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Carnivorous dinosaurs other than the famous t-rex and spinosaurus..
Carnivorous dinosaurs other than the famous t-rex and spinosaurus..
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Carnivorous dinosaurs other than the famous t-rex and spinosaurus..
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I'd like to address some of Scott Hartman's statements in regards to Tyrannosaurus and Giganotosaurus size.
On his website (link), when comparing the sizes of Tyrannosaurus and Giganotosaurus, Scott Hartman states "As near as I can tell, despite Tyrannosaurus and Giganotosaurus appearing similar in size in side view, there is little question that T. rex is actually the larger theropod based on known specimens." Many read this and believe Tyrannosaurus to undoubtedly be the larger, but this isn't necessarily true, for several reasons. Here is why: -As I have gone over above, there are several factors that end up underscoring the mass of Hartman's Giganotosaurus by a good bit compared to what the real animal probably weighed (such as too little soft tissue and a significantly too shallow torso); using the GDI of GetAwayTrike's likely better skeletal, we have a mass range of ~7.53-9.49 tonnes for the 2 Giganotosaurus specimens, compared to the ~6.8-8.2 tonnes of Hartman's skeletal as-is. The upper end of this (~9.49 tonnes) outmasses the estimated ~8.4 tonnes for Sue, thus when comparing Sue and MUCPv-95 as Hartman did, but using GetAwayTrike's skeletal, Giganotosaurus would be the larger theropod based on known specimens, by well over a ton. -Scott Hartman is using Sue as the representative of the entire species; not the best idea as it is a very large and old specimen in a sample size of over 30, and many adults such as Bucky and B-rex are significantly smaller than it. Moreover, when looking at our entire sample size of Tyrannosaurus adults, the average is about 6 tonnes as I have went over in the Tyrannosaurus thread, which both Giganotosaurus specimens and the average mass of them are larger than, by 2.51 tonnes. -Even if Sue was larger than MUCPv-95, that wouldn't necessarily mean Tyrannosaurus was the larger animal as a species - we would, as previously stated, need to look at the mean mass of both species based on all specimens of both species to determine which was larger as it is a far better sample than merely maximum vs maximum. As previously stated in this thread, there are many adult Tyrannosaurus specimens that both specimens of Giganotosaurus match or outsize (such as UCMP 118742, BHI 3033, MOR 980, LACM 23844, MOR 008, MOR 555, CM 1400, AMNH 5027, RTMP 81.6.1, RTMP 81.12.1, BHI 4182, MOR 1128, CM 9380, MOR 1125, and USNM 6183). 
" Closely related to the larger and more recent Tyrannosaurus, Daspletosaurus had dozens of large, sharp teeth and the small forelimbs typical of tyrannosaurids. Daspletosaurus was at the top of the food chain, probably preying on large dinosaurs such as ceratopsids and hadrosaurs.
Art: Raúl Martin. "
This post completes and follows the post #199.
Wiehenvenator was a megalosaurid from the Middle Jurassic in Germany (165 millions years). Length: 8-10 meters long Weight: 2 tons.  *This image is copyright of its original author Wiehenvenator Albati, the monster of Minden.
" Torvosaurus infographic
Torvosaurus belongs to a group of megalosaurid theropod dinosaurs. There were two species of Torvosaurus that lived in North America and Europe, 153 to 148 million years ago (late Jurassic). First fossil of Torvosaurus was found in 1972 in Colorado and fully-described 7 years later. Aside from Colorado, fossils of Torvosaurus were also found in Utah, Wyoming and on the Iberian peninsula (Europe). Torvosaurus lived in the floodplains, wetlands and forests. It was one of the largest and fiercest predators of Jurassic period. Interesting Torvosaurus Facts: Torvosaurus was able to reach length of 33 to 40 feet and weight of 2 to 5 tons.European species of Torvosaurus: Torvosaurus gurneyi was slightly smaller than its American cousin: Torvosaurus tanneri. Despite slightly smaller size, it was still the largest predator of Jurassic Europe. Torvosaurus was closely related to Megalosaurus, large carnivorous dinosaur that lived during the mid Jurassic period in the southern parts of England. Torvosaurus had elongated, narrow snout, heavy body, powerful hind legs and short, but strong arms equipped with long, sharp claws (shaped like talons of eagle). Some researchers believe that claw on the thumb was especially good developed. Torvosaurus had long tail that was very stiff at the base."
