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  #1  
Old 07-27-2001, 05:31 PM
marekd marekd is offline
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I was watching a programme on the TV the other day about what happens to the rainforests when the Amazon basin floods. They showed lots of creatures, about how they adapt to the flooding and so on.

One of the creatures was the electric eel and they showed how it stunned its prey, which was cool. Apparently it gives off 600 volts of electricity when it does this. My question is how does it not, at least, shock itself or anything else in its vaccinity, except whatever it touches?

This defies logic as everyone knows that water and electricity don't mix.
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  #2  
Old 07-27-2001, 06:36 PM
Morbo Morbo is offline
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IANAEE

Sorry I have no cite, and I looked, but IIRC electric eels have a thick layer of fat that acts as an insulator. This natural insulation protects them from their own (or other) bursts.
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Old 07-27-2001, 08:03 PM
MrDeath MrDeath is offline
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Really long grounding straps?
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  #4  
Old 07-27-2001, 08:21 PM
sailor sailor is offline
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A very shocking question indeed but I am sorry I am not current on this as I lack the capacity to understand how this might work. Did the eel meet with resistance from the prey? Was the eel charged with assault?
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  #5  
Old 07-27-2001, 10:45 PM
Fredge Fredge is offline
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Quote:
Originally posted by Dooku
IANAEE

Sorry I have no cite, and I looked, but IIRC electric eels have a thick layer of fat that acts as an insulator. This natural insulation protects them from their own (or other) bursts.
Will my thick layer of fat do the same for me? Maybe there is a good reason to keep it after all?
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  #6  
Old 07-28-2001, 01:18 AM
Dijon Warlock Dijon Warlock is offline
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Before the days of Thomas Edison, electric eels had to stun their prey with gas.

Or so I've heard.
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  #7  
Old 07-28-2001, 02:05 AM
choosybeggar choosybeggar is offline
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Quote:
Originally posted by sailor
A very shocking question indeed but I am sorry I am not current on this as I lack the capacity to understand how this might work. Did the eel meet with resistance from the prey? Was the eel charged with assault?
Electrifying! A lightning stroke of genius.

marekd, the reason why the eel isn't hurt is that the current doesn't travel through it's body. The current producing organs are on the surface of the eel, and when they discharge, the current travels towards ground. When you're in a river, ground is all around you. So current flows from the eel outwards, creating tempura in its wake.
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  #8  
Old 07-28-2001, 02:48 PM
sailor sailor is offline
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Watt can I say? I find eels re-volting but living in the bottom of the sea they must feel insulated from the outside world. Maybe we could induce them to move although I would not want to be the one to conduct such a scheme. LED them remain.
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  #9  
Old 07-28-2001, 05:25 PM
Cardinal Cardinal is offline
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All the bad puns here are disturbing my aura. I need to go meditate.


Ohmmmmm... Ohmmmmm...
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  #10  
Old 07-28-2001, 06:02 PM
sailor sailor is offline
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Give a man an eel and you've shocked him Faraday...
but if you marry him to the eel he'll be in shock for quite a while.

While I feel a magnetic attraction to making puns I gauss this is getting tiring...
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  #11  
Old 07-28-2001, 07:27 PM
Markxxx Markxxx is offline
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  #12  
Old 07-28-2001, 10:01 PM
Qwertyasdfg Qwertyasdfg is offline
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My Theory

Contrary to popular opinion, water is not a conductor. Its the salts that acutally conduct electricity.

Thus, if eels are freshwater (as I beleive they are) it is possible (keep in mind this is just my guess) that they might not conduct the current into the water and only effect what's touching them.

How they don't harm themselves? I have no idea.
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  #13  
Old 07-28-2001, 11:58 PM
mmmiiikkkeee mmmiiikkkeee is offline
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Right theory on water not conducting a current, but not quite accurate in practice. Absolutly pure water won't conduct a current. However, the tropical rivers or swamps the eels live in are far from pure. So is just about any natural fresh water... you can still get fried in a bath tub, even if the only salts present just washed into the water from your skin. I'd say any water source containing life will conduct a current to varying degrees. Muddy water will have even more conductivity. Markxxx's post has the best description of how the eels protect themselves... even though it's not fully understood yet. My question is even if they have insulated outer skin and nerves on the body, how do they prevent the current from entering through their gills which are notoriously thin-skinned and fragile in all fish? Just keep their mouths closed I guess.
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  #14  
Old 07-30-2001, 07:22 AM
Marcus Marcus is offline
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When an eel lunges out
And bites you on the snout
It's a moray
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  #15  
Old 07-30-2001, 08:53 AM
sailor sailor is offline
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a punishing thread indeed *_*
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  #16  
Old 07-30-2001, 09:32 PM
rowrrbazzle rowrrbazzle is offline
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Quote:
Originally posted by sailor
Was the eel charged with assault?
And battery.
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  #17  
Old 07-31-2001, 10:40 AM
sailor sailor is offline
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New and improved(?)

