| Mr. Holtz.... Thanks for taking the time to respond and for telling me that I'm at least on track with my simple observations.... And definitely thanks for that abstract of yours....
"Biomechanical analyses suggest such this plan is effective at vertical slicing, but is poorly resistant to torsional forces"........That is really obvious.... Tyrannosaurus rex fought with prey..... It was a - rush out and bite the sucker hard and fast as the prey was running away at a good clip - type of thing... Which also goes toward the evolution of the elevated bite strength to begin with.... One hard, crippling blow so the predator didn't have to keep chasing after the prey, having to hit it again..... Less contact between the two the better... Less chance of injury to the predator... In fact, the entire build of tyrannosaurs in general sheds light on that type of predation scenario. Giganotosaurus didn't have to worry about any of this... Hence, why it evolved to be built as it was built... In fact, as was pointed out, the same type of build is pretty much present in all the carnosaurs.... and they all were going after the same type of prey and thus! t! ! he same type of predation scenario..... This makes me wonder about that nibbling idea that Paul brought up in his 1998 "Terramegathermy And Cope's Rule In The Land Of Titans" paper. Tyrannosaurs on the other hand?..... An entirely different ball game..... Like you said.... The Zoological aspects are so important. No ossified secondary palate.... "labiolingually expanded (incrassate) teeth, and well developed ossified secondary palates composed of medial extensions of the premaxillae and maxillae and a large..."... Once again, right on the money.... There was even a test I just read about with an opossum. They removed its secondary palate and the animal lost a great deal of its biting ability. Since the second palate also acts as another brace when you really need strength in the front of the skull while biting, etc etc..... No further explanation is needed. It goes right back to what was said above. "Further support for a torsion-based feeding system in tyrannosaurs is indicated by the expansion of the posterior portion of the skull, increasing neck muscle leverage"...... Absolutely..... It's spectacular actually...... And it's scary to think what that means about the power involved.... Bite... pull...... oh boy..... But I do have a question.... One that I was toying with in my posts... Why did Giganotosaurus have such a wide back of the neck???.... especially when nothing else seemed to point towards an ability to take the force of torsion??? That entire last paragraph of yours completely explains why Tyrannosaurus rex could pull side to side and why this was not as easy for the more basal builds.... Basically the back of the jaw did not get in the way for Tyrannosaurus rex. But, it does in the others, though that is just the result in how they are built....You can see they had limited motion in their necks to begin with... This was what I was playing around with when I mentioned ideas as to why this was the case in Giganotosaurus and what it could mean toward predator-prey interactions and whatnot. All I can say is that from what you wrote back, it is good to know the same sort of things are of interest to you. Kris |