Largest sauropods

[Fragillimus335]

Jun 29, 2013 2:17:56 GMT 5 theropod said:

Most of the Broome tracks also seem to be pretty round (Thulborn, 2009), but Diplodocids were most likely not present in that habitat. On the other hand pes prints from Lourhinha, possibly made by Dinheirosaurus are not round at all (Mateus & Milan, 2010).

I'm taking a strong interest in ichnology at the moment

Like I said, wild ass guess!

[coherentsheaf]

Scott Hartman regardig the paper Fragilimus cited:

"It's possible that the paper is accurate for the specimen they calculate it on, though they have the metatarsals too elevated in my opinion (and the opinion of most of the people who are doing biomechanics) which of course impacts the fore-to-aft length of the restored pes. But either way we shouldn't expect a single strict foot-length to hip height ratio."

For our purposes this means: Caution, this way of estimating the Broome titanosaur may have serious downfalls - foot length is at best a very rough guide to size.

[theropod]

I agree. I was never a fan of generalized foot-lenght to hip height formulas. Animals vary in their proportions and one formula for all titanosaurs can hardly be reliable.

Foot lenght should be most closely linked to body weight actually.

[Grey]

MIKE TAYLOR - I have a recurring nightmare of being in a pub quiz where one of the questions is ‘what was the biggest dinosaur?’ All my team-mates look to me for the answer, but I'm paralysed - what answer do the quiz masters want?

The heaviest dinosaur known from reasonable remains is probably Argentinosaurus at about 70 tonnes and 30 metres. But the lighter Supersaurus was probably longer, at maybe 35 metres. Problem is, these are known only from partial skeletons. Among dinosaurs known from complete skeletons, the heaviest is Giraffatitan, but it's not quite as long as the lighter Diplodocus.

And yet there are tantalising hints of bigger dinosaurs. Much bigger dinosaurs. These are “the ones that got away”.

The longest dinosaur that we have evidence for was found 135 years ago. It was named by Edward Drinker Cope as Amphicoelias fragillimus in a brief note that included a drawing of the only bone (below, next to a Diplodocus vertebra) that was ever found from it: the top half of a vertebra from the back.

That doesn't seem like much to go on, but features of the vertebra indicate that it was from a sauropod in the same family as Diplodocus, and the size of the preserved part suggests it was about 1.9 times as big. If that's right, it would have come out at about 50 metres and 80 tonnes. But other published estimates have gone as high as 58 metres and 122 tonnes. It's just impossible to be sure when so much guesswork is needed even to figure out what the vertebra would have been like when complete.

The tragedy of Amphicoelias fragillimus is that the one bone we had is gone - destroyed or lost. Cope's drawing was made out in the western badlands of the United States before the vertebra was shipped cross-country to the American Museum of Natural History.

It seems it never arrived. It might have been misrouted or stolen, but most likely it just crumbled into dust during the journey. I like to imagine it crated up and hidden away in a vast warehouse, like at the end of Raiders of the Lost Ark, waiting to be rediscovered. But there is another sauropod, discovered much more recently in India, that was probably even heavier: Bruhathkayosaurus.

The most important specimen was a tibia (shin bone) which it is claimed was two metres long. This compares with 112 cm for the tibia of Giraffatitan. If Bruhathkayosaurus was similarly proportioned it would have been 78% longer (about 43 metres) and 5.7 times heavier (perhaps 170 tonnes). But since Bruhathkayosaurus was probably a titanosaur, and so more heavily built than Giraffatitan, it could have topped 200 tonnes.

This is truly colossal – heavier than all but the biggest blue whales. The idea of an animal that size moving around on land is shocking, even to palaeontologists. Can it really be true? We may never know for sure because (stop me if you've heard this one) the one bone we had is gone. It was never moved inside a museum – perhaps understandable given its size – and got washed away in a flood. It really is a crying shame that all we have left of both of the biggest-ever dinosaurs is drawings.

At least the Amphicoelias drawing is a good one. Sad to say, the only published drawing of the Bruhathkayosaurus tibia is terrible – a mere scribbled outline that really tells us nothing about it. Its identity as a titanosaur tibia rests on second-hand information that can now never be verified. It might have been the distorted femur of a merely Giraffatitan-sized sauropod. Not all palaeontologists are even convinced that it was a bone at all, rather than a fossilised tree-trunk.

So how big did dinosaurs get? The honest answer is that we don't really know. My intuition, based mostly on Cope's pretty good Amphicoelias description, is that at some point, someone is going to find good remains of a sauropod that uncontroversially topped 100 tonnes, maybe much more. But who knows how long we'll have to wait?

