Evolution: Two Intriguing Lamarckian Experiments

[jorolat]

Experiment 1:

About 60 years ago Harry Schroeder performed an experiment on willow-moth caterpillars. At pupation these caterpillars crawl onto leaves, pull the tips over, then wrap the rest of the leaves around themselves.

Schroeder waited until the caterpillars were on the leaves before cutting the tips of the leaves off. The caterpillars responded by using the sides instead. Pupation continued normally thereafter.

When the time to pupate arrived for the subsequent generation 4 of the 19 offspring used the sides of the leaves in preference to the tips.

Experiment 2:

Some time ago Frederick Griffiths performed an experiment on rats whereby they were placed on slowly revolving turntables for periods of up to 18 months or so.

When the rats were removed from the turntables their heads continued to flick in the direction of rotation and so did their eyes. This automatic flickering then appeared in their offspring.


Comment: Imagine the experiment on the caterpillars being repeated along with a control group whose leaves were not altered: If it were found that genetic changes only occurred in the group with tipless leaves then this would begin to indicate that the change in behaviour wasn`t due to chance mutations.

Repeat the experiment often enough, and if the results were consistent, it would soon be statistically impossible for random mutations to be a factor.

The second experiment, though appalling, also had a potential: If it had been continued then grotesque structural changes similar to those found in flatfish might have occured.

The results of both experiments are of personal interest because they would be consistent with the existence of an internal evolutionary mechanism based on an extension to homeostasis.

References to these experiments are to be found in "The Great Evolution Mystery" by Gordon Rattray Taylor (Secker & Warburg, London). If any Reader knows the location of the primary sources of these, or similar, experiments it would be greatly appreciated.

Jorolat

[Short]

What springs to mind is the work of Tracy M Sonneborn.

[Sonneborn] also exposed stenostomumto lead acetate and found that abnormalities appeared. After such treatments he was able to isolate two-headed "monsters" that reproduce true to type. Since these traits were maintained for many generations, they were judged to have a hereditary basis. However, these variants arose and were lost at a much higher frequency that one would expect if they were due to mutations in simple Mendelian genes
From National Academy Press Biographical Memoirs, pp276 (http://books.nap.edu/books/0309053463/html/276.html#pagetop)

My knowledge of biology is limited, but more information can be found in the chapter (http://books.nap.edu/books/0309053463/html/268.html) from which I quoted.

Interestingly enough, Annals of Improbable Research (a rather funny "joke" journal) noted this as well, but prefaced that the column was "not necessarily humorous." That can be found here (http://www.improb.com/airchives/paperair/volume6/v6i2/sonneborn-6-2.html).

[Phobos]

Experiment #3. Will continual posts to the wrong forum change Manhatten's behavior? :)

[RealityChuck]

Experiment #3 (ongoing):

1. Take an ethnic group (say Jewish).
2. Circumcise them just after birth.
3. Repeat for 5000 years.

And that's why Jews no longer have to be circumcized.

No, wait . . .

[choosybeggar]

Originally posted by jorolat
Comment: Imagine the experiment on the caterpillars being repeated along with a control group whose leaves were not altered: If it were found that genetic changes only occurred in the group with tipless leaves then this would begin to indicate that the change in behaviour wasn`t due to chance mutations.

Repeat the experiment often enough, and if the results were consistent, it would soon be statistically impossible for random mutations to be a factor.

The second experiment, though appalling, also had a potential: If it had been continued then grotesque structural changes similar to those found in flatfish might have occured.

[angry southwestern furniture store owner]Yeah, and if a frog had wings he wouldn't bump his ass a hoppin'![/angry southwestern furniture store owner]

Lots of badly controlled experiments produce intriguing results. There are many if's and woulds in your commentary. Interesting as the studies you cite are, I don't see how they support a case for Lamarkianism. Have either been replicated?

[jorolat]

Hi Short,

Thank you for your reply. I am currently researching the possibility of an internal evolutionary mechanism. The two experiments referred to in the original post appear to meet the mechanism's associated "method of testing" and hence my interest in their original sources.

Both of your links provide are interesting, however, and Sonneborn's work on stenostomun and the paracecium may be relevant to how the proposed mechanism works in simpler critters.

Jorolat

[jorolat]

Originally posted by Phobos
Experiment #3. Will continual posts to the wrong forum change Manhatten's behavior? :)

I am new to "straightdope", would the original post have been better suited to another forum?.

Jorolat

[douglips]

Suggested change to experiment #2:
Have the baby rats raised by other rats who have not been screwed up.

I imagine that when growing up if my mom and dad were constantly shaking their heads and eyes that I'd begin to do it to.

[jorolat]

Originally posted by RealityChuck
Experiment #3 (ongoing):

1. Take an ethnic group (say Jewish).
2. Circumcise them just after birth.
3. Repeat for 5000 years.

And that's why Jews no longer have to be circumcized.

No, wait . . .

Inflicting physical trauma on successive generations of any organism proves nothing beyond how potentially dangerous a detached intellect can be to natural life.

I do not mean this in a personal way, just stating a fact.

To test a homeostatic mechanism it is necessary to fine tune the degree of "stress" an organism is subjected to because physical trauma, generally speaking, would tend to be outside the "recapture range".

