
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.
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