Continuity mistake: When Tim and Lex first arrive, Lex is wearing a purple tank top with a colorful design, and in the following scenes or even between consecutive shots her tank top changes to completely different designs, though it's the same style of tank top.
Continuity mistake: After the T. Rex rolls Explorer 4 upside-down with Lex and Tim inside, in the closeup when the dinosaur bites on the rubber tire we see the hub hole at the center of the wheel rim, but two shots later the wheel cover is back on the wheel.
Continuity mistake: While Lex and Tim are hiding in the kitchen, when the large serving spoon falls it cuts to the closeup of the two Velociraptors and the tall shelving unit has vanished, but in the next shot when the one of the raptors leaps onto the counter that tall shelving unit is back.
Continuity mistake: Just before the Tyrannosaurus Rex escapes from its pen, it drops a goat's leg on Lex and Timmy's car. When it comes back to attack them, the leg is gone. Then it appears and disappears. (01:00:25)
Continuity mistake: When the tour trucks are stopped outside the Tyrannosaurus Rex paddock, we are shown a goat in a cage (inside the paddock) that appears to be at the same level as the road (outside). However, when Dr. Grant and Lex go over the wall, the ground is several stories down. (01:06:10)
Continuity mistake: When Lex and Tim are in the car and the T-rex is attacking them, at one point the T-rex smashes through the roof of the car and the clear roof falls through on top of Lex and Tim. The T-rex breaks it with her teeth, but in the next shot it's whole again. (01:03:20)
Continuity mistake: When the lawyer jumps out of the Explorer (just before the T-Rex approaches) he leaves the Explorer door open. In the next two shots the jeep door is closed, but when the T-Rex shows up, the boy moves to the door and closes it. (01:01:40)
Continuity mistake: Take note when the vehicle starts chasing Sam Neill and the kid down the tree. When it first starts to fall, it smashes a headlight and damages a foglight. In the next shot both lights are undamaged and operational. (01:14:20)
Continuity mistake: After Gennaro runs off to hide in the restroom there's a shot of the fence cables ripping apart, and in the following shot of the back of one of the Explorers note that it's missing its black roof vent (and rear wiper), but in following shots of Explorers 4 and 5 the vents are intact on both vehicles. Then just as the T. Rex starts pushing Explorer 4 upside-down its roof vent is gone (presumably, the vehicle missing the vent is a stunt vehicle).
Continuity mistake: When Ellie and Muldoon rescue Ian they leave him in Jeep 10 while they go looking for Alan and the kids, and after the closeup of the water filled T. Rex footprint showing an impact tremor, the next shot zooms in on Ian and we can see the driver's side-view mirror has no writing on it. When they're being chased by the T. Rex, in the shots from behind the Jeep we can see that both side-view mirrors have writing at the top and bottom (shown in closeup "objects in mirror are closer than they appear").
Continuity mistake: When Alan and the kids are about to climb the fence, when he throws a stick at the fence, his hair is messed up, it is sunny and windy. In the next scene his hair is perfectly fixed and it is shady, and it is not windy. (01:36:10)
Continuity mistake: At the badlands, when Hammond's chopper has landed and Grant goes to the trailer to open the door, if you watch the hinges of the door, they're on one side then it cuts to the inside of the trailer and the hinges are on the other side. (00:09:45)
Continuity mistake: While Lex and Tim are hiding in the kitchen, just as the Velociraptors come in Lex tells Tim to follow her, and when they turn into the aisle there's a stainless prep unit with no open shelves right beside them at the end of that aisle, but after the closeups of the Raptor's claws, when the kids continue to crawl away that prep unit has oddly vanished - the last unit in that aisle has shelves, and then it reappears when Tim sits under the utensils.
Continuity mistake: When both Explorer vehicles are parked at the paddock, in the shot of the goat being raised to lure the T. Rex, the "No! Feeding..." sign is permanently affixed to the front of the concrete wall, but in the previous and following shots that same sign is affixed to the angled top part of the wall. Later, when the power goes out, that sign is once again affixed to the front of the concrete wall.
Continuity mistake: When the baby dinosaur is born, one minute the robotic hand is there behind the egg as it's hatching, then in the reverse angle the hand's suddenly disappeared. (00:27:30)
Continuity mistake: After Ellie injures her foot running from the raptor, her limp switches legs repeatedly for the rest of the film. (01:40:10)
Continuity mistake: After Hammond's chopper lands causing winds at the dig site in the badlands, when Alan opens the trailer door the rock hammer is hanging from his belt, but in the interior shot as he walks in the rock hammer has vanished.
Continuity mistake: When the helicopter first lands on the island it is clearly not on the cross on the landing pad. Later in the scene it is. (00:17:25)
Continuity mistake: After Dennis has stolen the embryos, when he reaches the first gate he gets out of the Jeep then uses the manual override to unlock the gate, and in the exterior shot when Dennis walks back to the Jeep his door is wide open, but in the next interior shot his door's closed and he even has difficulty opening it.
Continuity mistake: In the scene with the T. Rex breaking through the glass roof, as the glass breaks one of the rex's front teeth breaks off and flies backward. On the next close-up of the dinosaur's mouth, the tooth is still missing, yet it is back in all shots after that.
Answer: They are not paleontologists, just people interested in dinosaurs. It is common for museums and other scientific organizations to offer the general public an opportunity to participate in a real paleontology dig. For a fee, they become an exhibition team member for a period of time, learn about dinosaurs, help excavate fossils, and so on. This is likely how Dr. Grant (or his institution) supplements his research funding.
raywest ★