Other mistake: Hammond has a pronounced Scottish accent at the start of the film, which deteriorates markedly in just a couple of scenes. By the end of the film he has an upper class English accent. (00:09:50)
Other mistake: When Alan, Lex and Tim are climbing over the perimeter fence and the buzzer begins to sound, Alan and Lex have come off the fence on the other side and Tim loses his footing further up on the fence. He begins to pull himself up, but in the very next shot, a person is seen coming down the fence closer to the ground in khaki shorts and boots. Tim hasn't moved from his position further up, so it can't be him, and Alan and Lex were already on the ground, and did not have khaki shorts on. (00:43:15)
Other mistake: When Grant and the children are up in the tree, as Tim is telling his jokes the camera pans out and we get a wider view. In this shot you can see that Grant's boots are spotlessly clean, which is highly unlikely given the muddy ground, wet environment and his activities over the past few hours. (01:20:35)
Other mistake: When Dr Grant and the children reach the perimeter fence, Dr Grant tries to see if he can fit through, to no avail. When he and the kids start to climb, however, it is quite obvious that both Tim and Lex would have been able to crawl through quite easily, and that only Dr Grant should have had to climb over. Partly this links to the mistake here, where the holes in the fence are much bigger in the first shot, then when he tries to widen them he's holding a different part of the fence where they're smaller.
Other mistake: When Timmy is climbing down the electric perimeter fence, Dr.Grant tells him to jump so he will catch him, it then cuts to another shot where Grant counts down and he isn't remotely anywhere near the fence. He couldn't possibly catch Timmy.
Other mistake: Ray is trying to access the main server and mouths what he types: "access main program", "access main security", "access main program grid". However the text onscreen reads "access security", "access security grid" and "access main security grid".
Other mistake: While being chased by a T-Rex, after it breaks a trunk the digital dinosaur runs behind the car. There's a couple of shots of the people in the moving car and the next time we see the dinosaur angle the background clip is the very same one used before.
Other mistake: The kid who at the dig site in Montana says "That doesn't look very scary" is so far from the screen and behind all the other spectators that he can't possibly see the picture on the screen. And even if he could, it doesn't look anything like a six foot turkey.
Chosen answer: They all left on the same boat Nedry was trying to get on with the embryos. You can hear Samuel L Jackson's character announce that the boat will be leaving at a specific time and everyone had to be there or be left behind.
Shannon Jackson