There's a reason why certain creatures are able to survive and live for millions of years. It's because they're absolutely terrifying, which keeps predators from messing with them. Here are 12 of the oldest animals on the planet, who also happen to be the most terrifying. There's no scientific proof that survival skills increase with terror, but I'm convinced. They have been on Earth far longer than humans, and you'll see why. Watch out for #7; it'll definitely give you nightmares. 1.) Frilled Shark. Pinterest This cross between a shark and an eel is unsettling. The frilled shark was around...