Slowest sharks in world prey on happily sleeping seals

It's the stuff of nightmares. You're happily dozing with the soothing sounds of the ocean all around you, then KA-POW! You're devoured by a snaggletoothed shark. Unfortunately, this is the harsh reality for napping Arctic harbor seals. Scientists have discovered that Greenland sharks, the seals' predators, are the slowest fish in the sea, topping out at less than 1 mph and making them incapable of catching the sprinting seals that make up their diet (so much for that tough-guy attitude). The horrible conclusion: The marine killing machines sneak up on the fuzzy critters as they doze under water. There's some food for thought as you're floating around on the shore this summer.