Jump to content


Photo

Natural Selection-thread Closed


  • This topic is locked This topic is locked
62 replies to this topic

#1 John Paul

John Paul

    Member

  • Banned
  • PipPipPip
  • 241 posts
  • Age: 44
  • Muslim
  • Creationist
  • Maynard, Massachusetts

Posted 26 July 2005 - 06:48 AM

Natural selection is evolutionists magic bullet. But what is natural selection? Survival of the fittest?

Who are the fittest? Those who survive to prodice the most offspring.

Who survives to produce the most offspring? Why the fittest of course!

Totally useless. And science pretty much agrees with me:

The Strength of Natural Selection in the Wild

That article is in response to J.G. Kingsolver et al entitled The Strength of Phenotypic Selection in Natural Populations, which was published in the March 2001 issue of The American Naturalist.

In populations over 1000 NS is virtually non-existent. In lesser populations NS accounts for only 16% of the allele frequency change leaving 84% of the change not explained by NS at all.

#2 Guest_Calipithecus_*

Guest_Calipithecus_*
  • Guests

Posted 26 July 2005 - 08:57 AM

But what is natural selection? Survival of the fittest?

View Post

That phrase was coined by Herbert Spencer. Darwin didn't like it, and accepted it only at Wallace's urging.

Totally useless. And science pretty much agrees with me

In the interest of honest, civil dialogue, let's be clear about who is saying what. The folks at Discovery Institute have interpreted the results of a study by J.G. Kingsolver et al. You agree with their interpretation.

In populations over 1000 NS is virtually non-existent.

Before this turns into a game of 'Chinese Whispers', let's quote directly from the article you linked:

It is when sample sizes pass beyond samples of 1000 that results become far more difficult to accommodate, for under these circumstances, Kingsolver reported, both linear and quadratic selection were virtually non-existent.

Better yet, we could go directly to the source material itself: http://kingfish.coas...llselection.pdf.

I'm still perusing that article, and I could use a little help figuring out how the DI folks reached the above conclusion. I think this passage is relevant:

-----------------------------------------
"Another important feature of the studies taken collectively is their low statistical power. Most of the studies were not replicated in either time or space. In addition, the sample size associated with estimates is quite low, with a median sample size across studies of only Np 134 for the estimates. The median sample size among estimates is even lower (Np 92), implying that studies with smaller sample sizes tended to report relatively more estimates of selection. As a result, standard errors associated with the estimates are quite large relative to the magnitude of selection, and most studies lacked the statistical power to detect selection of average magnitude. Thus, only 25% of the linear gradients and differentials and only 16% of the quadratic gradients and differentials were individually significant at the P p .05 level. Moreover, nearly all studies estimated multiple selection gradients or differentials in each experiment, and very few corrected for multiple significance tests (e.g., by adjusting the critical a to maintain an appropriate level of experiment-wide Type I error. For example, a typical study that estimated linear and quadratic gradients on four traits from a single longitudinal experiment would generate 20 individual significance tests. As a result, the results reported here almost certainly overestimate the frequency of statistically significant selection and overestimate the power of these studies to detect selection of average magnitude. It is sobering that,for sample sizes exceeding ~103, most estimates of linear and quadratic selection gradients cluster between 0.1 and 0.1: our most powerful studies indicate that selection is weak or absent."
-----------------------------------------

Pretty heady stuff. My interpretation of what Kingsolver is saying here (in simplest form) is that most available studies are error-prone due primarily to small sample size, a conclusion which the Discovery Institue folks twist to make it look like Kingsolver is saying that selection does not exist. It's not the same thing.

#3 The Debatinator

The Debatinator

    Member

  • Veteran Member
  • PipPipPip
  • 198 posts
  • Age: 20
  • Christian
  • Young Earth Creationist
  • Chicago, Illinois

Posted 26 July 2005 - 09:27 AM

Some logic I don't get. I mean it might sound like science but things like...

Creationist: How did animals develop male and female?

Evolutionist: The ones that did develop male and female passed on their genes and blah blah blah...

Or.

Creationist: How did animals develop brains? Lungs? Blood? Kidneys? Immune systems?

Evolutionist: The ones that didn't have those didn't pass on their genes but the ones that did passed on their genes.

Does anyone know where I'm coming from?