" One of the best in his family. Suchomimus tenerensis by the hands of the talented @saraphis_creations , the colors used hurl a swampy animal that should have been frightening when fishing, even in family members like Baryonix, dinosaur remains were found, indicating that they hunted whenever possible.
Follow @saraphis_creations to view and buy amazing dinosaurs. "
" Utahraptor gained fame by starring in Jurassic Park. No you say, it was Velociraptor. Indeed, moviemaker Steven Spielberg used the name, Velociraptor in his movies, however, in reality, Velociraptor is less than half the size of the dinosaurs depicted in Jurassic Park. Utahraptor was found the year that Jurassic Park came out and gave scientific credence to the large-sized raptors in the movies. It’s just that they are really utahraptors not velociraptors!
A very large, deep, thin, blade-like claw core bone was uncovered in October, 1991, by Carl Limone, Preparator at the CEU Prehistoric Museum. The new claw’s similarity to the slashing claw on the foot of Deinonychus and Velociraptor of the dromaeosaurid family of dinosaurs was immediately recognized by the quarry personnel. The dromaeosaurid dinosaurs were the most savage predators, pound for pound, ever to have walked the earth. At 9 inches long, the bony core supported a claw which in life would have been 15 inches long, indicating an animal twice the size of Deinonychus. Additional finds, including bones of the skull and upper jaw, support this conclusion Art: Riccardo Frapiccini "
Theropod1's Carcharodontosaurus skull reconstruction (SGM-DIN 1) at 162 cm
 *This image is copyright of its original author SpinoInWonderland's SGM-DIN 1 (I believe this is about 161 cm)  *This image is copyright of its original author For those of you who have not seen my earlier post, this likely belonged to a >13 meter, >9 tonne animal.
" the new analysis includes two previously unstudied fossil specimens from Arizona, providing the first clear picture of what Dilophosaurus was like in life. Rather than a small dinosaur that relied on gimmicks such as venom and a neck frill to subdue its prey, Dilophosaurus was a powerful predator and one of the largest land animals in North America when it lived during the early Jurassic period, which lasted from about 201 to 174 million years ago.
“It’s a lot bigger than people would think from watching Jurassic Park,” Marsh says." Artist: @paleorex
Some basal megalosauroids such as Xuanhanosaurus (link), Marshosaurus (link), and Eustreptospondylus (link) seem to have proportionally MASSIVE heads (all 3 are around 200 kg yet their skulls are all 60 cm at least), yet their forearms are also very large as well, about the same proportionally as a lion, tiger or grizzly bear, 60-65 cm long for a 200-250+ kg specimen of any of the 3 (link, link).
I suspect these animals may have been more efficient predators than modern grappling carnivores such as big cats or bears, as well as more efficient than modern large jawed predators such as canines, hyenas, or crocodilians, since they have the large, deadly jaws of a canine, hyena or crocodile, but also the powerful grappling forelimbs of a big cat or bear.
For those of you who have not seen my post about it in the Giganotosaurus thread, both species of Giganotosaurus (including what some of you consider Mapusaurus, G. roseae) are probably getting a bit of a change in size, at least if we go by the corrected version of Greg Paul's skeletal.
