10. Lake Placid: A crocodile that can bite your leg off is bad enough, but a giant crocodile that can snap you in half is much, much worse.
9. Anaconda: This animal is scary enough in real life, measuring at more than 22 feet long and able to swim at high speeds. An anaconda that has a taste for human flesh and kills without warning? That's much scarier.
8. Piranha: Nothing can ruin a summer day relaxing on the lake worse than a swarm of mutant, man-eating piranhas! One, you might have a chance of fighting off. But an entire swarm? You're doomed.
7. Pet Semetary: A beloved feline is brought back from the dead by a well-meaning father. As much as every parent has wanted to do this to spare their children the sorrow of a dead pet, we see why it's not a good idea. Though the cat only kills birds and mice, he is the foreshadowing of something much more sinister.
6. Congo: Everyone would be scared to run into a gorilla in a jungle. After all, they're large and can take you out with one swipe if they wanted to. But add killer instincts to that, and you have some VERY scary primates!
5. Cujo: A pet Saint Bernard goes from Fido to man eater on a killing spree after he gets rabies, and terrorizes a town (and traps his owners in their car). Man's best friend? We don't think so.
4.The Birds: One of the earliest examples of "man versus nature" films, this Alfred Hitchcock classic turned seemingly innocent animals into mass murderers. The flapping of wings has never sounded so scary. Admit it: Even now, when you see any large gathering of birds, you get a bit spooked out.
3. Jurassic Park: OK, so technically dinosaurs aren't animals but they were at one time and we think they fit in with the list. After seeing the T-Rex going after the car, or the raptors hunting the kids in the kitchen, who didn't pause to give thanks that dinosaurs are extinct?
2. Arachnophobia: How many of you had trouble sleeping the night after watching this movie because you kept feeling spiders crawling up your legs? This movie makes us look at every little spider as a serious threat.
1. Jaws: It's the movie that made an entire generation of movie-goers afraid to go into the water. The shark is "Jaws" is a hunter, a relentless killing machine and he's not afraid to get close to the shore for his next meal.
