Humans can't hear infrasound, which scientists define as any sound pitched below 20 hertz to as low as 2 hertz. But it turns out that some animals, including elephants, hippos, giraffes, whales, and alligators, have acute infrasound hearing.

We've all heard them: the tales of dogs barking before the big earthquake hit; wildlife behaving strangely before the big hurricane; earthworms pouring out of the ground just before the big flood strikes. Tall tales ... or true?

In interviews with scientists and eyewitnesses, NATURE probes the evidence that some animals may have senses that allow them to predict impending natural disasters long before we can.