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Verdugo
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Oct 9 2012, 02:00 PM
Post #781
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Large Carnivores Enthusiast
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- Fragillimus335
- Oct 9 2012, 12:30 PM
- theropod
- Oct 9 2012, 04:44 AM
that does not mean they don´t have the density of the surrounding material. from my expierience most fossils do seem to have a rather higher density than the stone they are in, and soft tissues just like everything else in a FOSSIL is fossilized. frgaillimus ought to know more about this, I have never had that much interest in geology, but they are certainly not very different from the surrounding minerals in terms of density
Yes, they are quite similar to the rock they fossilize in. No bone has ever been found with significant preserved soft tissue, despite what the media says. Fossil bones often weigh 2 times as much as living bone, and the vey thin walled, pneumatic theropod bones would show an even greater difference. So you meant all Theropod should get 2-3 times lighter, right ?. So Sue would weigh ~ 3-4,5 tonnes ?
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Fragillimus335
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Oct 9 2012, 02:04 PM
Post #782
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- Verdugo
- Oct 9 2012, 02:00 PM
- Fragillimus335
- Oct 9 2012, 12:30 PM
- theropod
- Oct 9 2012, 04:44 AM
that does not mean they don´t have the density of the surrounding material. from my expierience most fossils do seem to have a rather higher density than the stone they are in, and soft tissues just like everything else in a FOSSIL is fossilized. frgaillimus ought to know more about this, I have never had that much interest in geology, but they are certainly not very different from the surrounding minerals in terms of density
Yes, they are quite similar to the rock they fossilize in. No bone has ever been found with significant preserved soft tissue, despite what the media says. Fossil bones often weigh 2 times as much as living bone, and the vey thin walled, pneumatic theropod bones would show an even greater difference.
So you meant all Theropod should get 2-3 times lighter, right ?. So Sue would weigh ~ 3-4,5 tonnes ? Of course not, it is very unlikely giant theropods and human had proportionally similar skeletal weights.... I think the largest tyrannosaurs (like Sue size) weighed 6-7.5 tons, like nearly every other respectable paleontologist.
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Verdugo
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Oct 9 2012, 02:36 PM
Post #783
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Large Carnivores Enthusiast
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- Fragillimus335
- Oct 9 2012, 02:04 PM
- Verdugo
- Oct 9 2012, 02:00 PM
- Fragillimus335
- Oct 9 2012, 12:30 PM
- theropod
- Oct 9 2012, 04:44 AM
that does not mean they don´t have the density of the surrounding material. from my expierience most fossils do seem to have a rather higher density than the stone they are in, and soft tissues just like everything else in a FOSSIL is fossilized. frgaillimus ought to know more about this, I have never had that much interest in geology, but they are certainly not very different from the surrounding minerals in terms of density
Yes, they are quite similar to the rock they fossilize in. No bone has ever been found with significant preserved soft tissue, despite what the media says. Fossil bones often weigh 2 times as much as living bone, and the vey thin walled, pneumatic theropod bones would show an even greater difference.
So you meant all Theropod should get 2-3 times lighter, right ?. So Sue would weigh ~ 3-4,5 tonnes ?
Of course not, it is very unlikely giant theropods and human had proportionally similar skeletal weights.... I think the largest tyrannosaurs (like Sue size) weighed 6-7.5 tons, like nearly every other respectable paleontologist. So you meant despite the look, Theropod would have proportionately lighter skeleton structure than human ?
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SpinoInWonderland
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Oct 9 2012, 03:07 PM
Post #784
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The madness has come back...
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- Verdugo
- Oct 9 2012, 02:36 PM
- Fragillimus335
- Oct 9 2012, 02:04 PM
- Verdugo
- Oct 9 2012, 02:00 PM
- Fragillimus335
- Oct 9 2012, 12:30 PM
- theropod
- Oct 9 2012, 04:44 AM
that does not mean they don´t have the density of the surrounding material. from my expierience most fossils do seem to have a rather higher density than the stone they are in, and soft tissues just like everything else in a FOSSIL is fossilized. frgaillimus ought to know more about this, I have never had that much interest in geology, but they are certainly not very different from the surrounding minerals in terms of density
Yes, they are quite similar to the rock they fossilize in. No bone has ever been found with significant preserved soft tissue, despite what the media says. Fossil bones often weigh 2 times as much as living bone, and the vey thin walled, pneumatic theropod bones would show an even greater difference.