#4 Guest_Calipithecus_*

Guest_Calipithecus_*
  • Guests

Posted 26 July 2005 - 11:52 AM

Creationist: How did animals develop male and female?
Evolutionist: The ones that did develop male and female passed on their genes and blah blah blah...

View Post

The origins of S@xual reproduction are not well understood. In his book, The Cooperative Gene, Mark Ridley compellingly argues that it is best explained as an error-correcting mechanism. It is worth noting that the vast majority of organisms (the procaryotes) did not adopt this approach, presumably because their simpler cell structure, being more tolerant of error, did not make S@xual reproduction advantageous; another way of looking at it is that S@xual reproduction opens the door for the development of more complex structure. Though that discussion is interesting, it gets rather involved, and may be somewhat of a tangent to this thread. It begins with recognition that selection can operate at the level of the genotype as well as at the level of the phenotype, with snippets of DNA competing against one another for better representation on the strand whether that leads to more competitive organisms or not.


Evolutionist: The ones that didn't have those didn't pass on their genes but the ones that did passed on their genes.

Or, more accurately: the ones that didn't have those (or that had them in lesser degree) passed on fewer copies of their genes than those that did. Can you be specific as to what it is about the fundamental logic of this proposition that bothers you?

#5 futzman

futzman

    Junior Member

  • Member
  • PipPip
  • 15 posts
  • Age: 50
  • no affiliation
  • Agnostic
  • Tulsa, OK

Posted 26 July 2005 - 12:01 PM

Pretty heady stuff.  My interpretation of what Kingsolver is saying here (in simplest form) is that most available studies are error-prone due primarily to small sample size, a conclusion which the Discovery Institue folks twist to make it look like Kingsolver is saying that selection does not exist.  It's not the same thing.

View Post


Boy, I'd have to agree with you on this point. I wouldn't probably even read a study of "low statistical significance" unless the conclusions were so obvious to not need statistics. That doesn't sound like the case in this study, however.

#6 chance

chance

    Veteran Member

  • Banned
  • PipPipPipPip
  • 2029 posts
  • Age: 51
  • no affiliation
  • Atheist
  • Australia

Posted 26 July 2005 - 01:40 PM

Natural selection is evolutionists magic bullet. But what is natural selection? Survival of the fittest?

Who are the fittest? Those who survive to prodice the most offspring.

Who survives to produce the most offspring? Why the fittest of course!

Totally useless. And science pretty much agrees with me:

View Post


Nope that is the correct definition, from the DI link you provided

and survival, mating success or fecundity typical measure of fitness.

Fitness is reproductive success.

#7 The Debatinator

The Debatinator

    Member

  • Veteran Member
  • PipPipPip
  • 198 posts
  • Age: 20
  • Christian
  • Young Earth Creationist
  • Chicago, Illinois

Posted 26 July 2005 - 03:07 PM

The origins of S@xual reproduction are not well understood.  In his book, The Cooperative Gene, Mark Ridley compellingly argues that it is best explained as an error-correcting mechanism.  It is worth noting that the vast majority of organisms (the procaryotes) did not adopt this approach, presumably because their simpler cell structure, being more tolerant of error, did not make S@xual reproduction advantageous; another way of looking at it is that S@xual reproduction opens the door for the development of more complex structure.  Though that discussion is interesting, it gets rather involved, and may be somewhat of a tangent to this thread.  It begins with recognition that selection can operate at the level of the genotype as well as at the level of the phenotype, with snippets of DNA competing against one another for better representation on the strand whether that leads to more competitive organisms or not. 
Or, more accurately: the ones that didn't have those (or that had them in lesser degree) passed on fewer copies of their genes than those that did.  Can you be specific as to what it is about the fundamental logic of this proposition that bothers you?

View Post



No no no, I recognize the idea that the ones that weren't developed enough died off or became much fewer and what not but the ones that did develop those up the line must have come from something that was more defective than them.

#8 Guest_Aristarchus_*

Guest_Aristarchus_*
  • Guests

Posted 26 July 2005 - 03:58 PM

That article is in response to J.G. Kingsolver et al entitled The Strength of Phenotypic Selection in Natural Populations, which was published in the March 2001 issue of The American Naturalist.

View Post


This is a paper on micro-evolution. They even use that in their keywords. Is anyone questioning that this is possible? It is easy enough to produce. Go out and shoot all the birds of a species with short beaks and the next generation will have longer beaks. Or just select your breeding stock accordingly.

