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Author Topic:   Doesn't Natural Selection lead to Specified Complexity?
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 61 of 138 (616935)
05-25-2011 5:55 AM
Reply to: Message 58 by Dr Adequate
05-23-2011 5:46 AM


Re: Drift
Perhaps I now understand where my misunderstanding lies -- thankyou for that explanation.

I was focussing on adaptation but thinking of it as gene distribution within a population -- I know understand them to be different things.

I would still expect there to be some non-random element to drift though ... surely a purely random set of mutations would have no trend.

Oh wait though ... if population size was very small and then expanded I suppose that would have an effect ... but then only if the individuals with a specific non-adaptive mutation were the most prevalent breeders -- and there should be some reason for that.

By ignore drift I meant 'in the context of natural selection's capability for designing apparently specified entities' not ignore it as though it didn't exist.

I think the focuss on drift has led to a drift away from specified complexity NOT being a marker for intelligent design at all.


This message is a reply to:
 Message 58 by Dr Adequate, posted 05-23-2011 5:46 AM Dr Adequate has replied

Replies to this message:
 Message 62 by Dr Adequate, posted 05-25-2011 7:23 AM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 64 of 138 (617195)
05-26-2011 2:44 PM
Reply to: Message 63 by PaulK
05-25-2011 8:15 AM


Re: So: 'If it was designed intelligently then it is the product of intelligent design.'
It is the determinism of NS that makes the difference in evolution.

Given the SAME set of mutations, but a different set of selective pressures the result will be different -- regardless of drift.

So it is the selection that specifies the outcome.

I don't remember mixing drift in with NS -- I added it as a kind of offset.

Why is it a statistical inevitability that some non-selectable mutations will become fixed?

If a mutation is purely random and not subject to selective pressure, why would it appear more than others?


This message is a reply to:
 Message 63 by PaulK, posted 05-25-2011 8:15 AM PaulK has replied

Replies to this message:
 Message 66 by PaulK, posted 05-26-2011 2:51 PM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 65 of 138 (617197)
05-26-2011 2:50 PM
Reply to: Message 62 by Dr Adequate
05-25-2011 7:23 AM


Re: Drift
I think I see what I have been missing -- thankyou.

I was missing the fairly obvious point that the variants of a particular allele are mutually exclusive within a single individual.


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Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 67 of 138 (617201)
05-26-2011 3:01 PM
Reply to: Message 66 by PaulK
05-26-2011 2:51 PM


Re: So: 'If it was designed intelligently then it is the product of intelligent design.'
Saw and replied to Dr. Addequate's post -- get that bit now.

If drift could cause the same outcome, despite selective pressure then natural selection is a non-starter as an explanation for diversification in biological systems.

I cannot implicitly include drift in natural selection while I am explicitly excluding it.

I have also said that I segregate genetic mutation from all other events -- thus they are not included in my concept of environment -- they are included in my concept of genetic mutation.


This message is a reply to:
 Message 66 by PaulK, posted 05-26-2011 2:51 PM PaulK has replied

Replies to this message:
 Message 68 by PaulK, posted 05-26-2011 3:10 PM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 76 of 138 (619237)
06-09-2011 10:00 AM
Reply to: Message 68 by PaulK
05-26-2011 3:10 PM


Re: So: 'If it was designed intelligently then it is the product of intelligent design.'
PaulK writes:

quote:

If drift could cause the same outcome, despite selective pressure then natural selection is a non-starter as an explanation for diversification in biological systems.

You're wrong again. Just because drift COULD explain it, it doesn't mean that drift is a good explanation. Drift is not a good explanation for adaptions (but it is a warning against assuming that a feature is an adaption). We need selection to adequately explain what we observe, because drift is just too damned unlikely to come up with anything useful.

Peter writes:

Please note that I didn't suggest that drift was any kind of explanation for adaptation -- in fact what I said was that mutations which are operated on by natural selection must dominate adaptive changes ... to which you disagreed.

quote:

I cannot implicitly include drift in natural selection while I am explicitly excluding it.

Indeed, you should not. That is why I object to you doing so.

Peter writes:

I've said several times that I am NOT including drift in natural selection. I have specifically separated it out in fact.

quote:

I have also said that I segregate genetic mutation from all other events -- thus they are not included in my concept of environment -- they are included in my concept of genetic mutation.

