|
|
Post by dinosauria101 on Aug 17, 2019 8:59:43 GMT 5
Liopleurodon vs Titanoboa  |
|
|
|
Post by dinosauria101 on Aug 17, 2019 8:59:58 GMT 5
Basilosaurus vs Predator X  |
|
|
|
Post by dinosauria101 on Aug 17, 2019 9:00:20 GMT 5
Brygmophyseter vs Predator X  |
|
|
|
Post by dinosauria101 on Aug 17, 2019 9:02:29 GMT 5
 Triceratops vs Purussaurus |
|
|
|
Post by dinosauria101 on Aug 17, 2019 9:03:12 GMT 5
 Therizinosaurus vs Dacentrurus |
|
|
|
Post by dinosauria101 on Aug 17, 2019 9:24:11 GMT 5
Styracosaurus vs Mamenchisaurus youngi  |
|
|
|
Post by jdangerousdinosaur on Aug 18, 2019 4:09:22 GMT 5
MCZ 4371 Deinonychus skull compared with extrapolated skull size for MCF-PVPH-108-145, the giant 13.6 meter, 8.5 ton Mapusaurus Like we have discussed before it is unlikely that MCF-PVPH-108-145 is really that large Franoys has said this to a user that brought up the 13-meter-long estimates for Mapusaurus Yes, MCF PVPH 108.145 (which is the catalog number used here) is a 7.2 cm long piece of the pubis shaft (important to mention that the whole pubis shaft of these animals would be over 1 meter long), which is 7.5*10 cm wide, a 10% wider (or about 0.75-1 cm wider) than the Giganotosaurus pubis on its narrowest portion; however; we can't posibly know if the portion of the Mapusaurus pubes belongs to the part of the shaft that would actually be narrowest; and the comparison between one and the other is just based on that paper (in which the exact dimensions of Giganotosaurus pubes aren't reported, only the 10% wider figure). This bone is part of the bones my Mapusaurus skeletal is scaled to; as in all likelyhood, there are more remains from this particular individual. The metatarsals suggest a minimum of 7 individuals, all substantially smaller than the Giganotosaurus type; then between the remaining bones several of them suggest an individual of similar size, unless you split each bone into a different specimen and then get at least 6 Giganotosaurus holotype sized individuals. There are a number of remains that match very well and when put together, they suggest an animal of almost the same exact dimensions to the Giganotosaurus holotype (the vertebral remains are the same exact size, suggesting the same size for the axial skeleton, or the same body length), just with slightly different proportions, for example a slightly longer but much narrower fibula proportionally, a shorter snout with a head about as deep but narrower and proportionally shorter, etc; which is something that is expected as inter-generic variation. Even if the pubes really was a 10% wider, or even a 10% bigger overall (the last case is what I used for my skeletal, so I asumed a generous scenario that I could revert soon); It still makes sense to assign them to the same individual as the other remains considering Mapusaurus and Giganotosaurus are different genera and geological distortion the authors of the paper also cite a size equal to Giganotosaurus, or 12.2 m long as written in the paper; as the maximum size for Mapusaurus) www.deviantart.com/franoys/art/Giant-predatory-dinosaurs-comparison-616409616?offset=50#comments |
|
|
|
Post by dinosauria101 on Aug 18, 2019 7:30:39 GMT 5
MCZ 4371 Deinonychus skull compared with extrapolated skull size for MCF-PVPH-108-145, the giant 13.6 meter, 8.5 ton Mapusaurus Like we have discussed before it is unlikely that MCF-PVPH-108-145 is really that large Franoys has said this to a user that brought up the 13-meter-long estimates for Mapusaurus Yes, MCF PVPH 108.145 (which is the catalog number used here) is a 7.2 cm long piece of the pubis shaft (important to mention that the whole pubis shaft of these animals would be over 1 meter long), which is 7.5*10 cm wide, a 10% wider (or about 0.75-1 cm wider) than the Giganotosaurus pubis on its narrowest portion; however; we can't posibly know if the portion of the Mapusaurus pubes belongs to the part of the shaft that would actually be narrowest; and the comparison between one and the other is just based on that paper (in which the exact dimensions of Giganotosaurus pubes aren't reported, only the 10% wider figure). This bone is part of the bones my Mapusaurus