The question this paper addresses is "how strong is the selection pressure and how large are the phenotypic changes in the real world?" Reviewing a collection of studies the author draws the following conclusion

"One consistent pattern that emerges from our analyses is
that the distribution of selection strengths is approximately
exponential (figs. 3–5, 8, 9). The median magnitude of
linear selection gradients in our database was FbF p.
There are two interesting consequences of this ex-0.16
ponential distribution. First, there is a long “tail” of values
indicating that very strong directional selection (FbF 1)
may occur. Second, directional selection on most traits0.5
and in most systems is quite weak."

In other words, sometimes you get quite significant movement in the phenotype, but in most cases the movement is rather small.

This is not a problem for evolutionary theorists that expect significant changes to occur over millions of years with mostly insignificant changes when limited to the last 50 years.

I see this as a problem only if you are a young earther trying to get all the species and all the variation we see on the planet from the descendents of just a few thousand species that fit on the Ark - and then to get all that change to occur in just 6000 years. The paper suggests that most change doesn't happen all that fast.

#9 Guest_Calipithecus_*

Guest_Calipithecus_*
  • Guests

Posted 26 July 2005 - 04:09 PM

I recognize the idea that the ones that weren't developed enough died off or became much fewer and what not but the ones that did develop those up the line must have come from something that was more defective than them.

View Post

Your choice of words there suggests that you may be taking on board some dubious assumptions, including some that were rejected by evolutionary theorists long ago (notions about evolution representing 'progress' being among the first to come to mind).

Fitness, in addition to being measured in reproductive success, is a concept which can be rendered meaningful only within the context of current, local conditions. What works beautifully in one place (or at one time) becomes 'defective' in the instant that it arrives somewhere else (think of a polar bear in the Sahara). Darwin's resistance to the phrase: "survival of the fittest" reflects an intuitive grasp of this fact.

#10 Guest_92g_*

Guest_92g_*
  • Guests

Posted 26 July 2005 - 05:59 PM

Your choice of words there suggests that you may be taking on board some dubious assumptions, including some that were rejected by evolutionary theorists long ago (notions about evolution representing 'progress' being among the first to come to mind).


So if we go up the supposed evolutionary tree, from a single celled organism, to life as we know it, it's not fair to say there was a progression?

Why exactly did they abandon that idea?

Terry

#11 chance

chance

    Veteran Member

  • Banned
  • PipPipPipPip
  • 2029 posts
  • Age: 51
  • no affiliation
  • Atheist
  • Australia

Posted 26 July 2005 - 06:56 PM

So if we go up the supposed evolutionary tree, from a single celled organism, to life as we know it, it's not fair to say there was a progression?

Why exactly did they abandon that idea?

Terry

View Post


It’s not fair because ‘progression’ is subjective, (progression of what attribute?).

E.g if intelligence were the measure, one could draw a tree with man at the top. However if surviving rapidly changing environments were the measure, bacteria would fair rather better than most life forms.

The best representative diagrams are those that show all current life residing equally at the top (most recent).

I’m not sure the idea of having man at the top of the tree was ever in vogue from a Darwinian purist’s POV. (I can still remember those diagrams in school with man above apes, above the other mammals, above reptiles etc) It seems to have happened by virtue of having a high opinion of ourselves, coupled with some misunderstanding.

#12 John Paul

John Paul

    Member

  • Banned
  • PipPipPip
  • 241 posts
  • Age: 44
  • Muslim
  • Creationist
  • Maynard, Massachusetts

Posted 27 July 2005 - 06:17 AM

Nope that is the correct definition, from the DI link you provided  Fitness is reproductive success.

View Post



I know fitness is reproductive success- that is what I said in my OP. That is what makes NS useless- there is no way to know which organisms are the most fit just by looking at them. You have to wait to check their offspring before making any determiniation on fitness. And even then about 84% of the alleles are not due to NS but some other factors such as chance & luck- which are not heritable traits.

Cal:
Pretty heady stuff. My interpretation of what Kingsolver is saying here (in simplest form) is that most available studies are error-prone due primarily to small sample size, a conclusion which the Discovery Institue folks twist to make it look like Kingsolver is saying that selection does not exist. It's not the same thing.


DR Berlinski did not say that selection does not exist. Not even close. He did show that the paper demonstrates NS isn't what is was jacked up to be. But we already knew that from pre-Darwinian papers on NS. The papers that Darwin used in an attempt to make someone else's idea his own.