These estimates are the most current and up to date that I am aware of for both, and place them substantially larger than often thought. On his website, he estimates the G. carolinii holotype at 6850 kg. However, there are 2 issues with his skeletal underscoring the mass: -He has used a specific gravity of 0.85 when it should have been a mean of about 0.97 following his 2020 publication with Asier Larramendi on the specific gravities of animals. -In his skeletal, the pectoral girdle as preserved is taken as complete when it isn't (the same issue that plagues Hartman's skeletal), thus making the chest much shallower than it would be. As I have went over in this thread, the correction factor for that based on SpinoInWonderland's GDI (multiply volume by 0.97) of GetAwayTrike's skeletal is (the percentage of the old densities) 6800 to 7530 kg. Correcting both of these, Greg Paul's skeletal of Giganotosaurus goes to 8660 kg for MUCPv-Ch1, which would then be 11530 kg for MUCPv-95* and the average of both of them being 10100 kg if we were to use his skeletal as the base. For comparison, SpinoInWonderland's above GDI suggests a total size range of 7980-10620 kg, with a 9300 kg average, and his GDI of his own skeletal roughly matches the one he did of GetAwayTrike's. The mean of these, which I will be assuming, is 8320-11100 kg, average of 9700 kg. For length, we have ranges of 12.45-13.7 meters respectively, and 12.3-13.5 meters respectively. I will be assuming the mean of these as well, which is roughly 12.4-13.6 meters. This gives us a total average size of 13.1 meters and 9700 kg for the 2 known specimens of Giganotosaurus. *Some may wonder why I assume MUCPv-95 to be 10% larger instead of 6.5-8% larger. This image shows MUCPv-95 is 10% deeper at its anterior symphysis, and I view this as a better estimate than, say, 6.5% because I can replicate it directly. As for G. roseae, this probably means several specimens from it are larger than expected. First of all, for perspective, the tibia and fibula of MUCPv-Ch1 are 99 and 98.5 cm long, according to Benson et al. (2014) and SpinoInWonderland's measurements, respectively. The fibula MCF-PVPH-108.202 is 101 cm by his measurement, and there are also 2 tibiae (MCF-PVPH-108.68 and 108.73, at 104 and 107.5 cm respectively) and the pubis MCF-PVPH-108.145, which as I have went over earlier in this thread is 110% the size of that in MUCPv-Ch1. There are also several assorted elements (eg: MCF-PVPH-108.169) that suggest a similarly sized animal to MUCPv-Ch1. Assorted elements: The maxilla MCF-PVPH-108.169, the scapular shaft MCF-PVPH-108.185, and the axis MCF-PVPH-108.83 are all stated by Coria and Currie (2006) to be comparable in size to those bones in MUCPv-Ch1, therefore these individuals were most likely around 12.4 meters and 8320 kg or not far from that. Although data is lacking on an average size for G. roseae, the authors did state many of the specimens in the bonebed to be similarly sized to MUCPv-Ch1, so perhaps that can be used as a tentative average for the known possible adults. Fibula: The fibula MCF-PVPH-108.202 is longer than that of MUCPv-Ch1, but SpinoInWonderland suggests because it is more gracile it belongs to a similarly sized, longer legged specimen. So this would be a specimen of about the same size as the assorted elements above. Tibiae: For MCF-PVPH-108.68, applying the discrepancy between MCF-PVPH-108.202 and MUCPv-Ch1 (to account for longer legs) results in a size of of 12.7 meters and 8950 kg. Likewise, this equates to some 13.2 meters and 9880 kg for MCF-PVPH-108.73. So these 2 tibiae are almost certainly representative of both some of the bonebed's largest specimens and some of the largest theropods ever. Pubic shaft: With the upsizing of MUCPv-Ch1, MCF-PVPH-108.145 gets upsized as well. Assuming relative geometric similarity, MCF-PVPH-108.145 ends up at 13.6-13.7 meters and 11100 kg (8320x1.1^3), the same size as my estimate for MUCPv-95. (And for those of you who ask, note that SpinoInWonderland suggests if this specimen simply has an atypically robust pubis, it would probably be the same animal as MCF-PVPH-108.73. Were that the case, it would not be as large as direct isometry suggests but still absolutely gargantuan, substantially bigger than popular estimates). Granted, making these >13 meter estimates for G. roseae hasn't come without its fair share of disagreement from others. Primary sources of disagreement from those people tend to be the following: the estimates being considerably larger than that of Franoys', the estimates being considerably larger than the published literature's maximum estimates that range from 10.2 to 12.7 meters as well as the weights proposed with those estimates, and the specimens in question estimated at >13 meters being fragmentary and not concrete, so the sizes they yield are untenable and should be rejected with what we have now. In that order, here is why my estimates here still stand in the face of all those. My estimates compared to Franoys' estimates: -Franoys assumes that MCF-PVPH-108.145 is simply a