Jorolat

[jorolat]

Originally posted by angry southwestern furniture store owner
Yeah, and if a frog had wings he wouldn't bump his ass a hoppin'!

Lots of badly controlled experiments produce intriguing results. There are many if's and woulds in your commentary. Interesting as the studies you cite are, I don't see how they support a case for Lamarkianism. Have either been replicated?

It is the potential of the experiments to illustrate a method of testing for a proposed internal evolutionary mechanism that I am in interested in.

Unfortunately I have only been able to find secondary sources so far and have little information beyond that given in the original post.

Jorolat

[jorolat]

Originally posted by douglips
Suggested change to experiment #2:
Have the baby rats raised by other rats who have not been screwed up.

I imagine that when growing up if my mom and dad were constantly shaking their heads and eyes that I'd begin to do it to.

The second generation rats could have been born with:

a) No change in behaviour
b) Heads flickering only
c) Eyes flickering only

They were, in fact, born with both head and eyes flickering. The emphasis is on the "born".

Jorolat

[PosterChild]

Originally posted by jorolat
Repeat the experiment often enough, and if the results were consistent, it would soon be statistically impossible for random mutations to be a factor.

...If it had been continued then grotesque structural changes similar to those found in flatfish might have occured.


I think the fact that these experiments haven't been repeated in a controlled fashion is almost a statement in itself. In fact, I think these experiments have been performed, but didn't show the changes hoped for. (Think Duesberg & AIDS, or Lamark himself, or cold fusion, or Choosybeggar's PhD work.:))

PosterChild

[bryanmcc]

The fact that you haven't been able to find primary sources in peer-reviewed journals should perhaps indicate to you that these studies were not legitimate, respected, accepted, and/or repeatable.

Granted, your summaries of said experiments were brief, but I can find several obvious flaws with the conclusions drawn from them, to wit:

Four out of 19 in an experiment run only once is hardly conclusive, and is barely even enough to justify speculation. This is especially a problem when it is not stated what numbers, if any, of the parent population displayed this behavior. My guess would be that some number of this species ALWAYS display this behavior.

While in your last post you do add that they were "born" this way, your initial post merely described that the offspring exibited this behavior. douglips was fully justified in that the offspring aquired this behavior through observation and mimicry.

These claims are further hard to accept when -- although you have mentioned an unspecified mechanism several times -- we are not presented with any conceivable mechanism by which these processes could be achieved. Darwinian selection has a simple and observable mechanism by which it is carried out, but I do not see how that could be the case with your examples.

Also, RealityChucks example -- along with the classic example of successive generations of rats subjected to removal of the tail -- seems to be clear evidence against Lamarckianism. If for 5000 years the foreskin of all males has been removed at birth, why ARE they still born with foreskin? Your refutation smacks of arbitrary dismissal. "Just stating a fact" how? Why is physical trauma inflicted in a consistant manner not stimulus enough to cause the Lamarckian effects you are claiming? Please make a logical argument for this rather than just dismissing a reasonable criticism with personal attacks.

-b

[jorolat]

Originally posted by PosterChild
Originally posted by jorolat
Repeat the experiment often enough, and if the results were consistent, it would soon be statistically impossible for random mutations to be a factor.

...If it had been continued then grotesque structural changes similar to those found in flatfish might have occured.


I think the fact that these experiments haven't been repeated in a controlled fashion is almost a statement in itself. In fact, I think these experiments have been performed, but didn't show the changes hoped for. (Think Duesberg & AIDS, or Lamark himself, or cold fusion, or Choosybeggar's PhD work.:))

PosterChild

These experiments were performed some time ago and I feel the reason they surface from time to time (on newsgroups etc.) is because some people intuitively recognize they have a potential significance but do not know what it is.

From my perspective they appear to relevant to the evolutionary mechanism I am interested in but finding the primary sources may prove that this is not so.

If I had the resources I would be tempted to repeat the experiment with the caterpillars but on the other hand I could constuct experiments for any number of different organisms.

My area of interest is still developing and at this point in time it would simply be nice to be able to say "these experiments inadvertently met the criteria for the proposed method of testing" with more certainty.

I feel many people believe in the theory of evolution in the same way that they once believed the earth revolved around the sun: It is what they have been conditioned with and to such an extent that the capability for original thought is impaired.

This results in any new proposal being met with a negative knee-jerk reaction as dogma (which they can never know for themselves anyway) is regurgitated.

I believe that evolution has occured (and is occuring) but that it is natural rather than theoretical.
This means it must be entirely testable.

Jorolat

[egkelly]

Interesting thread. Does anybody know if the experiments of Paul Kammerer (Austrian biologist) have evr been repeated? Supposedly, Kammerer was able to see changes in newts, which tended to support lamarkism.
I don't know any more about this-Kammerer commited suicide, due to the discovery that some of his research had been faked!

[bryanmcc]

Sure, the possibilities are intriguing, but one has to wonder why, if the experiments have merit, they haven't been repeated extensively. I mean it's not like were talking huge, multi-million dollar investments here: get some caterpillars, a few leaves, and some graph paper and you're set! Or a few lab rats and a lazy susan.

