How does an electric eel produce electricity

00:00 Mon 21st May 2001 |

A. An electric eel's body has thousands of special cells, called electrolytes, which produce electric currents. The individual cells, which are modified muscle cells, are stacked together along the length of the eel, like a battery (to read how batteries work, click here). The head acts as the positive pole of the battery, the tail as the negative pole.

In isolation, each cell can only discharge a tiny amount of electricity, but eels have developed a mechanism that stimulates each electrolyte simultaneously, together they can give a powerful shock.

Because water is an excellent conductor of electricity eels are able to use their electricity emitting bodies to stun and kill prey and navigate.

Q. Does an electric eel generate electricity all the time

A. No, when it's resting no electricity is emitted. When it starts to move around 25 electrical pulses are sent out every second. An electric eel needs to 'recharge' if it's been emitting numerous volts over a short time, for example after an intense feeding session, when up to 50 discharges a second are possible.

Q. Could a shock from an electric eel kill me

A. Probably not. The most powerful discharge is emitted by the electric eel, Electrophorus Electricus, found in certain South American rivers. This electric eel can stun large animals with its shock. Adult electric eels 5ft to 7ft long produce enough electricity, 600 volts, to stun a horse.

Q. Can an electric eel shock itself

A. Thanks to mother for this question, click here to see Sensei's answer.

Given that water is such a good conductor of electricity eels should be at risk of shocking themselves and the reasons for electric eels' immunity to their own electricity are not fully understood.

It's thought that the insulating properties of their skin and tissues stop them short circuiting themselves. Some eels have been found suffering from their own electric shocks if their skin was already damaged.

Both males and females emit bursts of electricity when mating, but aren't not effected by them. However, for unknown reasons, these bursts can kill the other eel if they're emitted when they're not mating.

Q. Are there any other marine animals that are electric

A. Yes, there are electric fish and electric rays, but the South American electric eel, Electrophorus Electricus, emits the most powerful discharge.

Q. How do electric eels use electricity to navigate

A. The eel's pulses of electricity are sent through the water and become distorted if they hit prey or other objects. The eel uses electroreceptors and a sophisticated data processing system to build up an 'image' of their surroundings based on these distortions.

Do you want to know about an animal's special defence mechanism Click here to ask

by Lisa Cardy

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