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Author Topic:   Doesn't Natural Selection lead to Specified Complexity?
Dr Adequate
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Posts: 16112
Joined: 07-20-2006


Message 58 of 138 (616536)
05-23-2011 5:46 AM
Reply to: Message 57 by Peter
05-23-2011 5:21 AM


Drift
A mutation can become prevalent in a population for one of two reasons:

1) the mutation itself is in some-way preferred (maybe there is a predisposition towards a certain type of 'error' in some genes). Not saying there is, just saying that's a possible cause.

2) the mutation occurs in indivdiuals who also have a beneficial mutation.

3) Genetic drift.

In many ways I don't see what you want me to change in my thinking. All I have said is that the gene distribution in a population is an accumulation of genetic changes dominated by natural selection .

Quantitatively, this isn't the case. not only is most genetic variation due to drift, but also in most cases drift will beat selection. A new mutation which confers an n% advantage has (for small n) a 2√ón% chance of going on to be fixed by selection*; in the other cases it will be eliminated by genetic drift despite its advantages.

* Neglecting the cases in which selection wouldn't lead to fixation anyway, but to a stable equilibrium, as in the case of the sickle-cell allele.

It is true that selection acting on beneficial mutations is responsible for pretty much everything of interest; in particular, for the adaptation of organisms to their environment which deceives creationists into inferring design.

Ignore drift ... since it is not a filter and therefore not relevant to my OP.

It isn't, but that's no reason to speak as though it doesn't exist or as though it isn't what it in fact is.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 57 by Peter, posted 05-23-2011 5:21 AM Peter has responded

Replies to this message:
 Message 61 by Peter, posted 05-25-2011 5:55 AM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16112
Joined: 07-20-2006


Message 62 of 138 (616941)
05-25-2011 7:23 AM
Reply to: Message 61 by Peter
05-25-2011 5:55 AM


Re: Drift
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.

That depends what you mean by trend.

Consider the simplest case where you have two alleles a1 and a2 of some gene, both equally fit, with respective frequencies f1 and f2 in the population, such that f1 + f2 = 1.

Will these frequencies stay the same over time? They will not. Instead they will undergo what mathematicians call a "random walk", so that the graph of f1 against time will fluctuate up and down randomly.

Or rather, it will do so until either f1 = 0 or f1 = 1, when it will stick in that position, the allele a1 having been either eliminated from or fixed in the population. And it is certain (i.e. having probability 1) that it will end up doing one or the other. The only question is which. In fact it is the case that at any given time in the process the probability that a1 will go on to achieve fixation is just equal to the value of f1 at that time.

So there is no underlying trend for the frequency to drift one way rather than the other, but because it is subject to random fluctuation it will drift one way or the other, and end up at one of the two extremes.


This message is a reply to:
 Message 61 by Peter, posted 05-25-2011 5:55 AM Peter has responded

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Dr Adequate
Member
Posts: 16112
Joined: 07-20-2006


Message 89 of 138 (619736)
06-11-2011 9:10 PM
Reply to: Message 88 by SavageD
06-11-2011 7:28 PM


Re: Doesn't Natural Selection lead to Specified Complexity?
True, but, it is because these mechanism are specific that it points to an intelligent agent. Systems created by an intelligent agent tend to be very specific.

But so do systems created by various other means. An antibody against measles, for example, seems as specific to that virus as is a key to its lock, yet there is no intelligent agent.

Fair enough, though, I'll like to point out that your contradicting the first point you made here: "the exact adaptations that confer fitness in a given context can be quite specific." by saying:

"The vast majority of evidence shows that the mechanisms creating genetic variation, basically the various different forms of mutation, are not very specific at all."

No, you're confusing two different issues; the specificity of the thing produced and the mechanisms that produce it.

Take antibodies as an analogy again. The exact antibodies conferring immunity to a given disease are very specific. The mechanisms which create them are not very specific at all; there is not one special mechanism for producing antibodies against measles and another one for mumps.

As to why the underlying processes & mechanisms inside the organism are very "specific":

(1) The same mechanisms can found in many other organisms (namely ones of the same taxonomic group).

Your point here is obscure.

(2) Altering one of more of these mechanisms (DNA for example) can lead to the organisms death or can leave them at a major disadvantage to the environment (a deformed leg for example).

(3) These mechanisms are connected to other intricate components, these components must also be connected in a certain sequence. Without this sequence of interconnected parts the organism may die or it may not function properly.

So the variation in these mechanisms is subject to natural selection ...


This message is a reply to:
 Message 88 by SavageD, posted 06-11-2011 7:28 PM SavageD has responded

Replies to this message:
 Message 90 by SavageD, posted 06-12-2011 12:16 AM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16112
Joined: 07-20-2006


Message 91 of 138 (619746)
06-12-2011 1:23 AM
Reply to: Message 90 by SavageD
06-12-2011 12:16 AM


Re: Doesn't Natural Selection lead to Specified Complexity?
Your trying to obscure "specified complexity".

No I am not: this is why I did not mention "specified complexity" in any way.

This thread is about natural selection possibly leading to specified complexity, saying that something is simply "specific" won't suffice ...

It's what you said in the post I was replying to. I quote:

True, but, it is because these mechanism are specific that it points to an intelligent agent. Systems created by an intelligent agent tend to be very specific.

If you wish to deny that the specificity (and, indeed, complexity) of a measles antibody is an example of whatever you guys mean by "specified complexity", fine. But I was answering what you posted.

your argument is a straw man. ie an antibody protects against a specific virus (measles), therefore specified complexity can be produced without an intelligent agent.....

