Electric Eel [Photo from Bettman Archive & Corbis]
Electric eels gulp air from the surface in order to breathe. Thanks to specialized internal organs, they can produce pulses of electricity greater than 500 volts, with a current greater than one amp. That's enough to kill an adult human being.
Electric eels mostly hunt invertebrates, though adults also consume fish and small mammals. They only attack human beings if they are disturbed. They tend to live in murky, stagnate waters. Scientists have long been fascinated by the species and have probed its impressive electrical abilities.