Natural selection guarantees preservation

[SirKenin]

You say, lucaspa, that "Natural Selection is the process whereby the best design in a population is selected and then preserved for further design modification"

We know by definition that the best design is the design that assures the survival of the species. According to your posts, we must include the entire paragraph from Origin of a Species. According to Darwin:

If, during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organization, and I think this cannot be disputed; if there be, owing to the high geometric powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each beings welfare, in the same way as so many variations have occured useful to man. But if variations useful to any organic being do occur, assuredly individuals thus characterized will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will will tend to produce offspring similarly characterized. This principle of preservation, I have called, for the sake of brevity, Natural Selection."

So, we can't take part of it, and not others. We have to play on the same fair ground you use to argue against the Bible (And perhaps the same confounded logic that would make someone think you'd have to put Blue Whales on the Ark ) There MUST be a struggle for life for Natural Selection to work. I find this paragraph a little bit of a mouthful, so let's break it down into points

1) There MUST be variations in the parts of an organism.
2) There MUST be a struggle for life.
3) There MUST be variations in an organism that are advantageous to it.

This is a principle of preservation. Or, as defined in Darwin's Origin of a Species... "ILLUSTRATIONS OF THE ACTION OF NATURAL SELECTION, OR THE SURVIVAL OF THE FITTEST"

So... The first question I have is this. How is the best design preserved?

 

[Arikay]

One thing to point out, Lucaspa is a christian, so I doubt he argues against the bible, but against other peoples interpretations of it.

Its amazing how strong those blue whales are, to be able to survive that global flood and all.

I believe the "best design" is preserved by the organism having offspring and propogating its genetics.

 

[Late_Cretaceous]

If the basic logic of evolutionary theory was fundamentally flawed to such a degree that somebody could pick it apart while eating a bowl of cornflakes - then why does the theory of evolution persist? Evolutionary theory is the foundation of modern biology. It's concept is central to studies in ecology, environmental sciences, genetics, medicine, etc etc. Wouldn't these scientists have noticed something peculiar if it was such a terrible idea.

 

[Arikay]

Not if there was a giant conspiracy.

 

[Nathan Poe]

Not if there was a giant conspiracy.

Agent Arikay, you've revealed too much. The Conspiracy commands me to kill you now.

*BANG*

 

[David Gould]

Not if there was a giant conspiracy.

Shaddup .... your letting everyone know about us.

 

[SirKenin]

If the basic logic of evolutionary theory was fundamentally flawed to such a degree that somebody could pick it apart while eating a bowl of cornflakes - then why does the theory of evolution persist? Evolutionary theory is the foundation of modern biology. It's concept is central to studies in ecology, environmental sciences, genetics, medicine, etc etc. Wouldn't these scientists have noticed something peculiar if it was such a terrible idea.

Don't suppose I could talk you into answering the question?

 

[David Gould]

Don't suppose I could talk you into answering the question?

1) There MUST be variations in the parts of an organism.
2) There MUST be a struggle for life.
3) There MUST be variations in an organism that are advantageous to it.

You have left out one important factor - heritable charachteristics.

If we have two animals of one species, there will be slight variations between them. If any of these variations confer an advantage that contributes in any way to breeding success - for example, it enables one more offspring to be reared or one more offspring to survive - then the animal with that good variation will have more offspring than the animal without it.

As will the next generation. And the next. And the next. And so forth.
(assuming no environmental changes that remove the advantages that that variation grants).

This is how good variations tend to be preserved while negative ones tend to not be preserved.

 

[SirKenin]

I appreciate what you are saying, David, but how do you feel that I left that fact out?

Peace.

 

[David Gould]

I appreciate what you are saying, David, but how do you feel that I left that fact out?

Peace.

It is not in the list you gave, that's all.

 

[SirKenin]

It is not in the list you gave, that's all.

Hmm. I thought point 1 and 3 illustrated that, backed up by the quote from Origin of A Species at the beginning of this thread.

 

[OneLargeToe]

So... The first question I have is this. How is the best design preserved?

Applying some common sense to this question, I would imagine the best "designs" are preserved because the organism had offspring thus passing on it's genes. If the offspring contain the same successful traits, then they will do the same as their parents, so on and so forth.

 

[David Gould]

Hmm. I thought point 1 and 3 illustrated that, backed up by the quote from Origin of A Species at the beginning of this thread.

Neither point 1 or point 3 (as far as I can tell) mention heritability.

Anyway, assuming I missed it in your post, heritability plus the other parts answers your question about what preserves the good variations.

 

[Jet Black]

Not if there was a giant conspiracy.

I got my application papers through for the Great Scientific Conspiriacy Club this morning.

