If we're going to get reductive about plausibility, I think a movie about a shark that eats people and attacks a boat is more plausible than anything you'll find in Jurassic Park. Think about it; a corporation is able to keep secret a group of scientists cloning hundreds of dinosaurs from partial DNA samples and the construction of a massive, hugely expensive theme park -- both of which appear to have been accomplished in a relatively short period of time.
I'm far more interested in in-movie consistency than with plausibility per se
. Pretty much everything about Jurassic Park
is big and outlandish all the way through, so I can roll with it. Jaws
, on the other hand, is fairly low-key, believable and realistic in the first half, with a few swimmers getting munched on here and there, then turns into Terminator On Water!
in its second. An hourlong movie wouldn't have been marketable, granted, but from an artistic standpoint, I'm inclined to think the whole expedition/hunt sequence ought to have been scrapped, or at the very least drastically reduced. In Man vs. Monsters terms, I much prefer Alien
, a rather more internally consistent film.