Why don´t electric eels fry themselves?

[Ale]

I was watching a documentary today where an electric eel showed up shocking and knocking out a fish before gulping it.
Seems that the critter can pump 500V at 1 Amp wich is quite a spark IMHO, that got me wondering how these fish avoid beign shocked by their own discharges.

Any ideas?

[David_Simmons]

I suppose that as the source of the electric field all parts of their body is at approximately the same potential. Or at least the potential difference across their body is relatively low.

[GIGObuster]

http://school.discovery.com/studystarters/facts/fish_thatshocking.html

Yet it can’t shock other eels — the electric eel has a layer of fat that insulates it from shocks.

What is interesting now is that when surfing for the answer, I noticed odd electric eel info:

-They have no problem sending shocks all over when mating, but they are still capable of shocking each other when fighting.

-Reports of eels becoming eventually blind since eyes are not protected by the layers of fat.

Now, one of the sources was the Weekly World News :dubious: but because they were right about the layers of fat, I wonder if other researchers agree with that.

[engineer_comp_geek]

Electric eels are capable of producing a low level shock and a high level shock. The low level shock is significantly lower in voltage, something like 10 to 50 volts, compared to somewhere around 500 volts or more for the bigger shock. The eel’s skin insulates it from the shocks, but not completely. I’ve read that the high level shock actually hurts the eel a bit too. I’ve also read that if their skin is damaged (due to fighting or injury or whatever) that it is possible for them to shock themselves to death.

[Ale]

@GIGObuster

http://school.discovery.com/studystarters/facts/fish_thatshocking.html

What is interesting now is that when surfing for the answer, I noticed odd electric eel info:

-They have no problem sending shocks all over when mating, but they are still capable of shocking each other when fighting.

-Reports of eels becoming eventually blind since eyes are not protected by the layers of fat.

Now, one of the sources was the Weekly World News :dubious: but because they were right about the layers of fat, I wonder if other researchers agree with that.

Fat is an insulator? :dubious:

[Ale]

Darn, I hit submit too soon…

@engineer_comp_geek

Electric eels are capable of producing a low level shock and a high level shock. The low level shock is significantly lower in voltage, something like 10 to 50 volts, compared to somewhere around 500 volts or more for the bigger shock. The eel’s skin insulates it from the shocks, but not completely. I’ve read that the high level shock actually hurts the eel a bit too. I’ve also read that if their skin is damaged (due to fighting or injury or whatever) that it is possible for them to shock themselves to death.

If the skin acts as an insulator that still leaves the problem of how the critter doesn´t get shocked by the electricity generated inside its body.

Maybe electric fish are just built to withstand the shock; intriguing…

[GIGObuster]

@Ale

Fat is an insulator? :dubious:

Well, it seems that was only partially correct.

http://www.theanswerbank.co.uk/Animals_and_Nature/Question2811.html

The fat conducts electricity poorly compared with the surrounding water. Electricity takes the path of least resistance, so it flows through the water and not the eel.

Because the prey is usually smaller than the eel, once again electricity follows the path of least resistance, in this case the less insulated small fish.

http://www.madsci.org/posts/archives/jun2000/960860141.Zo.r.html

The individual cells of the electric organ are
designed such that only one side of the cell carries the electric
potential, and all of the cells are aligned similarly. Thus the charge is
carried in one direction from the body. The head then acts as the
positive end of the ‘battery’, and the tail as the negative. When the eel
is resting there is no electricity generated from the organ, but when it
begins to move it emits electrical impulses. In some electric fishes, this
electric current is used for communication and/or recognizing prey items.
In the electric eel, when the eel touches its tail and head to an animal,
it sends electric shocks through that animals body, much the same way, you
can shock someone with static electricity and not get shocked yourself.

[David_Simmons]

@GIGObuster

once again electricity follows the path of least resistance, in this case the less insulated small fish.

it sends electric shocks through that animals body, much the same way, you can shock someone with static electricity and not get shocked yourself.

Once again, electric current divides inversely as the impedances in parallel and electric voltage divides directly as the impedance in series.

And when I shock someone with static I also feel it but I’m expecting it and they probably aren’t.