Hi Haldir, welcome to EvC! It's fun here, feel free to look around 'n stuff.
The Source writes:
We do not know the crucial features that evolved to alter the adequate stimulus from a mechanical event to an electrical one, but the change in sensitivity was many orders of magnitude and, in each class of electroreceptor, was tuned to a best frequency that could be many octaves apart.
Can you explain what the source is talking about here?
The sensitivity of what?
Is the source claiming that a regular eel went to an awesomely electrical electric eel in one step?
Or are they claiming that they simply don't know what happened to take a regular eel to an awesomely electrical electric eel over a very long time?
Haldir writes:
1. A change in sensitivity of many orders of magnitude.
If this is claimed to be quick, then I agree a problem exists.
If this is claimed to be slow... I don't see a problem. Things specialize all the time. Why wouldn't an advantage specialize itself over time?
2. A change in the organization of the muscles so that the voltage increases by lining them up
Again, this seems to be a specialization thing
after electrocution begins.
What if the electrocution was very small at first, and only used for something like communication even?
Then maybe it later evolved to get stronger and stronger and eventually became a potent weapon. If so, optimizing muscle organization would be a simple degree of slow movements towards advantage.
3. Tuning the electroreceptors to a "best frequency"
Again, seems to be something that could happen quite easily over time.
4. The ability of all the muscles to fire at the same time
Again, not difficult to envision as evolution over time adds up.
5. (Possibly) The loss of the muscles' ability to contract (Articles mention this as happening, and the electric function replacing them, but I'm not sure yet if this function would have to be lost for the electric function to work, or if it could have just happened later to no disadvantage)
Everything you've listed so far seems like it could "happen later to no disadvantage."
6. (Possibly) An increase in fat around the head / vital organs to protect it from shocking itself (This seems to depend on whether or not this is what actually keeps it from shocking itself. Alternately, #6 could be whatever the actual method is of preventing shock, unless it is really something that was present all along.)
If the strength of the shock increased slowly over time, it wouldn't be difficult for the "actual method of preventing (self-)shock" slowly evolved with it.
Is anyone claiming that a non-electric eel turned into an awesomely powerful electric eel very quickly?
That's the only way I can see your questions making a lot of sense. But... I don't see this claim anywhere. Maybe you do know about it and can point it out?
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