Try going onto Science or Nature's web site and entering "Lamarckianism" into the search engine.

And so many people believe in evolution because there is an entire mountain of observational evidence, lucid arguments, confirming experiments, and a reasonable mechanism behind it.

And which part of evolution, exactly, isn't "entirely testable?"

-b

[Gaspode]

Originally posted by jorolat
Originally posted by douglips
Suggested change to experiment #2:
Have the baby rats raised by other rats who have not been screwed up.
I imagine that when growing up if my mom and dad were constantly shaking their heads and eyes that I'd begin to do it to.
The second generation rats could have been born with:
a) No change in behaviour
b) Heads flickering only
c) Eyes flickering only
They were, in fact, born with both head and eyes flickering. The emphasis is on the "born".

Rats are born in a very underdevolped state. Their eyes are neither open nor functional and they are inacapable of rapid movements of any part of the body. Whenever these animals began displaying these traits and for whatever reason they were definitely not born with them.

http://corbis.altavista.com/referrals/av_image_details.asp?linkid=2623&imageid=10929836

[jorolat]

Originally posted by bryanmcc
The fact that you haven't been able to find primary sources in peer-reviewed journals should perhaps indicate to you that these studies were not legitimate, respected, accepted, and/or repeatable.

I am interested in what is real and would like to quote from an earlier reply:

"I feel many people believe in the theory of evolution in the same way that they once believed the earth revolved around the sun: It is what they have been conditioned with and to such an extent that the capability for original thought is impaired.

This results in any new proposal being met with a negative knee-jerk reaction as dogma (which they can never know for themselves anyway) is regurgitated."

"Four out of 19 in an experiment run only once is hardly conclusive, and is barely even enough to justify speculation."

Twenty percent is, I feel, enough to speculate upon particularly as reflected within the figure is the fact that life is individual. I do not know how many times the experiment was run.

"This is especially a problem when it is not stated what numbers, if any, of the parent population displayed this behavior."

This is one reason why I am looking for the primary sources.

"While in your last post you do add that they were "born" this way, your initial post merely described that the offspring exibited this behavior. douglips was fully justified in that the offspring aquired this behavior through observation and mimicry."

Of course he was and I corrected my omission.

"These claims are further hard to accept when -- although you have mentioned an unspecified mechanism several times -- we are not presented with any conceivable mechanism by which these processes could be achieved."

The appended url (Model of an Internal Evolutionary Mechanism) describes such a mechanism.

"Darwinian selection has a simple and observable mechanism by which it is carried out, but I do not see how that could be the case with your examples."

This is a quote from "Is Evolution A God?" (New York Times Abuzz Forum http://www.abuzz.com/interaction/s.156078/discussion/):

When reading books or articles on evolution phrases such as "Evolution does this" and "Natural Selection does that" often occur usually giving no cause for comment.

Sometimes, however, the distinct impression is gained that the author is using the words "Evolution" and "Natural Selection" in the sense of their being Entities that act on natural life without being part of it.

The apparent conclusion is that these individuals are unconsciously using the terms as psychological alternatives to God - is this why arguments rage between(some) "Evolutionists" and (some) "Creationists"?.

"Natural Selection" does not exist outside of the human intellect.

"Also, RealityChucks example -- along with the classic example of successive generations of rats subjected to removal of the tail -- seems to be clear evidence against Lamarckianism. If for 5000 years the foreskin of all males has been removed at birth, why ARE they still born with foreskin?."

A homeostatic mechanism "works" by integrating transient disruptions to the existing equilibrium over time. Once existing thresholds are exceeded evolutionary changes are then triggered in a direction that restores equilibrium. This brief description presumes that the disruptions are within the recapture range of the organism.

The barbarity of mutilation is largely "nonsensical" from this perspective - too "hit or miss".

"just dismissing a reasonable criticism with personal attacks."

Um, I'm aware of saying things that people may not like but not of making personal attacks.

Jorolat

[PosterChild]

Originally posted by jorolat
Originally posted by PosterChild
Originally posted by jorolat
Repeat the experiment often enough, and if the results were consistent, it would soon be statistically impossible for random mutations to be a factor.

...If it had been continued then grotesque structural changes similar to those found in flatfish might have occured.


I think the fact that these experiments haven't been repeated in a controlled fashion is almost a statement in itself. In fact, I think these experiments have been performed, but didn't show the changes hoped for. (Think Duesberg & AIDS, or Lamark himself, or cold fusion, or Choosybeggar's PhD work.:))

PosterChild

These experiments were performed some time ago and I feel the reason they surface from time to time (on newsgroups etc.) is because some people intuitively recognize they have a potential significance but do not know what it is.

From my perspective they appear to relevant to the evolutionary mechanism I am interested in but finding the primary sources may prove that this is not so.

If I had the resources I would be tempted to repeat the experiment with the caterpillars but on the other hand I could constuct experiments for any number of different organisms.

My area of interest is still developing and at this point in time it would simply be nice to be able to say "these experiments inadvertently met the criteria for the proposed method of testing" with more certainty.

I feel many people believe in the theory of evolution in the same way that they once believed the earth revolved around the sun: It is what they have been conditioned with and to such an extent that the capability for original thought is impaired.