- Dr. Mike Taylor is a computer programmer in his day-job, and a Research Associate at the University of Bristol. He has the luxury of working almost exclusively on sauropods, the most impressive and inspiring of all dinosaurs.

www.walkingwithdinosaurs.com/news/editorial/biggest-dinosaurs-amphicoelias-bruhathkayosaurus/1/

[theropod]

^He seems to exclude ichnotaxa here. And yet, it is obvious what he implies

[Grey]

The biggest of the big



I don't know if that grabs your attention, but sorting out the size of giant sauropods sure grabs mine. Let's take a more detailed look at some of the critters in this image:

First off, I need to admit that this is not all inclusive. The legendary Amphicoelias fragillimus will never be included (unless more material is found). I have not sufficiently nailed down the scaling of Argentinosaurus yet to include it, but early scaling makes it look like it's the same size or slightly smaller than Puertasaurus (which I did include).

Note that most of these animals are only known from a single specimen (and often quite incomplete skeletons at that), which means that we don't really know what the size range of animals was in a living population. So keep in mind that while we can compare individual specimens, we can't say with any certainty that the biggest skeleton really came from the biggest sauropod species.

Here are some other quick hits:

1) For personal reasons I love me some Supersaurus. I've scaled the reconstruction to the size of the WDC specimen (32m), though the type specimen may have reached 34m in length. Either way it's the longest sauropod we can reasonably restore, though it certainly was not the heaviest (diplodocids tend to be fairly slab-sided compared to titanosaurs).

2) The large NMMNH Diplodocus specimen (originally named Seismosaurus) is also very long (~30m) but probably even lighter in mass.

3) Diplodocids may rule the roost in length, but macronarians seems to (mostly) crush them in terms of mass. Puertasaurus is currently my reigning champion; filling in the (extensive) missing elements with other lognkosaur relatives leads to a 27 meter long animal that is clearly the heaviest of the group (I'll speculate maybe in the 60-70 tonne range, but treat that as arm waving until it's verified by volumetric or double integration analysis).

4) To elaborate on preliminary Argentinosaurus results (not included above), itÂ’s in the same size range as Puertasaurus, but basal titanosaurs may have had somewhat shorter tails (hence the smaller length) and the vertebrae aren't quite as wide as Puertasaurus, so my best guesstimate is that it loses on both accounts to it's lognkosaur relative, if only by a weeeee bit.

5) I didn't include Paralititan but I did scale it (hey, there's only so much space). It's large, but appears to be somewhat smaller than the Dallas specimen of Alamosaurus.

6) Speaking of Alamosaurus, I spent a lot of time trying to sort out who had the biggest fragmentary remains between Fowler & Sullivan (2010) and Guzman-Gutierrez & Palomino-Sanchez (2006). The tibia from Mexico is easily biggest (see gray silhouette behind the main Alamosaurus), but foreground skeletal here is based on Fowler and Sullivan's largest specimen (an isolated tail vertebrae) which happens to be from animal almost exactly the same size as the specimen on display at the Perot Museum of Nature and Science. Of course at this point we don't know for sure if the mexican tibia is truly Alamosaurus, or something new.

6) Brachiosaurus has long been abandoned in discussions of who is the largest dinosaur, but I'm not sure that's a good idea. The skeletal above is restored to the size of the type specimen, but some of the Utah specimens may be larger. The very broad-gutted Puertasaurus ekes out a larger size, but with such small sample sizes I don't think Brachiosaurus can actually be ruled out at the species level.

7) On the other hand, the significantly less robust Giraffatitan probably can be ruled out despite being quite tall.

8) While titanosaurs are generally heavier than diplodocids, very large Apatosaurus specimens appear to fit comfortably in the same size class. In addition to the Oklahoma specimen I have seen a few other (unpublished) apatosaur specimens that at least rival it in size.

So there you have it. If you have any other questions hit me up in the comments section below.

[theropod]

5. at paleoking.blogspot.co.at/2011/11/15-biggest-dinosaurs-youve-never-heard.html

The sacrum seems to be about 1,6m long
For comparison, the sacrum of B. althithorax' holotype is about 95cm long, based on scalebars in Taylor, 2009.

1,6/0,95*~23=~39m

The B. althithorax holotype was estimated at 28t by Taylor and this sacrum is nearly 70% bigger in linear terms. I think we have a new champ for animals known from decent remains (four sacral vertebrae, sufficiently described. Comparable to Puertasaurus' completeness, but these are articulated). Another sauropod that arguably exceeds the 100t mark.

www.paleoglot.org/files/Lapparent_60.pdf

A large sacrum initially drew attention, lying flat on the reg (Pl. II, fig.
3-4). This beautiful element must have been complete during its burial in the sediment, not far from large
trunks of silicified trees. The dorsal part was exposed by the erosion that delivered the piece today, and
several transverse processes were altered. Such as could be removed and reconstructed, this sauropod
sacrum presents an exceptional size: total length = 130 cm; diameter = 80 cm. The sacral vertebrae number
four, fused together. The first offers an enormous anterior disc, 23 cm wide and 22 cm tall. The third
sacral is 28 cm long and has a disc diameter of 20 cm; the keel is very marked on the ventral part, and the
diameter of the centrum in the middle is only 10 cm. The zygapophyses have wide and strongly twisted
stalks; they are extended up to 40 cm to the right and left of the neural canal; at their end, they are widened
in the shape of a powerful club and are solidly fused together there. In spite of its weight, we were able to
bring this element back to Paris.

