Trivia: The scenes with the flying dinosaurs were supposed to be in the original movie, as it was part of the book Jurassic Park, but Spielberg decided not to include this in the first movie due to budget restraints.
Trivia: Dr. Grant's brown truck with the Museum of the Rockies and Montana State University logos on it is the actual vehicle that belongs to Dr. Jack Horner, paleontologist consultant on the Jurassic Park films as well as the man that the character of Grant is based on.
Trivia: In the bar scene you can see a Jurassic Park pinball machine.
Answer: While the movie doesn't explain this, it most certainly wasn't a dinosaur (since a carnivorous dinosaur would eat him). However, in Jurassic Park Adventures: Survivor, he dies from internal injuries due to the rough "landing".
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