This results in any new proposal being met with a negative knee-jerk reaction as dogma (which they can never know for themselves anyway) is regurgitated.

I believe that evolution has occured (and is occuring) but that it is natural rather than theoretical.
This means it must be entirely testable.

Jorolat

I still believe the earth revolves around the sun.

[jorolat]

Originally posted by egkelly
Interesting thread. Does anybody know if the experiments of Paul Kammerer (Austrian biologist) have evr been repeated? Supposedly, Kammerer was able to see changes in newts, which tended to support lamarkism.
I don't know any more about this-Kammerer commited suicide, due to the discovery that some of his research had been faked!

I do have a recollection of reading about Kammerer but whatever book it was in is not, unfortunately, immediately to hand. Thanks for reminding me of him though!.

A general impression I have of scientists such as Schroeder, Griffiths, Kammerer, and Cairns ("Directed Mutation") etc., is that they intuitively constuct experiments that go beyond the expectations of theory.

Results are then obtained that within the current cultism can only be described as "Lamarckian".

A personal perception of "Lamarckism" is it reflects the reality that life is individual while "Darwinism" (with it's "Populations evolve, not individuals") does not.

The next step from recognizing that life is individual is to look for an internal evolutionary mechanism that is testable.

If an internal evolutionary mechanism didn't exist then the mechanism would have to be external making it supernatural and probably a God. Personally I think this is highly unlikely.

Jorolat

[jorolat]

...I feel many people believe in the theory of evolution in the same way that they once believed the earth revolved around the sun: It is what they have been conditioned with and to such an extent that the capability for original thought is impaired....

Jorolat


I still believe the earth revolves around the sun.

er, so do I...

(grin)

Jorolat

[bryanmcc]

I do not believe that new proposals are met with "a negative knee-jerk reaction," but it doesn't seem unreasonable to require evidence, repeatable experiments, and a straightforward mechanism. I got bogged down on the web-site you referred me to, but it didn't seem to have any of what I just described. Actually, the mechanism being discussed seemed full of assumptions, supositions, and nonsense. If you can explain it more clearly and concisely than it was on that page, perhaps my appologies are in order.

Yes, 20% is a significant result, if it is 2000 out of 10000. Four out of 19 is too close to chance to inspire me (or most, i'd guess) to any undue acceptance. Especially considering the lack of explanation and further results.

I don't think that a New York Times discussion is sufficient to justify the claim that "'Natural Selection' does not exist outside of the human intellect." Natural selection so obviously exists that I don't see how it can be debated. Take 100 ducks, let 'em loose: which ones had survived, which ones reproduced, why did some of 'em fare better than others? Natural selection right there.

Lastly, just because a mechanism lies external to the individual does not make it "supernatural." How can you make this logical leap? Population level, species level, biosphere level, how are these not all part of nature?

[Smeghead]

So, let's summarize. We have an OP that refers to circumcision as "physical trauma" inflicted by "detached intellects", employs nonsensical pseudoscience and calls in evidence, and ignores intelligent refutations of his position.

Oh, dear Cecil!!!

**Runs away screaming**

[Gaspode]

Originally posted by jorolat
[QUOTE]Originally posted by bryanmcc
[b]"While in your last post you do add that they were "born" this way, your initial post merely described that the offspring exibited this behavior. douglips was fully justified in that the offspring aquired this behavior through observation and mimicry."
Of course he was and I corrected my omission.


But you still haven't explained how this behaviour could possibly have been observed in an animal with sealed eyelids, and neck muscles with insufficient strength to support the head. How exactly was it determined that the animals were 'born' with these behaviours?

[manhattan]

jorolat, I'm afraid you've kind of lost me. What, precisely, is (are) the question(s) you are asking here?

[jorolat]

Originally posted by bryanmcc
Sure, the possibilities are intriguing, but one has to wonder why, if the experiments have merit, they haven't been repeated extensively. I mean it's not like were talking huge, multi-million dollar investments here: get some caterpillars, a few leaves, and some graph paper and you're set! Or a few lab rats and a lazy susan.

Try going onto Science or Nature's web site and entering "Lamarckianism" into the search engine.

And so many people believe in evolution because there is an entire mountain of observational evidence, lucid arguments, confirming experiments, and a reasonable mechanism behind it.

And which part of evolution, exactly, isn't "entirely testable?"

-b

I feel the experiments haven't been repeated because no one has been looking for a specific mechanism that could produce such results.

Even more unfortunately I do not have the resources to perform my own experiments (being testable is, after all, at least one merit that the proposed mechanism has!).

I didn't say that evolution isn't testable, in fact I'm saying the opposite.

Jorolat

[jorolat]

Originally posted by manhattan
jorolat, I'm afraid you've kind of lost me. What, precisely, is (are) the question(s) you are asking here?


Simply if anyone knows where I can find primary sources for the two experiments (or references to similar ones) outlined in the original post.

