The Migration of the European Eels

[corynski]

Async,

Sounds like you're in good humor, good to hear from you. I did in fact purchase a book by Dr. Stephen T. Chang, titled 'The Complete System of Self-Healing', Internal Exercises. Unfortunately though, I discovered about the same time that I don't have any free will, and I can't hardly get started with the exercises. I can get myself to take a good walk in the morning but that's about it. "I" just can't get "me" to do what "I" want.......

Regarding everything else, I've decided to become a determinist for the sake of simplicity. One atom hits the next atom and there's no such thing as 'chance'. It's turtles all the way down mate......

Confused in Tennessee

[Quasar]

Thus I cannot be question-begging because my premise is not that evolution occured in this case, but rather that it is possible that evolution occured in this case.

You are the one supporting the theory of evolution, though you seem to be disclaiming responsibility. That's fine by me. But in more general terms, the theory HAS to account for the origin of the behaviour.

Correcting your misinterpretation of my position is not the same as disclaiming responsability. I still believe that evolution can (and has) provided a plausible explanation for the origin of this behavior. But I am not trying to use that explanation as evidence in favor of evolution: that would be absurd.

It is impossible for any fish to swim 3,000 miles at a depth of about 3000' at night, and find its way successfully to the destination. At least, it is impossible for it to do this by using 'small incremental additions' to its movement. It should be obvious that if the instinct was faulty at any stage, then

a. they would not have got there, and

b. would not have returned.

How would either of those outcomes prevent the eels from reproducing if the entire species had a similar "faulty" (a better term would be "primitive," given that an underdeveloped beneficial feature is still better than no feature) instinct?

The theory fails to account for such an impressive phenomenon. I may point out that science is not a guessing game. The object is not to produce the wildest guesses and them claim them to be possibilities. That is a guessing game, but evolutionists are particulary prone to indulging in guesswork. They've got nothing else.

I find your emotionally-charged rhetorical statements to be unconvincing. Plausible hypothetical's have a place in science, when positive evidence is not enough to conclusively prove or disprove an idea. Correlation with other evidence, (in this case, the evidence that all species are decended from a common ancestor) can give a plausible hypothetical a high level of significance.

Anything is possible, I suppose - the eels may even fly there: that's a possibility, but we won't go there, shall we?

Given that the eel's method of transportation has been identified as underwater swimming, I find your hypothesis to be unlikely.

No, to present your unsupported guesses as plausible possible mechanisms, will not do. In science, anyway.

"Unsupported guesses" are an integral part of science. We call them "hypotheses."

Again, I am trying not

I believe that you are engaging in the practice known as "shifting the goalposts." Your original request was for an evolutionary path from a fresh-water to salt-water marine organism, which has remarkably little to do with the cambrian explosion.

No, my original request was for a plausible mechanism by which this migration's origin could be accounted for. You were the one doing the diverting.

My apologies, I did not intend to misrepresent your original request. I still fail to see what this has to do with the cambrian explosion. The behavior under discussion in not proposed to have evolved for many millions of years after that era.

I can't get your link to work, but you are quite wrong if the BBC program I saw was anything to go by. Here's a comment by one researcher:

The eels that had migrated the furthest had swum more than 1000 kilometres from the Irish coast. Kim Aarestrups says:"It is very interesting that eels do not migrate directly towards the Sargasso Sea, but instead takes a more southern route towards the Azores. Researchers had previously speculated that eels should migrate south of the Azores to catch a ride on the south and west going currents and this way speed up their migration. Perhaps they were right!"
http://www.wildlifeextra.com/go/news...els938.html#cr

My link was simply to a global image of the worlds currents. I provided it to clear confusion as to the path the eels take as compared to the worlds currents. It would not be difficult to find a similar image via the google search engine.

The paragraph you quote supports my assertion that the eel's follow the current.

If the eel's follow the current south from Europe, they will follow the canaries current to the west edge of Africa, join up with the faster Northern Equatorial, and head north-west along the coast of South America to the Sargasso Sea. Interestingly, the North Atlantic Current also provides a means for the baby eel's to hitch a ride back home.

Sorry, wrong again.

Your assersion is entirely false. Both of our sources agree in all aspects with the migration path I proposed above. I again encourage you to track the eel's journey on a map of the oceans currents, to prevent further embarrasment on your behalf.

