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Author Topic:   Where do Creationists think the Theory of Evolution comes from?
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 33 of 109 (261978)
11-21-2005 1:06 PM
Reply to: Message 31 by Faith
11-21-2005 11:34 AM


and who CAN criticize it effectively?
Biologists, of course.
Evolutionists spend all their time fending off the criticisms of Creationists
Actually most evolutionists don't do much talking with creationists. Head up to your local university, walk into the biology department, and ask around about how many of the professors and grad students spend any significant time arguing with creationists.
I believe this is because it is all about the past and you cannot prove or disprove anything in the past, it is all speculation.
Does that really make any sense to you? That you can't come to confident conclusions about the past?
Did it occur to you that all observations are of things in the past? I mean, we don't observe the future, right? And the present doesn't last long enough - anything that happens in the present is in the past by the time we've registered it in our minds, so all observation occurs in the past.
If you don't believe that science can draw confident conclusions about the past, then there's nothing science can conclude at all. Yet, still, here you are, using a computer and benefiting from the application of science.

This message is a reply to:
 Message 31 by Faith, posted 11-21-2005 11:34 AM Faith has not replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 36 of 109 (261997)
11-21-2005 1:36 PM
Reply to: Message 35 by Faith
11-21-2005 1:34 PM


Yes, natural selection and artificial selection perform the same task of VARYING the types within a species.
That doesn't seem to be correct. Selection, of any type, contracts the variation of a species. It doesn't expand variation.
Mutation causes variation. Selection reduces variation.

This message is a reply to:
 Message 35 by Faith, posted 11-21-2005 1:34 PM Faith has replied

Replies to this message:
 Message 37 by Faith, posted 11-21-2005 3:10 PM crashfrog has replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 39 of 109 (262033)
11-21-2005 3:22 PM
Reply to: Message 37 by Faith
11-21-2005 3:10 PM


Yes, sorry, it's the mutation or genetic change that causes variation, but if selection of one kind or another (all the "evolutionary processes" select, not just Natural Selection) didn't happen it wouldn't come to be recognized AS a variation within the species.
Well, they're all recognized as variations within species. I'm sitting here in my wife's entomology lab, in front of six-foot stacks of Cornell drawers, and even though I could probably produce 200 specimens of one given species (say, southern corn rootworm) in about two minutes, every one of them would have individual characteristics; would represent an individual variant of that species.
Variation between individuals isn't something that only happens once in a while; it's the universal condition of living things.
And, what? "All evolutionary processes select?" Whatever gave you that idea? Mutation is not selective; it's random. Hence, "random mutation."
Every process that changes or "evolves" the creature reduces its genetic variability
No, because mutation is a source of increased genetic variability.
I mean, what's the deal here? You can't understand how you can have one process that expands variation, and another that contracts it? Is that it? You simply can't understand how both of those processess could work at the same time?

This message is a reply to:
 Message 37 by Faith, posted 11-21-2005 3:10 PM Faith has replied

Replies to this message:
 Message 41 by Faith, posted 11-21-2005 3:45 PM crashfrog has replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 42 of 109 (262038)
11-21-2005 3:46 PM
Reply to: Message 40 by Faith
11-21-2005 3:40 PM


Doesn't matter how many sources of variations you have, as long as the only way the change becomes established is through a method of selection that reduces genetic variability, and that is the case, evolution is impossible.
"Established"? Once it happens, it's established.
You don't have the first clue what's going on in a population's genetics, do you? No idea whatsoever, huh?

This message is a reply to:
 Message 40 by Faith, posted 11-21-2005 3:40 PM Faith has replied

Replies to this message:
 Message 43 by Faith, posted 11-21-2005 3:51 PM crashfrog has replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 45 of 109 (262047)
11-21-2005 3:55 PM
Reply to: Message 43 by Faith
11-21-2005 3:51 PM


What is erroneously termed "speciation" is in fact a condition of reduced genetic variability in comparison to the population it "evolved" from.
Which, firstly, isn't even true - in fact the reverse is often true, that a speciated subpopulation often has more genetic variability than its parent population, because density-dependant selection pressures are non-existent and thus aren't restricting variation.
Secondly, that doesn't explain why those subpopulations cease being able to breed with their parent population, but continue to be able to breed with each other.
Like I said, you don't have the first clue of what goes on in the genetics of a population, do you? You might as well just admit it; you've already made it obvious.

This message is a reply to:
 Message 43 by Faith, posted 11-21-2005 3:51 PM Faith has replied

Replies to this message:
 Message 49 by Faith, posted 11-22-2005 7:15 AM crashfrog has replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 47 of 109 (262051)
11-21-2005 4:01 PM
Reply to: Message 41 by Faith
11-21-2005 3:45 PM


Variability is the number of possible genetic expressions available -- numbers of genes, numbers of alleles, whatever.
And mutation results in new alleles. Thus, it's an expansion of the number of possible genetic expressions avaliable, and thus a source of variation. It's proven.
The reduction process cancels out any increase in variability conferred by the addition of a mutation.
Ah, but here's the thing. The reduction is not symmetrical. The variation expands in one direction, along one axis, but is contracted in another. Thus, the population evolves.
Consider a train running on 30 feet of track. One group of workers places 10 feet of rail at the front, and another group picks up 10 feet from the back. Now, you assert that the train goes nowhere because one group cancels out the other, but that's not what happens, because the deletion of track isn't symmetrical with the addition. The result you expect is that the train only travels 30 feet, but the result that actually happens is that the trains travels an arbitrary distance, 30 feet at a time.
Like I said, you don't understand what's going on. One process expands diversity, another contracts it; but they don't cancel out because they're assymetrical influences.