Jorolat

[jorolat]

Originally posted by Gaspode
Originally posted by jorolat
Originally posted by douglips
Suggested change to experiment #2:
Have the baby rats raised by other rats who have not been screwed up.
I imagine that when growing up if my mom and dad were constantly shaking their heads and eyes that I'd begin to do it to.
The second generation rats could have been born with:
a) No change in behaviour
b) Heads flickering only
c) Eyes flickering only
They were, in fact, born with both head and eyes flickering. The emphasis is on the "born".

Rats are born in a very underdevolped state. Their eyes are neither open nor functional and they are inacapable of rapid movements of any part of the body. Whenever these animals began displaying these traits and for whatever reason they were definitely not born with them.

http://corbis.altavista.com/referrals/av_image_details.asp?linkid=2623&imageid=10929836

The secondary source didn't give a moment by moment description of the development of the baby rats but implied that as soon as they were physically capable of beginning to perform the behaviours described then they did so.

Hopefully the primary sourcers will reveal more.

Jorolat

[jorolat]

Originally posted by Gaspode
Originally posted by jorolat
[QUOTE]Originally posted by bryanmcc
[b]"While in your last post you do add that they were "born" this way, your initial post merely described that the offspring exibited this behavior. douglips was fully justified in that the offspring aquired this behavior through observation and mimicry."
Of course he was and I corrected my omission.


But you still haven't explained how this behaviour could possibly have been observed in an animal with sealed eyelids, and neck muscles with insufficient strength to support the head. How exactly was it determined that the animals were 'born' with these behaviours?

I don't have to explain it other than making the comments I made in reply to your earlier post, it wasn't me who performed the experiments.


I'm simply looking for the primary sources to see if they are indeed relevant to my own area of interest.

Jorolat

[jorolat]

Originally posted by bryanmcc
I do not believe that new proposals are met with "a negative knee-jerk reaction," but it doesn't seem unreasonable to require evidence, repeatable experiments, and a straightforward mechanism. I got bogged down on the web-site you referred me to, but it didn't seem to have any of what I just described. Actually, the mechanism being discussed seemed full of assumptions, supositions, and nonsense. If you can explain it more clearly and concisely than it was on that page, perhaps my appologies are in order.

The proposed testable mechanism is radical and arguments for its possible existence are still being developed.

From small acorns do large acorns grow. The contents of the website have been sufficient to earn an invitation to join the evolutionary-psychology egroup (http://groups.yahoo.com/group/evolutionary-psychology), a reference in a foreign press (http://www.hkz.hr/244/24415.htm, acceptance for inclusion in various science directories, a steady trickle of people joining a mailing list, etc., etc..


Yes, 20% is a significant result, if it is 2000 out of 10000. Four out of 19 is too close to chance to inspire me (or most, i'd guess) to any undue acceptance. Especially considering the lack of explanation and further results.

I am looking for the primary sources of the experiments, I didn't perform them. On the other hand my belief that life is individual means that 4 out of 19 can be as significant as 400 out of 2000.

I don't think that a New York Times discussion is sufficient to justify the claim that "'Natural Selection' does not exist outside of the human intellect." Natural selection so obviously exists that I don't see how it can be debated. Take 100 ducks, let 'em loose: which ones had survived, which ones reproduced, why did some of 'em fare better than others? Natural selection right there.

Individual ducks would survive, individual ducks would reproduce, individual ducks would fare better than others. Perhaps an analogy will convey what I mean:

Imagine driving past a golf course just after it has begun to rain and seeing a number of people holding umbrellas. If you return an hour later and it is still raining then you might see more umbrellas in evidence.

The question to be asked is "has the population of
umbrella-carriers grown or have a number of people found a
similar solution to a similar problem?".

What applies to people also applies to ducks, the statement "populations evolve, not individuals" shouldn't be taken literally.

Lastly, just because a mechanism lies external to the individual does not make it "supernatural." How can you make this logical leap? Population level, species level, biosphere level, how are these not all part of nature?

If a mechanism is not part of natural life then surely by definition it must be supernatural?. Populations are made up of individuals etc. etc..

Jorolat

[jorolat]

Originally posted by Smeghead
So, let's summarize. We have an OP that refers to circumcision as "physical trauma" inflicted by "detached intellects", employs nonsensical pseudoscience and calls in evidence, and ignores intelligent refutations of his position.

Oh, dear Cecil!!!

**Runs away screaming**

An extract from a reply to bryanmcc:

"From small acorns do large acorns grow. The contents of the website (i.e. a proposal arguing for the existence of an internal evolutionary mechanism) have been sufficient to earn an invitation to join the evolutionary-psychology egroup (http://groups.yahoo.com/group/evolutionary-psychology), a reference in a foreign press (http://www.hkz.hr/244/24415.htm, acceptance for inclusion in various science directories, a steady trickle of people joining a mailing list, etc., etc.."

Circumcision is a physical trauma.

Jorolat

[choosybeggar]

Originally posted by jorolat
This results in any new proposal being met with a negative knee-jerk reaction as dogma (which they can never know for themselves anyway) is regurgitated.


Jorolat,

Many on this board find the battle against dogmatic views to be a worthwhile venture. But please consider that many widely held beliefs are actually correct. The notion that water is essential for all life on this planet for instance.

Consider also past battles against accepted beliefs. Many do not succeed, but those which do share (at least) two features in common: the phenomenological evidence is compelling and a mechanism is proposed to explain the phenomenon.