#13 Guest_Calipithecus_*

Guest_Calipithecus_*
  • Guests

Posted 27 July 2005 - 06:31 AM

DR Berlinski did not say that selection does not exist. Not even close.

View Post

Thanks for straightening me out on that. I think I traced the source of my confusion to this passage:

"Considering the fundamental role of both linear and quadratic selection in population genetics and in popular accounts of Darwin’s theory, one of those unresolved issues may well be whether natural selection exists to any appreciable extent, and if it does, whether it plays any real role in biological change altogether."

#14 The Debatinator

The Debatinator

    Member

  • Veteran Member
  • PipPipPip
  • 198 posts
  • Age: 20
  • Christian
  • Young Earth Creationist
  • Chicago, Illinois

Posted 27 July 2005 - 10:05 AM

Your choice of words there suggests that you may be taking on board some dubious assumptions, including some that were rejected by evolutionary theorists long ago (notions about evolution representing 'progress' being among the first to come to mind).

Fitness, in addition to being measured in reproductive success, is a concept which can be rendered meaningful only within the context of current, local conditions.  What works beautifully in one place (or at one time) becomes 'defective' in the instant that it arrives somewhere else (think of a polar bear in the Sahara). Darwin's resistance to the phrase: "survival of the fittest" reflects an intuitive grasp of this fact.

View Post



I thought part of evolution was reaction to the environment. I might be wrong. That's why I'm in training :rolleyes: .

#15 John Paul

John Paul

    Member

  • Banned
  • PipPipPip
  • 241 posts
  • Age: 44
  • Muslim
  • Creationist
  • Maynard, Massachusetts

Posted 27 July 2005 - 12:48 PM

From the book Why is a Fly is not a Horse? by prominent Italian geneticist Giuseppe Sermonti (page 13):

"Natural selction could perhaps be invoked as a mechanism for the survival of species. But the claim that natural selection is creative of life, of life's essence and types and orders, can only leave us dumbstruck. Natural selection only eliminates, and its adoption of a mechanism of origin is like explaining "appearance" by "disappearance"."

He goes on to say what others before Charles Darwin said about NS- that it is a conserving force. It eliminates the marginal and out-of-bounds and keeeps the norm.

#16 John Paul

John Paul

    Member

  • Banned
  • PipPipPip
  • 241 posts
  • Age: 44
  • Muslim
  • Creationist
  • Maynard, Massachusetts

Posted 27 July 2005 - 01:02 PM

Thanks for straightening me out on that.  I think I traced the source of my confusion to this passage:

"Considering the fundamental role of both linear and quadratic selection in population genetics and in popular accounts of Darwin’s theory, one of those unresolved issues may well be whether natural selection exists to any appreciable extent, and if it does, whether it plays any real role in biological change altogether."

View Post


As long as everyone understands that whether it (natural selection) has any real role in biological change is not the same as saying it doesn't exist, then we are OK. That is the debate- is NS the "magic bullet" evolutionists insist it is or is it the conservative force reality demonstrates it is?

As for blind mutations (ie random) Dr.Sermonti says:
"To say that blind mutations are the driving priciple of the world, and to rely on the rare fortunate mistake, is a poor resource, quite apart from the fact that transgressions of the kind needed by Darwinian evolution have never been documented."

#17 chance

chance

    Veteran Member

  • Banned
  • PipPipPipPip
  • 2029 posts
  • Age: 51
  • no affiliation
  • Atheist
  • Australia

Posted 27 July 2005 - 01:40 PM

I know fitness is reproductive success- that is what I said in my OP. That is what makes NS useless- there is no way to know which organisms are the most fit just by looking at them.


Quite correct, you can’t determine by looking, which one out of many, is fitter than the other. Because what you see when you look at something is it’s size, weight, speed, colour, etc. While these outward traits have some bearing on the individuals capability to survive and win a mate, it wont be every factor.


You have to wait to check their offspring before making any determiniation on fitness. And even then about 84% of the alleles are not due to NS but some other factors such as chance & luck- which are not heritable traits.

View Post



Correct again, once the parents have finished breeding, you could determine their success by counting the number of offspring that also made it to reproductive age and produced offspring.

Natural selection is a description of a process not a method of measuring fitness, which is what you seem to be implying (false dilemma).