MUCPv-Ch1 sized individual with a robust pubis. They have even given an explanation for why they did so in the comments of here (date of April 7, 2018), which is often cited by these people who believe my estimate to be wrong due to its size. (Note that in their explanation are a few statements irrelevant to what I'm looking to demonstrate. They will be the ones that aren't addressed in quote boxes). Quote: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. Let's break it down, shall we? Quote: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). Unless Franoys can give any evidence to the contrary, I am strongly inclined to trust the 10% wider figure over absolutely anything else. There is absolutely zero reason to believe this wasn't an apples to apples measurement concerning the same part of MUCPv-Ch1's pubis. Quote: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 problem here is that there is literally nothing indicating that this is more likely to be the case than the pubic shaft belonging to its own animal 10% larger linearly than MUCPv-Ch1, and it therefore has zero base to be assumed over a standalone MCF-PVPH-108.145 (which does have a base to assume, that being its larger size than other elements). But as stated before, even if we assume out of nowhere that this is the case, the most likely individual (as per what SpinoInWonderland has told me) for it to belong to would be MCF-PVPH-108.73. This animal still appears to be substantially larger in both length and weight than Franoys' size estimate, so it's no argument against G. roseae reaching these >13 meter sizes and very large weights. Quote: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. Frankly, this is quite a poor argument. In a group of animals, there is usually going to be size variation that's notably different to the homogeny that Franoys is assuming (don't believe me? Look, for example, at wolf packs or deer herds, this level of size homogeny is nonexistent within them), and there's absolutely no evidence that this size variation within groups did not exist in G. roseae, while the varying measurements of the bones are suggestive that it did indeed exist, as would be expected. So Franoys' suggestion that the amount of MUCPv-Ch1-sized individuals supports MCF-PVPH-108.145 being one of them just doesn't work, owing to the lack of support for it from both other animals and the fossils themselves. There is no evidence of variation between Giganotosaurus species leading to an animal with a robust pubis instead of a giant that only preserves the pubis either. In fact, not only is there no evidence for any variation between the 2 Giganotosaurus species significant enough to skew my size estimates downward, there's no evidence that said variation (if it existed) excludes MCF-PVPH-108.145 having a proportionally smaller pubis and thus being even larger than isometry from MUCPv-Ch1 suggests. I'm not suggesting this to have been the case, but there is really nothing suggesting it's any less likely than Franoys' proposal (after all, it cannot simply be assumed a priori that species variation skews dinosaur size downwards). Therefore, given that the varying measurements in the specimens suggests this size variation from MUCPv-Ch1 to have been present and give no evidence for variation between species that skews the estimates downward, all data strongly supports MCF-PVPH-108.145 being its own and very large individual, larger than both MUCPv-Ch1 and Franoys' estimate. Quote: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) With all due respect, this statement couldn't be more incorrect. Franoys implies that a 10% larger pubis on a MUCPv-Ch1-sized animal is a generous scenario, but it's actually unrealistically minimalistic in light of the lack of evidence for MCF-PVPH-108.145 to belong to a robust-pubed animal. The scenario most likely to be correct from known data - which is so because no extra assumptions are made beyond what the fossils suggest - is that MCF-PVPH-108.145 is an animal 10% larger linearly and 1/3 more massive than MUCPv-Ch1, with a true generously assumed scenario being that MCF-PVPH-108.145 was an animal more than 10% larger but with a pubis that is smaller relative to the animal's size. Quote: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. As stated before, there is absolutely no reason to do or assume any of this over MCF-PVPH-108.145 being its own, giant individual given known data. Unless Franoys would happen to have any, MCF-PVPH-108.145 completely lacks any evidence that its massive size is the result of geological distortion, variation between species, or being a robust-pubed, smaller specimen. Especially considering that (as also stated before) this geological distortion and variation - if it existed - could well make MCF-PVPH-108.145 represent an animal more than 10% larger than MUCPv-Ch1. Quote:(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) 12.2 meters as a maximum size for G. roseae is directly contradicted by the actual measurements in Coria & Currie (2006), as the paragraphs with the estimates