 

[lucaspa]

We know by definition that the best design is the design that assures the survival of the species. According to your posts, we must include the entire paragraph from Origin of a Species. According to Darwin:

No, that's not the best design by definition. And we are talking about survival of the INDIVIDUAL, not the species. Actually, not even "survival" always, but doing better in the metaphorical struggle for scarce resources.

The best variation can be determined by means independent of looking at the survival of an individual. And the design can be reverse-engineered to see what it does.

So, we can't take part of it, and not others. We have to play on the same fair ground you use to argue against the Bible

WHOA!! Where did this "argue against the Bible" come from? Where are we doing that?

I find this paragraph a little bit of a mouthful, so let's break it down into points

1) There MUST be variations in the parts of an organism.
2) There MUST be a struggle for life.
3) There MUST be variations in an organism that are advantageous to it.

Let's phrase that correctly.
1. There ARE variations in the parts of an organism.
2. THere IS a struggle for existence.
3. Since an organism varies in all its parts, some variations MUST be advantageous to the individual. There's no way that ALL of them can be detrimental.
4. Characteristics are inheritable.

So ... since all those apply, THEN the characteristics that are advantageous will allow the individual lucky enough to have them to do better in the struggle for existence, and those characteristics will be passed down (preserved) by inheritance.

A simple deductive argument. If the premises are true, then the conclusion inevitably follows.

How is the best design preserved?

The individual with that design is going to do better in the struggle for existence and leave more offspring. This has been documented by population genetics studies.

Straight Mendelian genetics yields the Hardy-Weinberg Law. This states that the frequency of an allele in a population remains constant. That is, if 1/10 the individuals in a population have A and 9/10 have B, then in the next generation, 1/10 will have A and 9/10 will have B.

However, if selection is at work, the frequency of the allele will change.
Therefore, the fitness of a new mutation is defined as the ratio of the actual frequency divided by the frequency expected by Mendelian genetics.

This is going to be greater than one in the case of favorable mutations. From that we get a selection coefficient such that fitness = 1 - s.

Now, doing the math we find that the advantageous allele A increases in frequency, per generation, by the amount delta p = (1/2)spq/(1-q).

If s = 0 or if s is less than 1 (deleterious), then delta p will be 0 or a negative number.

Remember, each variation is a design.

 

[lucaspa]

Hmm. I thought point 1 and 3 illustrated that, backed up by the quote from Origin of A Species at the beginning of this thread.

Then I am puzzled as to why you wondered how the design is preserved? It's obvious from Darwin's description of natural selection:

"assuredly individuals thus characterized will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will will tend to produce offspring similarly characterized. "

In an elimination tournament, don't the players with the best ability have the best chance of being preserved in the tournament (struggle for life)? Now, if they were allowed to reproduce and the others weren't, wouldn't their children tend to inherit their athletic ability? And also do well in that sport?

 

[SquareC]

In an elimination tournament, don't the players with the best ability have the best chance of being preserved in the tournament (struggle for life)? Now, if they were allowed to reproduce and the others weren't, wouldn't their children tend to inherit their athletic ability? And also do well in that sport?

Their children, barring damaging mutations and/or throwbacks to previous generations, will inherit their athletic ability, that is the abilities which make them successful in that sport. However, this does not guarantee that they will do well in that sport, because of such factors as their environmental exposures! As an example, the child of two champion figure skaters has the athletic abilities inherent in his genes to become a world class figure skater, but he is raised in Canada and many in his peer group are hockey fans. He is just as likely to become a hockey player and a most successful one, because of the exact same athletic abilities he inherited from his parents (i.g. balance, grace, strength, endurance....) but influenced by his environment, would not wish to be a figure skater. This child may take the opinion which many of his peers hold that this would make him appear "gay." (No insult is intended towards figure skaters here!) He'd be a great hockey player because of his inherited characteristics, wouldn't he? There we go on another tangent of the "nature vs. nurture" argument......I personally feel there are aspects of both at work in all.

 

[SirKenin]

I do want to get back to this, but I'm in over my head in paper work at the moment, and I can't devote any attention to this.. I will come back ASAP... I think lucaspa has a fantastic reply, worthy of attention.

 

[lucaspa]

Their children, barring damaging mutations and/or throwbacks to previous generations, will inherit their athletic ability, that is the abilities which make them successful in that sport. However, this does not guarantee that they will do well in that sport, because of such factors as their environmental exposures!

Let's not extend this analogy beyond what it is meant for. What you are talking about is culture, which is not present in most species. That is, an antelope doesn't have the opportunity of choosing a job that doesn't require it to run from a lion.

Also, if we extended the analogy, the children would also be put through an elimination tournament and thus wouldn't have the opportunity to avoid it like you said.

 

[Nathan David]

Don't suppose I could talk you into answering the question?

Arikay already answered it in the first reply to the OP:

I believe the "best design" is preserved by the organism having offspring and propogating its genetics.