I strongly suggest that you drop the idea of mutations directly causing drift to any significant extent - it's been explained to you why that is wrong often enough, by myself and Dr. Adequate.

Peter writes:

I have been focussing on mutation since I was attempting to discuss the way in which the 'process' of natural selection working on mutations can be seen to generate entities with apparently specified complexity.

I have, therefore, disregarded the case where no mutations occur.

In my simple, formulaic way I could write:

Gene_Distribution[k] = NaturalSelection(Environment[k-1], Gene_Distribution[k-1]) + Drift(Gene_Distribution[k-1])

k being some quanta of time.

This would cover, for example, Gallapogas (sp?) finches.

I was neglecting the effect of drift for the sole purpose of discussing the capability of natural selection to 'generate' specified complexity.

Edited by Peter, : I am very poor at formatting ....


This message is a reply to:
 Message 68 by PaulK, posted 05-26-2011 3:10 PM PaulK has replied

Replies to this message:
 Message 77 by Percy, posted 06-09-2011 10:09 AM Peter has replied
 Message 79 by PaulK, posted 06-09-2011 11:40 AM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 78 of 138 (619249)
06-09-2011 10:19 AM
Reply to: Message 77 by Percy
06-09-2011 10:09 AM


Re: So: 'If it was designed intelligently then it is the product of intelligent design.'
Hmmm ... see what you mean. I edited it a bit to try to help.

This message is a reply to:
 Message 77 by Percy, posted 06-09-2011 10:09 AM Percy has seen this message

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 80 of 138 (619299)
06-09-2011 11:55 AM
Reply to: Message 79 by PaulK
06-09-2011 11:40 AM


Re: So: 'If it was designed intelligently then it is the product of intelligent design.'
Please show me how I lumped drift and natural selection together when my psuedo code specifcally separates them.

I show natural selection to be a function of environment and 'genetics' and drift to be a function of 'genetics' alone.

In what precise way does that conflate them?

My original point was that the filter which is natural selection can lead to results that are indistinguishable from Specified Complexity ... making Specified Complexity fail as an indicator of intelligent design.


This message is a reply to:
 Message 79 by PaulK, posted 06-09-2011 11:40 AM PaulK has replied

Replies to this message:
 Message 81 by PaulK, posted 06-09-2011 1:48 PM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 82 of 138 (619510)
06-10-2011 6:29 AM
Reply to: Message 81 by PaulK
06-09-2011 1:48 PM


Re: So: 'If it was designed intelligently then it is the product of intelligent design.'
You've stated that, rather than explained that.

I posit natural selection as a function of environment and gene distribution and drift as a function solely of gene distribution.

That the environment includes everything that happens was intended to mean at the same level of abstraction as 'population'.

And I still don't really see what that disagreement has to do with the concept of natural selection generating specified complexity.


This message is a reply to:
 Message 81 by PaulK, posted 06-09-2011 1:48 PM PaulK has replied

Replies to this message:
 Message 83 by PaulK, posted 06-10-2011 8:07 AM Peter has replied
 Message 84 by Percy, posted 06-10-2011 8:08 AM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 117 of 138 (619927)
06-13-2011 10:27 AM
Reply to: Message 84 by Percy
06-10-2011 8:08 AM


Re: So: 'If it was designed intelligently then it is the product of intelligent design.'
Hopefully that was simply from a mis-reading of my post ... herein re-written with parenthesis:

(Natural selection is a function of environment and gene distribution) and (drift is a function of gene distribution)

... and I think I have more 'talking' to do about that ...


This message is a reply to:
 Message 84 by Percy, posted 06-10-2011 8:08 AM Percy has seen this message

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 118 of 138 (619928)
06-13-2011 10:33 AM
Reply to: Message 83 by PaulK
06-10-2011 8:07 AM


Re: So: 'If it was designed intelligently then it is the product of intelligent design.'
I didn't say that gene distribution can predict drift, merely that drift is functionally dependent upon it.

I place 'drift' in the position of the 'function' or 'process' acting upon 'gene distribution'.

so (and neglecting the NS part for this and only this point):

GeneDist[k] = drift(GeneDist[k-1])

I have NOT commented on exactly what drift is or is not ... and only included it as an offset in principle because you mentioned it. I was merely trying to show where it fit into my thinking, and why, for this discussion, I was neglecting it.