So you meant all Theropod should get 2-3 times lighter, right ?. So Sue would weigh ~ 3-4,5 tonnes ?
Of course not, it is very unlikely giant theropods and human had proportionally similar skeletal weights.... I think the largest tyrannosaurs (like Sue size) weighed 6-7.5 tons, like nearly every other respectable paleontologist.
So you meant despite the look, Theropod would have proportionately lighter skeleton structure than human ? I'm not Fragillimus335 but yes, a theropod would have a proportionally lighter skeleton than a human, because of bone pneumaticity. Dinosaur bones are hollow but strong.
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Verdugo
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Oct 9 2012, 03:34 PM
Post #785
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- brolyeuphyfusion
- Oct 9 2012, 03:07 PM
- Verdugo
- Oct 9 2012, 02:36 PM
- Fragillimus335
- Oct 9 2012, 02:04 PM
- Verdugo
- Oct 9 2012, 02:00 PM
- Fragillimus335
- Oct 9 2012, 12:30 PM
- theropod
- Oct 9 2012, 04:44 AM
that does not mean they don´t have the density of the surrounding material. from my expierience most fossils do seem to have a rather higher density than the stone they are in, and soft tissues just like everything else in a FOSSIL is fossilized. frgaillimus ought to know more about this, I have never had that much interest in geology, but they are certainly not very different from the surrounding minerals in terms of density
Yes, they are quite similar to the rock they fossilize in. No bone has ever been found with significant preserved soft tissue, despite what the media says. Fossil bones often weigh 2 times as much as living bone, and the vey thin walled, pneumatic theropod bones would show an even greater difference.
So you meant all Theropod should get 2-3 times lighter, right ?. So Sue would weigh ~ 3-4,5 tonnes ?
Of course not, it is very unlikely giant theropods and human had proportionally similar skeletal weights.... I think the largest tyrannosaurs (like Sue size) weighed 6-7.5 tons, like nearly every other respectable paleontologist.
So you meant despite the look, Theropod would have proportionately lighter skeleton structure than human ? I'm not Fragillimus335 but yes, a theropod would have a proportionally lighter skeleton than a human, because of bone pneumaticity. Dinosaur bones are hollow but strong. Actually, Theropod bones are denser than mammal bones despite the fact it was hollow. Because bird bones are denser and stronger than mammal bones
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For centuries biologists have known that bird bones are hollow, and even elementary school children know that bird skeletons are lightweight to offset the high energy cost of flying. Nevertheless, many people are surprised to learn that bird skeletons do not actually weigh any less than the skeletons of similarly sized mammals. In other words, the skeleton of a two-ounce songbird weighs just as much as the skeleton of a two-ounce rodent.
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Bird biologists have known this for a long time, but it took a modern bat researcher, Elizabeth Dumont of the University of Massachusetts Amherst, to explain how bird skeletons can look so delicate and still be heavy. The answer is that bird bones are denser than mammal bones, which makes them heavy even though they are thin and sometimes even hollow. Her findings, supported by bone density measurements, are published in the March 17 issue of Proceedings of the Royal Society B. As Dumont explains, "The fact that bird bones are denser than bones in mammals not only makes them heavier for their size, but it may also make them stiffer and stronger. This is a new way to think about how bird skeletons are specialized for flying and solves the riddle of why bird skeletons appear so lightweight and are still relatively heavy. This has never been explained fully and so has never gotten into the textbooks. I'd like to see that change."