I can understand how you would feel electrified by this question, a very shocking question indeed which resonates in my mind and which I cannot brush aside. I even know of a lady who suffered an attack of hysteresis as a direct result when she was told this. It has me galvanised and I do not understand how some people can feel neutral or even reluctant about it, but I am sorry I am not current on this as I lack the capacity to understand how this might work. Still, I often go through cycles when feel a magnetic attraction to the subject alternating with despair that I will never know the answer. It just brings up a series of questions: What is the primary reason for this behavior? Is the eel a dynamic animal or does it lack energy? Did it meet with resistance from the prey? Was the eel charged with assault and battery? Watt was the prey's reactance? Did it have the power to defend itself? With what frequency does the eel do it? Personally I find eels re-volting but living in the bottom of the sea they must feel insulated from the outside world. Suddenly a light turned on in my brain: Maybe we could induce them to move closer to the poles if only far-a-day and they may feel transformed during this phase. Other tests could be done in parallel although they could be shunted by lack of funds. On the other hand, I would not want to be the one to conduct such an experiment as I gauss it may be dangerous. Better LED them remain where they are.
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  #18  
Old 07-31-2001, 01:38 PM
Olentzero Olentzero is offline
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Damn you people, this is a GQ thread! Go back to your shanties!

Besides, I'm just mad I didn't think of any of them first.

WAG follows.

I don't know how much 600 volts is but I would guess it's not a whole lot. When I was a young lad in high school physics we got to play with a Wimshurst generator and the teacher made us calculate how much voltage was in the spark being generated. IIRC my calculations came out to something like 2x106 volts which made me think I'd really screwed it up, but he assured me I had figured it out correctly. Of course, he also believed Rutherford and Farady lived in the 14th and 15th centuries, so y'all are welcome to correct me on this.

Anyhoo, given the fact that there was a serious amount of voltage needed just to bridge the inch or so gap between the two nodes, 600 volts probably won't do much of anything outside of what it touches directly. I'll back this up further by saying I once brushed against a 300v wire on an electric fence - not the most pleasant of sensations to be sure, and it kinda knocked me loopy for a bit. Given that it didn't actually arc through the air but jolted me only in direct contact with it, I'd say that doubling the amount of voltage still wouldn't be enough to jolt anything the source wasn't in direct contact with. Even in a better conductor like water.
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  #19  
Old 08-01-2001, 04:47 PM
marekd marekd is offline
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The narrator of the programme said it was enough to kill a small child and stun a grown man. I suppose its relative, but just by looking at the things and what they did i can believe it.
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  #20  
Old 08-01-2001, 06:29 PM
cichlidiot cichlidiot is offline
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I found this interview in text format:

http://www.aip.org/radio/scripts/electric_eels.txt

As an interesting side note, we (my town) at one time had a pet store that kept a pair of electric eels in an aquarium. The owner had set up the tank so the eels actually powered their filtration system and lights. Pretty fascinating stuff.
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  #21  
Old 08-01-2001, 06:59 PM
wevets wevets is offline
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If I'm not mistaken, electric eels and rays mostly stun their prey with shocks of extremely short duration (maybe less than a second... I'll have to look it up). I'm not sure they're capable of even keeping a light bulb lighted (is it possible the pet store owner only claimed they were powering the system? Although I guess if there were many eels in the tank, it's possible).

I'm not sure if this has anything to do with protecting themselves from shocks, but electric rays will bury themselves in the bottom, with only the electric organs and possibly the eyes showing, until something happens along to get shocked.

I think this thread's been dried out of material for puns, but the groans will last for a long time...
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  #22  
Old 08-02-2001, 08:16 PM
wevets wevets is offline
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Update on Eelage

OK, here's some data on Electrophorus electricus, the electric eel. There are also electric rays and catfishes this information may not apply to.

Maximum recorded voltage: 550 volts (at 1 amp). This was recorded for a 2 m long fish (the size of the fish is related to the size of the electrical discharge).

Length of pulses: a few milliseconds, so it's not long enough to heat up the filament on a lightbulb.

These discharges are usually not used to kill, but to either stun prey or convince threating organisms to go elsewhere.

While powerful enough to knock a person down, it's unlikely electric eels could kill a person.

From: Paxton, J. R. and Eschmeyer, W. N. (Eds.). 1994. The Encyclopedia of Fishes, p. 112

Sorry, it doesn't say how they keep from electrocuting themselves, but I think Markxxx's webpage had a good hint on the issue.
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  #23  
Old 08-06-2001, 12:33 AM
sailor sailor is offline
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Should one take special precautions when cooking electric eel over an electric range?

Say, do the 'lectric eels do the electric slide?

::singing:: Ohm, Ohm on the range....::
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  #24  
Old 08-06-2001, 09:47 PM
GulDan GulDan is offline
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My understanding of electric eels (which is a bit rusty) says that they have numerous parallel rows of eletricity generating cells down the lengths of their bodies. As they rows are parallel, the voltage through them is shared so if there are 100 rows (not an unreasonable amount) each cell will receive no more than 6V, a survivable amount.
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  #25  
Old 08-08-2001, 09:45 PM
Sparteye Sparteye is offline
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Quote:
Originally posted by Dijon Warlock
Before the days of Thomas Edison, electric eels had to stun their prey with gas.
Huh. My husband does that to this day.
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