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First of all, the results:

GigaGDI2 by Franoys


GigaGDIresults by Franoys

Conclussions , methodology, and anatomical references: 

For those who don't know which method was used, I recommend reading the previous journal entry, about a mathematical anaylsis on Spinosaurus mass A mathematical analysis on Spinosaurus mass.Description of the method:
Graphical double integration performed by Matblab program.
We calculated the mass of the North african theropod dinosaur Spinosaurus aegyptiacus, using a graphical double integration method. We believe GDI is in itself, and without a doubt, one of the best methods to calculatte the mass of extint organisms, and the best that can be used using a multi views silhouette from the animal. The method averages a big amount of eliptical sections to aproximate the volume of a complex 3D object. The more eliptical sections, the more accurate the result will be, when a number of slices made is surpassed the result will be almost real life-like.
This matlab program utilizes digital image processing technology to analize two silhouettes from different views. It counts the number of non white pixels in every pixel-wide column from the image, and produces one slice per pixel. In response, the program is extremely sensitive to irregularities in the silho
, another legendary carnivorous dinosaur; and this excelent post by SVPOW. svpow.com/2011/01/20/tutorial-…

Overall the method intends to construct a simplified 3D model of the animal by building eliptical cross sections and adding them up, given two views of each of it's body sections. The analysis is performed by a matlab mathematical script with pixel accuracy.

The skeletal used is my own bet on the animal. Sadly, and despite more than 22 years having passed since the animal was first (and very briefly) described, most of it's material is not described in detail, specially the axial skeleton. No photographs, ilustrations, measurement tables, nothing. So even if I used my skeletal for the GDI, the axial skeleton ( the vertebral column) had to be scaled after :iconscotthartman: work. I didn't have much of a choice in that regard.

Most of the skull and the apendicular material has however been mentioned, briefly described, and has several measurements published in the literature (Coria 2003, Coria and Currie 2006, Carrano 2012, Canale 2014, Canale& Carbajal 2015, and other studies, a good deal of them are compiled in the theropod database) I tried for the skeletal to be as up to date and to match as many of the measurements and the descriptions in Coria and Currie 2006 and the other studies as much as possible. The missing elements of the skeleton, like the forelimbs or the feet, were restored after my Tyrannotitan skeletal.

The top view is scaled and drawn after Acrocanthosaurus (Bates 2008) , a similarly sized Carcharodontosaurid, edited to have similar proportions to those of Giganotosaurus. By superimposing Hartman's Giganotosaurus top view with the dorsal view of Bates et al Acrocanthosaurus, it seems to be what he did, or at the very least the results are pretty much identical. I used Hartman's dorsal view to have an idea of how much soft tissue should I add for it to be a fair comparison with other theropod GDIs.

The results pretty much replicate his estimation (6800 kgs), despite several bones differing a substantial deal from his version. They are also coherent with other mass estimations published for Mucpv Ch1 (Mazzeta et al 2004; 6510 kg , Campione et al. 2014;  6349 kg,   Seebacher 2001 ; 6,594.8 kg)

Link to Giganotosaurus restoration:

Giganotosaurus carolinii skeletal diagram. by Franoys
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:iconthedinorocker:
thedinorocker Featured By Owner Feb 2, 2017
Different methods with similar result corroborate each other, not surprise your est. Is very similar with Hartman's one and other published
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:iconfranoys:
Franoys Featured By Owner Feb 4, 2017
Indeed, and thank you for your comment!
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:iconyty2000:
yty2000 Featured By Owner Jan 27, 2017
I have a question regarding the density of the animal. Muscles are denser than water, so are bones.
Here's a study on passerine bird bone density: rspb.royalsocietypublishing.or…

So wouldn't the all the body parts, which are mostly bones and soft muscles, except the torso, have a density greater than 1kg/L?
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:iconthedinorocker:
thedinorocker Featured By Owner Jan 28, 2017
The head have a lot of empty space so is the part with the lower general density, and all other body districts (except the torso) have density = 1
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:iconyty2000:
yty2000 Featured By Owner Jan 28, 2017
Well maybe the head is less than 1 due to the respiratory system, but the limbs and tail's gotta be denser.
In the link I provide above, passerine bird limb bones have density above 1.8g/ml, which is a lot dense that water. Muscles are slightly denser than water, which will make limbs (mostly muscles and bones) way more dense than water.
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:iconfranoys:
Franoys Featured By Owner Edited Jan 29, 2017
The density of the bone tissue is obviously high however the bones themselves are empty in the inside, aka not the whole volume that the external appereance of the bone suggest is woven bone, as you can see in this ilustration from the Ibrahim et al supplementary materials:  

drive.google.com/open?id=0B-K0…

Furthermore, despite what the lateral view might seem to suggest the bone doesn't make up for most of the limb volume, in fact it wouldn't even make up for a even 1/10th of the volume of the limb considering the three dimensions, the muscle and fat does occupy the majority of the volume.
Fat has a density much inferior to that of water, 0.9 kg/l or less. The muscle itself is not all fiber and has several different types of tissue including addipose tissue. And the tissues of course are also not dry, they are hydratated; water makes up for 75% of the volume of a muscle or more; the mean of the density in a human muscle is between 1-1.1 kg/l, and we would be talking of a difference of 10% maximum with that of water. Then add blood to the equation. All of this makes that in the end, an overall density of 1 for the limbs is a good aproximation.
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:iconyty2000:
yty2000 Featured By Owner Feb 6, 2017
Thanks for you explanation. If we assume that fat occupy about the same volume as bones, then the resulting density will probably be over 1, maybe 1.1g/ml. Anyways, it won't affect the overall mass very much, like less than 5%.
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:iconfranoys:
Franoys Featured By Owner Edited Feb 6, 2017
But the volume that the bones occupy has not a density higher than water because they are hollow in the inside; asuming a density equal to that of the leg bone of Allosaurus the volume that the bones occupy wold have a density of 0.6 kg/l, also don't forget that muscles having a density of 1.1 is the extreme upper bound, the density is probably closer to 1.05 or 1.06 kg/l, then you have blood and other type of tissues like the nerves which have a similar density as fat, with theese kind of densities I don't think 1.1 kg/l is likely.
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:iconyty2000:
yty2000 Featured By Owner Feb 6, 2017
I see your point. I cannot provide quantified values for bone volume or the empty space inside the bone. Just a simple example, if you gently submerge chicken limbs into a pot of water, they sink. If the density is equal to water, wouldn't the chicken float in whatever depth you submerge it?
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:iconfranoys:
Franoys Featured By Owner Edited Feb 6, 2017
I asume you are talking about cut limbs in a long dead animal, and in that case the tissues have lost a significant portion of their hydratation and the dead celulae lost almost any kind of gas that they could have in their citoplasm and organelles, in that situation of dehydratation and degradtion the density of the tissues would be higher, but they wouldn't be how the they would be in the animal in life. I did provide density values of the bones with the measured densities on femoral shaft thin sections from the Ibrahim et al 2014 study.

Well and also the limbs of a chicken aren't really comparable to those of a giant theropod in soft tissue levels.
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(1 Reply)
:iconanonymousllama428:
AnonymousLlama428 Featured By Owner Jan 27, 2017  Hobbyist General Artist
KEWL
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:iconbh1324:
bh1324 Featured By Owner Jan 27, 2017
Very interesting as always!
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:iconkirkseven:
kirkseven Featured By Owner Jan 26, 2017
This is an excellent read.

Good info.
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