Correct me if I am wrong, but does the Spinosaur in JP3 have its teeth arranged the wrong way round? I thought the largest teeth were up in front of the snout to aid it in snaring fish. How come the JP3 Spinosaurus looks like it has large maximillinary (wrong spelling I know), teeth in the movie. Also, what's up with the curved teeth of the Spinosaurus, is this accucrate? I though their teeth had virtually no recurvature. On teeth also. What exactly was so special about Tyrannosaurus teeth that allowed them to bite so much harder than any species of dinosaur known, to the point of being capable of biting a chunk out of a Triceratops frill? Did this ability to also rend bone give it an advantage over other predators in terms of attacking other animals? Given that, I think it's likely he could attack a Land Rover or a light Aircraft he he wanted, though I doubt he would have been dumb enough to attack something with too little food value at all. Also as a final question. Are Tyrannosaurids more intelligent and complex compaired to other large carnivores like Giganotosaurus? What advantage did it serve?
from C.E.R.A.T.O, age ?, ?, ?, ?; July 24, 2001

TOM: WHOA! That's a lot of questions!

Okay, step by step:
Yes, the movie version of Spinosaurus didn't quite get the tooth proportions correct. See the figure in the JPI Dinosaur Field Guide for something closer.

Although there is a slight curvature to spinosaurid teeth, they are much closer to straight than your average meat-eating theropod.

Tyrannosaur teeth differ from other theropod teeth in being very thick side-to-side (sometimes as thick or thicker side-to-side than front-to-back in cross-section). Futhermore, they are very deeply rooted: while most theropod teeth are half crown and half root, tyrannosaurid teeth are 1/3 crown and 2/3 root. On top of this, tyrannosaurs had a solid bony roof of the mouth (unlike typical large theropods) and an expanded back of the skull for jaw and neck muscle attachment.

The stronger bite of tyrannosaurs probably gave it a couple of advantages. It could hold onto a victim much longer and stronger than an allosaur, for example. Futhermore, being able to crush bones would allow it to get more food value out of each kill.

I suspect that any theropod (or aggressive plant eater, for that matter) might attack a vehicle if they saw it if their defense involved fighting.

Finally (whew!!), tyrannosaur brains are indeed larger than those of allosaurs (like Allosaurus, Acrocanthosaurus, Giganotosaurus, and Carcharodontosaurus) of the same body size, by almost a 2:1 factor. (Incidentally, this is discounting the olfactory bulbs, which are the smelling centers. Those of tyrannosaurs are immense, but those of the allosaurs have yet to be studied). Tyrannosaurs are members of the Coelurosauria, the most advanced group of meat-eaters, and are descendants of small-bodied, fast running, agile predators. Tyrannosaurids inherited their big brains (relatively speaking) from their little ancestors. It would have been advantageous to the tyrannosaurs in hunting their very advanced and sophisticated prey. Duckbills and horned dinosaurs (the main prey of the tyrannosaurs) were big-brained for plant eaters, may have had more complex herd structures, and were faster and more agile, compared to sauropods and stegosaurs (the main prey of allosaurs).