When life throws out a challenge to survival, animals have to come up with creative ways around it—or risk extinction. Their solutions are often ingenious—and stranger than anything we can imagine. The moray eel had to evolve a second set of teeth in its throat just to swallow. The Komodo dragon can kill with bacteria to make up for its weak jaws. And sand tiger sharks eat each other in the womb, so they can be born big and strong. In a world where only the fittest survive, the future belongs to these mutating problem-solvers.

For animals in the wild, preparing for emergency situations can mean the difference between life and death. From beavers building emergency bunkers to spiders laying hairspring traps to catch their next meal, these creatures prepare for just about anything in some of the world's weirdest ways.

Sharks are one of the oldest species on the planet, so they have had plenty of time to evolve and develop some of the weirdest and most diverse skills and survival tactics. Discover the odd behaviors of sharks of all sizes, from the vicious hunters to the scrappy bottom-feeders, as they have never been seen before.