A recent victory in the fight against dogma was the dramatic overturn of the notion that bacteria were not involved in the pathogenesis of peptic ulcer disease. The orthodox view was that oversecretion of acid and a breakdown of the stomach's protective lining were the overriding factors. Treatments (and multibillions in R&D and drug sales) were all directed at the putative cause, ignoring the bacterium that we now know to cause this disease. The bacterium is H. pylori. The establishment did not pay attention to this little bug until an Austrailian reaseacher, Barry Marshall, drank an H. pylori culture and developed severe peptic ulcer disease.

The anti-dogmatists won this battle. They had compelling evidence (drinking culture resulting in disease plus a good deal of other data) and their mechanism (bacteria cause a disease) was not out of left field. Don't underestimate the importance of a sensible mechanism to explain an observed phenomenon.

In the case for Lamarkian evolution, while the data may be lacking, I would argue that the lack of a plausible mechanism is the larger issue. Consider the rat experiment you cite. Somehow the somatic tissue of the rat needs to inform its germ cells that there had been a change. Assuming we're discussing heritable traits in the context of the gene theory of inheritance, this is a bitter pill to swallow. The behavioral change observed presumably is mediated by changes in the the rat's nervous system. These changes needn't be at the genetic level, but they could be. Somatic mutation is argubably rare in most tissues, but it does occur and I will grant you that it is a plausible (though unlikely) mechanism to explain the neurological dysfunction of the adult rats. However, to see the trait in the offspring, the somatic tissue needs to somehow inform the germ tissue of the change. Here is where the mechanism breaks down. We know of no way in which this can occur. Not that it can't, but that it is way outside of our current notion of the generation of germ cells. Would brain cells migrate to the testes and differentiate into germ cells? I've heard of the genital mode of thinking, but brain tissue in the testes?:)

Maybe you would propose a non-genetic mode of inheritance, but this would take Lamarkianism even further afield, reducing the likelihood of acceptance of this notion by the establishment.

In summary, while compelling phenomenological evidence can ultimately prevail, a plausible mechanism makes wacky phenomenology more palatable.

Originally posted by PosterChild
I think the fact that these experiments haven't been repeated in a controlled fashion is almost a statement in itself. In fact, I think these experiments have been performed, but didn't show the changes hoped for. (Think Duesberg & AIDS, or Lamark himself, or cold fusion, or Choosybeggar's PhD work.)

I'll get you PosterChild!!

[PosterChild]

Originally posted by jorolat

Individual ducks would survive, individual ducks would reproduce, individual ducks would fare better than others. Perhaps an analogy will convey what I mean:

Imagine driving past a golf course just after it has begun to rain and seeing a number of people holding umbrellas. If you return an hour later and it is still raining then you might see more umbrellas in evidence.

The question to be asked is "has the population of
umbrella-carriers grown or have a number of people found a
similar solution to a similar problem?".

What applies to people also applies to ducks, the statement "populations evolve, not individuals" shouldn't be taken literally.

Lastly, just because a mechanism lies external to the individual does not make it "supernatural." How can you make this logical leap? Population level, species level, biosphere level, how are these not all part of nature?

If a mechanism is not part of natural life then surely by definition it must be supernatural?. Populations are made up of individuals etc. etc..

Jorolat


Would you explain the "internal evolution" you talk about? I've been trying to come up with some plausible mechanisms that an individuals adaptation can be passed on to it's offspring. Choosybeggar has enunciated, IMHO, 1 or 2 prime sticking points- how to transmit the information to the next generation. Are you proposing a non-genetic form of information? Mothers do pass on non-genetic information that orients the developing zygote, and non-DNA info in expressed mRNA to kick start the little guy, but I'm not sure if that'd do what you're talking about.

Also, the eggs in the mother are already formed (in the first experiment) before the mother has adapted, so they seem like a dead end in terms of passing on the adaption.

The second sticking point (for me) is the "motivation" behind the evolution. My understanding of evolution, is that "populations evolve, not individuals" should be taken literally. Darwinian evolution postulated that change does not happen in response to the environment. It happens randomly and then selection occurs.
Lamarkian evolution seems to suggest almost a consciousness. The animal is faced with a challenge -> it changes to meet the challenge -> it changes something to pass that change to it's offspring. Darwinian evolution gets around that by showing that the change genetic, and part of the animal before the environmental challenge.

If you can clarify those points, you'd go a long way to establishing this as a defensible hypothesis.

PC

P.S.- You do accept that Darwinian evolution, based on random genetic changes and 'natural' selection, does occur, right?

[Chronos]

jorolat, you're looking for information on these experiments, you say? That's easy: Do the experiments yourself. Catepillars are not hard to get ahold of, and elementary-school students routinely raise them. Try it, and see what happens.

[Live Octopus]

Originally posted by jorolat
On the other hand my belief that life is individual means that 4 out of 19 can be as significant as 400 out of 2000.


Unfortunately, the possibility of significance has to do with statistics, not evolution. Any high school statistics student will tell you that 19 isn't a very good sample size, and certainly isn't good enough to draw a conclusion about a population of millions.

