Posted on 02/27/2002 10:29:03 AM PST by RoughDobermann
Edited on 04/29/2004 2:00:10 AM PDT by Jim Robinson. [history]
STANFORD, California (CNN) -- New models of the leg muscles of Tyrannosaurus Rex suggest that a real T-Rex might not have passed the screen test for "Jurassic Park." Stanford University researchers writing in the British journal Nature this week suggest that a T-Rex could not have been able to run as fast as the one in the movie -- and might not have been able to run at all.
(Excerpt) Read more at cnn.com ...
Reading this line, I suspected Medved was afoot. I'm sure he would say that earth's gravity was partially cancelled by Saturn, about which earth revolved.
Thats over 32,000 pounds...
It turns out that gravity is some sort of an electrostatic dipole effect and not a basic force in nature. In prehistoric times, there was more static electricity around the Earth's surface and gravity was attenuated.
You lose power/weight ratio as you get bigger no matter what you do; weight is proportional to volumn, a cubed figure, while strength is generally proportional to cross section of bone and muscle, which is a squared figure. Top human powerlifters reach a mathematical point of no return at about 20,000 lbs. because of this square/cube problem, and no grass-eating herbivore such as a brachiosaurid would be stronger than a top human weightlifter on a per-pound basis.
All prehistoric size limits were significantly greater than they are now. The biggest birds which can take off and land presently are albatrosses and berkuts and what not and those are limited to about 30 lbs. In ancient times, you had teratorns which were a sort of a 200 lb eagle with a 25' wingspan which flew, as well as pterosaurs which were double that size or more.
Fascinating. I've never heard of this. Could you provide some links or sources? I'd like to read up on it.
You are aware that human muscles are only capable of generating 1/10 the force of any other mammal's muscles on a gram per gram basis, aren't you?
Next thing you know, they'll explain how the cow evolved from the pine tree.
No, I'm not aware of that and neither should you be since it is absolutely not true.
For instance, from Knut Nielson's, "Scaling, Why is Animal size So Important", Cambridge Univ Press, 1984, page 163, we have:
"It appears that the maximum force or stress that can be exerted by any muscle is inherent in the structure of the muscle filaments. The maximum force is roughly 4 to 4 kgf/cm2 cross section of muscle (300 - 400 kN/m2). This force is body-size independent and is the same for mouse and elephant muscle. The reason for this uniformity is that the dimensions of the thick and thin muscle filaments, and also the number of cross-bridges between them are the same. In fact the structure of mouse muscle and elephant muscle is so similar that a microscopist would have difficulty identifying them except for a larger number of mitrochondria in the smaller animal. This uniformity in maximum force holds not only for higher vertebrates, but for many other organisms, including at least some, but not all invertebrates."
The simple analysis is that volume increases with the cube of the size (which is roughly proportional to mass, while strength scales with the square of the size. (strength actually refers to structural strength, but it gives you an idea of what happens)
So, the mass/strength ratio varies with the 3/2 power of size.
Then they never saw my ex wife hurling a can of tuna in my direction.
I should change MY mind after posting a totally authoritative source on the topic?? Are the words "truth" or "reality" in your vocabulary or is propaganda and dialectics all you know?
To medved, "ouch!"
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