Perhaps you should find out what "straw man" means, especially as you managed to produce one in the very same paragraph in which you used the phrase.

A straw man is a misrepresentation of your opponents argument; as, for example, when you pretend that I said anything about specified complexity.

Another straw man. ie A specific antibody confers immunity against specific viruses. The specific mechanisms that create these antibodies are not specific at all because they can produce antibodies for other specific viruses as well. Therefore specified complexity is disproven

That is indeed "another straw man"; once more you have misrepresented my argument with a dishonesty that will prove to be as ineffective as it is shameless.

The underlying principle is that antibodies are used to counter act viruses and other foreign bodies, the mechanisms used to produce these antibodies could also be found within other organisms of the same specie. Many interconnected parts are used to create the immune system which leads to the production of different antibodies.

For these reasons we have "specified complexity," not simply because antibodies are created, but because an immense system of interconnected parts are needed to create these antibodies & these systems are not found in simply one organism, but many, because the mechanistic processes are carried on to new off spring.

And the antibodies are not produced by an intelligent agent, are they?

Not surprising as you have cloudy judgment.

Because I am not you, it is not my judgment, cloudy or otherwise, that makes your points obscure.

By a coincidence, the fact that I am not you is also the reason why the arguments that you have made up in your head and attributed to me are not mine.

The problem with ID supporters isn't natural selection, but the way by which it is used by evolutionists.

e.g (1) a group of reptiles ran up ramps flapping their arms while running from predators, those that were able to sprout wings over millions of years were naturally selected, they became birds.

e.g (2) a mammal decided to catch fish in the ocean because there was no food on land. Over millions of years it was able to grow flippers, develop sonar capabilities & grow a blow hole to the top of it's head, these features were all naturally selected for.

Note that these are not actual quotations from evolutionists, but stuff that you've made up in your head.

And then you have the cheek to use the phrase "straw man"; a piece of impudence which is hardly mitigated by the fact that apparently you don't know the meaning of the phrase.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
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Dr Adequate
Member
Posts: 16112
Joined: 07-20-2006


Message 96 of 138 (619785)
06-12-2011 11:02 AM
Reply to: Message 95 by SavageD
06-12-2011 10:20 AM


Re: A call for clarity
Basically I define an object of design as:

Any object which entails an intricate and ordered system of functionality(ies), consists of many different and inter-connected parts & contains structural integrity both on it's physically observable level(s) & sub-system level(s) (if any). These objects may also contain components unique to the natural environment (eg metal).

So by this definition an object of design is not necessarily an object which has been designed by anyone.

In which case the name is somewhat misleading.

As for specified complexity I would say that it is:

Any object which exhibits an intricate and ordered system of functionality(ies) (or sequential functionality), consisting of many different and inter-connected parts, which may also be comprised of materials unique to the natural environment (eg metal). This specified complexity must also be shown to exist in many other objects of the same type/kind.

So by this definition an object can possess specified complexity without its complexity having been specified by anyone.

In which case the name is somewhat misleading.

comprised of materials unique to the natural environment

What does this mean? Can you clarify? What would be an example of a material which is not "unique to the natural environment"?

This specified complexity must also be shown to exist in many other objects of the same type/kind.

How many? For example, it seems that when the first pendulum clock was made, it did not possess specified complexity, since it was the only one of its kind. When the second was made, there still weren't many of them. But after a certain point, after a certain number of them had been manufactured, suddenly they all acquired this property, including the first one if it was still extant.

Similarly it would seem that the aardvarks on Noah's Ark would have lacked specified complexity, being the only two of their kind; but their descendants would have acquired it after the aardvark kind had bred sufficiently; which would be a clear instance of specified complexity being produced by an unintelligent process.


This message is a reply to:
 Message 95 by SavageD, posted 06-12-2011 10:20 AM SavageD has responded

Replies to this message:
 Message 98 by SavageD, posted 06-12-2011 12:04 PM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16112
Joined: 07-20-2006


Message 116 of 138 (619865)
06-12-2011 8:14 PM
Reply to: Message 98 by SavageD
06-12-2011 12:04 PM


Re: A call for clarity
how so? please clarify

If an object fulfilled all your criteria, but was not designed, then by your definition we should still have to call it an "object of design", because your criteria for being an "object of design" do not include being designed.

Also, there are designed objects which do not fulfill your criteria --- a spoon, for example. Despite being an object that was designed, it does not qualify as an "object of design".

how so? please clarify

Well, again, because your definition of "specified complexity" does not include the proviso that the complexity should in fact have been specified. You mention things such as how many parts it has and what materials it's made of, but nothing whatsoever about someone drawing up a specification.

I'm referring to synthetic materials, materials that are not naturally found within a given environment, these materials are usually man made. Spiders create silk for example ...

Spider silk is not usually man-made.

Spiders create silk for example, it is unlikely that you would find silk randomly in our given environment, they require prior intelligence to be made (eg the spider)

The spider doesn't know how to make silk any more than I know how to grow hair out of the top of my head.

Finding the 'specified complexity' in 2 objects is good, finding it in 3 objects even better, finding it in 4 objects even better....

In what way? Either something possesses specified complexity or it doesn't. Does it somehow contain more specified complexity if there are lots of copies of it? Would I be more complex if I had a twin brother?

.....I do not believe in noahs ark, I'm agnostic....

Very well, consider the last dodo. Did it have a lower degree of "specified complexity" by virtue of being the last member of its species than dodos did when they were plentiful?


This message is a reply to:
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