Metacarpal III is a magnificent bone (Pl. VIII, fig. 6; X, fig. 3) that is striking in its dimensions:
length = 43 cm; width of the distal part = 16.5 cm; minimum width of the shaft in the median part = 7.5 cm.
Metacarpal IV is a bone of comparable size to the preceding one. Its calculated length gives 42
cm; the proximal part has a width of 13 cm; the minimum shaft diameter is 6.3 cm.

A phalanx from digit III (Pl. VIII, fig. 7; X, fig. 4), lay near the end of metacarpal III, moreover
displaced (Pl. III, fig. 3). Very well preserved, it is of a truly exceptional size if it is compared to other
sauropod phalanges, as the following table shows:

11,5cm long, proximal part 16,5cm wide, distal part 13,5cm wide (compared to 5,5, 8 and 8,5cm in an unspecified Diplodocus)

[coherentsheaf]

Jun 29, 2013 19:03:41 GMT 5 theropod said:

5. at paleoking.blogspot.co.at/2011/11/15-biggest-dinosaurs-youve-never-heard.html

The sacrum seems to be about 1,6m long
For comparison, the sacrum of B. althithorax' holotype is about 95cm long, based on scalebars in Taylor, 2009.

1,6/0,95*~23=~39m

The B. althithorax holotype was estimated at 28t by Taylor and this sacrum is nearly 70% bigger in linear terms. I think we have a new champ for animals known from decent remains (four sacral vertebrae, sufficiently described. Comparable to Puertasaurus' completeness, but these are articulated). Another sauropod that arguably exceeds the 100t mark.

www.paleoglot.org/files/Lapparent_60.pdf

A large sacrum initially drew attention, lying flat on the reg (Pl. II, fig.
3-4). This beautiful element must have been complete during its burial in the sediment, not far from large
trunks of silicified trees. The dorsal part was exposed by the erosion that delivered the piece today, and
several transverse processes were altered. Such as could be removed and reconstructed, this sauropod
sacrum presents an exceptional size: total length = 130 cm; diameter = 80 cm. The sacral vertebrae number
four, fused together. The first offers an enormous anterior disc, 23 cm wide and 22 cm tall. The third
sacral is 28 cm long and has a disc diameter of 20 cm; the keel is very marked on the ventral part, and the
diameter of the centrum in the middle is only 10 cm. The zygapophyses have wide and strongly twisted
stalks; they are extended up to 40 cm to the right and left of the neural canal; at their end, they are widened
in the shape of a powerful club and are solidly fused together there. In spite of its weight, we were able to
bring this element back to Paris.

Metacarpal III is a magnificent bone (Pl. VIII, fig. 6; X, fig. 3) that is striking in its dimensions:
length = 43 cm; width of the distal part = 16.5 cm; minimum width of the shaft in the median part = 7.5 cm.
Metacarpal IV is a bone of comparable size to the preceding one. Its calculated length gives 42
cm; the proximal part has a width of 13 cm; the minimum shaft diameter is 6.3 cm.

A phalanx from digit III (Pl. VIII, fig. 7; X, fig. 4), lay near the end of metacarpal III, moreover
displaced (Pl. III, fig. 3). Very well preserved, it is of a truly exceptional size if it is compared to other
sauropod phalanges, as the following table shows:

11,5cm long, proximal part 16,5cm wide, distal part 13,5cm wide (compared to 5,5, 8 and 8,5cm in an unspecified Diplodocus)

Afaik this is again a lost fossil. Not much to go on.

[theropod]

It is reported to have been brough back to Paris, so it might not be lost at all. It is also reasonably well-described and figured.

[Grey]

Me : Scott, what do you think of the various estimates we found on the internet about 250-300 tons sauropods, based on the Amphicoelias problematic or some very large footprints ? Real science or more or less educated enthusiasm ?

Scott Hartman : The latter, T----. There's a strong habit of inflating size estimates for dinosaurs (even among professionals - see "Seismosaurus"). Which isn't to say that some sauropods aren't truly gigantic, but for something as extraordinary as a 250-300 tonne sauropod you'd need extraordinary evidence.