[jorolat]

Originally posted by choosybeggar
Originally posted by jorolat
This results in any new proposal being met with a negative knee-jerk reaction as dogma (which they can never know for themselves anyway) is regurgitated.


Jorolat,

Many on this board find the battle against dogmatic views to be a worthwhile venture.

Where possible I try and avoid such battles particularly when they are a function of the conditioning a person has undergone during the "training" phase of their lives. It is always refreshing, however, when dogma is overturned as in the example that you described.

Additional to dogma is the problem of perception and how different people can look at the same data and come to totally different conclusions.

The "pop evolution" book "Evolution: A Theory In Crisis" (M. Denton), for example, contains a subset of the cytochromes percent sequence matrix taken from "The Atlas of Protein Structure and Function" (Dayhoff).

Unable to find a linear relationship for the values given Denton states, on a number of occasions, variations on the theme of "There is not a trace at the molecular level of the evolutionary transition from fish - amphibian - reptile - mammal". He does, however, refer to "the..strangely ordered aspect to the pattern of the molecular distribution".

Looking for an integrated function immediately reveals the reverse fibonacci series. The occasional "surfacing" of the series in this way would be what one might expect when looking for evidence of an internal evolutionary mechanism based on homeostasis.

Of course the database is very small but for the purpose of this post the point is the series is there for the values given.

In the above Denton and I interpret the data in different ways and I'm sure conventional theory does so in yet a third. The data, however, remains the same for all three.

In the case for Lamarkian evolution, while the data may be lacking, I would argue that the lack of a plausible mechanism is the larger issue.

I am not arguing the case for Lamarckian evolution as such but for the possible existence of an internal evolutionary mechanism based on an extension to homeostasis.

This mechanism is described at http://www.geocities.com/jorolat/TEM.html, is very simple in operation, and shows, as only one example, how it could account for the Baldwin Effect in a non-Larmarckian manner - i.e. it is an indirect mechanism that makes no suggestion of there being any direct link between somatic and germ cells (the "Weismann Barrier") or any change in the somatic cells themselves.

Jorolat

[Phil Saoud]

[i]

I do have a recollection of reading about Kammerer but whatever book it was in is not, unfortunately, immediately to hand. Thanks for reminding me of him though!.



[/B]

I believe the book you are refering to is "The Case of the Midwife Toad" by Arthur Koestler. Koestler wrote a fair amount about Darwin and Lamark with the general view that natural selection and random mutation fall short of fully explaining the evolutionary process.

I'm not an evolutionary biologist but I know enough arithmatic to see Koestler's point. However, as this message board shows, there are many closed minds on the topic.

[jorolat]

Originally posted by PosterChild

Would you explain the "internal evolution" you talk about? I've been trying to come up with some plausible mechanisms that an individuals adaptation can be passed on to it's offspring. Choosybeggar has enunciated, IMHO, 1 or 2 prime sticking points- how to transmit the information to the next generation.

The basic concept of the proposed mechanism can be found at: http://www.geocities.com/jorolat/TEM.html

I would reproduce the relevant sections here but pics can't be posted. As "a picture can paint a thousand words" I hope you are sufficiently interested to visit the site.

I can, however, try and answer some of the points you've made but they will make more sense if you've read the info at the website (skip the intro & go straight to "The post-Notochord Mechanism", its only a couple of pages long).

Also, the eggs in the mother are already formed (in the first experiment) before the mother has adapted, so they seem like a dead end in terms of passing on the adaption.

The homeostatic nature of the proposed mechanism means that it can be tested for without knowing how it is internally "implemented".

In reply to the above point, however, signalling pathways are already known to exist that lead from the area of the brain indicated for post-notochord organisms to the nuclei of sex cells. The eggs are formed but "communication" is ongoing.

[QUOTE]The second sticking point (for me) is the "motivation" behind the evolution.[QUOTE]

Briefly homeostasis means maintaining equilibrium or staying the same.

Transient disruptions of equilibrium in the area of the brain indicated are integrated over time. When existing thresholds are exceeded (either "positively" or "negatively") then evolutionary changes are triggered in a direction restoring equilibrium (and which may take "several" generations to achieve - perhaps via vertically transmitted retrotransposons).

There is, therefore, no motivation for evolution beyond that of maintaining equilibrium. A shark would be an example of an organism whose existing thresholds haven't been exceeded to the degree that further changes have occured while the rats on the turntable appear to be organisms where they have - particularly as the offspring were born with flicking heads AND flickering eyes.

[QUOTE]Lamarkian evolution seems to suggest almost a consciousness.[QUOTE]

As a person in a coma shows "consciousness" is not even needed for biological survival. It is in the areas of the brain that maintain survival (through homeostasis) that the mechanism is proposed to exist.

How the proposed mechanism could account for the common origin of the pentadactyl pattern also shows that "consciousness" is not a factor (http://www.geocities.com/jorolat/evocompa.html).

A final comment: Bacteria have the astonishing ability to replicate, to "create" copies of themselves each independently alive.

To suggest that the single cell common ancestor may have had, under very specific circumstances, what is arguably the lesser ability to evolve is not entering the realms of science fiction. Or that is how I feel anyway (smile).

