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yty2000 In reply to Thalassophoneus [2019-08-29 03:53:35 +0000 UTC]

Probably due to the speculated position of the preserved cervical and placement of the shoulder girdle, the neck length would be different in various skeletal reconstructions.

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yty2000 In reply to Steveoc86 [2017-09-25 06:14:25 +0000 UTC]

Thank you very much, I enjoy your work as well.

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yty2000 In reply to Paleo-King [2017-01-09 04:12:37 +0000 UTC]

Its torso is probably not as wide as Futalognkosaurus and some other titanosaurs, but it certainly has some very robust limbs.

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Paleo-King In reply to yty2000 [2017-01-09 06:12:35 +0000 UTC]

Well robust for a sauropod in general... the lower limbs are slim for a lognkosaur. Nevertheless this animals was a lot bulkier than GSP restores it. He doens't even account for crushing and erosion in the limb bones so the legs look ridiculously thin, even with minimal flesh they should be thicker than how he does them.

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yty2000 In reply to Paleo-King [2017-01-09 16:51:43 +0000 UTC]

I was not aware of GSP's reconstruction. In the Notocolossus paper, they presented a tree where Longkosaurs are within Lithostrotia and somehow closely related to Tapuiasaurus, which is a pretty derived Titanosaur I thought. Thus the usage of Tapuiasaurus skull here. I am not informed enough to make my own conclusions, guess I will have to re-read some of these papers again.

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Paleo-King In reply to yty2000 [2017-01-10 10:53:46 +0000 UTC]

I have read that paper. The data set is not bad but still the fact is that there is not much overlap between Notocolossus and Tapuiasaurus in terms of extant material. We don't have a skull for Notocolossus. Or cervicals.

It is also important to remember that different methods with the same data can result in different trees. Using bootstrap, bayesian grouptings etc. it's all about how you tell the computer program to discriminate between basal, derived, and convergent characters.

I have seen other papers with big data sets reach a different arrangement of the titanosaur phylogeny. So it's a toss-up unless they combine all the characters in all the major papers to get a better picture.

Lithostrotia is defined typically with lognkosaurs in it. However I consider them to be just outside of it, based on the armor types being different, and also different pattern of caudal morphology and also other key parts like femurs and dorsal vertebrae. The group "Lognkosauria + Lithostrotia" should in my view be renamed as Osteodermata, with true lithostrotia being the clade containing Antarctosauridae, Trigonosauridae, Saltasauridae and Nemegtosauridae. I would have placed Tapuiasaurus up with the nemegtosaurs, not with lognkosaurs, but again I understand how this could happen given that there are so few parts for Tapuiasaurus known besides the skull, and most of them are fragmentary or eroded. It's possible that either some characters were coded wrong or perhaps the fact that there were so few characters to work with for Tapuiasaurus artificially biased the result... if more remains for it were known, we may have seen additional characters that were different from lognkosaurs and that would have totally changed its position in the family tree.

Here is the problem with taking the family tree at face value, even if all the characters are entered correctly:

From what I can see of the traits of Tapuiasaurus, aside from the skull, the other remains are eroded so badly that they only preserve the most basal traits, which ALL osteodermatans have in common. So in the absence of well-preserved nemegtosaur traits, the program would automatically place them at the basal end of "Lithostrotia" or rather Osteodermata, with the lognkosaurs, but what it's REALLY saying is that there isn't any data on this animal's unique derived traits so the program places it in a basal position because the data only contains basal traits common to all Osteodermatans. It doesn't necessarily mean it was a lognkosaur, only that it shared some basal defining traits with lognkosaurs that are NOT found in animals more basal than the lognkosaurs.

So that is why I look at the actual data matrix, because you will find that a LOT of characters are unknown for Tapuiasaurus simply because it's so incomplete. Like it or not, incomplete or fragmentary specimens tend to preserve mainly the most obvious, basal, common traits of the animal, rarely the smaller and more recent derived traits, and this can bias the comparison even if everything is coded 100% correctly. Which is why we LOVE complete or near-complete sauropods. If only they could all be as complete as Dreadnoughtus or more complete.

