1 / 5
by: Cristen Conger
A Sense of Powe

Most sharks wouldn't perform well on an eye exam. If you take a close-up look at a shark's face, you'll notice that its eyes are quite small in proportion to the size of its head. Also, a shark's headlights are usually situated farther back toward its neck, limiting its scope of vision.

Fortunately for sharks (and unfortunately for their prey), they have a sixth sense called electroreception, which enables them to hunt precisely underwater. Special pores around their faces act as homing devices and detect the electrical currents that other organisms emit. The salty aquatic environment transports those electrical currents toward the shark. These five cool components of electroreception demonstrate just how incredible this shark sense is.

Electroreception operates on the same general principles at work inside a battery. Whenever a living organism, such as a fish, contracts a muscle, it creates a faint electrical charge. That charge travels through the salty ocean water, thanks to the sodium and chlorine ions floating throughout it. Those ions possess positive and negative charges, and the fish's cells are also slightly charged. Therefore, when the living cells on the fish come into contact with the free-floating sodium and chlorine ions, the ions exchange electrons in order to become more stabilized. That electron exchange then creates a weak voltage that sharks can sense.

About the blog:
More on
Shark Week