Jorolat

[Lemur866]

I always get suspicious when people with no training in biology assert that scientists are afraid to challenge the dogma in their fields.

This is not true. The only way to make a name for yourself as a scientist is to challenge and overturn established ideas. Scientists are not shy about challenging accepted models. It's just that new models that are more succesful than the old are very hard to fashion. And this is as it should be, if it were easy to prove the old theory wrong it would ALREADY have been proven wrong long ago.

So anyone who asserts a conspiracy of scientists to ignore the truth is automatically placed in my "ignore file". They are so far out of touch with the reality of scientific work that their ideas may be ignored without further thought.

Yes, they laughed at Galileo, they laughed at the Wright Brothers, they laughed at Einstein. But they also laughed at Bozo the Clown. So just because all scientists ignore and belittle your ideas does NOT make your ideas right. Perhaps all the other scientist are actually correct, and YOU are the one with the mistaken ideas. Something to consider, no?

[cainxinth]

hopefully someone already posted this- i couldnt stomache to sort through any more posts after reading the first dozen or so. both those experiments are utterly impossible. the only way the offspring of those subjects could inherit those behaviors would be if a) they were trained by the parent or by the researchers (which was never mentioned in the original post) or b) the genes of the offspring mutated and adaped the new behavior in 1 generation! (which is impossible because evolutionary adaptation takes hundreds of generations).

All you people do is babble amongst yourselves -- your reply should pertain to the original goddamn post.

[cainxinth]

p.s. jerolat- you are a sad, seriously misguided person.

[PosterChild]

Let me see if I've got this right...
The Area of Natural Equilibrium is in the mid-brain. It receives signals that alter equilibrium of something, and it modifies that something to bring it back to equilibrium genetically. In the process it sends a signal to the germ cells that replicates the genetic change.
The web site you mention also seems to suggest that evolution doesn't occur as traditionally understood. It claims that we lost our tail, because the AONE removed because we weren't using it. (Just curious, but do you feel that makes more sense than natural selection?)
ok, here goes.
1. Does the AONE mean that this "Baldwin Effect" only occurs in animals with this type of brain?
2. They give descriptive examples, but the tail thing is very adequately explained by Darwinian evolution, and the bicycle thing seems to disprove it. People have been riding bicycles for generations, yet we still have to go through training.
It kind of reminds me of the syphon thread, with people proposing all kinds of thought experiments instead of just making a syphon for themselves.
3. The mechanims for transmitting the change to the germline doesn't make sense. The paper in Science explains how retrotransposons is another way to cause random (i.e.- non-directed) genetic changes that are then selected for. This is straight Darwin.
Signalling pathways from outputs of the AONE into the genomes of specific physically remote cells are known to exist as is a molecular mechanism, recently discovered in mammals, of a type that would also be necessary: "Experiments performed at the University of Maryland Medical Center have revealed a molecular mechanism that may be a significant driver of evolution in humans and other mammals. Certain retrotransposons - bits of DNA able to copy themselves from one region of the genome to another - are able to pick up flanking genetic sequences and then insert themselves and the tag-along DNA at new locations". Connect signalling pathways with such molecular mechanisms and the proposed action of the AONE on the genome is entirely possible
They mention that there are signalling pathways from the AONE to the genomes of remote cells, but as far as I know that's totally false. If you can show any signalling pathway that leads to directed genomic alteration in germline cells, I would be fascinated to learn of it.
I suppose I should say that I do know of one example of the genome being altered by signalling from the cell's surface. It occurs during an immune response, but the signal starts random mutations and the cells that are have them face selection just as natural selection.
Now that I think of it, how come we don't pass on the phenotypic adaptations that occur to allow us to fight of infections? How come our offspring aren't protected by our exposure and adaptation to infection. There are bugs that we have been fighting for many many generations, and yet we still have to develop immunity from scratch.
I'm trying to be open minded:eek:, all ideas need to be debated, and adapted. Can you think of a make or break experiment that can be done or has been? I guess I should ask how attached are you to this. Would you be able to accept that it wasn't true?
PC

P.S.- Do you feel that Darwinian evolution occurs?

[PosterChild]

Originally posted by cainxinth
p.s. jerolat- you are a sad, seriously misguided person.

Definitely a helpful & constructive post.

[jorolat]

Originally posted by Chronos
jorolat, you're looking for information on these experiments, you say? That's easy: Do the experiments yourself. Catepillars are not hard to get ahold of, and elementary-school students routinely raise them. Try it, and see what happens.

It simply isn't feasible at this point in time to consider repeating the caterpillar experiment.

From the perspective of a still developing project, and despite any potential they may hold, the experiments occupy a relatively minor place and primary sources would be quite adequate for my current needs.

Jorolat

[Chronos]

From the perspective of a still developing project, and despite any potential they may hold, the experiments occupy a relatively minor place and primary sources would be quite adequate for my current needs.Saying that the experiments occupy a minor place is tantamount to saying that you're not doing science. If the experiments are not replicated, then they and reports of them mean exactly nothing. My options at this point are to close this thread, or to leave it open for people to ridicule you: Keeping it open would serve no other purpose. I hope you understand my decision.