Determinism:

You do know what deterministic means, don't you?

You answered a question of mine previously in a manner which can only mean you accept that the process of natural selection is deterministic.

"complete and fully detailed" at the same level of abstraction as the population.


This message is a reply to:
 Message 83 by PaulK, posted 06-10-2011 8:07 AM PaulK has replied

Replies to this message:
 Message 120 by PaulK, posted 06-13-2011 12:30 PM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 119 of 138 (619929)
06-13-2011 10:38 AM
Reply to: Message 85 by SavageD
06-11-2011 4:38 PM


Re: Doesn't Natural Selection lead to Specified Complexity?
What I am actually trying to say is that the 'specified complexity' observed by IDists is, in fact, illusory.

Natural selection is capable of 'designing' systems to such a degree that they appear to have 'specifiec complexity'


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Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 121 of 138 (620112)
06-14-2011 7:48 AM
Reply to: Message 120 by PaulK
06-13-2011 12:30 PM


Drifting into drift.
Drift 'function':

As I have suggested before, the way I see it is that the 'process' of drift has far too many variables for us to model approriately.

It is, for example, inevitably affected by natural selection.

It is, by definition, not directly affected by environmental pressures on the population in question.

To justify excluding it from a discussion on the 'specifying'/'designing' power of natural selection I added it as an offset. I concede that this is a rather large simplification.

I consider it a distraction from the main point here.

Determinism:

So do you accept or reject 'universal determinism'? i.e. that what we see as random is actually the result of interactions too complex for us to comprehend.

Leaving us to model as best we can (with full knowledge that we are using a best fit rather than a precise model).


This message is a reply to:
 Message 120 by PaulK, posted 06-13-2011 12:30 PM PaulK has replied

Replies to this message:
 Message 122 by PaulK, posted 06-14-2011 11:44 AM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 123 of 138 (620155)
06-14-2011 12:56 PM
Reply to: Message 122 by PaulK
06-14-2011 11:44 AM


Re: Drifting into drift.
Good. So we can draw a line under determinism and move on then.

As for environment and drift:

It is and remains my understanding that drift is about gene frequency within a population changing over time for no particular reason -- or rather not in response to a specific stimulus.

I therefore regard it as a function purely of the gene distribution from the previous time quanta.

It is affected by which genes (should I be saying alleles?) get into the gametes, and which gametes get into the next generation.

There are, quite possibly, factors which affect this, but it appears to be a random process.

Drift will affect small populations most, having the effect of reducing allele diversity (within the population).

So I now say that a reasonable way to view it is:

GeneDist[k] = NaturalSelection(Env, PopulationSize[k], GeneDist[k]) + Drift(PopulationSize[k-1],GeneDist[k-1])

Which is a little different (thanks for the thought processes being triggered) but does NOT impact my original post:

Natural Selection can produce entities that appear to have Specified Complexity.


This message is a reply to:
 Message 122 by PaulK, posted 06-14-2011 11:44 AM PaulK has replied

Replies to this message:
 Message 124 by PaulK, posted 06-14-2011 1:09 PM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 125 of 138 (620850)
06-21-2011 11:23 AM
Reply to: Message 124 by PaulK
06-14-2011 1:09 PM


Re: Drifting into drift.
No. In natural selection the pressures are on the current population therefore k not k - 1 (they obviously have an effect on subsequent population via iteration).

I already stated that I had had to rethink some aspects of my position on drift, and that rethinking was what I intended to convey.


This message is a reply to:
 Message 124 by PaulK, posted 06-14-2011 1:09 PM PaulK has replied

Replies to this message:
 Message 126 by PaulK, posted 06-21-2011 3:24 PM Peter has replied

  
Peter
Member (Idle past 747 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 127 of 138 (621005)
06-22-2011 11:10 AM
Reply to: Message 126 by PaulK
06-21-2011 3:24 PM


Re: Drifting into drift.
No k is the current generation, the gene distribution of which is a function of past changes and current changes due to survivability.

This message is a reply to:
 Message 126 by PaulK, posted 06-21-2011 3:24 PM PaulK has replied

Replies to this message:
 Message 128 by PaulK, posted 06-22-2011 12:41 PM Peter has replied

  
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