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yty2000 In reply to Paleo-King [2017-01-10 15:44:56 +0000 UTC]

Thanks for the detailed explanation. Maybe I should change the skull to look like something between a Sarmientosaurus and a Saltasaurid. It was mentioned that Dreadnoughtus shares some characters with Aeolosaurines though, which gives me the idea that it might be some kind of basal Lithostrotian.

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Paleo-King In reply to yty2000 [2017-01-10 20:42:17 +0000 UTC]

I heard the aeolosaurine rumors too, long before it was described. But I've seen pictures of every aeolosaurine and none of them look much like Dreadnoughtus so if it shares any traits with them they are either convergences or most likely found in all osteodermata.

Again omission is just as big a problem as commission. Some papers unfortunately do this. For example I can say "both lognkosaurs and aeolosaurines lack hyposphenes". To the average joe reading the paper, that "must" mean they are very closely related. But it just isn't so. Nearly ALL titanosaurs except Andesaurus, Argentinosaurus, and Epachthosaurus lack them. But the act of NOT mentioning that creates an artificial implication that there is an unusually close relationship between lognkosaurs and aeolosaurs, when there is not. This is how sources can mislead without outright lying - much like the corporate media does. Sometimes though, it's not even intentional, the author(s) may simply be putting in that detail because of their own personal experience with working on aeolosaurs and not much else.

By the current definition of lithostrotia, lognkosauria is at its basal end. However it has enough anatomical differences with nearly every other group commonly placed in lithostrotia that I would put it outside the group and basically rename lithostrotia as osteodermata, with true lithostrotia being everything more derived than lognkosaurs and argyrosaurs. Also by definition lognkosaurs do not have flat or keeled armor plates, they have long spike-osteoderms. They also lack small nodules between the plates. So they are not "lithostrotos" in a literal sense either, their armor is very different from true lithostrotian ("paved with stones") armor.

Sarmientosaurus is a bit odd because it is a non-titanosaur, but its nasal arch has been crushed to it looks smaller than it was.  It is probably a chubutisaur based on the big teeth and overall basal brachiosaur-like features of the snout (actually the most similar set of teeth comes from the unusual chubutisaur Ligabuesaurus), but nevertheless did have a small nose for a non-titanosaur macronarian. Euhelopus and Paluxysaurus had larger nasal arches.

The problem is, it's a lot more basal than Andesaurus. So not a true titanosaur. However Malawisaurus, the closest relative of lognkosauria, has a big nasal arch. So it seems large nasal arches were common even in titanosaurs at least up to lognkosauria. I doubt lognkosaurs had a nemegtosaur-like skull or even a Sarmientosaurus-like skull. Sarmientosaurus is an oddball in any case, it was a small-nosed somphospondylian among several big-nosed ones. More the exception than the rule.

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yty2000 In reply to Paleo-King [2017-01-10 23:01:06 +0000 UTC]

I am not sure that Argentinosaurus has a true hypantrum-hyposphene either. It's true that the prezygapophyseal laminae aren't fused in the middle, but the "hyposphene" that would fit into the gap would block off the neural canal. Mike Taylor wrote about it on SVPOW. Argentinosaurus might be something between some of the most basal Titanosaurs like Andesaurus and the more derived ones.
Chubutisaurs and Sarmientosaurus aren't titanosaurs? I'm even more confused now.

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Paleo-King In reply to yty2000 [2017-01-11 21:50:54 +0000 UTC]

I read that too.. which is why I think Argentinosaurus and Epachthosaurus may be basal but definitely LESS basal than Andesaurus. They are losing the hyposphene but still have a small one. They can be the more basal transitional forms along to path to Malawisaurus and eventually to lognkosauria.

Chubutisaurids have never been titanosaurs. They are basically a couple steps more derived than brachiosaurs. Paluxysaurus and Sauroposeidon belong in this group after all. They look like brachiosaurs in many ways. Between chubutisaurs and titanosaurs there are a few more nodes. You have to get through huanghetitanids, euhelopodids, and acrofornicans (which look like more advanced euhelopodids) before you get to true titanosaurs.

