Dr. Grant's raptor claw is arguably the only true symbol in the movie. It's a fossil that Dr. Grant keeps with him at all times, presumably to taunt children with. When an annoying young boy compares a Velociraptor to a turkey, Grant pulls out his trusty raptor claw—which he describes as sharp "like a razor"—and proceeds to demonstrate how the raptor would gut the kid and eat him. "You are alive when they start to eat you," he says, just in case this whole situation wasn't scary enough.
What's the point of all that? To demonstrate to the kid that he should "try to show a little respect" to an extinct creature. Lesson learned.
Of course, the raptors turn out to be un-extinct, and just as scary as Grant describes them. When Grant finds himself protecting children from dinosaurs instead of using the threat of dinosaurs to intimidate children, he isn't that fond of the raptor claw anymore. Up in the tree with Tim and Lex, Grant sits on the raptor claw. We can't think of anything more uncomfortable than a razor sharp claw in the butt, so it's no wonder Grant pulls it out of his pocket and tosses it away.
So if the claw is a symbol, what's it a symbol of? Has Grant sworn off archaeology because now he knows how terrible these ancient lizards can be? Or is he throwing away his hatred for children and embracing them instead? You'll have to dig up your own interpretation.