skeletal is scaled to; as in all likelyhood, there are more remains from this particular individual. The metatarsals suggest a minimum of 7 individuals, all substantially smaller than the Giganotosaurus type; then between the remaining bones several of them suggest an individual of similar size, unless you split each bone into a different specimen and then get at least 6 Giganotosaurus holotype sized individuals. There are a number of remains that match very well and when put together, they suggest an animal of almost the same exact dimensions to the Giganotosaurus holotype (the vertebral remains are the same exact size, suggesting the same size for the axial skeleton, or the same body length), just with slightly different proportions, for example a slightly longer but much narrower fibula proportionally, a shorter snout with a head about as deep but narrower and proportionally shorter, etc; which is something that is expected as inter-generic variation. Even if the pubes really was a 10% wider, or even a 10% bigger overall (the last case is what I used for my skeletal, so I asumed a generous scenario that I could revert soon); It still makes sense to assign them to the same individual as the other remains considering Mapusaurus and Giganotosaurus are different genera and geological distortion the authors of the paper also cite a size equal to Giganotosaurus, or 12.2 m long as written in the paper; as the maximum size for Mapusaurus) www.deviantart.com/franoys/art/Giant-predatory-dinosaurs-comparison-616409616?offset=50#commentsYou may actually want to talk to theropod about that; they made the skull. But thanks! |
|
|
|
Post by dinosauria101 on Aug 18, 2019 22:47:23 GMT 5
Various Spinosaurus specimens by rock  |
|
|
|
Post by dinosauria101 on Aug 19, 2019 2:58:31 GMT 5
Snipped from Google: Record killer whale vs Spinosaurus  |
|
|
|
Post by dinosauria101 on Aug 19, 2019 7:45:18 GMT 5
Neotype and holotype of Carcharodontosaurus saharicus vs holotype of iguidensis  |
|
|
|
Post by dinosauria101 on Aug 19, 2019 20:02:48 GMT 5
By gigadino96: Carch vs Giga  |
|
|
|
Post by Verdugo on Aug 20, 2019 20:51:54 GMT 5
theropod I'm aware that the results from Wroe 2005 are just estimates, however, i'm not aware of the nature of the Valkenburgh's equation that they used. I suppose you got the point then. However, the results from Wroe 2005 are not particularly outrageous when compared to results from other papers (in my previous post). Anyway, how about Per Christiansen (2007) though? According to them: "Body masses were assigned to the specimens based on their skull sizes (premaxilla–occipital condyles), using a sample of 24 specimens, representing 11 different species of felids, in which body masses had been found either shortly prior to or immediately after death" They even provide an equation for BM and CBL (condylo-basal) in the Method section:  I suppose we can put whatever BM we want in and solve for SL and we can get a fairly realistic CBL skull size for a Pantherine of that size. Infinity Blade How about Bates 2009 though? They used a volumetric method and also obtained a BM of 7.65 tonnes which is similar to that of Franoys. On the other hand, Hutchinson 2011 got a 5.9 tonnes min weight for Stan based on their volumetric model. I suppose any estimates that fall between the range 5.9 - 7.65 tonnes should still be considered reasonable. Or you could just use an average of these values which is about 6.8 tonnes. The average result is therefore probably also congruent with with Blaze's 'close to 7 tonnes' estimate. I did not see Larramendi's estimate for Stan? Maybe he talked about it some where in the comments but i'm unable to find it. Anyway, regarding his estimate for Sue, one could also argue that his estimate may be a bit too conservative. For instance, his estimate is vastly less than the 9.5 tonnes volumetric estimate from Hutchinson 2011. It's even less than the 8.4 tonnes estimate from Scott Hartman, who already considered his model to be slightly on the conservative side: Tyrannosaurs have almost comically wide abdomens (and mine is not as broad as some other workers and some mounts show), while Giganotosaurus has the typical allosaur-grade torso. 5) Although Tyrannosaurus seems likely to have had stronger calves I used the exact same muscle reconstruction to try and make the comparison more of an apples to apples affair