(Wow. I went over the character limit. I didn't know that was possible. Continued in next post)

[Quasar]

No. The earliest examples would have remained fairly close to their breeding grounds. However, in order to expand their population further whilst still maintaining maximum genetic variety (to prevent inbreeding), they would have had to slowly increase the distance travelled.

Two points.

1 They do not learn.

2 Even if they did, they could not transmit the info totheir offspring. That's Lamarckism, which you are unconsciously pushing here. Sorry.

I am again forced to repeat myself: I am not proposing Lamarkism. I have been very clear on the difference between learned and instinctual behavor. I am unclear as to why you continue to misrepresent my arguments.

This is elementary behavioral evolution. I do not understand why you would reference Lamarckism: I am not proposing that their actions affect their genes. I am, however, proposing the inverse.

I'm afraid you are proposing Lamarckism, as Dawkins does, but refuses to admit. ANY LEARNED BEHAVIOUR WHICH IS TRANSMITTED is Lamarckian in nature.

I am not proposing Lamarckism. I will engage the use of capital letters for the following statement, because you appear to have missed it previously and it is common knowledge that capital letters increase the persuasiveness of any argument. THE BEHAVIOR THAT IS TRANMSITTED IS INSTINCTUAL, IT IS NOT LEARNED.

Any purposiveness in behaviour is also contrary to basic, elementary evolutionary principles. That is what you have proposed with your words: " in order to" above.

I apologise. I worded the statement you refer to in a simplistic format that would seem to imply purposefulness, with the intention of getting the information across in as compact a way as possible. I mistakenly believed you to be capable of understanding that I was referring to the actions of natural selection, wherein it acts in such a way that would promote the proliferation of the species, which is analagous to a "purpose" for the contexts of the conversation. I will be more careful with my wording in future, so as to avoid such misunderstandings.

As things now stand, that is a correct statement. However, we are not discussing how things now stand. We are discussing the ORIGIN of the behaviours in question. We are discussing HOW THOSE BEHAVIOURS COULD POSSIBLY HAVE ENTERED THE GENOME - which is probably where they are now.

Mutation and culmative natural selection. Are you claiming that these forces cannot result in the slow increase in intensity of a behavioral attribute?

So your above statement is question begging, again. You have assumed that it HAS entered the genome, by ways and means unspecified. But you are being called upon to account for how the unspecified DID happen.

You are also assuming that it has entered the genome, by ways and means unspecified. This is a somewhat necessary assumption, given that it exists in the genome. I fail to see how making it can be construed as question-begging, given that the premise in question is not that it exists in the genome, but is that it is possible that it formed by the mechanisms of evolution, a claim that you dispute.

One proposal for the significant distance they travel is that it is a vestegial effect from their evolution: once they had developed behaviour that sends them to the ocean as adults, the currents would disperse them.

Again question begging. "From their evolution" assumes the case."Once they had developed behaviour" is even worse.

You appear to be somewhat fond of invoking this fallacy. However, I am not engaging in it. I am not trying to demonstrate that the eel's journey is evidence of evolution: I am merely attempting to disprove your assersion that the evolution of said journey is impossible. Hypothetical evolutionary pathways are thus a valid argument, and not question begging.

It might be construed, if one were feeling cynical, that your repeated invoking of this logical fallacy is due to a wish to divert attention from an inability to demonstrate a valid reason that these hypothetical pathways are implausible.

I'm pretty sure they could have fund a mate by the time they left the European waters, and at any point in the 3000 mile swim.That doesn't hold water, because all the mates come from the band that left European waters.

However, the global currents do not converge on any area as close as the Sargasso Sea. If they are indeed following the currents to find a mate, it is plausible that the Sargasso Sea is simply the nearest large convergence of currents. They would have to swim against the current to find any closer breeding ground.

Eels that followed the currents to the sargasso sea encountered other eels that had been brought there by the currents, gaining a reproductive advantage. Their offspring then need to get to the safety of a river mouth, and given that the currents return them to Europe it makes sense to go straight there. Another possiblity is climatic: perhaps the young eels survive better in a cooler climate. My understanding is that there are fewer predators in cool waters.

I'm sorry, quasar. This is a pathetic excuse for an explanation. A 3000 mile trip, with no information about the journey, direction, length of time, or basically ANYTHING really relevant, is a perfect recpie for disaster and extinction. Sorry, this will not do.

I again find your emotionally-charged rhetorical statements to be unconvincing. You have not given any reason that my hypothetical is a "pathetic excuse," beyond an argument from incredulity.