explain. While I do agree with them on a maximum size equal to that of G. carolinii (seeing as how both MUCPv-95 and MCF-PVPH-108.145 are 10% larger than MUCPv-Ch1 and thus indicate 13.7 meters as a plausible maximum for known specimens of both), there is absolutely no way that I know of to get 12.2 meters as an overall maximum with what's published in regards to measurements. In addition, as can be seen by its not being listed in their estimate, Franoys does not take into account MCF-PVPH-108.73. Why this is I do not know, but as can be seen above, taking it into account results in an animal substantially greater in both length and weight than their estimate. My estimates compared to the published literature's estimates between 10.2 and 12.7 meter estimates accompanied with much lower weights: I will deal with 4 estimates here: that for the largest specimen estimated in Coria & Currie (2006), that from Greg Paul, that from Thomas Holtz, and that from Ruben Molina-Perez/Asier Larramendi, in that order. These are most often cited as evidence for my estimates being inaccurate and excessive. -Coria & Currie (2006) estimate a length of 10.2 meters and a weight of 3000 kg for some femora, although these aren't for the same individual. (Side note: even though several of the femora are stated to be adult, no reasoning or justification is given for this. I therefore would consider the age of these specimens, just as with all the bonebed's medium-large individuals, to be unknown unless reasoning is published). As they wrote on pages 103 and 116 respectively, these are the methods behind their weight and length estimates: Quote:The largest of these (MCF-PVPH-108.234) is 1300 mm long, with a shaft circumference of 455 cm. Using the formula developed by Anderson et al. (1985), a conservative weight estimate for this individual would have been 3000 kg. Quote:Estimated lengths (in mm) of animals represented in the Mapusaurus n. gen. bonebed. Calculations based on the relationship between femur length and body length for theropods in which both these values are known (equation is y = 1.0276x + 0.8437, where y is the logarithm of complete body length and x is the logarithm of femur length). Because of the diversity of theropod body forms, these calculations can only be considered as very rough estimates. The problem with the first estimate is that it's based on femur circumference. SpinoInWonderland has written a very good post on his blog about why femur circumference is a very poor choice to estimate size from, and one of his examples (the related Acrocanthosaurus) is actually a fairly useful proxy here - more on that later. Even publications that use femoral circumference (such as the paper on Scotty the T. rex that SpinoInWonderland rightfully condemned) note some animals it really fails on. Interestingly, Acrocanthosaurus is used as an example here as well. Quote:Greater femoral circumference with the capacity to withstand greater locomotor loads, rather than simply greater body mass, merits consideration as an explanation for the discrepancies between femoral lengths and girths in T. rex and G. carolinii. Relative locomotor activity may similarly explain the extreme discrepancies in weight estimations reported for the proportionately slim-femured carcharodontosaurid Acrocanthosaurus atokensis. Notably the 3.5 tonnes femur derived estimation for mass versus 5.5-7 tonnes based on volumetric estimation (Bates et al., 2009). And just as one would expect by what happened with Acrocanthosaurus, this method looks to have failed on G. roseae as well - a volumetric estimate based on MUCPv-Ch1 is considerably larger. MUCPv-Ch1 has a femoral length between 135 cm (page 6) and 136 cm (page 233), that I'll take the mean of, from which we get >7340 kg instead of 3000 kg for the 130 cm G. roseae femur based on my estimate for it (135.5/130(>8320)^3). In addition, this is pleasingly close to the 'correction factor' from femur circumference to volumetric estimates in Acrocanthosaurus - as noted in SpinoInWonderland's blogpost, the Anderson et al. (1985) equations gave 2400 kg to NCSM 14345 compared to the 6177 kg 'best estimate' in Bates et al. As for the 10.2 meter estimate from the length equation, unless any measurements are given for the femur from which it came, it's impossible to verify. But I recommend taking it with a very large grain of salt because measured specimens that have had the equation applied to them are much larger than the equation would suggest when going by the measurements. The length equation gives 8.8 meters for MCF-PVPH-108.202 (a specimen which I estimate at 12.4 meters with published measurements) and 9.8 meters for MCF-PVPH-108.68 (a specimen which I estimate at 12.7 meters with published measurements), so it's likely it's underestimating the femur as well. And the authors even note that the estimates are nothing more than very rough, which certainly doesn't lend credence to said often-cited 10.2 meter maximum. -Greg Paul estimates a maximum length of 11.5 meters, accompanied with a weight estimate of only 5000 