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Dumont measured the density of the cranium, the upper arm bone or humerus and the thigh or femur bones in song birds, rodents and bats by measuring bone mass and volume. "I found that, on average, these bones are densest in birds, followed closely by bats. Many other studies have shown that as bone density increases, so do bone stiffness and strength. Maximizing stiffness and strength relative to weight are optimization strategies that are used in the design of strong and stiff but lightweight man-made airframes," she points out. Density is a measure of mass per unit of volume; dense bones are both heavier and stronger, much as a titanium toothpick would be stronger than a wooden one
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Galileo described bird bones as lightweight in 1683, Dumont says. Her new data help to dispel the common misconception that bird skeletons are lightweight relative to body mass. Instead, bird and bat skeletons only appear to be slender and delicate -- because they are dense, they are also heavy. Being dense, strong and stiff is one more way that birds' and bats'
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theropod
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Oct 9 2012, 10:50 PM
Post #786
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palaeontology, open source and survival enthusiast
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That´s interesting, still calculating the weight by using the approximate ratio of skeletal weight to total weight from a hominid is extremely unreliable.
4,5t is the lower end for T. rex that has ever been calculated and everybody agrees about 6-7,5t being the most accepted estimate, as fragillimus already wrote
fun fact: I once saw a childrens documentary that really gave sue a 3t weight due to heigh bone pneumacity. maybe that based on a similarly flawed metodology...
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Fragillimus335
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Oct 10 2012, 12:28 AM
Post #787
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- Verdugo
- Oct 9 2012, 03:34 PM
- brolyeuphyfusion
- Oct 9 2012, 03:07 PM
- Verdugo
- Oct 9 2012, 02:36 PM
- Fragillimus335
- Oct 9 2012, 02:04 PM
- Verdugo
- Oct 9 2012, 02:00 PM
- Fragillimus335
- Oct 9 2012, 12:30 PM
- theropod
- Oct 9 2012, 04:44 AM
that does not mean they don´t have the density of the surrounding material. from my expierience most fossils do seem to have a rather higher density than the stone they are in, and soft tissues just like everything else in a FOSSIL is fossilized. frgaillimus ought to know more about this, I have never had that much interest in geology, but they are certainly not very different from the surrounding minerals in terms of density
Yes, they are quite similar to the rock they fossilize in. No bone has ever been found with significant preserved soft tissue, despite what the media says. Fossil bones often weigh 2 times as much as living bone, and the vey thin walled, pneumatic theropod bones would show an even greater difference.
So you meant all Theropod should get 2-3 times lighter, right ?. So Sue would weigh ~ 3-4,5 tonnes ?
Of course not, it is very unlikely giant theropods and human had proportionally similar skeletal weights.... I think the largest tyrannosaurs (like Sue size) weighed 6-7.5 tons, like nearly every other respectable paleontologist.
So you meant despite the look, Theropod would have proportionately lighter skeleton structure than human ? I'm not Fragillimus335 but yes, a theropod would have a proportionally lighter skeleton than a human, because of bone pneumaticity. Dinosaur bones are hollow but strong.
Actually, Theropod bones are denser than mammal bones despite the fact it was hollow. Because bird bones are denser and stronger than mammal bones - Quote:
-
For centuries biologists have known that bird bones are hollow, and even elementary school children know that bird skeletons are lightweight to offset the high energy cost of flying. Nevertheless, many people are surprised to learn that bird skeletons do not actually weigh any less than the skeletons of similarly sized mammals. In other words, the skeleton of a two-ounce songbird weighs just as much as the skeleton of a two-ounce rodent.
- Quote:
-
Bird biologists have known this for a long time, but it took a modern bat researcher, Elizabeth Dumont of the University of Massachusetts Amherst, to explain how bird skeletons can look so delicate and still be heavy. The answer is that bird bones are denser than mammal bones, which makes them heavy even though they are thin and sometimes even hollow. Her findings, supported by bone density measurements, are published in the March 17 issue of Proceedings of the Royal Society B. As Dumont explains, "The fact that bird bones are denser than bones in mammals not only makes them heavier for their size, but it may also make them stiffer and stronger. This is a new way to think about how bird skeletons are specialized for flying and solves the riddle of why bird skeletons appear so lightweight and are still relatively heavy. This has never been explained fully and so has never gotten into the textbooks. I'd like to see that change."
