HOW DO SOME FISH GENERATE ELECTRICITY?
Nicola Stanislawska
Electric fish are a rare but intriguing phenomenon. In their usual habitat where light is scarce, most use their unique power for navigation and communication. Yet some rare species harness this ability in hunting. But how do electric fish produce an electrical current and how do they use it for their advantage?
Every electric fish possesses electric organs that produce electricity. The fish’s brain sends a signal through its nervous system to the electric organ. The organ is filled with hundreds of thousands of disk-shaped cells called electrocytes. Electrocytes pump out sodium and potassium ions maintaining a positive charge outside and negative charge inside.
When nerve signals arrive at the organ, they cause the ion gates to open. The positives ions flow back in creating a negative charge on the on the outside of the electrocytes creating a current. As the nerves arrive at the same time, the electrotypes act like thousands of batteries in series.
The ways fish harness this ability varies. The nearly 350 types of electrical fish are divided into two sections, strongly electrical and weakly electrical fish.
Weakly electrical:
As the name suggests, weakly electrical fish produce a weak current that is typically up to one volt. The electric organ in their body is located near their tail. This means that they are unable to create a current strong enough to paralyze their prey. Instead, they use this ability to communicate and detect shapes and sizes of nearby objects.