kg. I don't know what specimen on which this was based, but it clearly isn't realistic for either of the specimens I estimated at >13 meters, seeing as how both of them are larger than the probably 12.4 meter and >8300 kg MUCPv-Ch1. -Thomas Holtz estimates a maximum length of 12.6 meters (although with no weight estimate). Granted, 12.6 meters does not seem at all unreasonable for some specimens - for one, it's very, very close to my 12.7 meter estimate for MCF-PVPH-108.68. However, there is absolutely zero reason I am aware of to prefer 12.6 meters over 13.7 meters (as well as 13.2 meters) for the larger specimens, seeing as how there is nothing about either those specimens indicating 12.6 meters is more likely than something in the 13-meter range. So with that lack of reason to prefer it over the aforementioned larger sizes, the 12.6 meter maximum estimate is quite unfounded. -Ruben Molina-Perez/Asier Larramendi estimate a maximum length of 12.7 meters and a weight of 7600 kg. Just as I wrote concerning the estimate from Holtz, this length estimate appears more or less on point for some specimens (ie: it matches exactly my estimate for MCF-PVPH-108.68). As a maximum length estimate, however, it doesn't really seem so. There's nothing I'm aware of concerning MCF-PVPH-108.73 and MCF-PVPH-108.145 that suggests an MUCPv-Ch1 based estimate would yield 12.7 meters instead of 13.2-13.7 meters, so given that the sizes of those specimens support nothing but the >13 meter sizes, it's by far the most likely that that's how big they were. The weight estimate is also suspect - 7600 kg as an absolute maximum is even somewhat lower than my estimate for the average of the possible adult specimens, and over 3500 kg smaller than my estimate for the maximum. What the estimate was derived from I do not know, but I strongly trust my own and much larger estimates given that I can actually reach them with the most current data. There's also one last point applying to all the literature's length and weight estimates that's been partially stated above but probably is best reiterated as an all-encompassing statement: Just because these estimates are in the literature, but my 13.2-13.7 meter, 9880-11100 kg estimates are not, is not a valid reason to prefer the former. At all. The published measurements for the bones themselves are exactly what all of my estimates for the largest G. roseae are based on, and those measurements offer zero support to the 10.2-12.7 meter, 3000-7600 kg maximum. Thus, it's very baseless and unparsimonious to take them as a maximum over my estimates just because they are in the literature. My estimates for >13 meter specimens being not concrete and based on fragments, so they should be discarded for the time being: -While it's true that the specimens are fragmentary and the estimates aren't set in stone, that is no reason to treat these specimens as if they simply did not exist. One person on Quora has said the following (admittedly it deals with the pubic shaft and not the tibia), which nicely represents the overall premise of this point when people who disagree with me voice their disagreement: Quote:The really big size estimates for this animal stem from a big pubic shaft. The big problem however basing this idea on a fragment of the pubic shaft is just not reliable at all. The section of pubic shaft that's 10% thicker but that's it, we don't even have the pubis length. You simply cannot extrapolate an (unusually) large size estimate for a multi-tonne animal, reliably from a fragment measuring merely centimeters. Once there is some concrete evidence that shows Mapusauruus or any big fully terrestrial theropod does actually reach over 13 meters long I will update my work accordingly. But so far there really is nothing concrete. Despite the resulting sizes having to be treated as nothing more than estimates due to the fragmentary nature of the specimens, if they indicate a really big size and there is nothing indicating against said size (as in this case), said size should be assumed even as a simple estimate. In a very similar case to what I noted on Franoys' remarks, it is unparsimonious to assume otherwise. The case to use MCF-PVPH-108.73 instead of discard it is even stronger, as it is a weight-bearing tibia and thus quite reliable to estimate size. Basically, it is fallacious to discard the sizes due to the fragmentary bones because there is no evidence to the contrary of those sizes and Occam's razor is therefore contradicted by doing so. On a final note, massive as they are, all these estimates for both G. carolinii and G. roseae are still very likely underestimated. This is because they use Scott Hartman's Giganotosaurus dorsal view, which probably has a ribcage about 9.9% too narrow. __________________________________________________________________________________________________________________________________________________________ Long story short, it seems there's a good chance that these animals were substantially larger than we'd expect! |
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