#18 chance

chance

    Veteran Member

  • Banned
  • PipPipPipPip
  • 2029 posts
  • Age: 51
  • no affiliation
  • Atheist
  • Australia

Posted 27 July 2005 - 01:52 PM

"Natural selction could perhaps be invoked as a mechanism for the survival of species. But the claim that natural selection is creative of life, of life's essence and types and orders, can only leave us dumbstruck. Natural selection only eliminates, and its adoption of a mechanism of origin is like explaining "appearance" by "disappearance"."


Evolution does not create life.

Not sure what of life's essence means?

Re-Types and orders, speciation I presume? Or ‘micro evolution’? If a trait is favourable to natural selection, and the beneficiary become dominant, has that not ‘created’ from it’s POV by eliminating the losers?
That paragraph from Why is a Fly is not a Horse is a semantic argument at best. If your eliminating your also creating.

#19 John Paul

John Paul

    Member

  • Banned
  • PipPipPip
  • 241 posts
  • Age: 44
  • Muslim
  • Creationist
  • Maynard, Massachusetts

Posted 27 July 2005 - 02:22 PM

QUOTE(John Paul @ Jul 27 2005, 11:17 PM)
I know fitness is reproductive success- that is what I said in my OP. That is what makes NS useless- there is no way to know which organisms are the most fit just by looking at them.

chance:
Quite correct, you can’t determine by looking, which one out of many, is fitter than the other. Because what you see when you look at something is it’s size, weight, speed, colour, etc. While these outward traits have some bearing on the individuals capability to survive and win a mate, it wont be every factor.


Which is what I have been saying. The factors other than those outward traits are not heritable and far outweigh those that are.



QUOTE
You have to wait to check their offspring before making any determiniation on fitness. And even then about 84% of the alleles are not due to NS but some other factors such as chance & luck- which are not heritable traits.

chance:
Correct again, once the parents have finished breeding, you could determine their success by counting the number of offspring that also made it to reproductive age and produced offspring.


IF NS is to habe ANY effect at all one has to consider the reproductive success of all generations. And when that is done the best we get is oscillating allele frequencies. Which is not what is to be expected if NS was the "magic bullet" evolutionists want us to believe it is.

chance:
Natural selection is a description of a process not a method of measuring fitness, which is what you seem to be implying (false dilemma).


NS is a description of a conserrving process which is quite the opposite of what evolutioniusts require of it.

QUOTE(John Paul @ Jul 28 2005, 05:48 AM)
"Natural selction could perhaps be invoked as a mechanism for the survival of species. But the claim that natural selection is creative of life, of life's essence and types and orders, can only leave us dumbstruck. Natural selection only eliminates, and its adoption of a mechanism of origin is like explaining "appearance" by "disappearance"."

chance:
Evolution does not create life.


I know that. The quote was for Cal who appeared to say otherwise in another thread.

If you are eliminating the marginal you are conserving the norm. The bottom line is science has shown NS to be a conserving force and random mutations a bankrupt source. Yet people like you believe that these two, when combined, can do things that can't be verified via experimentation. What is the difference between that and a miracle?

#20 Guest_Calipithecus_*

Guest_Calipithecus_*
  • Guests

Posted 27 July 2005 - 02:39 PM

As long as everyone understands that whether it (natural selection) has any real role in biological change is not the same as saying it doesn't exist, then we are OK.

View Post

A good understanding of that must have been what you were working toward when you said: "In populations over 1000 NS is virtually non-existent."

That is the debate- is NS the "magic bullet" evolutionists insist it is or is it the conservative force reality demonstrates it is?

I don't recall ever hearing a biologist refer to selection as a 'magic bullet'; that appears to be your term -- but I will continue to point out, as I have before, that regarding it as a 'force' is quite mistaken. The one thing your linked article included that I agree with completely is this statement: "Natural selection disappears as a biological force and reappears as a statistical artifact" (the disapearing and reappearing, of course, taking place only in the minds of those who never understood that this was the situation from the very beginning).

As for blind mutations: I'm still looking forward to you sharing your own thoughts on any of these subjects, but since you have chosen to stick with quote mining, I'd like to point out that the one you offer here is worthless. "To rely on the rare fortunate mistake, is a poor resource" is bald assertion. "To rely on the rare fortunate mistake, is a poor resource because [insert supporting arguments here]" would be an actual argument.




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users