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Dreadnoughtus - huge, but not the 'hugest'

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Massive props to the authors of the Dreadnoughtus papers, this has to be one of the best documented and figured sauropods of all time, and in quite a short span of time (the specimen was just named four years ago!).

Of course what everyone wants to discuss is the size of Dreadnoughtus. The mass has been downsized a few times since the initial description's claim of 59 tonnes; I don't have anything new to add other than what has been said previously (i.e. it wasn't as big as Argentinosaurus, Patagotitan, the Mexico "Alamosaurus" or Puertasaurus).

Length-wise I get 23 meters along the curve of the back, a bit shorter than the 26 meters in the original paper. Most of that is due to my interpreting a large cervical as the 10th rather than the 9th cervical. Doing so has a knock-on effect that shortens the estimate for most of the cervical vertebrae. It's still got a heck of a long neck, even for a titanosaur. I'd be remiss not to point out that there's no way to tell which position is correct at this point - we will need more Dreadnoughtus cervicals to know for certain, but in the absence of any additional data I'm going with the more conservative interpretation.
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anonymous's avatar
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Thalassophoneus's avatar
Why is Dreadnoughtus usually restored with a skull like that of Tapuiasaurus? Was Tapuiasaurus a close relative of Lognkosauria?
Thalassophoneus's avatar
Also, it seems to me like on your skeletal the 11th rather than the 10th cervical looks more similar to the one shown on the paper in terms of elongation.
Santi801's avatar
Were the holotypes juveniles? 
The-Nerdinator's avatar
The holotype was an adolescent on death.
Stuchlik's avatar
And according to yours work, which one will be the heaviest? I mean Argentinosaurus, Alamosaurus, Puertasaurus or Patagotitan? Is possible to check this with GDI?
DrScottHartman's avatar
I haven't done GDI estimates, and honestly with what is known the error bars would be too big to tell for sure anyhow. But Patagotitan looks almost exactly the same size as my estimate for Puertasaurus (which assumes it's a scaled up Futalognkosaurus), and both have smaller torsos (in side view) than Argentinosaurus, so if they are all equally rotund (which we don't know) I'd assume Argentinosaurus is larger. Scaling my composite adult Alamosaurus isometrically up to the size of the Mexican tibia also puts in in the same ballpark as Argentinosaurus, but again, we don't know enough about the three-dimensional shape of the rib cage to really know which is the largest with any precision.
PedroSalas's avatar
I'm happy you did this. It turned out very elegant.
I've wondered many times if sauropods could have had a partly scaly and partly pachyderm skin, like tortoises have.
Archanubis's avatar
Which one was the one that was said to be the biggest sauropod with the best fossil material, this or Patagotitan?  I thought it was Dreadnaughtus, but maybe not...
DrScottHartman's avatar
It was said about both. First for Dreadnoughtus in 2014 (though subsequent papers have challenged the size claim) and more recently for Patagotitan. Both have significant portions of the skeleton known, though neither are known from a single articulated specimen - Dreadnoughtus is known from two specimens, while Patagotitan is known from several. It's easier to cross-scale elements in Dreadnoughtus, and for now at least Dreadnoughtus is described in much greater detail.
Snowflake-Tinystar's avatar
Would that tail really be long/heavy enough to keep it from tipping? 
DrScottHartman's avatar
What Majestic says - note for example that brachiosaurs had even shorter tails. In all likelihood the animals would not have fallen over even if their tails were surgically removed. The tail is less for balance in quadrupeds than it is an anchor for the most important leg retraction muscles.
Majestic-Colossus's avatar
The neck is much lighter than it seems because its density is low. Most of the animal's mass is located in the torso, which is probably a lot heavier than tail and neck put together.
RagnarokOffical's avatar
You guys ever just think “Woah these creatures were real, I am walking on the same planet as giants did millions of years ago.”
DrScottHartman's avatar
I tend to have those feelings of reverie in the field more than when I'm working on reconstructions, but it's certainly an experience I've had more than once.
Spiritstrike91's avatar
Dreadnoughtus certainly lives up to its name: "fearer of nothing".

Not the biggest guy, but a dino that will give you a run for its money. Kudos to the love of sauropods!
DrScottHartman's avatar
Yeah, it's a great name, and it's hard to imagine that full grown adults (of which these two specimens were not!) would have had much of anything to fear.
AnekoWolf's avatar
asari13's avatar
thedinorocker's avatar
This Taxon and Patagotitan truly deserve your touch, they are fairly complete and good described by giant titanosaur standard.
Truly a Great work!
DrScottHartman's avatar
Thanks. Patagotitan is a WIP, though it's not figured nearly as well (yet) as Dreadnoughtus is.
Majestic-Colossus's avatar
I completely agree! Also, I can't wait for his touch on Argentinosaurus!
DrScottHartman's avatar
Already done, just waiting for when it can be set loose.
Majestic-Colossus's avatar
Cool! By the way, does Patagotitan's description change anything for the other lognkosaurs? I mean, are your Futalognokosaurus and Puertasaurus as good as always, or updates need to be made? What about Argentinosaurus? Did Patagotitan's material help you make up for the poor preservation of Argentinosaurus? 

I'm asking this because, if I recall correctly, a recent analysis put Patagotitan extremely close to Argentinosaurus.
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