|
|
|
|
Post by theropod on Aug 20, 2019 22:19:51 GMT 5
Verdugo : Yes, that was my point. Had Van Valkenburgh’s equation been more solid (I was hoping for something more like what you just posted), it could have even been more useful than a simple measured weight and skull length for one specimen, but due to the issues with it, I wouldn’t trust the masses listed in Wroe et al.. I just wanted to point out they aren’t useful datapoints due to not being independent measurements, but I thought the method might be useful, and then looking for that I stumbled across the rather obvious problems with it (insufficient sample size and unreliable weight figures). The equation you posted seems good though! Regarding the stronger calves, I must disagree with Hartman, carnosaur tibiae are more robust and have larger cnemial crests those of tyrannosaurs, so at similar length they would be expected to have at least equally robust calves. T. rex-sized carcharodontosaurs either don’t have preserved tibiae (Large Mapusaurus and Acrocanthosaurus specimens, Tyrannotitan, Carcharodontosaurus), or their tibiae aren’t figured anywhere ( Giganotosaurus), and of course larger animals have more robust tibiae due to allometry, so we can’t compare T. rex to Allosaurus, but here is the tibia of Gorgosaurus libratus CMN 350 compared to Allosaurus fragilis USNM 4734 scaled to the same size. The Gorgosaurus is still a considerably larger specimen (Femur 93 vs 77 cm, tibia 84 vs 69 cm), yet the shafts are similarly robust at a given length and the proximal part with the cnemial crest in Allosaurus is much larger, suggesting more robust calf musculature.  A: Lambe, L.M. 1917. The Cretaceous theropodous dinosaur Gorgosaurus. In Canada Geological Survey. Memoir 100. Government Printing Bureau, Ottawa
B: Gilmore, C.W. 1920. Osteology of the carnivorous Dinosauria in the United States National museum: with special reference to the genera Antrodemus (Allosaurus) and Ceratosaurus. US Government printing office, Washington DC.
Here is Mapusaurus MCF-PVPH-108.68 (104cm) compared to T. rex FMNH PR 2081 (114cm): 
A: Coria, R.A. and Currie, P.J. 2006. A new carcharodontosaurid (Dinosauria, Theropoda) from the Upper Cretaceous of Argentina. Geodiversitas 28 (1): 71–118.
B: Brochu, C.A. 2003. Osteology of Tyrannosaurus rex: insights from a nearly complete skeleton and high-resolution computed tomographic analysis of the skull. Journal of Vertebrate Paleontology 22 (sup4): 1–138.
|
|
|
|
Post by Infinity Blade on Aug 20, 2019 23:18:13 GMT 5
Yeah, I said on the previous page that he mentioned it in the comments section of his Sue skeletal page. He says the following: According to SpinoInWonderland (broly), using a density of ~0.915 kg/liter (although, averaging Hartman's varying values of density for the body, which are 1.0 for the limbs and tail; 0.9 for the neck and torso; and 0.8 for the head, we get 0.9 kg/liter, which is slightly lower), we get 6,260 kg. To be perfectly fair, that is still within the range of volumetric estimates for Stan, as you point out that Hutchinson et al. (2011) get 5.9t using the minimum model (although to be fairer, as I'll point out below, I'm not sure how to feel about Hutchinson's mass estimates). Hartman's estimate is still approximately consistent with Larramendi's. As for Hutchinson et al. (2011), I'm not 100% sure I trust the 9.5t value from Hutchinson et al., but then again, it's not really my place to debate that. I'm pretty sure you and theropod (and other members) had discussions on that before I even joined Carnivora, so I'm guessing both of you know the nitty gritty of that better than I do. theropod Actually, the T. rex at least looks like it has a similarly-sized cnemial crest to Mapusaurus. As for Gorgosaurus, Pete Larson-> has a few pics of a Gorgosaurus skeleton mount and, at least from what I can gleam, the cnemial crest looks to be much more prominent than Lambe illustrated. What do you think? |
|