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yty2000 In reply to Paleo-King [2017-01-12 21:08:16 +0000 UTC]

I agree. The "hypantrum-hyposphene" structure in both Argentinosaurus and Epachthosaurus share some similarities in the articulation. Epachthosaurus seems to have transverse processes tilted more dorsal laterally.

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yty2000 In reply to Paleop [2017-01-09 03:16:13 +0000 UTC]

Thank you. I wish someone is working on an osteology paper of Futalognkosaurus; I wanna draw it as well.

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Paleop In reply to yty2000 [2017-01-09 14:25:20 +0000 UTC]

I asked someone about the osteology paper and it's still sadly unreleased. 

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Paleo-King In reply to yty2000 [2017-01-09 03:51:05 +0000 UTC]

Next best thing is my multiview... which I am editing AGAIN lol.

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yty2000 In reply to Paleo-King [2017-01-09 04:06:25 +0000 UTC]

Where did you obtain the images and measurements of undescribed material?

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Paleo-King In reply to yty2000 [2017-01-09 06:10:23 +0000 UTC]

There isn't much undescribed material - only 2 juvenile referred specimens. The holotype is described, I used the published photos as well as unpublished photos. There are photos of the juvenile material too, such as femur and a couple extra caudals. It's not exact measurements but a LOT of cross-scaling with photos from different angles. Like YEARS of hunting down photos and estimating sizes.

There are a lot of photos of the bones online, it's just a matter of cross-scaling and getting different angles to approximate the size and shape. The gaps which none of the 3 specimens cover, were filled with Mendozasaurus material, the new revision I'm working on will use some Dreadnoughtus material to fill in the gaps because Mendozasaurus appears to be a more distant relative.

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yty2000 In reply to Paleo-King [2017-01-09 16:14:50 +0000 UTC]

I mean the referred limb bones. Also are you sure those are from juveniles? The femur is 198cm long I think, seems pretty appropriate for a 25-26m long animal like the holotype specimen.
I find photos quite unreliable when there's no corresponding measurements. Most of the presacrals of Futa have no published measurements.
In the case of Dreadnoughtus, the 3D meshes made reconstruction so much easier.

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Paleo-King In reply to yty2000 [2017-01-10 11:00:10 +0000 UTC]

Well now you know my frustration with Futa and why there have been so many versions of my skeletal as I find out better photos and more data.

Yes, Dreadnoughtus was handled MUCH better. It's not as if the same 3D scan couldn't be done with Futa, it's not THAT much bigger.

Where did you get that femur measurement? I have seen only two femurs that could possibly be Futa specimens, and both are rather small based on the people and objects in the pics. The holotype didn't include a femur in the paper and I haven't seen such a large femur in any photos.

I have seen some pics of large titanosaur femurs that may be from Lago Barreales site but they were not properly labeled and may be from a different site with merely the same color soil, no telling if they are Futa as the angles were horrible.

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bLAZZE92 In reply to Paleo-King [2017-01-11 07:41:49 +0000 UTC]

2 and a half years ago I informed you of a humerus and femur of similar measurements being attributed to the holotype in the supplementary material of Benson et al. (2014), you said back then that they must belong to juvenile specimens.


btw, your skeletal is still 14m atlas to sacrum, much bigger than what Calvo says it is (11.9m).

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Paleo-King In reply to bLAZZE92 [2017-01-12 12:25:12 +0000 UTC]

Calvo's measurements are fishy. I work off of what I can cross-scale with photos that have scale rulers and other fixed references in them. The reference bones I have cross-scaled, I am pretty confident are the right size. And that is how I got the measurements. Also ROM casted some of the bones (but copied others from Alamosaurus) and overall got a similar size.

Honestly I suspect Calvo didn't even measure it himself but relied on other people under him who probably left out a few bones or something. I hear he's a very busy guy. I mean he left this humerus and femur out of the description paper and still hasn't described the juveniles or the other 2 titanosaur species supposedly found at Lago Barreales. Either he's super busy or super sloppy. Not that I would know which... given that he hasn't described another titanosaur since 1991, I thought he would be all over this. But we STILL have a Futalognkosaurus-sized pile of unanswered questions. Calvo "says" really means he "said" something several years ago. I've never met him at SVP (again I hear he's busy and I don't blame him for not making the long trips) and I've never seen interviews or even a picture of him. He's notoriously hard to pin down. Hardly anyone at SVP knew anything about his strange measurements either. Or for that matter who took some of the photos floating around on the net which are FAR more informative than any of the published ones (some of these have been taken down so good thing I saved them).

