puertasaurus and Amphicoecilas were ornithschians (i forgot the proper spelling), right? I can't find any confirmed information online, but your page helps a lot. I had no idea Amphicoecilas was a diplodocid, I thought it was a huge titanosaur! I tried to draw them both on scale, but Amphicoecilas ran through the whole paper and Puertasaurus was too fat and ended up with his sides touching the edges of the paper. My drawing was trashed later on T_T. I also have this book, called Dinosaur Record Breakers, and it shows Amphicoecilas -and the other sauropods- with spikes running down its back, it said diplodocus had a whip of a tail,

It also said Carcharodontosaurus was only bigger than a Mapusaurus but dwarfed by the others -Spinosaurus Aegyptiacus, Tyrannosaurus Rex, Giganotosaurus Carolonii.- All this information confuses me a lot. Didn't herbivores normally outnumber carnivores by nearly 10 to 1? Why are they so rare?

Sincerely, Nicole

Giga Dino said...
This comment has been removed by the author.
scott davidson said...

What an interesting blog, introduced by a thought-provoking photo. The unusual wall painting of the dwellings is also a strangely modern interpretation. Something like this hieroglyphic view of a park by Swiss painter Paul Klee, http://EN.WahooArt.com/A55A04/w.nsf/OPRA/BRUE-8LT475.
The image can be seen at wahooart.com who can supply you with a canvas print of it.

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