- Quote:
-
Dumont measured the density of the cranium, the upper arm bone or humerus and the thigh or femur bones in song birds, rodents and bats by measuring bone mass and volume. "I found that, on average, these bones are densest in birds, followed closely by bats. Many other studies have shown that as bone density increases, so do bone stiffness and strength. Maximizing stiffness and strength relative to weight are optimization strategies that are used in the design of strong and stiff but lightweight man-made airframes," she points out. Density is a measure of mass per unit of volume; dense bones are both heavier and stronger, much as a titanium toothpick would be stronger than a wooden one
- Quote:
-
Galileo described bird bones as lightweight in 1683, Dumont says. Her new data help to dispel the common misconception that bird skeletons are lightweight relative to body mass. Instead, bird and bat skeletons only appear to be slender and delicate -- because they are dense, they are also heavy. Being dense, strong and stiff is one more way that birds' and bats'
No, not because of lighter bones, but because of a different skeleton design. Do you really think all animals in the world have proportionately heavy skeletons to a human? And please don't forget that Tyrannosaurus had massive air sacs that would have made it lighter, both in the bones and in the body cavity.
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Fist of the North Shrimp
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Oct 10 2012, 01:02 AM
Post #788
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I think the pneumaticity of the bones themselves has been accounted for in that calculation. BTW, if someone is interested: http://onlinelibrary.wiley.com/doi/10.1111/j.1469-185X.2011.00190.x/full
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theropod
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Oct 10 2012, 03:45 AM
Post #789
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palaeontology, open source and survival enthusiast
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I know the pneumacity has been accounted for, but the point is it affects how heavy fossilized bones are compared to normal ones. The study did undoubtedly take airsacks ect. into account, that is absolutely clear, even tough it uses far too liberal amounts of tissue...
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Fragillimus335
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Oct 10 2012, 04:10 AM
Post #790
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The point is, fossilized bone is heavier than un-fossilized bone....it is an undisputed fact.
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Verdugo
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Oct 10 2012, 02:09 PM
Post #791
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Large Carnivores Enthusiast
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- Fragillimus335
- Oct 10 2012, 12:28 AM
- Verdugo
- Oct 9 2012, 03:34 PM
- brolyeuphyfusion
- Oct 9 2012, 03:07 PM
- Verdugo
- Oct 9 2012, 02:36 PM
- Fragillimus335
- Oct 9 2012, 02:04 PM
- Verdugo
- Oct 9 2012, 02:00 PM
- Fragillimus335
- Oct 9 2012, 12:30 PM
- theropod
- Oct 9 2012, 04:44 AM
that does not mean they don´t have the density of the surrounding material. from my expierience most fossils do seem to have a rather higher density than the stone they are in, and soft tissues just like everything else in a FOSSIL is fossilized. frgaillimus ought to know more about this, I have never had that much interest in geology, but they are certainly not very different from the surrounding minerals in terms of density
Yes, they are quite similar to the rock they fossilize in. No bone has ever been found with significant preserved soft tissue, despite what the media says. Fossil bones often weigh 2 times as much as living bone, and the vey thin walled, pneumatic theropod bones would show an even greater difference.
So you meant all Theropod should get 2-3 times lighter, right ?. So Sue would weigh ~ 3-4,5 tonnes ?
Of course not, it is very unlikely giant theropods and human had proportionally similar skeletal weights.... I think the largest tyrannosaurs (like Sue size) weighed 6-7.5 tons, like nearly every other respectable paleontologist.
So you meant despite the look, Theropod would have proportionately lighter skeleton structure than human ? I'm not Fragillimus335 but yes, a theropod would have a proportionally lighter skeleton than a human, because of bone pneumaticity. Dinosaur bones are hollow but strong.
Actually, Theropod bones are denser than mammal bones despite the fact it was hollow. Because bird bones are denser and stronger than mammal bones - Quote:
-
For centuries biologists have known that bird bones are hollow, and even elementary school children know that bird skeletons are lightweight to offset the high energy cost of flying. Nevertheless, many people are surprised to learn that bird skeletons do not actually weigh any less than the skeletons of similarly sized mammals. In other words, the skeleton of a two-ounce songbird weighs just as much as the skeleton of a two-ounce rodent.