When what I see in publications contradicts what photos with scale rulers (not mere scale bars) show to be true, I have reason to question even their published measurements. I've been fed bad information far too many times before to simply ignore unofficial photos with scale references.

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bLAZZE92 In reply to Paleo-King [2017-01-13 17:56:57 +0000 UTC]

You know that with bones this big perspective distortion can compromise even rulers or other objects on or next to the bone. But it's ok, you stand by your estimates, I have done the same too so I understand.

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Paleo-King In reply to bLAZZE92 [2017-01-13 21:52:59 +0000 UTC]

Yes I agree it is difficult at the best of times because not all the photos are from a good angle.

Ideally I would like Calvo and co. to actually take straight, focused COLOR photos in high resolution, with those cheap SVP scale rulers for comparison.

This is SO easy, anyone with a smartphone can do it these days. Why is it so hard for a professor with assistants and grad students to have somebody do this for him?

It is truly sad that the best and most data-rich photos of many titanosaur fossils are NOT the published description pics, but casual "pose with the giant" photos taken by museum visitors from abroad. This is the case with Futa, with Traukutitan, with many others.

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yty2000 In reply to Paleo-King [2017-01-27 04:22:51 +0000 UTC]

It's actually not that easy to take good photos with smart phones. The lenses have a wide angle of view and usually causes plenty of perspective distortion.
You can actually follow Calvo on twitter:
twitter.com/JorgeOCalvo/media

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Paleo-King In reply to yty2000 [2017-03-28 23:26:33 +0000 UTC]

Thanks this is great! Lots of cool stuff I didn't know about, especially the footprints at Lago Barreales. It's rare to find bones and footprints in the same site.

I can see how it might be difficult to take good pics with phones on really big bones in the small metal hangars, however at a distance it should be much easier now with the better phones. Even with a bit of perspective distortion, it would be much better if we had good lateral pics of the sacrum and dorsals, as well as a good front view of the humerus, radius, ulna and metacarpals (there are at least two of them in the video here: www.proyectodino.com/el-proyec… ). Also most of the anterior dorsals look crushed but again some pics would be useful here. Any one of the students at the site - there were several in the old pics on his twitter and a lot more in the new ones - could have set up the scale ruler and snapped a few pics if Calvo was too busy. Some probably did, which is where we get some of the online pics from, but I'm sure they could have snapped a few more from lateral angles. I get the impression that as much of a badass as Calvo is, he is looking more at the big picture - mainly in charge of organizing the digs, the PR and the whole Proyecto Dino center, and other people handled the photos, the measurements (*cringe*) and the fossil prep.

But even with an old school SLR it could have been done. Calvo's smartphone pics may be at bad angles but the resolution is much better than anything that made it into his papers. IMO just a couple of more standard angles of one or two elements (forearm and dorsals for example), and some scale rulers, would make a world of difference.

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yty2000 In reply to Paleo-King [2017-01-10 15:30:28 +0000 UTC]

It's in the supplementary information in the Notocolossus paper:
www.nature.com/article-assets/…
page 51. This humerus is listed at 156cm; femur is 198cm.


The source reference is:

Calvo, J. O. New fossil remains of Futalognkosaurus dukei (Sauropoda, Titanosauria) from the Late Cretaceous of Neuquén, Argentina in

4th International Palaeontological Congress, The History of Life: A View from the Southern Hemisphere abstract volume (ed Cerdeño, E.) 325 (International Palaeontological Association, 2014).

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Paleo-King In reply to yty2000 [2017-01-10 20:43:16 +0000 UTC]

WOW. I wonder why this humerus and femur were left out of the Futa holotype by Calvo. Of all places we see them included, it's a paper about a totally different species.

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yty2000 In reply to ZEGH8578 [2017-01-08 23:34:17 +0000 UTC]

thanks!

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