One thing I always wondered about the original film: How did Alan Grant know so much about dinosaur behavior? How did he know that a T-Rex can't see you if you don't move? (And if the T-Rex has such a great sense of smell, as we were told in The Lost World, why is it so dependent on vision to catch its prey?) How did he know that raptors are not only pack hunters but that they specifically try to distract you with the raptor in front of you while another raptor comes in from the side and kills you?
There's a lot of stuff scientists can tell from bone/fossil collection. It's likely Grant followed the similarities he saw between the dinosaur skeletons and modern-day bird skeletons and extrapolated from there on dinosaur behavior. Which is more-or-less how scientists today do it.
There's also other ways to tell, I suspect, including whether or not you find similar dinosaurs grouped together in a "grave site" or a lone skeleton. The grouped ones suggesting they traveled, and then likely worked together, in packs.
On the vision thing that's a heck of a lot tougher since there'd pretty much no way to know this. Again, maybe extrapolating from similar animals, judging what the size of the T-Rex's brain likely would have been and where it's eyes were located. But all of this contrasts with present-day extrapolations saying that the position of the T-Rex's eyes likely gave it binocular vision.
The concept that it couldn't see you if you didn't move, in the novel, also was an added "feature" InGen gave the T-Rex in order to make it slightly safer to keep in the park. (IIRC this was the case.)
But there's little reason for this to make sense and obviously the T-Rex would be able to *see* things that couldn't move (that's be a pretty shitty way for eyes to evolve and would make navigating the world pretty damn hard) it'd probably be more accurate to say it wouldn't regard things if it didn't move or needed them to move in some circumstances in order to see them around it's mouth/beak. So "don't move" was less "he won't see us" and more "it'll be harder for him to see us and less a chance for him to regard us as a source of food."
Obviously at one point the T-Rex knew there was a source of food in the Explorer which is why he yelled at it and attacked it. Lex and Tim didn't have to move after a certain point to be "seen" because the cat was already out of the bag.
When the the Rex noses at Grant and Lex it probably couldn't see well around its own beak and the dampness obscured its ability to smell. It *knew* something was there it couldn't see it, so it moved the car and pawed at things to make something happen.
We see similar things happen in TLW where the Rexes move and attack things based on knowledge they have, not because things are moving.
But there are ways for present-days scientists to extrapolate how extinct creatures likely lived and behaved by studying their remains and living creatures.
One thing I thought was odd was that Grant tries to support his arguments for dinosaurs being birds by saying the word "Raptor" means "bird of prey." Which.... That's not by any choice or evolution on the dinosaur's part, is it? It's just what people opted to name it at some point regardless of what the word meant. How is what the thing is called proof of anything?!