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 Message 41 by Faith, posted 11-21-2005 3:45 PM Faith has not replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 58 of 109 (262324)
11-22-2005 9:29 AM
Reply to: Message 49 by Faith
11-22-2005 7:15 AM


The cheetah continues to seem to me to be THE emblem of the direction of speciation, that is, in the direction as far from any evolutionary potential as you can get.
I don't see how the cheetah is emblematic of speciation. There's only one living species in its genus. If you want to talk about speciation, let's consider prolific speciators, like rats, bats, or antelope.
The more a particular type is selected by whatever means, whether naturally selected for its adaptable or survival-enhancing traits, or by the accidental conditions of population bottleneck, its ability to vary genetically is reduced.
You keep confusing actual variation with "potential" variation, and there's absolutely no reason to do so.
Consider the gene pool of a population of any organism you choose. The actual variability is the number of different alleles per gene in that population. That waxes and wanes over time; mutation adds new alleles, and selection changes their relative frequency in the population, sometimes eliminating alleles altogether. That's how actual variation works in a population.
Now, potential variability? The potential for new alleles is always there; the rate of mutation per billion base pairs - which is how mutation rates are measured - doesn't change depending on how many alleles are in the population, or how loarge the population is. The individuals in a population are all mutating at the same rate no matter the size or genetics of the population, so potential variability doesn't change.
The cheetah has no less potential variability now than it did before the bottleneck event, even though its actual genetic variability now is much reduced.
Following me, so far?
Does it occur "often" enough to be the mechanism of evolution, since the usual developments of "evolutionary processes" are in the direction of reduced variability.
I never said it was a mechanism, the mechanisms of evolution are still the same - random mutation, differential reproduction, heredity.
What I've described is a result. How often does it happen? I couldn't say. I don't think you can say either.

This message is a reply to:
 Message 49 by Faith, posted 11-22-2005 7:15 AM Faith has not replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 59 of 109 (262326)
11-22-2005 9:31 AM
Reply to: Message 56 by Faith
11-22-2005 9:01 AM


It remains true that genetic variability IS reduced by all the "mechanisms of evolution" such as natural selection, bottleneck and so on
Except for mutation. Mutation increases the number of variants in a population - it expands the variability of a population's gene pool.
And with somewhere between 5 and 500 new mutations per individual, depending on the species, that's a considerable influx of variation.
although I don't know enough about the genetics involved to argue it, somebody does and will eventually.
Nobody has. Does that maybe tell you something?

This message is a reply to:
 Message 56 by Faith, posted 11-22-2005 9:01 AM Faith has replied

Replies to this message:
 Message 61 by Faith, posted 11-22-2005 9:39 AM crashfrog has replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 60 of 109 (262329)
11-22-2005 9:34 AM
Reply to: Message 53 by iano
11-22-2005 8:32 AM


Here we have an idea in the very earliest embryonic stages and folk, rather than wonder (with genuine enquiring minds) if there is anything in it, attempt to rip it from the womb. Why is that?
Because they did wonder if there was anything in it, with a genuine open mind, took a look, and found that there wasn't anything there.
And, yet, people who openly assert their ulterior motive promulgate the idea as though its real science. That's why the reaction is so strong. If ID proponents would behave honestly, they wouldn't be so personally crucified for their erroneous conjecture.

This message is a reply to:
 Message 53 by iano, posted 11-22-2005 8:32 AM iano has not replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 63 of 109 (262338)
11-22-2005 9:47 AM
Reply to: Message 61 by Faith
11-22-2005 9:39 AM


All this emphasis on mutation seems like a brand new trick pulled out of a hat
Heh, no, trust me - mutation has been identified as a prominent mechanism of expanding variation for as long as we've understod genetics. There's nothing new about mutation.
It remains true that the processes that select any trait whatever lead to reduced genetic variability.
Sure. The selective processes of evolution reduce variation, to some degree. That they do not do so randomly is one of the driving forces of evolution.

This message is a reply to:
 Message 61 by Faith, posted 11-22-2005 9:39 AM Faith has replied

Replies to this message:
 Message 66 by Faith, posted 11-22-2005 11:34 AM crashfrog has replied

  
crashfrog
Member (Idle past 1496 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 67 of 109 (262397)
11-22-2005 11:55 AM
Reply to: Message 66 by Faith
11-22-2005 11:34 AM


I didn't say MUTATION was new, I said ALL THIS EMPHASIS on mutation is new.
It's not new. The emphasis on mutation as a source of genetic diversity is, again, as old as our understanding of genetic molecules. Watson and Crick, etc.
In fact, if anything, the current state of scientific thought is about decreasing the emphasis on purely random mutation as the main source of genetic diversity and phenotypic variation.
The emphasis is not new, and in fact, the trend is exactly the opposite of what you seem to think it is.
Most of it is not beneficial, much of it is destructive but who cares, the more the better.
Well, yeah. When you have a selective force, it doesn't matter how detrimental most of the phenotypic mutations are.

This message is a reply to:
 Message 66 by Faith, posted 11-22-2005 11:34 AM Faith has not replied

  
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