Continuity mistake: When the T-rex is attacking the kids in the car, in the shot where it stands on top of the car, the metal begins to buckle in the next shot inside the car. When it starts to sink, the metal isn't buckled and you can see the car sinking into the mud pit.
Revealing mistake: The T-rex does not leave or make any footprints in the soft mud during the attack on the car.
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.
Continuity mistake: When the car with Timmy in it falls down the wall, it lands in a tree flat again the concrete wall. Yet later when Alan is rescuing Tim, this is no wall to be seen anywhere. Only other nearby trees.
Visible crew/equipment: Just before the Raptors enter the kitchen,there is a reflection of the camera crew on the door.
Factual error: When the goat leg falls down onto the glass roof of the tour vehicle, the wound on it is much too clean. Whether it is actual meat, it looks like it was cut with a knife. Dinosaurs, like crocodiles had conical teeth and had to tear or rip their prey apart - unlike cats or dogs, whose premolars act in a scissor-like way and actually cut the meat. The wound surface should be frayed and messy. Also, a T-Rex wouldn't even be able to tear apart a goat, because it's too small to step on it and tear at it at the same time. Instead, he would chew and shake it a few times to shatter the bones, then swallow it whole.
Continuity mistake: When the tyrannosaurus is crushing the upside down Landcruiser and mud begins to flow in through the side shattered windows, Lex and Tim are already completely muddy all the way from the tops of their heads, possibly from previous takes.
Continuity mistake: When Muldoon and Hammond are talking about the tropical storm the first time we see a shot of Nedry's workstation behind them and there's hardly anything on the floor, but a few minutes later when Hammond says their lives are in Nedry's hands suddenly the floor is covered in trash.
Continuity mistake: Right after the "Objects in mirror are closer than they appear" shot, the dinosaur breaks a huge trunk that falls forward. A shot later note behind the dinosaur and the huge trunk is nowhere to be seen.
Revealing mistake: When Tim gets electrocuted and falls back from the fence, look closely when he reaches Grant and you will see a red stunt crane in the background.
Continuity mistake: When Ellie runs away from Muldoon towards the Power Station, she climbs over a tree and watches a path in front with two more fallen trees on the way. When she is about to jump over the first one some branches suddenly appear on the close-up to help her do the jump. Furthermore, when she is about jump over the second tree the close-up is a repetition of the previous tree.
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".
Continuity mistake: When the T-rex is attacking the vehicle with the kids inside, Alan gets out of the other car. Even though it is pouring rain and Alan is standing perfectly still, no raindrops are seen hitting his solid, medium-colored shirt. It stays perfectly dry, even though there is nothing overhead that is shielding him from the rain. It is only after the scene cuts to him at the other car that the shirt is suddenly drenched. The rain is obviously CGI.
Continuity mistake: In the scene when Ellie is in the bunker trying to escape from the raptor, she stumbles along the floor gratings and is dragging her flashlight connected to an ankle bracelet. It appears securely connected as indicated by wildly bouncing and being flung around. She bashes her way through the door and slams it behind her, then she runs, suddenly free of the flashlight and connecting strap. If it was as securely attached as shown, she should have had a devastating fall when it was caught in the door, and the raptor would have won.
Factual error: At the beginning of the film we are shown an amber mine in the Dominican Republic. This amber is only 45 million years old, Hammond would never bother buying the amber from there as dinosaurs disappeared from the fossil record 65 million years ago.
Suggested correction: This is assuming that Hammond would restrict himself to a specific period of the earth's history, which makes no sense. Of course Hammond would also be interested in Paleogene or early Tertiary fossil blood! All the proto-birds, giant birds (just think about a Gastornis! What a sensation in a zoo!), not to mention giant mammals like the Megatherion, proto-elephants, proto-rhinoceroses.
There is absolutely no suggestion in Jurassic Park - film or book - that Hammond has any interest in any animals except for dinosaurs. We see no facilities for cloning extinct birds or mammals, nor are they mentioned in his promotional film. The post is correct.
It's specifically mentioned in the book that Hammond was buying huge quantities of amber, even museum-quality jewelry. He was likely getting hold of everything he possibly could to increase chances of finding blood-carrying insects.
There is also absolutely no suggestion that he wouldn't be interested. Surely these would make excellent alternatives / backups in the event he couldn't source enough mosquitos of the era he was most interested in.
As has been pointed out on this site before, inventing deux ex machina explanations for plot holes and factual errors does not invalidate them. Cloning non-egg laying mammals would require vastly different technology to that seen in Jurassic Park. Nowhere in the film is it indicated that Hammond is interested in anything except dinosaurs, nor that he is in any way equipped to clone anything but them.
Hammond buying up any mosquito-containing amber is not a plot hole. He didn't say he wanted exhibits from 45 million years ago, but he also didn't specifically say he wasn't interested. Lack of a statement in a film is not a plot hole.
Continuity mistake: When Grant shoots at the window in the control room, and we see the holes, they are holes from rifle bullets. But the shell casings on the floor is from a shotgun. And yes - shotgun shells do exist with one big slug in them, but then the holes in the glass would be a lot bigger.
Continuity mistake: After Nedry has sprayed the shaving cream on his hands, (and after placing it on the pie) we see a sideview shot where he lowers his hands to his sides. The shot changes to the front and his hands are up again, drying his hands off with a napkin. It was too fast to move his hands.
Continuity mistake: When Alan and the others are with the sick triceratops the sun changes between shots.
Revealing mistake: When the baby dino is hatching you can see light from a hole below the egg. This allowed them to push the fake dino through the fake egg shell.
Continuity mistake: When the five characters start to leave the helicopter upon arrival on the island, Richard Attenborough is not sitting opposite Jeff Goldblum as he was moments earlier as the helicopter descended to the pad.
Suggested correction: Perhaps he just wanted to exit the helicopter first, so he switched places when the helicopter had touched down. You can see they had already undone their seatbelts, so they had time to move around before the door opened.