- Quote:
-
Bird biologists have known this for a long time, but it took a modern bat researcher, Elizabeth Dumont of the University of Massachusetts Amherst, to explain how bird skeletons can look so delicate and still be heavy. The answer is that bird bones are denser than mammal bones, which makes them heavy even though they are thin and sometimes even hollow. Her findings, supported by bone density measurements, are published in the March 17 issue of Proceedings of the Royal Society B. As Dumont explains, "The fact that bird bones are denser than bones in mammals not only makes them heavier for their size, but it may also make them stiffer and stronger. This is a new way to think about how bird skeletons are specialized for flying and solves the riddle of why bird skeletons appear so lightweight and are still relatively heavy. This has never been explained fully and so has never gotten into the textbooks. I'd like to see that change."
- Quote:
-
Dumont measured the density of the cranium, the upper arm bone or humerus and the thigh or femur bones in song birds, rodents and bats by measuring bone mass and volume. "I found that, on average, these bones are densest in birds, followed closely by bats. Many other studies have shown that as bone density increases, so do bone stiffness and strength. Maximizing stiffness and strength relative to weight are optimization strategies that are used in the design of strong and stiff but lightweight man-made airframes," she points out. Density is a measure of mass per unit of volume; dense bones are both heavier and stronger, much as a titanium toothpick would be stronger than a wooden one
- Quote:
-
Galileo described bird bones as lightweight in 1683, Dumont says. Her new data help to dispel the common misconception that bird skeletons are lightweight relative to body mass. Instead, bird and bat skeletons only appear to be slender and delicate -- because they are dense, they are also heavy. Being dense, strong and stiff is one more way that birds' and bats'
No, not because of lighter bones, but because of a different skeleton design. Do you really think all animals in the world have proportionately heavy skeletons to a human? And please don't forget that Tyrannosaurus had massive air sacs that would have made it lighter, both in the bones and in the body cavity.
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No, not because of lighter bones, but because of a different skeleton design.
Do you notice this part ?. There's nothing to do with skeleton design here, also this study has proven that bird's skeleton would weigh as much as the skeleton of equal size mammal
- Quote:
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Dumont measured the density of the cranium, the upper arm bone or humerus and the thigh or femur bones in song birds, rodents and bats by measuring bone mass and volume. "I found that, on average, these bones are densest in birds, followed closely by bats.
- Quote:
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And please don't forget that Tyrannosaurus had massive air sacs that would have made it lighter, both in the bones and in the body cavity.
The 9,5 tonnes estimate for Sue has already included the air-sac you know
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Fragillimus335
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Oct 10 2012, 02:40 PM
Post #792
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Yea, but it's grossly obese. It would not have been a powerful hunter at that weight, just a blob.
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Verdugo
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Oct 10 2012, 02:42 PM
Post #793
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- Oct 10 2012, 02:40 PM
Yea, but it's grossly obese. It would not have been a powerful hunter at that weight, just a blob. So your 20+ tonnes Spinosaurus was a sitting duck right ?
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theropod
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Oct 10 2012, 08:45 PM
Post #794
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palaeontology, open source and survival enthusiast
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it was a fish eater, but he is not claiming anythign about a spinosaurus that heavy. and scaled down to T. rex lenght his 18t spinosaurus is only 5,7t...
definitely this is not greossly obese but far too low assuming T. rex was really 9,1t. this T. rex model does still seem too bulky imo, but assuming it was 9,1t other theropods would also be heavier than we tought, which i don´t believe in because they simply are not animals built for stability and weight support and all of them do have a relatively cursorial, slender built
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SpinoInWonderland
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Oct 10 2012, 11:28 PM
Post #795
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The madness has come back...
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- Verdugo
- Oct 10 2012, 02:42 PM
- Fragillimus335
- Oct 10 2012, 02:40 PM
Yea, but it's grossly obese. It would not have been a powerful hunter at that weight, just a blob.
So your 20+ tonnes Spinosaurus was a sitting duck right ? Any theropod at 20 tonnes would collapse. That kind of mass is off-limits for bipedals
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