[theropod]

You don't always have to exagerate the things you want to see people disagreeing with, you know? 100-200t is not the same as 250-300...


I would like to remind you of this (a response to your own comment I suspect from the characteristic space before the punctuation mark):

By contrast, there are, or at least were, remains of two sauropods — Amphicoelias fragillimus and Bruhathkayosaurus of course — which one could imagine massing that much without too much of stretch. Of course since both specimens have been lost or destroyed, it isn’t possible to say much about them, or even to be 100% certain that they ever existed and were as described. But I think we can be say 90% certain. And since it’s vanishingly unlikely that the one specimen ever found of each of these was the biggest they got, my gut feeling is that there very possibly were sauropods that massed 200 tonnes in life.

Yep, thatÂ’s blue-whale size.

Wow.

svpow.com/2010/02/19/how-big-was-amphicoelias-fragillimus-i-mean-really/

Mike Taylor has no problem with blue whale-sized sauropods, quite the opposite. "not being seriously suggested" is not a problem here, it is both suggested and accepted.

The guys also expressed no criticism of Zach Armstrong's figures, all this is perfectly valid.

You still seem to clinge to this older post. But we have to rely on what people accept now, not what they rebutted once!

[Grey]

Jun 30, 2013 21:24:27 GMT 5 theropod said:

You don't always have to exagerate the things you want to see people disagreeing with, you know? 100-200t is not the same as 250-300...

I have no problem with 100-200 tons as possibility, I have problem with 200-300 tons like proposed once by fragillimus, something you did not disagree with.

[Deleted]

~250-300 tonne sauropods are ridiculous.

~200-220 tonnes for A. fragillimus works for me, with freak specimens possibly reaching close to the 250-tonne mark.

A while back...

blaze gave me these:
"Haplocanthosaurus (left) femur length from Wilhite (2003).

CMNH10380 1751 mm
CM572 1258 mm
USNM4275 1089 mm

CMNH10380 is estimated at 16m long and 12.8 tonnes and CM572 at 12m and 5 tonnes by Gregory Paul."

I then made a calculation:

"Amphicoelias altus has a 1.77-meter long femur^[1], thus:

Based on CMNH10380, it would be about ~16.174 meters long with a mass of ~13.22 tonnes.

Based on CM572, it would be about ~16.88 meters long with a mass of ~13.93 tonnes.

Amphicoelias altus has a last trunk vertebra height of 1.075 m^[1], and Amphicoelias fragillimus about 2.7 m^[2], so based on the CMNH10380-based estimate, it would be about:
~40.62 meters long, and ~209.46 tonnes in mass

Based on the CM572-based estimate, the size would be:
~42.4 meters long, with a mass of ~220.71 tonnes"

I did not take into account the neck allometry, which would have increased the total length.

Reference list for my calculation:
[1] gspauldino.com/DinoArtSauropods.pdf
[2] Carpenter, K. (2006). "Biggest of the big: a critical re-evaluation of the mega-sauropod Amphicoelias fragillimus."

This quote below is also quite relevant:

"The surprising slenderness of the giant Amphicoelias vertebra and the Argentinosaurus tibia suggests that even they were not close to the maximum size possible! Indeed, it is hardly likely that we have found the biggest sauropods, so species as heavy as 200 tonne blue whales cannot be ruled out." -Greg Paul

[theropod]

Jun 30, 2013 21:30:13 GMT 5 Grey said:

Jun 30, 2013 21:24:27 GMT 5 theropod said:

You don't always have to exagerate the things you want to see people disagreeing with, you know? 100-200t is not the same as 250-300...

I have no problem with 100-200 tons as possibility, I have problem with 200-300 tons like proposed once by fragillimus, something you did not disagree with.

Neither did I formally disagree with 50-100t (coherentsheaf, stomatopod), nor with those who chose to not take A. fragillimus into account, did I? Are you now starting to accuse me of "unscientificness" because I did not disagree with everything that has been stated? Shall I now formally disagree with every statement I can find on the internet unless it is exactly my opinion?
I was, again, a bit busy arguing with you, and had no time rebutting someone who doesn't just change his opinion based on the available data, but also at least used similar reasoning, tough more liberal.
Sorry if I'm getting paranoid, but you started it.

What I suggest: 120-200t for Amphicoelias by Carpenter's method, possibility of smaller or larger sizes with other diplodocids (please give me suggestions, if possible with a paper to check the measurements)

Approximately 100-200t for the plagne trackmaker, again possibility of smaller or larger sizes, depending on the footprint's preservation (undertrack/overtrack? eroded or collapsed?)

Both ends equally likely

You seem to agree with this, so why continue to ridicule me and others?

[Grey]

Fine with this. But I spit on the establishment of any fact from this, including fragillimus post in deviantart "255 tons and the largest animal ever to live".